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Mehrabipour M, Nakhaei-Rad S, Dvorsky R, Lang A, Verhülsdonk P, Ahmadian MR, Piekorz RP. SIRT4 as a novel interactor and candidate suppressor of C-RAF kinase in MAPK signaling. Life Sci Alliance 2024; 7:e202302507. [PMID: 38499327 PMCID: PMC10948936 DOI: 10.26508/lsa.202302507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 03/06/2024] [Accepted: 03/07/2024] [Indexed: 03/20/2024] Open
Abstract
Cellular responses leading to development, proliferation, and differentiation depend on RAF/MEK/ERK signaling, which integrates and amplifies signals from various stimuli for downstream cellular responses. C-RAF activation has been reported in many types of tumor cell proliferation and developmental disorders, necessitating the discovery of potential C-RAF protein regulators. Here, we identify a novel and specific protein interaction between C-RAF among the RAF kinase paralogs, and SIRT4 among the mitochondrial sirtuin family members SIRT3, SIRT4, and SIRT5. Structurally, C-RAF binds to SIRT4 through the N-terminal cysteine-rich domain, whereas SIRT4 predominantly requires the C-terminus for full interaction with C-RAF. Interestingly, SIRT4 specifically interacts with C-RAF in a pre-signaling inactive (serine 259-phosphorylated) state. Consistent with this finding, the expression of SIRT4 in HEK293 cells results in an up-regulation of pS259-C-RAF levels and a concomitant reduction in MAPK signaling as evidenced by strongly decreased phospho-ERK signals. Thus, we propose an additional extra-mitochondrial function of SIRT4 as a cytosolic tumor suppressor of C-RAF-MAPK signaling, besides its metabolic tumor suppressor role of glutamate dehydrogenase and glutamate levels in mitochondria.
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Affiliation(s)
- Mehrnaz Mehrabipour
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University, Düsseldorf, Germany
| | - Saeideh Nakhaei-Rad
- Stem Cell Biology, and Regenerative Medicine Research Group, Institute of Biotechnology, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Radovan Dvorsky
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University, Düsseldorf, Germany
| | - Alexander Lang
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University, Düsseldorf, Germany
| | - Patrick Verhülsdonk
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University, Düsseldorf, Germany
| | - Mohammad R Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University, Düsseldorf, Germany
| | - Roland P Piekorz
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University, Düsseldorf, Germany
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Kazemein Jasemi NS, Mehrabipour M, Magdalena Estirado E, Brunsveld L, Dvorsky R, Ahmadian MR. Functional Classification and Interaction Selectivity Landscape of the Human SH3 Domain Superfamily. Cells 2024; 13:195. [PMID: 38275820 PMCID: PMC10814857 DOI: 10.3390/cells13020195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 01/09/2024] [Accepted: 01/17/2024] [Indexed: 01/27/2024] Open
Abstract
SRC homology 3 (SH3) domains are critical interaction modules that orchestrate the assembly of protein complexes involved in diverse biological processes. They facilitate transient protein-protein interactions by selectively interacting with proline-rich motifs (PRMs). A database search revealed 298 SH3 domains in 221 human proteins. Multiple sequence alignment of human SH3 domains is useful for phylogenetic analysis and determination of their selectivity towards PRM-containing peptides (PRPs). However, a more precise functional classification of SH3 domains is achieved by constructing a phylogenetic tree only from PRM-binding residues and using existing SH3 domain-PRP structures and biochemical data to determine the specificity within each of the 10 families for particular PRPs. In addition, the C-terminal proline-rich domain of the RAS activator SOS1 covers 13 of the 14 recognized proline-rich consensus sequence motifs, encompassing differential PRP pattern selectivity among all SH3 families. To evaluate the binding capabilities and affinities, we conducted fluorescence dot blot and polarization experiments using 25 representative SH3 domains and various PRPs derived from SOS1. Our analysis has identified 45 interacting pairs, with binding affinities ranging from 0.2 to 125 micromolar, out of 300 tested and potential new SH3 domain-SOS1 interactions. Furthermore, it establishes a framework to bridge the gap between SH3 and PRP interactions and provides predictive insights into the potential interactions of SH3 domains with PRMs based on sequence specifications. This novel framework has the potential to enhance the understanding of protein networks mediated by SH3 domain-PRM interactions and be utilized as a general approach for other domain-peptide interactions.
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Affiliation(s)
- Neda S. Kazemein Jasemi
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (N.S.K.J.); (M.M.); (R.D.)
| | - Mehrnaz Mehrabipour
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (N.S.K.J.); (M.M.); (R.D.)
| | - Eva Magdalena Estirado
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, P.O. Box 513, 5600MB Eindhoven, The Netherlands; (E.M.E.); (L.B.)
| | - Luc Brunsveld
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, P.O. Box 513, 5600MB Eindhoven, The Netherlands; (E.M.E.); (L.B.)
| | - Radovan Dvorsky
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (N.S.K.J.); (M.M.); (R.D.)
| | - Mohammad R. Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (N.S.K.J.); (M.M.); (R.D.)
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Hampel N, Georgy J, Mehrabipour M, Lang A, Lehmkuhl I, Scheller J, Ahmadian MR, Floss DM, Piekorz RP. CoCl 2 -triggered pseudohypoxic stress induces proteasomal degradation of SIRT4 via polyubiquitination of lysines K78 and K299. FEBS Open Bio 2023; 13:2187-2199. [PMID: 37803520 PMCID: PMC10699113 DOI: 10.1002/2211-5463.13715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 08/24/2023] [Accepted: 10/04/2023] [Indexed: 10/08/2023] Open
Abstract
SIRT4, together with SIRT3 and SIRT5, comprises the mitochondrially localized subgroup of sirtuins. SIRT4 regulates mitochondrial bioenergetics, dynamics (mitochondrial fusion), and quality control (mitophagy) via its NAD+ -dependent enzymatic activities. Here, we address the regulation of SIRT4 itself by characterizing its protein stability and degradation upon CoCl2 -induced pseudohypoxic stress that typically triggers mitophagy. Interestingly, we observed that of the mitochondrial sirtuins, only the protein levels of SIRT4 or ectopically expressed SIRT4-eGFP decrease upon CoCl2 treatment of HEK293 cells. Co-treatment with BafA1, an inhibitor of autophagosome-lysosome fusion required for autophagy/mitophagy, or the use of the proteasome inhibitor MG132, prevented CoCl2 -induced SIRT4 downregulation. Consistent with the proteasomal degradation of SIRT4, the lysine mutants SIRT4(K78R) and SIRT4(K299R) showed significantly reduced polyubiquitination upon CoCl2 treatment and were more resistant to pseudohypoxia-induced degradation as compared to SIRT4. Moreover, SIRT4(K78R) and SIRT4(K299R) displayed increased basal protein stability as compared to wild-type SIRT4 when subjected to MG132 treatment or cycloheximide (CHX) chase assays. Thus, our data indicate that stress-induced protein degradation of SIRT4 occurs through two mechanisms: (a) via mitochondrial autophagy/mitophagy, and (b) as a separate process via proteasomal degradation within the cytoplasm.
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Affiliation(s)
- Nils Hampel
- Institute of Biochemistry and Molecular Biology II, Medical FacultyHeinrich Heine University DüsseldorfUniversitätsstrasse 1Düsseldorf40225Germany
| | - Jacqueline Georgy
- Institute of Biochemistry and Molecular Biology II, Medical FacultyHeinrich Heine University DüsseldorfUniversitätsstrasse 1Düsseldorf40225Germany
| | - Mehrnaz Mehrabipour
- Institute of Biochemistry and Molecular Biology II, Medical FacultyHeinrich Heine University DüsseldorfUniversitätsstrasse 1Düsseldorf40225Germany
| | - Alexander Lang
- Institute of Biochemistry and Molecular Biology II, Medical FacultyHeinrich Heine University DüsseldorfUniversitätsstrasse 1Düsseldorf40225Germany
- Present address:
Department of Cardiology, Pulmonology, and Vascular Medicine, Medical FacultyHeinrich Heine University DüsseldorfGermany
| | - Isabell Lehmkuhl
- Institute of Biochemistry and Molecular Biology II, Medical FacultyHeinrich Heine University DüsseldorfUniversitätsstrasse 1Düsseldorf40225Germany
| | - Jürgen Scheller
- Institute of Biochemistry and Molecular Biology II, Medical FacultyHeinrich Heine University DüsseldorfUniversitätsstrasse 1Düsseldorf40225Germany
| | - Mohammad R. Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical FacultyHeinrich Heine University DüsseldorfUniversitätsstrasse 1Düsseldorf40225Germany
| | - Doreen M. Floss
- Institute of Biochemistry and Molecular Biology II, Medical FacultyHeinrich Heine University DüsseldorfUniversitätsstrasse 1Düsseldorf40225Germany
| | - Roland P. Piekorz
- Institute of Biochemistry and Molecular Biology II, Medical FacultyHeinrich Heine University DüsseldorfUniversitätsstrasse 1Düsseldorf40225Germany
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Mehrabipour M, Jasemi NSK, Dvorsky R, Ahmadian MR. A Systematic Compilation of Human SH3 Domains: A Versatile Superfamily in Cellular Signaling. Cells 2023; 12:2054. [PMID: 37626864 PMCID: PMC10453029 DOI: 10.3390/cells12162054] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Revised: 08/02/2023] [Accepted: 08/02/2023] [Indexed: 08/27/2023] Open
Abstract
SRC homology 3 (SH3) domains are fundamental modules that enable the assembly of protein complexes through physical interactions with a pool of proline-rich/noncanonical motifs from partner proteins. They are widely studied modular building blocks across all five kingdoms of life and viruses, mediating various biological processes. The SH3 domains are also implicated in the development of human diseases, such as cancer, leukemia, osteoporosis, Alzheimer's disease, and various infections. A database search of the human proteome reveals the existence of 298 SH3 domains in 221 SH3 domain-containing proteins (SH3DCPs), ranging from 13 to 720 kilodaltons. A phylogenetic analysis of human SH3DCPs based on their multi-domain architecture seems to be the most practical way to classify them functionally, with regard to various physiological pathways. This review further summarizes the achievements made in the classification of SH3 domain functions, their binding specificity, and their significance for various diseases when exploiting SH3 protein modular interactions as drug targets.
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Affiliation(s)
- Mehrnaz Mehrabipour
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (M.M.); (N.S.K.J.)
| | - Neda S. Kazemein Jasemi
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (M.M.); (N.S.K.J.)
| | - Radovan Dvorsky
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (M.M.); (N.S.K.J.)
- Center for Interdisciplinary Biosciences, P. J. Šafárik University, 040 01 Košice, Slovakia
| | - Mohammad R. Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (M.M.); (N.S.K.J.)
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5
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Nakhaei-Rad S, Haghighi F, Bazgir F, Dahlmann J, Busley AV, Buchholzer M, Kleemann K, Schänzer A, Borchardt A, Hahn A, Kötter S, Schanze D, Anand R, Funk F, Kronenbitter AV, Scheller J, Piekorz RP, Reichert AS, Volleth M, Wolf MJ, Cirstea IC, Gelb BD, Tartaglia M, Schmitt JP, Krüger M, Kutschka I, Cyganek L, Zenker M, Kensah G, Ahmadian MR. Molecular and cellular evidence for the impact of a hypertrophic cardiomyopathy-associated RAF1 variant on the structure and function of contractile machinery in bioartificial cardiac tissues. Commun Biol 2023; 6:657. [PMID: 37344639 DOI: 10.1038/s42003-023-05013-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 06/02/2023] [Indexed: 06/23/2023] Open
Abstract
Noonan syndrome (NS), the most common among RASopathies, is caused by germline variants in genes encoding components of the RAS-MAPK pathway. Distinct variants, including the recurrent Ser257Leu substitution in RAF1, are associated with severe hypertrophic cardiomyopathy (HCM). Here, we investigated the elusive mechanistic link between NS-associated RAF1S257L and HCM using three-dimensional cardiac bodies and bioartificial cardiac tissues generated from patient-derived induced pluripotent stem cells (iPSCs) harboring the pathogenic RAF1 c.770 C > T missense change. We characterize the molecular, structural, and functional consequences of aberrant RAF1-associated signaling on the cardiac models. Ultrastructural assessment of the sarcomere revealed a shortening of the I-bands along the Z disc area in both iPSC-derived RAF1S257L cardiomyocytes and myocardial tissue biopsies. The aforementioned changes correlated with the isoform shift of titin from a longer (N2BA) to a shorter isoform (N2B) that also affected the active force generation and contractile tensions. The genotype-phenotype correlation was confirmed using cardiomyocyte progeny of an isogenic gene-corrected RAF1S257L-iPSC line and was mainly reversed by MEK inhibition. Collectively, our findings uncovered a direct link between a RASopathy gene variant and the abnormal sarcomere structure resulting in a cardiac dysfunction that remarkably recapitulates the human disease.
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Affiliation(s)
- Saeideh Nakhaei-Rad
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Stem Cell Biology and Regenerative Medicine Research Group, Institute of Biotechnology, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Fereshteh Haghighi
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Clinic for Cardiothoracic and Vascular Surgery, University Medical Center Göttingen, Göttingen, Germany
- German Center for Cardiovascular Research (DZHK), partner site Göttingen, Göttingen, Germany
| | - Farhad Bazgir
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Julia Dahlmann
- German Center for Cardiovascular Research (DZHK), partner site Göttingen, Göttingen, Germany
- Institute of Human Genetics, University Hospital, Otto von Guericke-University, Magdeburg, Germany
| | - Alexandra Viktoria Busley
- German Center for Cardiovascular Research (DZHK), partner site Göttingen, Göttingen, Germany
- Stem Cell Unit, Clinic for Cardiology and Pneumology, University Medical Center Göttingen, Göttingen, Germany
- Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells", University of Göttingen, Göttingen, Germany
| | - Marcel Buchholzer
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Karolin Kleemann
- Clinic for Cardiothoracic and Vascular Surgery, University Medical Center Göttingen, Göttingen, Germany
- German Center for Cardiovascular Research (DZHK), partner site Göttingen, Göttingen, Germany
| | - Anne Schänzer
- Institute of Neuropathology, Justus Liebig University Giessen, Giessen, Germany
| | - Andrea Borchardt
- Institute of Biochemistry and Molecular Biology I, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Andreas Hahn
- Department of Child Neurology, Justus Liebig University Giessen, 35392, Giessen, Germany
| | - Sebastian Kötter
- Institute of Cardiovascular Physiology, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Denny Schanze
- Institute of Human Genetics, University Hospital, Otto von Guericke-University, Magdeburg, Germany
| | - Ruchika Anand
- Institute of Biochemistry and Molecular Biology I, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Florian Funk
- Institute of Pharmacology, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Annette Vera Kronenbitter
- Institute of Pharmacology, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Jürgen Scheller
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Roland P Piekorz
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Andreas S Reichert
- Institute of Biochemistry and Molecular Biology I, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Marianne Volleth
- Institute of Human Genetics, University Hospital, Otto von Guericke-University, Magdeburg, Germany
| | - Matthew J Wolf
- Department of Medicine and Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville, VA, 22908, USA
| | - Ion Cristian Cirstea
- Institute of Comparative Molecular Endocrinology, University of Ulm, Helmholtzstrasse 8/1, 89081, Ulm, Germany
| | - Bruce D Gelb
- Mindich Child Health and Development Institute and Departments of Pediatrics and Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Marco Tartaglia
- Molecular Genetics and Functional Genomics, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146, Rome, Italy
| | - Joachim P Schmitt
- Institute of Pharmacology, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Martina Krüger
- Institute of Cardiovascular Physiology, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Ingo Kutschka
- Clinic for Cardiothoracic and Vascular Surgery, University Medical Center Göttingen, Göttingen, Germany
- German Center for Cardiovascular Research (DZHK), partner site Göttingen, Göttingen, Germany
| | - Lukas Cyganek
- German Center for Cardiovascular Research (DZHK), partner site Göttingen, Göttingen, Germany
- Stem Cell Unit, Clinic for Cardiology and Pneumology, University Medical Center Göttingen, Göttingen, Germany
- Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells", University of Göttingen, Göttingen, Germany
| | - Martin Zenker
- Institute of Human Genetics, University Hospital, Otto von Guericke-University, Magdeburg, Germany.
| | - George Kensah
- Clinic for Cardiothoracic and Vascular Surgery, University Medical Center Göttingen, Göttingen, Germany.
- German Center for Cardiovascular Research (DZHK), partner site Göttingen, Göttingen, Germany.
| | - Mohammad R Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
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Mohr I, Mirzaiebadizi A, Sanyal SK, Chuenban P, Ahmadian MR, Ivanov R, Bauer P. Characterization of the small Arabidopsis thaliana GTPase and ADP-ribosylation factor-like 2 protein TITAN5. bioRxiv 2023:2023.04.27.538563. [PMID: 37162876 PMCID: PMC10168340 DOI: 10.1101/2023.04.27.538563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Small GTPases comprise key proteins in signal transduction that function by conformational switching ability between GDP- and GTP-bound states. The ADP-ribosylation factor (ARF) family is involved in vesicle trafficking and cellular functions. Though evolutionarily well conserved, little is known about ARF and ARF-like GTPases in plants. Here, we characterized functional properties and cellular localization of the essential small ARF-like GTPase TITAN5/HALLIMASCH/ARL2/ARLC1 (hereafter termed TTN5) from Arabidopsis thaliana. TTN5 showed rapid guanine nucleotide exchange capacity comparable to that of human counterparts, but a remarkably low GTP hydrolysis reaction. A TTN5Q70L mutant had enhanced nucleotide exchange activity, indicative of intracellular activation, while TTN5T30N with fast nucleotide dissociation can be considered a dominant-negative form. This suggests that TTN5 is present in GTP-loaded active form in the cells. YFP-tagged TTN5 and the two derived mutant variants were located at multiple sites of the endomembrane system in the epidermis of Arabidopsis seedlings and Nicotiana benthamiana leaves. While YFP-TTN5 and YFP-TTN5Q70L were highly mobile in the cells, mobility was reduced for TTN5T30N. Colocalization with endomembrane markers in combination with pharmacological treatments resolved localization at membrane sites and showed that YFP-TTN5 and YFP-TTN5Q70L were located in Golgi stacks, multivesicular bodies, while this was less the case for YFP-TTN5T30N. On the other hand, all three TTN5 forms were located at the plasma membrane. Hence, the unusual capacity of rapid nucleotide exchange activity of the small ARF-like GTPase TTN5 is linked with cell membrane dynamics, likely associated with vesicle transport pathways in the endomembrane system.
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Affiliation(s)
- Inga Mohr
- Institute of Botany, Heinrich Heine University, 40225 Düsseldorf, Germany
| | - Amin Mirzaiebadizi
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University, Düsseldorf, Germany
| | - Sibaji K Sanyal
- Institute of Botany, Heinrich Heine University, 40225 Düsseldorf, Germany
| | - Pichaporn Chuenban
- Institute of Botany, Heinrich Heine University, 40225 Düsseldorf, Germany
| | - Mohammad R Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University, Düsseldorf, Germany
| | - Rumen Ivanov
- Institute of Botany, Heinrich Heine University, 40225 Düsseldorf, Germany
| | - Petra Bauer
- Institute of Botany, Heinrich Heine University, 40225 Düsseldorf, Germany
- Cluster of Excellence on Plant Sciences, Heinrich Heine University, 40225 Düsseldorf, Germany
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7
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Nakhaei-Rad S, Janatifard F, Dvorsky R, Ahmadian MR, Housaindokht MR. Molecular analyses of the C-terminal CRAF variants associated with cardiomyopathy reveal their opposing impacts on the active conformation of the kinase domain. J Biomol Struct Dyn 2023; 41:15328-15338. [PMID: 36927384 DOI: 10.1080/07391102.2023.2187221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 02/28/2023] [Indexed: 03/18/2023]
Abstract
The germline mutations in the C-terminus of CRAF kinase, particularly L603, and S612T/L613V, are associated with congenital heart disorders, for example, dilated cardiomyopathy (DCM) and hypertrophic cardiomyopathy (HCM). The experimental data suggest that genetic alternation at position 603 impairs, while those at positions 612/613 enhance the CRAF kinase activity. However, the underlying mechanistic details by which these mutations increase or decrease kinase activity remain elusive. Therefore, we applied molecular dynamic simulation to investigate the impacts of these point mutations on the conformation of the CRAF kinase domain. The results revealed that the substitution of Leucine 603 for proline transits the kinase domain to a state that exhibits the molecular hallmarks of an inactive kinase, for example, a closed activation loop, 'αC-helix out' conformation and a distorted regulatory hydrophobic spine. However, two HCM-associated variants (S612T and L613V) show features of an active conformation, such as an open activation loop conformation, 'αC-helix in', the assembly of the hydrophobic spine, and more surface-exposed catalytic residues of phosphoryl transfer reaction. Overall, our study provides a mechanistic basis for the contradictory effects of the CRAF variants associated with HCM and DCM.
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Affiliation(s)
- Saeideh Nakhaei-Rad
- Stem Cell Biology, and Regenerative Medicine Research Group, Institute of Biotechnology, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Fatemeh Janatifard
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
| | | | - Mohammad R Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
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8
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Nauth T, Bazgir F, Voß H, Brandenstein LI, Mosaddeghzadeh N, Rickassel V, Deden S, Gorzelanny C, Schlüter H, Ahmadian MR, Rosenberger G. Cutaneous manifestations in Costello syndrome: HRAS p.Gly12Ser affects RIN1-mediated integrin trafficking in immortalized epidermal keratinocytes. Hum Mol Genet 2023; 32:304-318. [PMID: 35981076 DOI: 10.1093/hmg/ddac188] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 07/15/2022] [Accepted: 08/07/2022] [Indexed: 01/18/2023] Open
Abstract
Heterozygous germline missense variants in the HRAS gene underlie Costello syndrome (CS). The molecular basis for cutaneous manifestations in CS is largely unknown. We used an immortalized human cell line, HaCaT keratinocytes, stably expressing wild-type or CS-associated (p.Gly12Ser) HRAS and defined RIN1 as quantitatively most prominent, high-affinity effector of active HRAS in these cells. As an exchange factor for RAB5 GTPases, RIN1 is involved in endosomal sorting of cell-adhesion integrins. RIN1-dependent RAB5A activation was strongly increased by HRASGly12Ser, and HRAS-RIN1-ABL1/2 signaling was induced in HRASWT- and HRASGly12Ser-expressing cells. Along with that, HRASGly12Ser expression decreased total integrin levels and enriched β1 integrin in RAB5- and EEA1-positive early endosomes. The intracellular level of active β1 integrin was increased in HRASGly12Ser HaCaT keratinocytes due to impaired recycling, whereas RIN1 disruption raised β1 integrin cell surface distribution. HRASGly12Ser induced co-localization of β1 integrin with SNX17 and RAB7 in early/sorting and late endosomes, respectively. Thus, by retaining β1 integrin in intracellular endosomal compartments, HRAS-RIN1 signaling affects the subcellular availability of β1 integrin. This may interfere with integrin-dependent processes as we detected for HRASGly12Ser cells spreading on fibronectin. We conclude that dysregulation of receptor trafficking and integrin-dependent processes such as cell adhesion are relevant in the pathobiology of CS.
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Affiliation(s)
- Theresa Nauth
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Farhad Bazgir
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine University, 40225 Düsseldorf, Germany
| | - Hannah Voß
- Institute of Clinical Chemistry and Laboratory Medicine, Section Mass Spectrometry and Proteomics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Laura I Brandenstein
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Niloufar Mosaddeghzadeh
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine University, 40225 Düsseldorf, Germany
| | - Verena Rickassel
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Sophia Deden
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Christian Gorzelanny
- Department of Dermatology and Venereology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Hartmut Schlüter
- Institute of Clinical Chemistry and Laboratory Medicine, Section Mass Spectrometry and Proteomics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Mohammad R Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine University, 40225 Düsseldorf, Germany
| | - Georg Rosenberger
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
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9
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Pudewell S, Lissy J, Nakhaeizadeh H, Mosaddeghzadeh N, Nakhaei-Rad S, Dvorsky R, Ahmadian MR. New mechanistic insights into the RAS-SIN1 interaction at the membrane. Front Cell Dev Biol 2022; 10:987754. [PMID: 36274845 PMCID: PMC9583166 DOI: 10.3389/fcell.2022.987754] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
Stress-activated MAP kinase-interacting protein 1 (SIN1) is a central member of the mTORC2 complex that contains an N-terminal domain (NTD), a conserved region in the middle (CRIM), a RAS-binding domain (RBD), and a pleckstrin homology domain. Recent studies provided valuable structural and functional insights into the interactions of SIN1 and the RAS-binding domain of RAS proteins. However, the mechanism for a reciprocal interaction of the RBD-PH tandem with RAS proteins and the membrane as an upstream event to spatiotemporal mTORC2 regulation is not clear. The biochemical assays in this study led to the following results: 1) all classical RAS paralogs, including HRAS, KRAS4A, KRAS4B, and NRAS, can bind to SIN1-RBD in biophysical and SIN1 full length (FL) in cell biology experiments; 2) the SIN1-PH domain modulates interactions with various types of membrane phosphoinositides and constantly maintains a pool of SIN1 at the membrane; and 3) a KRAS4A-dependent decrease in membrane binding of the SIN1-RBD-PH tandem was observed, suggesting for the first time a mechanistic influence of KRAS4A on SIN1 membrane association. Our study strengthens the current mechanistic understanding of SIN1-RAS interaction and suggests membrane interaction as a key event in the control of mTORC2-dependent and mTORC2-independent SIN1 function.
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Affiliation(s)
- Silke Pudewell
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Jana Lissy
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Hossein Nakhaeizadeh
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Niloufar Mosaddeghzadeh
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Saeideh Nakhaei-Rad
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Stem Cell Biology and Regenerative Medicine Research Group, Institute of Biotechnology, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Radovan Dvorsky
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Center for Interdisciplinary Biosciences, P. J. Šafárik University, Košice, Slovakia
| | - Mohammad R. Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- *Correspondence: Mohammad R. Ahmadian,
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10
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Meng JH, Chen CX, Ahmadian MR, Zan H, Luo KJ, Jiang JX. Cross-Activation of Hemichannels/Gap Junctions and Immunoglobulin-Like Domains in Innate–Adaptive Immune Responses. Front Immunol 2022; 13:882706. [PMID: 35911693 PMCID: PMC9334851 DOI: 10.3389/fimmu.2022.882706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 06/23/2022] [Indexed: 11/13/2022] Open
Abstract
Hemichannels (HCs)/gap junctions (GJs) and immunoglobulin (Ig)-like domain-containing proteins (IGLDCPs) are involved in the innate–adaptive immune response independently. Despite of available evidence demonstrating the importance of HCs/GJs and IGLDCPs in initiating, implementing, and terminating the entire immune response, our understanding of their mutual interactions in immunological function remains rudimentary. IGLDCPs include immune checkpoint molecules of the immunoglobulin family expressed in T and B lymphocytes, most of which are cluster of differentiation (CD) antigens. They also constitute the principal components of the immunological synapse (IS), which is formed on the cell surface, including the phagocytic synapse, T cell synapse, B cell synapse, and astrocytes–neuronal synapse. During the three stages of the immune response, namely innate immunity, innate–adaptive immunity, and adaptive immunity, HCs/GJs and IGLDCPs are cross-activated during the entire process. The present review summarizes the current understanding of HC-released immune signaling factors that influence IGLDCPs in regulating innate–adaptive immunity. ATP-induced “eat me” signals released by HCs, as well as CD31, CD47, and CD46 “don’t eat me” signaling molecules, trigger initiation of innate immunity, which serves to regulate phagocytosis. Additionally, HC-mediated trogocytosis promotes antigen presentation and amplification. Importantly, HC-mediated CD4+ T lymphocyte activation is critical in the transition of the innate immune response to adaptive immunity. HCs also mediate non-specific transcytosis of antibodies produced by mature B lymphocytes, for instance, IgA transcytosis in ovarian cancer cells, which triggers innate immunity. Further understanding of the interplay between HCs/GJs and IGLDCPs would aid in identifying therapeutic targets that regulate the HC–Ig-like domain immune response, thereby providing a viable treatment strategy for immunological diseases. The present review delineates the clinical immunology-related applications of HC–Ig-like domain cross-activation, which would greatly benefit medical professionals and immunological researchers alike. HCs/GJs and IGLDCPs mediate phagocytosis via ATP; “eat me and don’t eat me” signals trigger innate immunity; HC-mediated trogocytosis promotes antigen presentation and amplification in innate–adaptive immunity; HCs also mediate non-specific transcytosis of antibodies produced by mature B lymphocytes in adaptive immunity.
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Affiliation(s)
- Jiang-Hui Meng
- School of Life Sciences, Yunnan University, Kunming, China
- Key Laboratory of the University in Yunnan Province for International Cooperation in Intercellular Communications and Regulations, Yunnan University, Kunming, China
| | - Chang-Xu Chen
- School of Life Sciences, Yunnan University, Kunming, China
- Key Laboratory of the University in Yunnan Province for International Cooperation in Intercellular Communications and Regulations, Yunnan University, Kunming, China
| | - Mohammad R. Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Hong Zan
- Department of Microbiology, Immunology and Molecular Genetics, University of Texas Health Science Center, San Antonio, TX, United States
| | - Kai-Jun Luo
- School of Life Sciences, Yunnan University, Kunming, China
- Key Laboratory of the University in Yunnan Province for International Cooperation in Intercellular Communications and Regulations, Yunnan University, Kunming, China
- *Correspondence: Kai-Jun Luo, ; Jean X. Jiang,
| | - Jean X. Jiang
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX, United States
- *Correspondence: Kai-Jun Luo, ; Jean X. Jiang,
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11
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Mosaddeghzadeh N, Nouri K, Krumbach OHF, Amin E, Dvorsky R, Ahmadian MR. Selectivity Determinants of RHO GTPase Binding to IQGAPs. Int J Mol Sci 2021; 22:12596. [PMID: 34830479 PMCID: PMC8625570 DOI: 10.3390/ijms222212596] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 11/16/2021] [Accepted: 11/19/2021] [Indexed: 12/13/2022] Open
Abstract
IQ motif-containing GTPase-activating proteins (IQGAPs) modulate a wide range of cellular processes by acting as scaffolds and driving protein components into distinct signaling networks. Their functional states have been proposed to be controlled by members of the RHO family of GTPases, among other regulators. In this study, we show that IQGAP1 and IQGAP2 can associate with CDC42 and RAC1-like proteins but not with RIF, RHOD, or RHO-like proteins, including RHOA. This seems to be based on the distribution of charged surface residues, which varies significantly among RHO GTPases despite their high sequence homology. Although effector proteins bind first to the highly flexible switch regions of RHO GTPases, additional contacts outside are required for effector activation. Sequence alignment and structural, mutational, and competitive biochemical analyses revealed that RHO GTPases possess paralog-specific residues outside the two highly conserved switch regions that essentially determine the selectivity of RHO GTPase binding to IQGAPs. Amino acid substitution of these specific residues in RHOA to the corresponding residues in RAC1 resulted in RHOA association with IQGAP1. Thus, electrostatics most likely plays a decisive role in these interactions.
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Affiliation(s)
- Niloufar Mosaddeghzadeh
- Medical Faculty, Institute of Biochemistry and Molecular Biology II, University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (N.M.); (K.N.); (O.H.F.K.); (E.A.); (R.D.)
| | - Kazem Nouri
- Medical Faculty, Institute of Biochemistry and Molecular Biology II, University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (N.M.); (K.N.); (O.H.F.K.); (E.A.); (R.D.)
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Oliver H. F. Krumbach
- Medical Faculty, Institute of Biochemistry and Molecular Biology II, University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (N.M.); (K.N.); (O.H.F.K.); (E.A.); (R.D.)
| | - Ehsan Amin
- Medical Faculty, Institute of Biochemistry and Molecular Biology II, University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (N.M.); (K.N.); (O.H.F.K.); (E.A.); (R.D.)
- Medical Faculty, Institute of Neural and Sensory Physiology, University Hospital Düsseldorf, Heinrich Heine University, 40225 Düsseldorf, Germany
| | - Radovan Dvorsky
- Medical Faculty, Institute of Biochemistry and Molecular Biology II, University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (N.M.); (K.N.); (O.H.F.K.); (E.A.); (R.D.)
| | - Mohammad R. Ahmadian
- Medical Faculty, Institute of Biochemistry and Molecular Biology II, University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (N.M.); (K.N.); (O.H.F.K.); (E.A.); (R.D.)
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12
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Heise D, Derrac Soria A, Hansen S, Dambietz C, Akbarzadeh M, Berg AF, Waetzig GH, Jones SA, Dvorsky R, Ahmadian MR, Scheller J, Moll JM. Selective inhibition of IL-6 trans-signaling by a miniaturized, optimized chimeric soluble gp130 inhibits T H17 cell expansion. Sci Signal 2021; 14:eabc3480. [PMID: 34404751 DOI: 10.1126/scisignal.abc3480] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The cytokine interleukin-6 (IL-6) signals through three mechanisms called classic signaling, trans-signaling, and trans-presentation. IL-6 trans-signaling is distinctly mediated through a soluble form of its transmembrane receptor IL-6R (sIL-6R) and the coreceptor gp130 and is implicated in multiple autoimmune diseases. Although a soluble form of gp130 (sgp130) inhibits only IL-6 trans-signaling, it also blocks an analogous trans-signaling mechanism of IL-11 and its soluble receptor sIL-11R. Here, we report miniaturized chimeric soluble gp130 variants that efficiently trap IL-6:sIL-6R but not IL-11:sIL-11R complexes. We designed a novel IL-6 trans-signaling trap by fusing a miniaturized sgp130 variant to an IL-6:sIL-6R complex-binding nanobody and the Fc portion of immunoglobulin G (IgG). This trap, called cs-130Fc, exhibited improved inhibition of as well as increased selectivity for IL-6 trans-signaling compared to the conventional fusion protein sgp130Fc. We introduced affinity-enhancing mutations in cs-130Fc and sgp130Fc that further improved selectivity toward IL-6 trans-signaling. Moreover, cs-130Fc efficiently inhibited the expansion of T helper 17 (TH17) cells in cultures of mouse CD4+ T cells treated with IL-6:sIL-6R. Thus, these variants may provide or lead to the development of more precisely targeted therapeutics for inflammatory disorders associated with IL-6 trans-signaling.
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Affiliation(s)
- Denise Heise
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, Düsseldorf 40225, Germany
| | - Alicia Derrac Soria
- Division of Infection and Immunity, School of Medicine, Systems Immunity University Research Institute, College of Biomedical and Life Sciences, Cardiff University, Cardiff CF14 4XN, UK
| | - Selina Hansen
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, Düsseldorf 40225, Germany
| | - Christine Dambietz
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, Düsseldorf 40225, Germany
| | - Mohammad Akbarzadeh
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, Düsseldorf 40225, Germany
| | - Anna F Berg
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, Düsseldorf 40225, Germany
| | - Georg H Waetzig
- Institute of Clinical Molecular Biology, Kiel University and University Medical Center Schleswig-Holstein, Kiel 24105, Germany
- CONARIS Research Institute AG, Kiel 24118, Germany
| | - Simon A Jones
- Division of Infection and Immunity, School of Medicine, Systems Immunity University Research Institute, College of Biomedical and Life Sciences, Cardiff University, Cardiff CF14 4XN, UK
| | - Radovan Dvorsky
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, Düsseldorf 40225, Germany
| | - Mohammad R Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, Düsseldorf 40225, Germany
| | - Jürgen Scheller
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, Düsseldorf 40225, Germany.
| | - Jens M Moll
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, Düsseldorf 40225, Germany.
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13
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Motta M, Sagi-Dain L, Krumbach OHF, Hahn A, Peleg A, German A, Lissewski C, Coppola S, Pantaleoni F, Kocherscheid L, Altmüller F, Schanze D, Logeswaran T, Chahrokh-Zadeh S, Munzig A, Nakhaei-Rad S, Cavé H, Ahmadian MR, Tartaglia M, Zenker M. Activating MRAS mutations cause Noonan syndrome associated with hypertrophic cardiomyopathy. Hum Mol Genet 2021; 29:1772-1783. [PMID: 31108500 DOI: 10.1093/hmg/ddz108] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 05/14/2019] [Accepted: 05/14/2019] [Indexed: 02/07/2023] Open
Abstract
The RASopathies are a group of genetic syndromes caused by upregulated RAS signaling. Noonan syndrome (NS), the most common entity among the RASopathies, is characterized mainly by short stature, cardiac anomalies and distinctive facial features. Mutations in multiple RAS-MAPK pathway-related genes have been associated with NS and related phenotypes. We describe two unrelated patients presenting with hypertrophic cardiomyopathy (HCM) and dysmorphic features suggestive of NS. One of them died in the neonatal period because of cardiac failure. Targeted sequencing revealed de novo MRAS variants, c.203C > T (p.Thr68Ile) and c.67G > C (p.Gly23Arg) as causative events. MRAS has only recently been related to NS based on the observation of two unrelated affected individuals with de novo variants involving the same codons here found mutated. Gly23 and Thr68 are highly conserved residues, and the corresponding codons are known hotspots for RASopathy-associated mutations in other RAS proteins. Functional analyses documented high level of activation of MRAS mutants due to impaired GTPase activity, which was associated with constitutive plasma membrane targeting, prolonged localization in non-raft microdomains, enhanced binding to PPP1CB and SHOC2 protein, and variably increased MAPK and PI3K-AKT activation. This report provides additional evidence that a narrow spectrum of activating mutations in MRAS represents another rare cause of NS, and that MRAS has to be counted among the RASopathy genes predisposing to HCM. Moreover, our findings further emphasize the relevance of the MRAS-SHOC2-PPP1CB axis in the control of MAPK signaling, and the contribution of both MAPK and PI3K-AKT pathways in MRAS functional upregulation.
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Affiliation(s)
- Marialetizia Motta
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, Rome, Italy
| | - Lena Sagi-Dain
- The Human Genetic institute, Carmel Medical Center, Ruth and Bruce Rappaport Faculty of Medicine, Israel Institute of Technology, Haifa, Israel
| | - Oliver H F Krumbach
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany
| | - Andreas Hahn
- Department of Child Neurology, University Hospital, Gießen, Germany
| | - Amir Peleg
- The Human Genetic institute, Carmel Medical Center, Ruth and Bruce Rappaport Faculty of Medicine, Israel Institute of Technology, Haifa, Israel
| | - Alina German
- Pediatric Department, Bnai-Zion Medical Center and Clalit Health Maintenance Organization, Haifa, Israel
| | | | - Simona Coppola
- National Centre for Rare Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Francesca Pantaleoni
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, Rome, Italy
| | | | | | - Denny Schanze
- Institute of Human Genetics, University Hospital, Magdeburg, Germany
| | | | | | - Anna Munzig
- Center of Human Genetics and Laboratory Diagnostics, Martinsried, Germany
| | - Saeideh Nakhaei-Rad
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany
| | - Hélène Cavé
- Assistance Publique des Hôpitaux de Paris (AP-HP), Hôpital Robert Debré, Département de Génétique, 75019 Paris, France.,INSERM UMR 1131, Institut de Recherche Saint-Louis, Université de Paris, 75010 Paris, France
| | - Mohammad R Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany
| | - Marco Tartaglia
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, Rome, Italy
| | - Martin Zenker
- Institute of Human Genetics, University Hospital, Magdeburg, Germany
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14
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Pudewell S, Wittich C, Kazemein Jasemi NS, Bazgir F, Ahmadian MR. Accessory proteins of the RAS-MAPK pathway: moving from the side line to the front line. Commun Biol 2021; 4:696. [PMID: 34103645 PMCID: PMC8187363 DOI: 10.1038/s42003-021-02149-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 04/23/2021] [Indexed: 02/07/2023] Open
Abstract
Health and disease are directly related to the RTK-RAS-MAPK signalling cascade. After more than three decades of intensive research, understanding its spatiotemporal features is afflicted with major conceptual shortcomings. Here we consider how the compilation of a vast array of accessory proteins may resolve some parts of the puzzles in this field, as they safeguard the strength, efficiency and specificity of signal transduction. Targeting such modulators, rather than the constituent components of the RTK-RAS-MAPK signalling cascade may attenuate rather than inhibit disease-relevant signalling pathways.
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Affiliation(s)
- Silke Pudewell
- grid.411327.20000 0001 2176 9917Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, Düsseldorf, Germany
| | - Christoph Wittich
- grid.411327.20000 0001 2176 9917Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, Düsseldorf, Germany
| | - Neda S. Kazemein Jasemi
- grid.411327.20000 0001 2176 9917Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, Düsseldorf, Germany
| | - Farhad Bazgir
- grid.411327.20000 0001 2176 9917Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, Düsseldorf, Germany
| | - Mohammad R. Ahmadian
- grid.411327.20000 0001 2176 9917Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, Düsseldorf, Germany
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15
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Rezaei Adariani S, Kazemein Jasemi NS, Bazgir F, Wittich C, Amin E, Seidel CAM, Dvorsky R, Ahmadian MR. A comprehensive analysis of RAS-effector interactions reveals interaction hotspots and new binding partners. J Biol Chem 2021; 296:100626. [PMID: 33930461 PMCID: PMC8163975 DOI: 10.1016/j.jbc.2021.100626] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/25/2021] [Accepted: 03/31/2021] [Indexed: 02/07/2023] Open
Abstract
RAS effectors specifically interact with GTP-bound RAS proteins to link extracellular signals to downstream signaling pathways. These interactions rely on two types of domains, called RAS-binding (RB) and RAS association (RA) domains, which share common structural characteristics. Although the molecular nature of RAS-effector interactions is well-studied for some proteins, most of the RA/RB-domain-containing proteins remain largely uncharacterized. Here, we searched through human proteome databases, extracting 41 RA domains in 39 proteins and 16 RB domains in 14 proteins, each of which can specifically select at least one of the 25 members in the RAS family. We next comprehensively investigated the sequence–structure–function relationship between different representatives of the RAS family, including HRAS, RRAS, RALA, RAP1B, RAP2A, RHEB1, and RIT1, with all members of RA domain family proteins (RASSFs) and the RB-domain-containing CRAF. The binding affinity for RAS-effector interactions, determined using fluorescence polarization, broadly ranged between high (0.3 μM) and very low (500 μM) affinities, raising interesting questions about the consequence of these variable binding affinities in the regulation of signaling events. Sequence and structural alignments pointed to two interaction hotspots in the RA/RB domains, consisting of an average of 19 RAS-binding residues. Moreover, we found novel interactions between RRAS1, RIT1, and RALA and RASSF7, RASSF9, and RASSF1, respectively, which were systematically explored in sequence–structure–property relationship analysis, and validated by mutational analysis. These data provide a set of distinct functional properties and putative biological roles that should now be investigated in the cellular context.
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Affiliation(s)
- Soheila Rezaei Adariani
- Medical Faculty, Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, Düsseldorf, Germany
| | - Neda S Kazemein Jasemi
- Medical Faculty, Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, Düsseldorf, Germany
| | - Farhad Bazgir
- Medical Faculty, Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, Düsseldorf, Germany
| | - Christoph Wittich
- Medical Faculty, Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, Düsseldorf, Germany
| | - Ehsan Amin
- Medical Faculty, Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, Düsseldorf, Germany; Medical Faculty, Institute of Neural and Sensory Physiology, Heinrich Heine University, Düsseldorf, Germany
| | - Claus A M Seidel
- Chair of Molecular Physical Chemistry, Heinrich Heine University, Düsseldorf, Germany
| | - Radovan Dvorsky
- Medical Faculty, Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, Düsseldorf, Germany
| | - Mohammad R Ahmadian
- Medical Faculty, Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, Düsseldorf, Germany.
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16
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Taha MS, Haghighi F, Stefanski A, Nakhaei-Rad S, Kazemein Jasemi NS, Al Kabbani MA, Görg B, Fujii M, Lang PA, Häussinger D, Piekorz RP, Stühler K, Ahmadian MR. Novel FMRP interaction networks linked to cellular stress. FEBS J 2020; 288:837-860. [PMID: 32525608 DOI: 10.1111/febs.15443] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 04/09/2020] [Accepted: 06/03/2020] [Indexed: 12/12/2022]
Abstract
Silencing of the fragile X mental retardation 1 (FMR1) gene and consequently lack of synthesis of FMR protein (FMRP) are associated with fragile X syndrome, which is one of the most prevalent inherited intellectual disabilities, with additional roles in increased viral infection, liver disease, and reduced cancer risk. FMRP plays critical roles in chromatin dynamics, RNA binding, mRNA transport, and mRNA translation. However, the underlying molecular mechanisms, including the (sub)cellular FMRP protein networks, remain elusive. Here, we employed affinity pull-down and quantitative LC-MS/MS analyses with FMRP. We identified known and novel candidate FMRP-binding proteins as well as protein complexes. FMRP interacted with 180 proteins, 28 of which interacted with its N terminus. Interaction with the C terminus of FMRP was observed for 102 proteins, and 48 proteins interacted with both termini. This FMRP interactome comprises known FMRP-binding proteins, including the ribosomal proteins FXR1P, NUFIP2, Caprin-1, and numerous novel FMRP candidate interacting proteins that localize to different subcellular compartments, including CARF, LARP1, LEO1, NOG2, G3BP1, NONO, NPM1, SKIP, SND1, SQSTM1, and TRIM28. Our data considerably expand the protein and RNA interaction networks of FMRP, which thereby suggest that, in addition to its known functions, FMRP participates in transcription, RNA metabolism, ribonucleoprotein stress granule formation, translation, DNA damage response, chromatin dynamics, cell cycle regulation, ribosome biogenesis, miRNA biogenesis, and mitochondrial organization. Thus, FMRP seems associated with multiple cellular processes both under normal and cell stress conditions in neuronal as well as non-neuronal cell types, as exemplified by its role in the formation of stress granules.
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Affiliation(s)
- Mohamed S Taha
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany.,Research on Children with Special Needs Department, Medical Research Branch, National Research Centre, Cairo, Egypt
| | - Fereshteh Haghighi
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany
| | - Anja Stefanski
- Molecular Proteomics Laboratory, Heinrich Heine-University, Düsseldorf, Germany
| | - Saeideh Nakhaei-Rad
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany
| | - Neda S Kazemein Jasemi
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany
| | - Mohamed Aghyad Al Kabbani
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany
| | - Boris Görg
- Clinic of Gastroenterology, Hepatology and Infectious Diseases, Medical Faculty of the Heinrich Heine-University, Düsseldorf, Germany
| | - Masahiro Fujii
- Division of Virology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Phillip A Lang
- Department of Molecular Medicine II, Medical Faculty, Heinrich Heine-University, Düsseldorf, Germany
| | - Dieter Häussinger
- Clinic of Gastroenterology, Hepatology and Infectious Diseases, Medical Faculty of the Heinrich Heine-University, Düsseldorf, Germany
| | - Roland P Piekorz
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany
| | - Kai Stühler
- Molecular Proteomics Laboratory, Heinrich Heine-University, Düsseldorf, Germany
| | - Mohammad R Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany
| |
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17
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Lam MT, Coppola S, Krumbach OHF, Prencipe G, Insalaco A, Cifaldi C, Brigida I, Zara E, Scala S, Di Cesare S, Martinelli S, Di Rocco M, Pascarella A, Niceta M, Pantaleoni F, Ciolfi A, Netter P, Carisey AF, Diehl M, Akbarzadeh M, Conti F, Merli P, Pastore A, Levi Mortera S, Camerini S, Farina L, Buchholzer M, Pannone L, Cao TN, Coban-Akdemir ZH, Jhangiani SN, Muzny DM, Gibbs RA, Basso-Ricci L, Chiriaco M, Dvorsky R, Putignani L, Carsetti R, Janning P, Stray-Pedersen A, Erichsen HC, Horne A, Bryceson YT, Torralba-Raga L, Ramme K, Rosti V, Bracaglia C, Messia V, Palma P, Finocchi A, Locatelli F, Chinn IK, Lupski JR, Mace EM, Cancrini C, Aiuti A, Ahmadian MR, Orange JS, De Benedetti F, Tartaglia M. A novel disorder involving dyshematopoiesis, inflammation, and HLH due to aberrant CDC42 function. J Exp Med 2019. [PMID: 31601675 DOI: 10.1084/jem.20190147)] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Hemophagocytic lymphohistiocytosis (HLH) is characterized by immune dysregulation due to inadequate restraint of overactivated immune cells and is associated with a variable clinical spectrum having overlap with more common pathophysiologies. HLH is difficult to diagnose and can be part of inflammatory syndromes. Here, we identify a novel hematological/autoinflammatory condition (NOCARH syndrome) in four unrelated patients with superimposable features, including neonatal-onset cytopenia with dyshematopoiesis, autoinflammation, rash, and HLH. Patients shared the same de novo CDC42 mutation (Chr1:22417990C>T, p.R186C) and altered hematopoietic compartment, immune dysregulation, and inflammation. CDC42 mutations had been associated with syndromic neurodevelopmental disorders. In vitro and in vivo assays documented unique effects of p.R186C on CDC42 localization and function, correlating with the distinctiveness of the trait. Emapalumab was critical to the survival of one patient, who underwent successful bone marrow transplantation. Early recognition of the disorder and establishment of treatment followed by bone marrow transplant are important to survival.
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Affiliation(s)
- Michael T Lam
- Department of Pediatrics, Baylor College of Medicine, Houston, TX.,Department of Pediatrics, Columbia University, Irving Medical Center, New York, NY.,Medical Scientist Training Program and Translational Biology and Molecular Medicine Graduate Program, Baylor College of Medicine, Houston, TX
| | - Simona Coppola
- National Center for Rare Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Oliver H F Krumbach
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, Düsseldorf, Germany
| | - Giusi Prencipe
- Immunology Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Antonella Insalaco
- Immunology Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Cristina Cifaldi
- Academic Department of Pediatrics, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy.,Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Immacolata Brigida
- San Raffaele Telethon Institute for Gene Therapy, Istituto di Ricovero e Cura a Carattere Scientifico San Raffaele Scientific Institute, Milan, Italy
| | - Erika Zara
- National Center for Rare Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Serena Scala
- San Raffaele Telethon Institute for Gene Therapy, Istituto di Ricovero e Cura a Carattere Scientifico San Raffaele Scientific Institute, Milan, Italy
| | - Silvia Di Cesare
- Academic Department of Pediatrics, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy.,Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Simone Martinelli
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Martina Di Rocco
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy.,Department of Cellular Biotechnology and Haematology, Sapienza University of Rome, Rome, Italy
| | - Antonia Pascarella
- Immunology Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Marcello Niceta
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Francesca Pantaleoni
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Andrea Ciolfi
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Petra Netter
- Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Alexandre F Carisey
- Department of Pediatrics, Baylor College of Medicine, Houston, TX.,Department of Pediatrics, Columbia University, Irving Medical Center, New York, NY
| | - Michael Diehl
- Department of Bioengineering, Rice University, Houston, TX
| | - Mohammad Akbarzadeh
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, Düsseldorf, Germany
| | - Francesca Conti
- Academic Department of Pediatrics, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Pietro Merli
- Department of Pediatric Hematology and Oncology, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Anna Pastore
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Stefano Levi Mortera
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Serena Camerini
- Core Facilities, Italian National Institute of Health, Rome, Italy
| | - Luciapia Farina
- National Center for Rare Diseases, Istituto Superiore di Sanità, Rome, Italy.,Immunology Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Marcel Buchholzer
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, Düsseldorf, Germany
| | - Luca Pannone
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy.,Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Tram N Cao
- Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Zeynep H Coban-Akdemir
- Baylor-Hopkins Center for Mendelian Genomics, Houston, TX.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX
| | - Shalini N Jhangiani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX.,Human Genome Sequencing Center of Baylor College of Medicine, Houston, TX
| | - Donna M Muzny
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX.,Human Genome Sequencing Center of Baylor College of Medicine, Houston, TX
| | - Richard A Gibbs
- Baylor-Hopkins Center for Mendelian Genomics, Houston, TX.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX.,Human Genome Sequencing Center of Baylor College of Medicine, Houston, TX
| | - Luca Basso-Ricci
- San Raffaele Telethon Institute for Gene Therapy, Istituto di Ricovero e Cura a Carattere Scientifico San Raffaele Scientific Institute, Milan, Italy
| | - Maria Chiriaco
- Academic Department of Pediatrics, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Radovan Dvorsky
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, Düsseldorf, Germany
| | - Lorenza Putignani
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Rita Carsetti
- Immunology Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Petra Janning
- Department of Chemical Biology, Max-Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Asbjorg Stray-Pedersen
- Baylor-Hopkins Center for Mendelian Genomics, Houston, TX.,Norwegian National Unit for Newborn Screening, Department of Pediatric and Adolescent Medicine, Oslo University Hospital, Oslo, Norway.,Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | | | - AnnaCarin Horne
- Pediatric Rheumatology, Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden.,Department of Women's and Children's Health, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden
| | - Yenan T Bryceson
- Department of Medicine, Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm, Sweden.,Broegelmann Research Laboratory, Institute of Clinical Sciences, University of Bergen, Bergen, Norway
| | - Lamberto Torralba-Raga
- Department of Medicine, Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Kim Ramme
- Pediatric Hematology, Immunology and HCT Section, Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden
| | - Vittorio Rosti
- Center for Myelofibrosis, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy
| | - Claudia Bracaglia
- Immunology Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Virginia Messia
- Immunology Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Paolo Palma
- Academic Department of Pediatrics, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Andrea Finocchi
- Academic Department of Pediatrics, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy.,Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Franco Locatelli
- Department of Pediatric Hematology and Oncology, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy.,Department of Pediatrics, Sapienza University of Rome, Italy
| | - Ivan K Chinn
- Department of Pediatrics, Baylor College of Medicine, Houston, TX.,Division of Pediatric Immunology, Allergy, Rheumatology, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - James R Lupski
- Department of Pediatrics, Baylor College of Medicine, Houston, TX.,Baylor-Hopkins Center for Mendelian Genomics, Houston, TX.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX.,Human Genome Sequencing Center of Baylor College of Medicine, Houston, TX
| | - Emily M Mace
- Department of Pediatrics, Columbia University, Irving Medical Center, New York, NY
| | - Caterina Cancrini
- Academic Department of Pediatrics, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy.,Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Alessandro Aiuti
- San Raffaele Telethon Institute for Gene Therapy, Istituto di Ricovero e Cura a Carattere Scientifico San Raffaele Scientific Institute, Milan, Italy.,Pediatric Immunohematology, San Raffaele Scientific Institute, Milan, Italy.,Vita Salute San Raffaele University, Milan, Italy
| | - Mohammad R Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, Düsseldorf, Germany
| | - Jordan S Orange
- Department of Pediatrics, Columbia University, Irving Medical Center, New York, NY .,Medical Scientist Training Program and Translational Biology and Molecular Medicine Graduate Program, Baylor College of Medicine, Houston, TX
| | - Fabrizio De Benedetti
- Immunology Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Marco Tartaglia
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| |
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18
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Lam MT, Coppola S, Krumbach OHF, Prencipe G, Insalaco A, Cifaldi C, Brigida I, Zara E, Scala S, Di Cesare S, Martinelli S, Di Rocco M, Pascarella A, Niceta M, Pantaleoni F, Ciolfi A, Netter P, Carisey AF, Diehl M, Akbarzadeh M, Conti F, Merli P, Pastore A, Levi Mortera S, Camerini S, Farina L, Buchholzer M, Pannone L, Cao TN, Coban-Akdemir ZH, Jhangiani SN, Muzny DM, Gibbs RA, Basso-Ricci L, Chiriaco M, Dvorsky R, Putignani L, Carsetti R, Janning P, Stray-Pedersen A, Erichsen HC, Horne A, Bryceson YT, Torralba-Raga L, Ramme K, Rosti V, Bracaglia C, Messia V, Palma P, Finocchi A, Locatelli F, Chinn IK, Lupski JR, Mace EM, Cancrini C, Aiuti A, Ahmadian MR, Orange JS, De Benedetti F, Tartaglia M. A novel disorder involving dyshematopoiesis, inflammation, and HLH due to aberrant CDC42 function. J Exp Med 2019; 216:2778-2799. [PMID: 31601675 PMCID: PMC6888978 DOI: 10.1084/jem.20190147] [Citation(s) in RCA: 121] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 04/19/2019] [Accepted: 08/06/2019] [Indexed: 12/27/2022] Open
Abstract
Lam et al. characterize a novel hematological/autoinflammatory disorder due to a de novo recurrent missense mutation of CDC42. The authors use in silico, in vitro, and in vivo analyses to correlate the molecular mechanisms altering CDC42 function to the observed phenotype. Hemophagocytic lymphohistiocytosis (HLH) is characterized by immune dysregulation due to inadequate restraint of overactivated immune cells and is associated with a variable clinical spectrum having overlap with more common pathophysiologies. HLH is difficult to diagnose and can be part of inflammatory syndromes. Here, we identify a novel hematological/autoinflammatory condition (NOCARH syndrome) in four unrelated patients with superimposable features, including neonatal-onset cytopenia with dyshematopoiesis, autoinflammation, rash, and HLH. Patients shared the same de novo CDC42 mutation (Chr1:22417990C>T, p.R186C) and altered hematopoietic compartment, immune dysregulation, and inflammation. CDC42 mutations had been associated with syndromic neurodevelopmental disorders. In vitro and in vivo assays documented unique effects of p.R186C on CDC42 localization and function, correlating with the distinctiveness of the trait. Emapalumab was critical to the survival of one patient, who underwent successful bone marrow transplantation. Early recognition of the disorder and establishment of treatment followed by bone marrow transplant are important to survival.
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Affiliation(s)
- Michael T Lam
- Department of Pediatrics, Baylor College of Medicine, Houston, TX.,Department of Pediatrics, Columbia University, Irving Medical Center, New York, NY.,Medical Scientist Training Program and Translational Biology and Molecular Medicine Graduate Program, Baylor College of Medicine, Houston, TX
| | - Simona Coppola
- National Center for Rare Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Oliver H F Krumbach
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, Düsseldorf, Germany
| | - Giusi Prencipe
- Immunology Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Antonella Insalaco
- Immunology Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Cristina Cifaldi
- Academic Department of Pediatrics, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy.,Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Immacolata Brigida
- San Raffaele Telethon Institute for Gene Therapy, Istituto di Ricovero e Cura a Carattere Scientifico San Raffaele Scientific Institute, Milan, Italy
| | - Erika Zara
- National Center for Rare Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Serena Scala
- San Raffaele Telethon Institute for Gene Therapy, Istituto di Ricovero e Cura a Carattere Scientifico San Raffaele Scientific Institute, Milan, Italy
| | - Silvia Di Cesare
- Academic Department of Pediatrics, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy.,Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Simone Martinelli
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Martina Di Rocco
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy.,Department of Cellular Biotechnology and Haematology, Sapienza University of Rome, Rome, Italy
| | - Antonia Pascarella
- Immunology Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Marcello Niceta
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Francesca Pantaleoni
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Andrea Ciolfi
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Petra Netter
- Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Alexandre F Carisey
- Department of Pediatrics, Baylor College of Medicine, Houston, TX.,Department of Pediatrics, Columbia University, Irving Medical Center, New York, NY
| | - Michael Diehl
- Department of Bioengineering, Rice University, Houston, TX
| | - Mohammad Akbarzadeh
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, Düsseldorf, Germany
| | - Francesca Conti
- Academic Department of Pediatrics, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Pietro Merli
- Department of Pediatric Hematology and Oncology, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Anna Pastore
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Stefano Levi Mortera
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Serena Camerini
- Core Facilities, Italian National Institute of Health, Rome, Italy
| | - Luciapia Farina
- National Center for Rare Diseases, Istituto Superiore di Sanità, Rome, Italy.,Immunology Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Marcel Buchholzer
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, Düsseldorf, Germany
| | - Luca Pannone
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy.,Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Tram N Cao
- Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Zeynep H Coban-Akdemir
- Baylor-Hopkins Center for Mendelian Genomics, Houston, TX.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX
| | - Shalini N Jhangiani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX.,Human Genome Sequencing Center of Baylor College of Medicine, Houston, TX
| | - Donna M Muzny
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX.,Human Genome Sequencing Center of Baylor College of Medicine, Houston, TX
| | - Richard A Gibbs
- Baylor-Hopkins Center for Mendelian Genomics, Houston, TX.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX.,Human Genome Sequencing Center of Baylor College of Medicine, Houston, TX
| | - Luca Basso-Ricci
- San Raffaele Telethon Institute for Gene Therapy, Istituto di Ricovero e Cura a Carattere Scientifico San Raffaele Scientific Institute, Milan, Italy
| | - Maria Chiriaco
- Academic Department of Pediatrics, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Radovan Dvorsky
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, Düsseldorf, Germany
| | - Lorenza Putignani
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Rita Carsetti
- Immunology Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Petra Janning
- Department of Chemical Biology, Max-Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Asbjorg Stray-Pedersen
- Baylor-Hopkins Center for Mendelian Genomics, Houston, TX.,Norwegian National Unit for Newborn Screening, Department of Pediatric and Adolescent Medicine, Oslo University Hospital, Oslo, Norway.,Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | | | - AnnaCarin Horne
- Pediatric Rheumatology, Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden.,Department of Women's and Children's Health, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden
| | - Yenan T Bryceson
- Department of Medicine, Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm, Sweden.,Broegelmann Research Laboratory, Institute of Clinical Sciences, University of Bergen, Bergen, Norway
| | - Lamberto Torralba-Raga
- Department of Medicine, Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Kim Ramme
- Pediatric Hematology, Immunology and HCT Section, Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden
| | - Vittorio Rosti
- Center for Myelofibrosis, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy
| | - Claudia Bracaglia
- Immunology Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Virginia Messia
- Immunology Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Paolo Palma
- Academic Department of Pediatrics, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Andrea Finocchi
- Academic Department of Pediatrics, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy.,Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Franco Locatelli
- Department of Pediatric Hematology and Oncology, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy.,Department of Pediatrics, Sapienza University of Rome, Italy
| | - Ivan K Chinn
- Department of Pediatrics, Baylor College of Medicine, Houston, TX.,Division of Pediatric Immunology, Allergy, Rheumatology, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - James R Lupski
- Department of Pediatrics, Baylor College of Medicine, Houston, TX.,Baylor-Hopkins Center for Mendelian Genomics, Houston, TX.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX.,Human Genome Sequencing Center of Baylor College of Medicine, Houston, TX
| | - Emily M Mace
- Department of Pediatrics, Columbia University, Irving Medical Center, New York, NY
| | - Caterina Cancrini
- Academic Department of Pediatrics, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy.,Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Alessandro Aiuti
- San Raffaele Telethon Institute for Gene Therapy, Istituto di Ricovero e Cura a Carattere Scientifico San Raffaele Scientific Institute, Milan, Italy.,Pediatric Immunohematology, San Raffaele Scientific Institute, Milan, Italy.,Vita Salute San Raffaele University, Milan, Italy
| | - Mohammad R Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, Düsseldorf, Germany
| | - Jordan S Orange
- Department of Pediatrics, Columbia University, Irving Medical Center, New York, NY .,Medical Scientist Training Program and Translational Biology and Molecular Medicine Graduate Program, Baylor College of Medicine, Houston, TX
| | - Fabrizio De Benedetti
- Immunology Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Marco Tartaglia
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
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19
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Capri Y, Flex E, Krumbach OH, Carpentieri G, Cecchetti S, Lißewski C, Rezaei Adariani S, Schanze D, Brinkmann J, Piard J, Pantaleoni F, Lepri FR, Goh ESY, Chong K, Stieglitz E, Meyer J, Kuechler A, Bramswig NC, Sacharow S, Strullu M, Vial Y, Vignal C, Kensah G, Cuturilo G, Kazemein Jasemi NS, Dvorsky R, Monaghan KG, Vincent LM, Cavé H, Verloes A, Ahmadian MR, Tartaglia M, Zenker M. Activating Mutations of RRAS2 Are a Rare Cause of Noonan Syndrome. Am J Hum Genet 2019; 104:1223-1232. [PMID: 31130282 DOI: 10.1016/j.ajhg.2019.04.013] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 04/18/2019] [Indexed: 01/18/2023] Open
Abstract
Aberrant signaling through pathways controlling cell response to extracellular stimuli constitutes a central theme in disorders affecting development. Signaling through RAS and the MAPK cascade controls a variety of cell decisions in response to cytokines, hormones, and growth factors, and its upregulation causes Noonan syndrome (NS), a developmental disorder whose major features include a distinctive facies, a wide spectrum of cardiac defects, short stature, variable cognitive impairment, and predisposition to malignancies. NS is genetically heterogeneous, and mutations in more than ten genes have been reported to underlie this disorder. Despite the large number of genes implicated, about 10%-20% of affected individuals with a clinical diagnosis of NS do not have mutations in known RASopathy-associated genes, indicating that additional unidentified genes contribute to the disease, when mutated. By using a mixed strategy of functional candidacy and exome sequencing, we identify RRAS2 as a gene implicated in NS in six unrelated subjects/families. We show that the NS-causing RRAS2 variants affect highly conserved residues localized around the nucleotide binding pocket of the GTPase and are predicted to variably affect diverse aspects of RRAS2 biochemical behavior, including nucleotide binding, GTP hydrolysis, and interaction with effectors. Additionally, all pathogenic variants increase activation of the MAPK cascade and variably impact cell morphology and cytoskeletal rearrangement. Finally, we provide a characterization of the clinical phenotype associated with RRAS2 mutations.
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20
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Becker MS, Müller PM, Bajorat J, Schroeder A, Giaisi M, Amin E, Ahmadian MR, Rocks O, Köhler R, Krammer PH, Li-Weber M. The anticancer phytochemical rocaglamide inhibits Rho GTPase activity and cancer cell migration. Oncotarget 2018; 7:51908-51921. [PMID: 27340868 PMCID: PMC5239523 DOI: 10.18632/oncotarget.10188] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 06/04/2016] [Indexed: 12/29/2022] Open
Abstract
Chemotherapy is one of the pillars of anti-cancer therapy. Although chemotherapeutics cause regression of the primary tumor, many chemotherapeutics are often shown to induce or accelerate metastasis formation. Moreover, metastatic tumors are largely resistant against chemotherapy. As more than 90% of cancer patients die due to metastases and not due to primary tumor formation, novel drugs are needed to overcome these shortcomings. In this study, we identified the anticancer phytochemical Rocaglamide (Roc-A) to be an inhibitor of cancer cell migration, a crucial event in metastasis formation. We show that Roc-A inhibits cellular migration and invasion independently of its anti-proliferative and cytotoxic effects in different types of human cancer cells. Mechanistically, Roc-A treatment induces F-actin-based morphological changes in membrane protrusions. Further investigation of the molecular mechanisms revealed that Roc-A inhibits the activities of the small GTPases RhoA, Rac1 and Cdc42, the master regulators of cellular migration. Taken together, our results provide evidence that Roc-A may be a lead candidate for a new class of anticancer drugs that inhibit metastasis formation.
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Affiliation(s)
- Michael S Becker
- Tumorimmunology Program (D030), German Cancer Research Center (DKFZ), INF-280, Heidelberg, Germany
| | - Paul M Müller
- Max Delbrück Center for Molecular Medicine Berlin-Buch, Berlin, Germany
| | - Jörg Bajorat
- Tumorimmunology Program (D030), German Cancer Research Center (DKFZ), INF-280, Heidelberg, Germany
| | - Anne Schroeder
- Tumorimmunology Program (D030), German Cancer Research Center (DKFZ), INF-280, Heidelberg, Germany
| | - Marco Giaisi
- Tumorimmunology Program (D030), German Cancer Research Center (DKFZ), INF-280, Heidelberg, Germany
| | - Ehsan Amin
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of The Heinrich-Heine University, Düsseldorf, Germany
| | - Mohammad R Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of The Heinrich-Heine University, Düsseldorf, Germany
| | - Oliver Rocks
- Max Delbrück Center for Molecular Medicine Berlin-Buch, Berlin, Germany
| | - Rebecca Köhler
- Tumorimmunology Program (D030), German Cancer Research Center (DKFZ), INF-280, Heidelberg, Germany
| | - Peter H Krammer
- Tumorimmunology Program (D030), German Cancer Research Center (DKFZ), INF-280, Heidelberg, Germany
| | - Min Li-Weber
- Tumorimmunology Program (D030), German Cancer Research Center (DKFZ), INF-280, Heidelberg, Germany
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21
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Abstract
The specific and rapid formation of protein complexes, involving IQGAP family proteins, is essential for diverse cellular processes, such as adhesion, polarization, and directional migration. Although CDC42 and RAC1, prominent members of the RHO GTPase family, have been implicated in binding to and activating IQGAP1, the exact nature of this protein-protein recognition process has remained obscure. Here, we propose a mechanistic framework model that is based on a multiple-step binding process, which is a prerequisite for the dynamic functions of IQGAP1 as a scaffolding protein and a critical mechanism in temporal regulation and integration of cellular pathways.
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Affiliation(s)
- Kazem Nouri
- Institute of Biochemistry and Molecular Biology II, Medical faculty of the Heinrich-Heine University, Düsseldorf, Germany
| | - David J Timson
- School of Pharmacy and Biomolecular Sciences, University of Brighton, Huxley Building, Lewes Road, Brighton, BN2 4GJ, United Kingdom
| | - Mohammad R Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical faculty of the Heinrich-Heine University, Düsseldorf, Germany
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22
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Altmüller F, Pothula S, Annamneedi A, Nakhaei-Rad S, Montenegro-Venegas C, Pina-Fernández E, Marini C, Santos M, Schanze D, Montag D, Ahmadian MR, Stork O, Zenker M, Fejtova A. Correction: Aberrant neuronal activity-induced signaling and gene expression in a mouse model of RASopathy. PLoS Genet 2017. [PMID: 28622382 PMCID: PMC5473527 DOI: 10.1371/journal.pgen.1006843] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
[This corrects the article DOI: 10.1371/journal.pgen.1006684.].
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23
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Pantaleoni F, Lev D, Cirstea IC, Motta M, Lepri FR, Bottero L, Cecchetti S, Linger I, Paolacci S, Flex E, Novelli A, Carè A, Ahmadian MR, Stellacci E, Tartaglia M. Aberrant HRAS transcript processing underlies a distinctive phenotype within the RASopathy clinical spectrum. Hum Mutat 2017; 38:798-804. [PMID: 28390077 DOI: 10.1002/humu.23224] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Revised: 03/29/2017] [Accepted: 04/01/2017] [Indexed: 01/17/2023]
Abstract
RASopathies are a group of rare, clinically related conditions affecting development and growth, and are caused by germline mutations in genes encoding signal transducers and modulators with a role in the RAS signaling network. These disorders share facial dysmorphia, short stature, variable cognitive deficits, skeletal and cardiac defects, and a variable predisposition to malignancies. Here, we report on a de novo 10-nucleotide-long deletion in HRAS (c.481_490delGGGACCCTCT, NM_176795.4; p.Leu163ProfsTer52, NP_789765.1) affecting transcript processing as a novel event underlying a RASopathy characterized by developmental delay, intellectual disability and autistic features, distinctive coarse facies, reduced growth, and ectodermal anomalies. Molecular and biochemical studies demonstrated that the deletion promotes constitutive retention of exon IDX, which is generally skipped during HRAS transcript processing, and results in a stable and mildly hyperactive GDP/GTP-bound protein that is constitutively targeted to the plasma membrane. Our findings document a new mechanism leading to altered HRAS function that underlies a previously unappreciated phenotype within the RASopathy spectrum.
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Affiliation(s)
- Francesca Pantaleoni
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Rome, Italy
| | - Dorit Lev
- The Metabolic Neurogenetic Service, Wolfson Medical Center, Holon, Israel.,Sackler School of Medicine, Tel Aviv University, Ramat Aviv, Israel
| | - Ion C Cirstea
- Institut für Biochemie und Molekularbiologie II, Medizinische Fakultät der Heinrich-Heine Universität, Dusseldorf, Germany.,Institute of Comparative Molecular Endocrinology, Ulm University, Ulm, Germany
| | - Marialetizia Motta
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Rome, Italy
| | - Francesca Romana Lepri
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Rome, Italy
| | - Lisabianca Bottero
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Serena Cecchetti
- Dipartimento di Biologia Cellulare e Neuroscienze, Istituto Superiore di Sanità, Rome, Italy
| | - Ilan Linger
- The Metabolic Neurogenetic Service, Wolfson Medical Center, Holon, Israel.,Sackler School of Medicine, Tel Aviv University, Ramat Aviv, Israel
| | - Stefano Paolacci
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Elisabetta Flex
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Antonio Novelli
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Rome, Italy
| | - Alessandra Carè
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Mohammad R Ahmadian
- Institut für Biochemie und Molekularbiologie II, Medizinische Fakultät der Heinrich-Heine Universität, Dusseldorf, Germany
| | - Emilia Stellacci
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Marco Tartaglia
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, Rome, Italy
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24
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Nouri K, Fansa EK, Amin E, Dvorsky R, Gremer L, Willbold D, Schmitt L, Timson DJ, Ahmadian MR. IQGAP1 Interaction with RHO Family Proteins Revisited: KINETIC AND EQUILIBRIUM EVIDENCE FOR MULTIPLE DISTINCT BINDING SITES. J Biol Chem 2016; 291:26364-26376. [PMID: 27815503 PMCID: PMC5159498 DOI: 10.1074/jbc.m116.752121] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 10/27/2016] [Indexed: 11/16/2022] Open
Abstract
IQ motif-containing GTPase activating protein 1 (IQGAP1) plays a central role in the physical assembly of relevant signaling networks that are responsible for various cellular processes, including cell adhesion, polarity, and transmigration. The RHO family proteins CDC42 and RAC1 have been shown to mainly interact with the GAP-related domain (GRD) of IQGAP1. However, the role of its RASGAP C-terminal (RGCT) and C-terminal domains in the interactions with RHO proteins has remained obscure. Here, we demonstrate that IQGAP1 interactions with RHO proteins underlie a multiple-step binding mechanism: (i) a high affinity, GTP-dependent binding of RGCT to the switch regions of CDC42 or RAC1 and (ii) a very low affinity binding of GRD and a C terminus adjacent to the switch regions. These data were confirmed by phosphomimetic mutation of serine 1443 to glutamate within RGCT, which led to a significant reduction of IQGAP1 affinity for CDC42 and RAC1, clearly disclosing the critical role of RGCT for these interactions. Unlike CDC42, an extremely low affinity was determined for the RAC1-GRD interaction, suggesting that the molecular nature of IQGAP1 interaction with CDC42 partially differs from that of RAC1. Our study provides new insights into the interaction characteristics of IQGAP1 with RHO family proteins and highlights the complementary importance of kinetic and equilibrium analyses. We propose that the ability of IQGAP1 to interact with RHO proteins is based on a multiple-step binding process, which is a prerequisite for the dynamic functions of IQGAP1 as a scaffolding protein and a critical mechanism in temporal regulation and integration of IQGAP1-mediated cellular responses.
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Affiliation(s)
- Kazem Nouri
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, 40225 Düsseldorf, Germany
| | - Eyad K Fansa
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, 40225 Düsseldorf, Germany
| | - Ehsan Amin
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, 40225 Düsseldorf, Germany
| | - Radovan Dvorsky
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, 40225 Düsseldorf, Germany
| | - Lothar Gremer
- the Institute of Physical Biology, Heinrich-Heine University, 40225 Düsseldorf, Germany.,Forschungszentrum Jülich, ICS-6, 52428 Jülich, Germany
| | - Dieter Willbold
- the Institute of Physical Biology, Heinrich-Heine University, 40225 Düsseldorf, Germany.,Forschungszentrum Jülich, ICS-6, 52428 Jülich, Germany
| | - Lutz Schmitt
- the Institute of Biochemistry, Heinrich-Heine University, 40225 Düsseldorf, Germany, and
| | - David J Timson
- the School of Pharmacy and Biomolecular Sciences, University of Brighton, Huxley Building, Lewes Road, Brighton BN2 4GJ, United Kingdom
| | - Mohammad R Ahmadian
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, 40225 Düsseldorf, Germany,
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25
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Amin E, Jaiswal M, Derewenda U, Reis K, Nouri K, Koessmeier KT, Aspenström P, Somlyo AV, Dvorsky R, Ahmadian MR. Deciphering the Molecular and Functional Basis of RHOGAP Family Proteins: A SYSTEMATIC APPROACH TOWARD SELECTIVE INACTIVATION OF RHO FAMILY PROTEINS. J Biol Chem 2016; 291:20353-71. [PMID: 27481945 PMCID: PMC5034035 DOI: 10.1074/jbc.m116.736967] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 07/15/2016] [Indexed: 12/30/2022] Open
Abstract
RHO GTPase-activating proteins (RHOGAPs) are one of the major classes of regulators of the RHO-related protein family that are crucial in many cellular processes, motility, contractility, growth, differentiation, and development. Using database searches, we extracted 66 distinct human RHOGAPs, from which 57 have a common catalytic domain capable of terminating RHO protein signaling by stimulating the slow intrinsic GTP hydrolysis (GTPase) reaction. The specificity of the majority of the members of RHOGAP family is largely uncharacterized. Here, we comprehensively investigated the sequence-structure-function relationship between RHOGAPs and RHO proteins by combining our in vitro data with in silico data. The activity of 14 representatives of the RHOGAP family toward 12 RHO family proteins was determined in real time. We identified and structurally verified hot spots in the interface between RHOGAPs and RHO proteins as critical determinants for binding and catalysis. We have found that the RHOGAP domain itself is nonselective and in some cases rather inefficient under cell-free conditions. Thus, we propose that other domains of RHOGAPs confer substrate specificity and fine-tune their catalytic efficiency in cells.
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Affiliation(s)
- Ehsan Amin
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Mamta Jaiswal
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Urszula Derewenda
- the Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia 22908, and
| | - Katarina Reis
- the Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Kazem Nouri
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Katja T Koessmeier
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Pontus Aspenström
- the Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Avril V Somlyo
- the Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia 22908, and
| | - Radovan Dvorsky
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, 40225 Düsseldorf, Germany,
| | - Mohammad R Ahmadian
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, 40225 Düsseldorf, Germany,
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26
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Blaževitš O, Mideksa YG, Šolman M, Ligabue A, Ariotti N, Nakhaeizadeh H, Fansa EK, Papageorgiou AC, Wittinghofer A, Ahmadian MR, Abankwa D. Galectin-1 dimers can scaffold Raf-effectors to increase H-ras nanoclustering. Sci Rep 2016; 6:24165. [PMID: 27087647 PMCID: PMC4834570 DOI: 10.1038/srep24165] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 03/22/2016] [Indexed: 12/12/2022] Open
Abstract
Galectin-1 (Gal-1) dimers crosslink carbohydrates on cell surface receptors. Carbohydrate-derived inhibitors have been developed for cancer treatment. Intracellularly, Gal-1 was suggested to interact with the farnesylated C-terminus of Ras thus specifically stabilizing GTP-H-ras nanoscale signalling hubs in the membrane, termed nanoclusters. The latter activity may present an alternative mechanism for how overexpressed Gal-1 stimulates tumourigenesis. Here we revise the current model for the interaction of Gal-1 with H-ras. We show that it indirectly forms a complex with GTP-H-ras via a high-affinity interaction with the Ras binding domain (RBD) of Ras effectors. A computationally generated model of the Gal-1/C-Raf-RBD complex is validated by mutational analysis. Both cellular FRET as well as proximity ligation assay experiments confirm interaction of Gal-1 with Raf proteins in mammalian cells. Consistently, interference with H-rasG12V-effector interactions basically abolishes H-ras nanoclustering. In addition, an intact dimer interface of Gal-1 is required for it to positively regulate H-rasG12V nanoclustering, but negatively K-rasG12V nanoclustering. Our findings suggest stacked dimers of H-ras, Raf and Gal-1 as building blocks of GTP-H-ras-nanocluster at high Gal-1 levels. Based on our results the Gal-1/effector interface represents a potential drug target site in diseases with aberrant Ras signalling.
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Affiliation(s)
- Olga Blaževitš
- Turku Centre for Biotechnology, Åbo Akademi University, Tykistökatu 6B, 20520 Turku, Finland
| | - Yonatan G Mideksa
- Turku Centre for Biotechnology, Åbo Akademi University, Tykistökatu 6B, 20520 Turku, Finland
| | - Maja Šolman
- Turku Centre for Biotechnology, Åbo Akademi University, Tykistökatu 6B, 20520 Turku, Finland
| | - Alessio Ligabue
- Turku Centre for Biotechnology, Åbo Akademi University, Tykistökatu 6B, 20520 Turku, Finland
| | - Nicholas Ariotti
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD 4072, Australia
| | - Hossein Nakhaeizadeh
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Eyad K Fansa
- Max Planck Institute for Molecular Physiology, 44227 Dortmund, Germany
| | | | | | - Mohammad R Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Daniel Abankwa
- Turku Centre for Biotechnology, Åbo Akademi University, Tykistökatu 6B, 20520 Turku, Finland
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27
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Nakhaei-Rad S, Nakhaeizadeh H, Götze S, Kordes C, Sawitza I, Hoffmann MJ, Franke M, Schulz WA, Scheller J, Piekorz RP, Häussinger D, Ahmadian MR. The Role of Embryonic Stem Cell-expressed RAS (ERAS) in the Maintenance of Quiescent Hepatic Stellate Cells. J Biol Chem 2016; 291:8399-413. [PMID: 26884329 DOI: 10.1074/jbc.m115.700088] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Indexed: 12/11/2022] Open
Abstract
Hepatic stellate cells (HSCs) were recently identified as liver-resident mesenchymal stem cells. HSCs are activated after liver injury and involved in pivotal processes, such as liver development, immunoregulation, regeneration, and also fibrogenesis. To date, several studies have reported candidate pathways that regulate the plasticity of HSCs during physiological and pathophysiological processes. Here we analyzed the expression changes and activity of the RAS family GTPases and thereby investigated the signaling networks of quiescent HSCs versus activated HSCs. For the first time, we report that embryonic stem cell-expressed RAS (ERAS) is specifically expressed in quiescent HSCs and down-regulated during HSC activation via promoter DNA methylation. Notably, in quiescent HSCs, the high level of ERAS protein correlates with the activation of AKT, STAT3, mTORC2, and HIPPO signaling pathways and inactivation of FOXO1 and YAP. Our data strongly indicate that in quiescent HSCs, ERAS targets AKT via two distinct pathways driven by PI3Kα/δ and mTORC2, whereas in activated HSCs, RAS signaling shifts to RAF-MEK-ERK. Thus, in contrast to the reported role of ERAS in tumor cells associated with cell proliferation, our findings indicate that ERAS is important to maintain quiescence in HSCs.
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Affiliation(s)
- Saeideh Nakhaei-Rad
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty
| | | | - Silke Götze
- the Clinic of Gastroenterology, Hepatology, and Infectious Diseases, and
| | - Claus Kordes
- the Clinic of Gastroenterology, Hepatology, and Infectious Diseases, and
| | - Iris Sawitza
- the Clinic of Gastroenterology, Hepatology, and Infectious Diseases, and
| | - Michèle J Hoffmann
- the Department of Urology, Medical Faculty, Heinrich-Heine University, 40225 Düsseldorf, Germany
| | - Manuel Franke
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty
| | - Wolfgang A Schulz
- the Department of Urology, Medical Faculty, Heinrich-Heine University, 40225 Düsseldorf, Germany
| | - Jürgen Scheller
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty
| | - Roland P Piekorz
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty
| | - Dieter Häussinger
- the Clinic of Gastroenterology, Hepatology, and Infectious Diseases, and
| | - Mohammad R Ahmadian
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty,
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28
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Dütting S, Heidenreich J, Cherpokova D, Amin E, Zhang SC, Ahmadian MR, Brakebusch C, Nieswandt B. Critical off-target effects of the widely used Rac1 inhibitors NSC23766 and EHT1864 in mouse platelets. J Thromb Haemost 2015; 13:827-38. [PMID: 25628054 DOI: 10.1111/jth.12861] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 01/10/2015] [Indexed: 12/25/2022]
Abstract
BACKGROUND Platelet aggregation at sites of vascular injury is essential for normal hemostasis, but may also cause pathologic vessel occlusion. Rho GTPases are molecular switches that regulate essential cellular processes, and they have pivotal functions in the cardiovascular system. Rac1 is an important regulator of platelet cytoskeletal reorganization, and contributes to platelet activation. Rac1 inhibitors are thought to be beneficial in a wide range of therapeutic settings, and have therefore been tested in vivo for a variety of disorders. Two small-molecule inhibitors, NSC23766 and EHT1864, have been characterized in different cell types, demonstrating high specificity for Rac1 and Rac, respectively. OBJECTIVES To analyze the specificity of NSC23766 and EHT1864. METHODS Platelet function was assessed in mouse wild-type and Rac1-deficient platelets by the use of flow cytometric analysis of cellular activation and aggregometry. Platelet spreading was analyzed with differential interference contrast microscopy, and activation of effector molecules was analyzed with biochemical approaches. RESULTS NSC23766 and EHT1864 showed strong and distinct Rac1-independent effects at 100 μm in platelet function tests. Both inhibitors induced Rac1-specific inhibition of platelet spreading, but also markedly impaired agonist-induced activation of Rac1(-/-) platelets. Furthermore, glycoprotein Ib-mediated signaling was dramatically inhibited by NSC23766 in both wild-type and Rac1-deficient platelets. Importantly, these inhibitors directly affected the activation of the Rac1 effectors p21-activated kinase (PAK)1 and PAK2. CONCLUSIONS Our results reveal critical off-target effects of NSC23766 and EHT1864 at 100 μm in mammalian cells, raising questions about their utility as specific Rac1/Rac inhibitors in biochemical studies at these concentrations and possibly as therapeutic agents.
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Affiliation(s)
- S Dütting
- Department of Experimental Biomedicine, University Hospital and Rudolf Virchow Center for Experimental Biomedicine, University of Würzburg, Würzburg, Germany
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29
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Flex E, Jaiswal M, Pantaleoni F, Martinelli S, Strullu M, Fansa EK, Caye A, De Luca A, Lepri F, Dvorsky R, Pannone L, Paolacci S, Zhang SC, Fodale V, Bocchinfuso G, Rossi C, Burkitt-Wright EMM, Farrotti A, Stellacci E, Cecchetti S, Ferese R, Bottero L, Castro S, Fenneteau O, Brethon B, Sanchez M, Roberts AE, Yntema HG, Van Der Burgt I, Cianci P, Bondeson ML, Cristina Digilio M, Zampino G, Kerr B, Aoki Y, Loh ML, Palleschi A, Di Schiavi E, Carè A, Selicorni A, Dallapiccola B, Cirstea IC, Stella L, Zenker M, Gelb BD, Cavé H, Ahmadian MR, Tartaglia M. Activating mutations in RRAS underlie a phenotype within the RASopathy spectrum and contribute to leukaemogenesis. Hum Mol Genet 2014; 23:4315-27. [PMID: 24705357 PMCID: PMC4103678 DOI: 10.1093/hmg/ddu148] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 03/04/2014] [Indexed: 12/29/2022] Open
Abstract
RASopathies, a family of disorders characterized by cardiac defects, defective growth, facial dysmorphism, variable cognitive deficits and predisposition to certain malignancies, are caused by constitutional dysregulation of RAS signalling predominantly through the RAF/MEK/ERK (MAPK) cascade. We report on two germline mutations (p.Gly39dup and p.Val55Met) in RRAS, a gene encoding a small monomeric GTPase controlling cell adhesion, spreading and migration, underlying a rare (2 subjects among 504 individuals analysed) and variable phenotype with features partially overlapping Noonan syndrome, the most common RASopathy. We also identified somatic RRAS mutations (p.Gly39dup and p.Gln87Leu) in 2 of 110 cases of non-syndromic juvenile myelomonocytic leukaemia, a childhood myeloproliferative/myelodysplastic disease caused by upregulated RAS signalling, defining an atypical form of this haematological disorder rapidly progressing to acute myeloid leukaemia. Two of the three identified mutations affected known oncogenic hotspots of RAS genes and conferred variably enhanced RRAS function and stimulus-dependent MAPK activation. Expression of an RRAS mutant homolog in Caenorhabditis elegans enhanced RAS signalling and engendered protruding vulva, a phenotype previously linked to the RASopathy-causing SHOC2(S2G) mutant. Overall, these findings provide evidence of a functional link between RRAS and MAPK signalling and reveal an unpredicted role of enhanced RRAS function in human disease.
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Affiliation(s)
- Elisabetta Flex
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare and
| | - Mamta Jaiswal
- Institut für Biochemie und Molekularbiologie II, Medizinische Fakultät der Heinrich-Heine Universitat, Düsseldorf 40225, Germany
| | | | | | - Marion Strullu
- Genetics Department, INSERM UMR_S940, Institut Universitaire D'Hématologie (IUH), Université Paris-Diderot Sorbonne-Paris-Cité, Paris 75010, France
| | - Eyad K Fansa
- Institut für Biochemie und Molekularbiologie II, Medizinische Fakultät der Heinrich-Heine Universitat, Düsseldorf 40225, Germany
| | - Aurélie Caye
- Genetics Department, INSERM UMR_S940, Institut Universitaire D'Hématologie (IUH), Université Paris-Diderot Sorbonne-Paris-Cité, Paris 75010, France
| | - Alessandro De Luca
- Laboratorio Mendel, Istituto di Ricovero e Cura a Carattere Scientifico-Casa Sollievo Della Sofferenza, Rome 00198, Italy
| | | | - Radovan Dvorsky
- Institut für Biochemie und Molekularbiologie II, Medizinische Fakultät der Heinrich-Heine Universitat, Düsseldorf 40225, Germany
| | - Luca Pannone
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare and
| | | | - Si-Cai Zhang
- Institut für Biochemie und Molekularbiologie II, Medizinische Fakultät der Heinrich-Heine Universitat, Düsseldorf 40225, Germany
| | | | - Gianfranco Bocchinfuso
- Dipartimento di Scienze e Tecnologie Chimiche, Università 'Tor Vergata', Rome 00133, Italy
| | - Cesare Rossi
- UO Genetica Medica, Policlinico S.Orsola-Malpighi, Bologna 40138, Italy
| | - Emma M M Burkitt-Wright
- Genetic Medicine, Academic Health Science Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester M13 9WL, UK
| | - Andrea Farrotti
- Dipartimento di Scienze e Tecnologie Chimiche, Università 'Tor Vergata', Rome 00133, Italy
| | | | - Serena Cecchetti
- Dipartimento di Biologia Cellulare e Neuroscienze, Istituto Superiore di Sanità, Rome 00161, Italy
| | - Rosangela Ferese
- Laboratorio Mendel, Istituto di Ricovero e Cura a Carattere Scientifico-Casa Sollievo Della Sofferenza, Rome 00198, Italy
| | | | - Silvana Castro
- Istituto di Genetica e Biofisica 'A. Buzzati Traverso', Consiglio Nazionale Delle Ricerche, Naples 80131, Italy
| | | | - Benoît Brethon
- Pediatric Hematology Department, Robert Debré Hospital, Paris 75019, France
| | - Massimo Sanchez
- Dipartimento di Biologia Cellulare e Neuroscienze, Istituto Superiore di Sanità, Rome 00161, Italy
| | - Amy E Roberts
- Department of Cardiology and Division of Genetics, and Department of Medicine, Boston Children's Hospital, Boston, MA 02115, USA
| | - Helger G Yntema
- Department of Human Genetics, Radboud University Medical Centre, and Nijmegen Centre for Molecular Life Sciences, Radboud University, Nijmegen 6500, The Netherlands
| | - Ineke Van Der Burgt
- Department of Human Genetics, Radboud University Medical Centre, and Nijmegen Centre for Molecular Life Sciences, Radboud University, Nijmegen 6500, The Netherlands
| | - Paola Cianci
- Genetica Clinica Pediatrica, Clinica Pediatrica Università Milano Bicocca, Fondazione MBBM, A.O. S. Gerardo, Monza 20900, Italy
| | - Marie-Louise Bondeson
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala 75237, Sweden
| | | | - Giuseppe Zampino
- Istituto di Clinica Pediatrica, Università Cattolica del Sacro Cuore, Rome 00168, Italy
| | - Bronwyn Kerr
- Genetic Medicine, Academic Health Science Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester M13 9WL, UK
| | - Yoko Aoki
- Department of Medical Genetics, Tohoku University School of Medicine, Sendai 980-8574, Japan
| | - Mignon L Loh
- Department of Pediatrics, Benioff Children's Hospital, University of California School of Medicine, and the Helen Diller Family Comprehensive Cancer Center, San Francisco, CA, 94143, USA
| | - Antonio Palleschi
- Dipartimento di Scienze e Tecnologie Chimiche, Università 'Tor Vergata', Rome 00133, Italy
| | - Elia Di Schiavi
- Istituto di Genetica e Biofisica 'A. Buzzati Traverso', Consiglio Nazionale Delle Ricerche, Naples 80131, Italy
| | - Alessandra Carè
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare and
| | - Angelo Selicorni
- Genetica Clinica Pediatrica, Clinica Pediatrica Università Milano Bicocca, Fondazione MBBM, A.O. S. Gerardo, Monza 20900, Italy
| | | | - Ion C Cirstea
- Institut für Biochemie und Molekularbiologie II, Medizinische Fakultät der Heinrich-Heine Universitat, Düsseldorf 40225, Germany, Leibniz Institute for Age Research, Jena 07745, Germany
| | - Lorenzo Stella
- Dipartimento di Scienze e Tecnologie Chimiche, Università 'Tor Vergata', Rome 00133, Italy
| | - Martin Zenker
- Institute of Human Genetics, University Hospital of Magdeburg, Otto-von-Guericke-University, Magdeburg 39120, Germany
| | - Bruce D Gelb
- Department of Pediatrics and Department of Genetics and Department of Genomic Sciences, Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Hélène Cavé
- Genetics Department, INSERM UMR_S940, Institut Universitaire D'Hématologie (IUH), Université Paris-Diderot Sorbonne-Paris-Cité, Paris 75010, France
| | - Mohammad R Ahmadian
- Institut für Biochemie und Molekularbiologie II, Medizinische Fakultät der Heinrich-Heine Universitat, Düsseldorf 40225, Germany
| | - Marco Tartaglia
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare and
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Taha MS, Nouri K, Milroy LG, Moll JM, Herrmann C, Brunsveld L, Piekorz RP, Ahmadian MR. Subcellular fractionation and localization studies reveal a direct interaction of the fragile X mental retardation protein (FMRP) with nucleolin. PLoS One 2014; 9:e91465. [PMID: 24658146 PMCID: PMC3962360 DOI: 10.1371/journal.pone.0091465] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2013] [Accepted: 02/11/2014] [Indexed: 12/31/2022] Open
Abstract
Fragile X mental Retardation Protein (FMRP) is a well-known regulator of local translation of its mRNA targets in neurons. However, despite its ubiquitous expression, the role of FMRP remains ill-defined in other cell types. In this study we investigated the subcellular distribution of FMRP and its protein complexes in HeLa cells using confocal imaging as well as detergent-free fractionation and size exclusion protocols. We found FMRP localized exclusively to solid compartments, including cytosolic heavy and light membranes, mitochondria, nuclear membrane and nucleoli. Interestingly, FMRP was associated with nucleolin in both a high molecular weight ribosomal and translation-associated complex (≥6 MDa) in the cytosol, and a low molecular weight complex (∼200 kDa) in the nucleoli. Consistently, we identified two functional nucleolar localization signals (NoLSs) in FMRP that are responsible for a strong nucleolar colocalization of the C-terminus of FMRP with nucleolin, and a direct interaction of the N-terminus of FMRP with the arginine-glycine-glycine (RGG) domain of nucleolin. Taken together, we propose a novel mechanism by which a transient nucleolar localization of FMRP underlies a strong nucleocytoplasmic translocation, most likely in a complex with nucleolin and possibly ribosomes, in order to regulate translation of its target mRNAs.
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Affiliation(s)
- Mohamed S. Taha
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine-University, Düsseldorf, Germany
| | - Kazem Nouri
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine-University, Düsseldorf, Germany
| | - Lech G. Milroy
- Laboratory of Chemical Biology and Institute of Complex Molecular Systems, Department of Biomedical Engineering, Technische Universiteit Eindhoven, Eindhoven, the Netherlands
| | - Jens M. Moll
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine-University, Düsseldorf, Germany
| | - Christian Herrmann
- Department of Physical Chemistry I, Ruhr University Bochum, Bochum, Germany
| | - Luc Brunsveld
- Laboratory of Chemical Biology and Institute of Complex Molecular Systems, Department of Biomedical Engineering, Technische Universiteit Eindhoven, Eindhoven, the Netherlands
| | - Roland P. Piekorz
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine-University, Düsseldorf, Germany
| | - Mohammad R. Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine-University, Düsseldorf, Germany
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31
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Thakur HC, Singh M, Nagel-Steger L, Prumbaum D, Fansa EK, Gremer L, Ezzahoini H, Abts A, Schmitt L, Raunser S, Ahmadian MR, Piekorz RP. Role of centrosomal adaptor proteins of the TACC family in the regulation of microtubule dynamics during mitotic cell division. Biol Chem 2014; 394:1411-23. [PMID: 23787465 DOI: 10.1515/hsz-2013-0184] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 06/18/2013] [Indexed: 02/04/2023]
Abstract
During the mitotic division cycle, cells pass through an extensive microtubule rearrangement process where microtubules forming the mitotic spindle apparatus are dynamically instable. Several centrosomal- and microtubule-associated proteins are involved in the regulation of microtubule dynamics and stability during mitosis. Here, we focus on members of the transforming acidic coiled coil (TACC) family of centrosomal adaptor proteins, in particular TACC3, in which their subcellular localization at the mitotic spindle apparatus is controlled by Aurora-A kinase-mediated phosphorylation. At the effector level, several TACC-binding partners have been identified and characterized in greater detail, in particular, the microtubule polymerase XMAP215/ch-TOG/CKAP5 and clathrin heavy chain (CHC). We summarize the recent progress in the molecular understanding of these TACC3 protein complexes, which are crucial for proper mitotic spindle assembly and dynamics to prevent faulty cell division and aneuploidy. In this regard, the (patho)biological role of TACC3 in development and cancer will be discussed.
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32
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Amin E, Dubey BN, Zhang SC, Gremer L, Dvorsky R, Moll JM, Taha MS, Nagel-Steger L, Piekorz RP, Somlyo AV, Ahmadian MR. Rho-kinase: regulation, (dys)function, and inhibition. Biol Chem 2014; 394:1399-410. [PMID: 23950574 DOI: 10.1515/hsz-2013-0181] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Accepted: 08/09/2013] [Indexed: 01/08/2023]
Abstract
In a variety of normal and pathological cell types, Rho-kinases I and II (ROCKI/II) play a pivotal role in the organization of the nonmuscle and smooth muscle cytoskeleton and adhesion plaques as well as in the regulation of transcription factors. Thus, ROCKI/II activity regulates cellular contraction, motility, morphology, polarity, cell division, and gene expression. Emerging evidence suggests that dysregulation of the Rho-ROCK pathways at different stages is linked to cardiovascular, metabolic, and neurodegenerative diseases as well as cancer. This review focuses on the current status of understanding the multiple functions of Rho-ROCK signaling pathways and various modes of regulation of Rho-ROCK activity, thereby orchestrating a concerted functional response.
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33
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Jaiswal M, Dvorsky R, Amin E, Risse SL, Fansa EK, Zhang SC, Taha MS, Gauhar AR, Nakhaei-Rad S, Kordes C, Koessmeier KT, Cirstea IC, Olayioye MA, Häussinger D, Ahmadian MR. Functional cross-talk between ras and rho pathways: a Ras-specific GTPase-activating protein (p120RasGAP) competitively inhibits the RhoGAP activity of deleted in liver cancer (DLC) tumor suppressor by masking the catalytic arginine finger. J Biol Chem 2014; 289:6839-6849. [PMID: 24443565 DOI: 10.1074/jbc.m113.527655] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The three deleted in liver cancer genes (DLC1-3) encode Rho-specific GTPase-activating proteins (RhoGAPs). Their expression is frequently silenced in a variety of cancers. The RhoGAP activity, which is required for full DLC-dependent tumor suppressor activity, can be inhibited by the Src homology 3 (SH3) domain of a Ras-specific GAP (p120RasGAP). Here, we comprehensively investigated the molecular mechanism underlying cross-talk between two distinct regulators of small GTP-binding proteins using structural and biochemical methods. We demonstrate that only the SH3 domain of p120 selectively inhibits the RhoGAP activity of all three DLC isoforms as compared with a large set of other representative SH3 or RhoGAP proteins. Structural and mutational analyses provide new insights into a putative interaction mode of the p120 SH3 domain with the DLC1 RhoGAP domain that is atypical and does not follow the classical PXXP-directed interaction. Hence, p120 associates with the DLC1 RhoGAP domain by targeting the catalytic arginine finger and thus by competitively and very potently inhibiting RhoGAP activity. The novel findings of this study shed light on the molecular mechanisms underlying the DLC inhibitory effects of p120 and suggest a functional cross-talk between Ras and Rho proteins at the level of regulatory proteins.
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Affiliation(s)
- Mamta Jaiswal
- Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, 40225 Düsseldorf
| | - Radovan Dvorsky
- Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, 40225 Düsseldorf
| | - Ehsan Amin
- Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, 40225 Düsseldorf
| | - Sarah L Risse
- Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, 40225 Düsseldorf
| | - Eyad K Fansa
- Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, 40225 Düsseldorf
| | - Si-Cai Zhang
- Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, 40225 Düsseldorf
| | - Mohamed S Taha
- Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, 40225 Düsseldorf
| | - Aziz R Gauhar
- Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, 40225 Düsseldorf
| | - Saeideh Nakhaei-Rad
- Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, 40225 Düsseldorf
| | - Claus Kordes
- Clinic for Gastroenterology, Hepatology and Infectiology, Medical Faculty, Heinrich Heine University, 40225 Düsseldorf
| | - Katja T Koessmeier
- Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, 40225 Düsseldorf
| | - Ion C Cirstea
- Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, 40225 Düsseldorf; Leibniz Institute for Age Research, 07745 Jena
| | - Monilola A Olayioye
- Institute of Cell Biology and Immunology, University of Stuttgart, 70569 Stuttgart, Germany
| | - Dieter Häussinger
- Clinic for Gastroenterology, Hepatology and Infectiology, Medical Faculty, Heinrich Heine University, 40225 Düsseldorf
| | - Mohammad R Ahmadian
- Institute of Biochemistry and Molecular Biology II, Heinrich Heine University, 40225 Düsseldorf.
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Thakur HC, Singh M, Nagel-Steger L, Kremer J, Prumbaum D, Fansa EK, Ezzahoini H, Nouri K, Gremer L, Abts A, Schmitt L, Raunser S, Ahmadian MR, Piekorz RP. The centrosomal adaptor TACC3 and the microtubule polymerase chTOG interact via defined C-terminal subdomains in an Aurora-A kinase-independent manner. J Biol Chem 2013; 289:74-88. [PMID: 24273164 DOI: 10.1074/jbc.m113.532333] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The cancer-associated, centrosomal adaptor protein TACC3 (transforming acidic coiled-coil 3) and its direct effector, the microtubule polymerase chTOG (colonic and hepatic tumor overexpressed gene), play a crucial function in centrosome-driven mitotic spindle assembly. It is unclear how TACC3 interacts with chTOG. Here, we show that the C-terminal TACC domain of TACC3 and a C-terminal fragment adjacent to the TOG domains of chTOG mediate the interaction between these two proteins. Interestingly, the TACC domain consists of two functionally distinct subdomains, CC1 (amino acids (aa) 414-530) and CC2 (aa 530-630). Whereas CC1 is responsible for the interaction with chTOG, CC2 performs an intradomain interaction with the central repeat region of TACC3, thereby masking the TACC domain before effector binding. Contrary to previous findings, our data clearly demonstrate that Aurora-A kinase does not regulate TACC3-chTOG complex formation, indicating that Aurora-A solely functions as a recruitment factor for the TACC3-chTOG complex to centrosomes and proximal mitotic spindles. We identified with CC1 and CC2, two functionally diverse modules within the TACC domain of TACC3 that modulate and mediate, respectively, TACC3 interaction with chTOG required for spindle assembly and microtubule dynamics during mitotic cell division.
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Affiliation(s)
- Harish C Thakur
- From the Institut für Biochemie und Molekularbiologie II, Medizinische Fakultät der Heinrich-Heine-Universität, D-40225 Düsseldorf, Germany
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Abstract
Wrch1/RhoU is an atypical member of the Rho family. A major structural difference is the extended N-terminus of Wrch1 (nWrch1) containing three putative SH3 domain-binding motifs whose specificities are unknown. To define the impact of this extended region on coupling Wrch1 to cellular signaling, we analyzed in this study nWrch1 interaction with Src homology 3 (SH3) domains of different adaptor proteins. Using sedimentation and isothermal titration calorimetric (ITC) measurements, we identified isolated SH3 domains of growth factor receptor-bound protein 2 (Grb2), noncatalytic region of tyrosine kinase adaptor protein 1 (Nck1), c-Src, chicken tumor virus no. 10 (CT 10) regulator kinase 1 (Crk1), and p120 as low-affinity Wrch1-binding partners. Interestingly, under cell-based conditions, nWrch1 bound tightly to endogenous Grb2 and Nck, but not to Crk, c-Src, or p120. Consistent with this, a very tight nWrch1 interaction with full-length Grb2 and Nck1 was confirmed in vitro by ITC measurements indicating that high avidity of the adaptor proteins can compensate for the low affinity of their SH3 domains. Peptide analysis revealed that the central PxxP motif of nWrch1, which employs a minimal consensus sequence of eight amino acids with an essential arginine next to the PxxP motif, is responsible for these interactions. Thus, novel functional insights from this study suggest that multiple upstream signals may converge on Wrch1 directly through its SH3 domain-binding properties.
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Affiliation(s)
- Sarah L Risse
- Department of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich-Heine University, D-40225 Dusseldorf, Germany
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Abstract
Rho GTPases act as tightly regulated molecular switches governing a large variety of critical cellular functions. Their activity is controlled by two different biochemical reactions, the GDP/GTP exchange and the GTP hydrolysis. These very slow reactions require catalysis in cells by two kinds of regulatory proteins. While the guanine nucleotide exchange factors (GEFs) activate small GTPases by stimulating the exchange of bound GDP for the cellular abundant GTP, GTPase-activating proteins (GAPs) accelerate the intrinsic rate of GTP hydrolysis by several orders of magnitude, leading to their inactivation. There are a number of methods that can be used to characterize the specificity and activity of such regulators to understand the effect of binding on the protein structure and, ultimately, to gain insights into their biological functions. This chapter describes (1) detailed protocols for the expression and purification of Rho GTPases, of -effector-binding domains, and catalytic domains of GEFs and GAPs; (2) the preparation of nucleotide-free and fluorescent nucleotide-bound Rho GTPases; and (3) methods for monitoring the intrinsic and GEF-catalyzed nucleotide exchange, the intrinsic and GAP-stimulated GTP hydrolysis, and the effector interaction with active GTPase (three alternative approaches).
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Affiliation(s)
- Mamta Jaiswal
- Medical Faculty, Institute of Biochemistry and Molecular Biology II, Heinrich-Heine University, Düsseldorf, Germany
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Stark Z, Gillessen-Kaesbach G, Ryan MM, Cirstea IC, Gremer L, Ahmadian MR, Savarirayan R, Zenker M. Two novel germline KRAS mutations: expanding the molecular and clinical phenotype. Clin Genet 2011; 81:590-4. [PMID: 21797849 DOI: 10.1111/j.1399-0004.2011.01754.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Noonan and Cardio-facio-cutaneous (CFC) syndromes are characterized by typical dysmorphic features, cardiac defects, short stature, variable ectodermal anomalies, and intellectual disability. Both belong to the Ras/mitogen-activated protein kinase pathway group of disorders and clinical features overlap other related conditions, notably LEOPARD and Costello syndromes. KRAS mutations account for about 2% of reported Noonan and <5% of reported CFC cases. The mutation spectrum includes recurrent missense changes clustering in particular domains of the KRAS protein and conferring gain-of-function. We report three patients from two unrelated families with novel missense KRAS mutations, p.K147E and p.Y71H. Both mutations affect a residue which is highly conserved in KRAS and other RAS isoforms. One of the families includes a mother and son pair who represent the first report of a vertically transmitted KRAS mutation. In addition, the mother and son pair had peripheral neuropathy, complicated by Charcot arthropathy in the mother. An unusual phenotypic effect of the specific KRAS mutation or a coincidence of two independent disorders may be considered. KRAS mutation-associated phenotypes appear to be subject to considerable clinical heterogeneity. All three cases highlight the challenges of clinical assessment in KRAS mutation-positive patients, and the utility of molecular testing as an adjunct to diagnosis.
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Affiliation(s)
- Z Stark
- Genetic Health Services Victoria, Murdoch Children's Research Institute, Melbourne, Australia
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Cirstea IC, Kutsche K, Dvorsky R, Gremer L, Carta C, Horn D, Roberts AE, Lepri F, Merbitz-Zahradnik T, König R, Kratz CP, Pantaleoni F, Dentici ML, Joshi VA, Kucherlapati RS, Mazzanti L, Mundlos S, Patton MA, Silengo MC, Rossi C, Zampino G, Digilio C, Stuppia L, Seemanova E, Pennacchio LA, Gelb BD, Dallapiccola B, Wittinghofer A, Ahmadian MR, Tartaglia M, Zenker M. A restricted spectrum of NRAS mutations causes Noonan syndrome. Nat Genet 2009; 42:27-9. [PMID: 19966803 DOI: 10.1038/ng.497] [Citation(s) in RCA: 218] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2009] [Accepted: 10/19/2009] [Indexed: 01/09/2023]
Abstract
Noonan syndrome, a developmental disorder characterized by congenital heart defects, reduced growth, facial dysmorphism and variable cognitive deficits, is caused by constitutional dysregulation of the RAS-MAPK signaling pathway. Here we report that germline NRAS mutations conferring enhanced stimulus-dependent MAPK activation account for some cases of this disorder. These findings provide evidence for an obligate dependency on proper NRAS function in human development and growth.
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Affiliation(s)
- Ion C Cirstea
- Institute of Biochemistry and Molecular Biology II, Heinrich-Heine University Medical Center, Düsseldorf, Germany
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39
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Olsen H, ter Veld F, Herbrand U, Ahmadian MR, Kinne RKH, Wehner F. Differential Regulation of Cell Volume and Shape in Confluent Rat Hepatocytes Under Hypertonic Stress. Cell Physiol Biochem 2007; 19:259-68. [PMID: 17495466 DOI: 10.1159/000100645] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/04/2006] [Indexed: 11/19/2022] Open
Abstract
In confluent primary cultures of rat hepatocytes,hypertonic stress leads to cell shrinkage and activates non-selective cation channels as the main mechanism of regulatory cell volume increase. The process is found to employ the exocytotic insertion of channels into the plasma membrane and (in addition to PKC) PLC, tyrosine kinases and G proteins, but not PI 3-kinase are part of the signalling network. Furthermore, hypertonic stress leads to the formation of stress fibres and significantly alters the activity of RhoA, Rac and Cdc42. These latter effects, however, are likely to reflect the restoration of cell shape rather than the regulation of cell volume, both most probably converging at the level of focal adhesions and integrins.
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Affiliation(s)
- Heidrun Olsen
- Max-Planck-Institut für molekulare Physiologie, Dortmund, Germany
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40
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Affiliation(s)
- Lars Röglin
- Institut für Chemie der Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
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41
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Abstract
The conversion of guanosine triphosphate (GTP) to guanosine diphosphate (GDP) and inorganic phosphate (P(i)) by guanine nucleotide binding proteins (GNBPs) is a fundamental process in living cells and represents an important timer in intracellular signalling and transport processes. While the rate of GNBP-mediated GTP hydrolysis is intrinsically slow, direct interaction with GTPase activating proteins (GAPs) accelerates the reaction by up to five orders of magnitude in vitro. Eighteen years after the discovery of the first GAP, biochemical and structural research has been accumulating evidence that GAPs employ a much wider spectrum of chemical mechanisms than had originally been assumed, in order to regulate the chemical players on the catalytic protein-protein interaction stage.
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Affiliation(s)
- K Scheffzek
- Structural and Computational Biology Programme and Developmental Biology Programme, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany.
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42
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Hemsath L, Ahmadian MR. Fluorescence approaches for monitoring interactions of Rho GTPases with nucleotides, regulators, and effectors. Methods 2006; 37:173-82. [PMID: 16289968 DOI: 10.1016/j.ymeth.2005.05.014] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2004] [Accepted: 05/24/2005] [Indexed: 11/27/2022] Open
Abstract
To understand the manner in which biological macromolecules interact with each other, we need not only structural information, but also details of kinetics and thermodynamics of the processes involved. This is particularly important for key proteins acting in signal transduction such as the small GTPases of the Ras superfamily. The complexity of their roles is constantly increasing since a large number of GTPases have been identified and each of these in turn interacts with a variety of regulatory and signaling proteins such as GAPs, GEFs, and downstream effectors. There are a number of methods that can be used to characterize the specificity, strength, and stoichiometry of such intermolecular interactions, to understand the effect of binding on the protein structure, and, ultimately, to obtain insights into their biological functions. This article discusses the use of fluorescence spectroscopic methods, which allows real-time monitoring of ligand- and protein-protein interactions at submicromolar concentrations, and quantification of the kinetic and equilibrium constants. Fluorescently labeled guanine nucleotides serve as fluorescence reporter groups to investigate the interactions of GTPases of the Rho family (e.g., RhoA, Rac1, and Cdc42). We present examples for quantitative characterization of (i) Rac1 x GDP interaction, (ii) Cdc42-interaction with the GTPase binding domain of the Wiskott Aldrich syndrome protein (three alternative approaches), (iii) accelerated nucleotide exchange reaction of RhoA by the catalytic domains of p190RhoGEF, and (iv) intrinsic and stimulated GTP-hydrolysis reaction by the catalytic domain of p50RhoGAP.
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Affiliation(s)
- Lars Hemsath
- Max-Planck-Institut für molekulare Physiologie, Abteilung Strukturelle Biologie, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
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43
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Rose R, Weyand M, Lammers M, Ishizaki T, Ahmadian MR, Wittinghofer A. Structural and mechanistic insights into the interaction between Rho and mammalian Dia. Nature 2005; 435:513-8. [PMID: 15864301 DOI: 10.1038/nature03604] [Citation(s) in RCA: 214] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2005] [Accepted: 03/29/2005] [Indexed: 11/08/2022]
Abstract
Formins are involved in a variety of cellular processes that require the remodelling of the cytoskeleton. They contain formin homology domains FH1 and FH2, which initiate actin assembly. The Diaphanous-related formins form a subgroup that is characterized by an amino-terminal Rho GTPase-binding domain (GBD) and an FH3 domain, which bind somehow to the carboxy-terminal Diaphanous autoregulatory domain (DAD) to keep the protein in an inactive conformation. Upon binding of activated Rho proteins, the DAD is released and the ability of the formin to nucleate and elongate unbranched actin filaments is induced. Here we present the crystal structure of RhoC in complex with the regulatory N terminus of mammalian Diaphanous 1 (mDia1) containing the GBD/FH3 region, an all-helical structure with armadillo repeats. Rho uses its 'switch' regions for interacting with two subdomains of GBD/FH3. We show that the FH3 domain of mDia1 forms a stable dimer and we also identify the DAD-binding site. Although binding of Rho and DAD on the N-terminal fragment of mDia1 are mutually exclusive, their binding sites are only partially overlapping. On the basis of our results, we propose a structural model for the regulation of mDia1 by Rho and DAD.
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Affiliation(s)
- R Rose
- Max-Planck-Institute of Molecular Physiology, Department of Structural Biology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
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44
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Abstract
The neurotrophin receptor p75 induces neurotrophic and/or apoptotic signalling pathways and can also cooperate with the neurotrophic Trk receptor tyrosine kinases. Its intracellular part encloses a so-called 'death domain' with a segment similar to the wasp venom mastoparan which binds small GTPases such as Rho. To study possible interactions of p75 and Ras (and Rho) we used wild-type and mutant genes of p75 stably expressed by MDCK cells which normally have neither Trk nor p75. We found that p75 can directly bind the GTPases Ras and Rho and that the unstimulated p75 inactivates total cellular Ras through a differential influence on the dissociation of GDP and GTP from Ras and an exchange of bound Ras.GDP for free Ras.GTP. These properties of p75 could also be demonstrated in vitro and should therefore be cell type-independent. Stimulation of p75 with nerve growth factor causes Ras activation via adapter proteins known from Trk signalling and induces rapid outgrowth of cellular processes. Both inactivation and activation of Ras by p75 are controlled by the phosphorylation state of the receptor's two intracellular tyrosines. p75 also influences Rho activation and inactivation, and the combined interactions of the receptor with the two GTPases Ras and Rho can regulate neurite formation in an efficient, synergistic way.
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Affiliation(s)
- Andrea Blöchl
- Molekulare Neurobiochemie, Fakultät Chemie, Molekulare Neurobiochemie, NC7/132, Ruhr-Universität Bochum, 44780 Bochum, Germany.
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45
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Fiegen D, Haeusler LC, Blumenstein L, Herbrand U, Dvorsky R, Vetter IR, Ahmadian MR. Alternative Splicing of Rac1 Generates Rac1b, a Self-activating GTPase. J Biol Chem 2004; 279:4743-9. [PMID: 14625275 DOI: 10.1074/jbc.m310281200] [Citation(s) in RCA: 118] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Rac1b was recently identified in malignant colorectal tumors as an alternative splice variant of Rac1 containing a 19-amino acid insertion next to the switch II region. The structures of Rac1b in the GDP- and the GppNHp-bound forms, determined at a resolution of 1.75 A, reveal that the insertion induces an open switch I conformation and a highly mobile switch II. As a consequence, Rac1b has an accelerated GEF-independent GDP/GTP exchange and an impaired GTP hydrolysis, which is restored partially by GTPase-activating proteins. Interestingly, Rac1b is able to bind the GTPase-binding domain of PAK but not full-length PAK in a GTP-dependent manner, suggesting that the insertion does not completely abolish effector interaction. The presented study provides insights into the structural and biochemical mechanism of a self-activating GTPase.
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Affiliation(s)
- Dennis Fiegen
- Max-Planck-Institut für molekulare Physiologie, Abteilung Strukturelle Biologie, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
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46
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Abstract
The small guanosine triphosphate (GTP) binding protein Ras is involved in many cellular signal transduction processes leading to cell growth, differentiation and apoptosis. Mutations in ras genes are found in a large number of human tumours. GTP hydrolysis, the process that normally leads to the transition of the Ras protein from the active (GTP-bound) form to the inactive (GDP-bound) form is impaired due to these oncogenic mutations. In contrast, the GTP analogue 3,4-diaminobenzophenone(DABP)-phosphoramidate-GTP, a substrate for GTP-binding proteins, enables switching to the inactive GDP form in both wild-type and oncogenic Ras. Here we show by HPLC, mass spectrometry and NMR spectroscopy that the mechanism of this DABP-GTPase reaction is different from the physiological GTPase reaction. The gamma-phosphate group is not attacked by a nucleophilic water molecule, but rather by the aromatic amino group of the analogue, which leads to the generation of a stable cyclic diamidate product. These findings have potential implications for the development of anti-Ras drugs.
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Affiliation(s)
- R Gail
- Max-Planck-Institut für molekulare Physiologie, Abteilung Strukturelle Biologie, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
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47
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Allin C, Ahmadian MR, Wittinghofer A, Gerwert K. Monitoring the GAP catalyzed H-Ras GTPase reaction at atomic resolution in real time. Proc Natl Acad Sci U S A 2001; 98:7754-9. [PMID: 11438727 PMCID: PMC35414 DOI: 10.1073/pnas.131549798] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The molecular reaction mechanism of the GTPase-activating protein (GAP)-catalyzed GTP hydrolysis by Ras was investigated by time resolved Fourier transform infrared (FTIR) difference spectroscopy using caged GTP (P(3)-1-(2-nitro)phenylethyl guanosine 5'-O-triphosphate) as photolabile trigger. This approach provides the complete GTPase reaction pathway with time resolution of milliseconds at the atomic level. Up to now, one structural model of the GAP x Ras x GDP x AlF(x) transition state analog is known, which represents a "snap shot" along the reaction-pathway. As now revealed, binding of GAP to Ras x GTP shifts negative charge from the gamma to beta phosphate. Such a shift was already identified by FTIR in GTP because of Ras binding and is now shown to be enhanced by GAP binding. Because the charge distribution of the GAP x Ras x GTP complex thus resembles a more dissociative-like transition state and is more like that in GDP, the activation free energy is reduced. An intermediate is observed on the reaction pathway that appears when the bond between beta and gamma phosphate is cleaved. In the intermediate, the released P(i) is strongly bound to the protein and surprisingly shows bands typical of those seen for phosphorylated enzyme intermediates. All these results provide a mechanistic picture that is different from the intrinsic GTPase reaction of Ras. FTIR analysis reveals the release of P(i) from the protein complex as the rate-limiting step for the GAP-catalyzed reaction. The approach presented allows the study not only of single proteins but of protein-protein interactions without intrinsic chromophores, in the non-crystalline state, in real time at the atomic level.
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Affiliation(s)
- C Allin
- Lehrstuhl für Biophysik, Ruhr-Universität Bochum, D-44780 Bochum, Germany
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48
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Demunter A, Ahmadian MR, Libbrecht L, Stas M, Baens M, Scheffzek K, Degreef H, De Wolf-Peeters C, van Den Oord JJ. A novel N-ras mutation in malignant melanoma is associated with excellent prognosis. Cancer Res 2001; 61:4916-22. [PMID: 11406571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Mutations in the ras gene are key events in the process of carcinogenesis; in particular, point mutations in codon 61 of exon 2 of the N-ras gene occur frequently in malignant melanoma (MM). We searched for point mutations in the N-ras gene in a large series of primary and metastatic MM from 81 different retrospectively selected patients using the very sensitive denaturing gradient gel electrophoresis technique, followed by sequencing. The classical codon 12 and codon 61 mutations were found in 21 and 17% of the cases, respectively. No codon 13 mutation was found. A novel mutation at codon 18 of exon 1, consisting of a substitution of alanine (GCA) by threonine (ACA), was found in 15% of the primary MMs but in none of the metastatic MMs. All of the other cases were free of mutations. Using microdissected cells from distinctive MM growth phases as source of DNA for mutation analysis, this particular N-ras exon 1 mutation at codon 18 was already present in the radial growth phase and preserved throughout the successive growth phases; it was also found in a dysplastic nevi in continuity with a MM, indicating a clonal relationship between both lesions. Our findings also illustrate the clonal relationship between the distinctive growth phases in MM and suggest the codon 18 mutation to occur early in MM development. The MM in patients with this mutation were significantly thinner than those without a codon 18 mutation (P = 0.0257). Statistical analysis, comparing the group of codon 18 patients with the group of patients with the classical mutations and without mutations, revealed a highly significant difference in overall outcome. The cumulative probability of developing metastasis was significantly lower for the group patients with a codon 18 mutation (P = 0.0130). We can thus conclude that this codon 18 mutation identifies a group of patients with better prognosis than patients with melanoma that harbor wild-type sequence or classical activating point mutations in codon 12 or 61. Preliminary nucleotide binding measurements could not detect a difference between wild-type Ras protein and the mutant Ras(A18T) protein. However, for a precise elucidation of the role of the N-Ras(A18T) mutant in melanoma, additional studies aimed to measure the affinity to guanine nucleotide exchange factors and GTPase-activating proteins are needed.
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Affiliation(s)
- A Demunter
- Laboratory of Morphology, Department of Pathology, Katholieke Universiteit Leuven, Leuven 3000, Belgium
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49
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van Horck FP, Ahmadian MR, Haeusler LC, Moolenaar WH, Kranenburg O. Characterization of p190RhoGEF, a RhoA-specific guanine nucleotide exchange factor that interacts with microtubules. J Biol Chem 2001; 276:4948-56. [PMID: 11058585 DOI: 10.1074/jbc.m003839200] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Rho family GTPases control numerous cellular processes including cytoskeletal reorganization and transcriptional activation. Rho GTPases are activated by guanine nucleotide exchange factors (GEFs) which stimulate the exchange of bound GDP for GTP. We recently isolated a putative GEF, termed p190RhoGEF that binds to RhoA and, when overexpressed in neuronal cells, induces cell rounding and inhibits neurite outgrowth. Here we show that the isolated tandem Dbl homology/pleckstrin homology domain of p190RhoGEF activates RhoA in vitro, but not Rac1 or Cdc42, as determined by GDP release and protein binding assays. In contrast, full-length p190RhoGEF fails to activate RhoA in vitro. When overexpressed in intact cells, however, p190RhoGEF does activate RhoA with subsequent F-actin reorganization and serum response factor-mediated transcription. Immunofluorescence studies show that endogenous p190RhoGEF localizes to distinct RhoA-containing regions at the plasma membrane, to the cytosol and along microtubules. In vitro and in vivo binding experiments show that p190RhoGEF directly interacts with microtubules via its C-terminal region adjacent to the catalytic Dbl homology/pleckstrin homology domain. Our results indicate that p190RhoGEF is a specific activator of RhoA that requires as yet unknown binding partners to unmask its GDP/GTP exchange activity in vivo, and they suggest that p190RhoGEF may provide a link between microtubule dynamics and RhoA signaling.
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Affiliation(s)
- F P van Horck
- Division of Cellular Biochemistry, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
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50
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Würtele M, Wolf E, Pederson KJ, Buchwald G, Ahmadian MR, Barbieri JT, Wittinghofer A. How the Pseudomonas aeruginosa ExoS toxin downregulates Rac. Nat Struct Biol 2001; 8:23-6. [PMID: 11135665 DOI: 10.1038/83007] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Pseudomonas aeruginosa is an opportunistic bacterial pathogen. One of its major toxins, ExoS, is translocated into eukaryotic cells by a type III secretion pathway. ExoS is a dual function enzyme that affects two different Ras-related GTP binding proteins. The C-terminus inactivates Ras through ADP ribosylation, while the N-terminus inactivates Rho proteins through its GTPase activating protein (GAP) activity. Here we have determined the three-dimensional structure of a complex between Rac and the GAP domain of ExoS in the presence of GDP and AlF3. Composed of approximately 130 residues, this ExoS domain is the smallest GAP hitherto described. The GAP domain of ExoS is an all-helical protein with no obvious structural homology, and thus no recognizable evolutionary relationship, with the eukaryotic RhoGAP or RasGAP fold. Similar to other GAPs, ExoS downregulates Rac using an arginine finger to stabilize the transition state of the GTPase reaction, but the details of the ExoS-Rac interaction are unique. Considering the intrinsic resistance of P. aeruginosa to antibiotics, this might open up a new avenue towards blocking its pathogenicity.
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Affiliation(s)
- M Würtele
- Max-Planck-Institut für molekulare Physiologie, Abteilung Strukturelle Biologie, Otto-Hahn-Str. 11, 44227 Dortmund, Germany
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