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Akbarzadeh M, Flegel J, Patil S, Shang E, Narayan R, Buchholzer M, Kazemein Jasemi NS, Grigalunas M, Krzyzanowski A, Abegg D, Shuster A, Potowski M, Karatas H, Karageorgis G, Mosaddeghzadeh N, Zischinsky M, Merten C, Golz C, Brieger L, Strohmann C, Antonchick AP, Janning P, Adibekian A, Goody RS, Ahmadian MR, Ziegler S, Waldmann H. The Pseudo-Natural Product Rhonin Targets RHOGDI. Angew Chem Int Ed Engl 2022; 61:e202115193. [PMID: 35170181 PMCID: PMC9313812 DOI: 10.1002/anie.202115193] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Indexed: 11/18/2022]
Abstract
For the discovery of novel chemical matter generally endowed with bioactivity, strategies may be particularly efficient that combine previous insight about biological relevance, e.g., natural product (NP) structure, with methods that enable efficient coverage of chemical space, such as fragment-based design. We describe the de novo combination of different 5-membered NP-derived N-heteroatom fragments to structurally unprecedented "pseudo-natural products" in an efficient complexity-generating and enantioselective one-pot synthesis sequence. The pseudo-NPs inherit characteristic elements of NP structure but occupy areas of chemical space not covered by NP-derived chemotypes, and may have novel biological targets. Investigation of the pseudo-NPs in unbiased phenotypic assays and target identification led to the discovery of the first small-molecule ligand of the RHO GDP-dissociation inhibitor 1 (RHOGDI1), termed Rhonin. Rhonin inhibits the binding of the RHOGDI1 chaperone to GDP-bound RHO GTPases and alters the subcellular localization of RHO GTPases.
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Affiliation(s)
- Mohammad Akbarzadeh
- Department of Chemical BiologyMax Planck Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
- Institute of Biochemistry and Molecular Biology IIMedical Faculty and University Hospital DüsseldorfHeinrich Heine University DüsseldorfUniversitätsstrasse 1, Building 22.03.0540225DüsseldorfGermany
| | - Jana Flegel
- Department of Chemical BiologyMax Planck Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - Sumersing Patil
- Department of Chemical BiologyMax Planck Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - Erchang Shang
- Department of Chemical BiologyMax Planck Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - Rishikesh Narayan
- Department of Chemical BiologyMax Planck Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
- School of Chemical and Materials SciencesIIT Goa, FarmagudiPondaGoa-403401India
| | - Marcel Buchholzer
- Institute of Biochemistry and Molecular Biology IIMedical Faculty and University Hospital DüsseldorfHeinrich Heine University DüsseldorfUniversitätsstrasse 1, Building 22.03.0540225DüsseldorfGermany
| | - Neda S. Kazemein Jasemi
- Institute of Biochemistry and Molecular Biology IIMedical Faculty and University Hospital DüsseldorfHeinrich Heine University DüsseldorfUniversitätsstrasse 1, Building 22.03.0540225DüsseldorfGermany
| | - Michael Grigalunas
- Department of Chemical BiologyMax Planck Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - Adrian Krzyzanowski
- Department of Chemical BiologyMax Planck Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
- Faculty of Chemistry and Chemical BiologyTechnical University DortmundOtto-Hahn-Straße 644221DortmundGermany
| | - Daniel Abegg
- Department of ChemistryThe Scripps Research Institute130 Scripps WayJupiterFL 33458USA
| | - Anton Shuster
- Department of ChemistryThe Scripps Research Institute130 Scripps WayJupiterFL 33458USA
| | - Marco Potowski
- Department of Chemical BiologyMax Planck Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - Hacer Karatas
- Department of Chemical BiologyMax Planck Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - George Karageorgis
- Department of Chemical BiologyMax Planck Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - Niloufar Mosaddeghzadeh
- Institute of Biochemistry and Molecular Biology IIMedical Faculty and University Hospital DüsseldorfHeinrich Heine University DüsseldorfUniversitätsstrasse 1, Building 22.03.0540225DüsseldorfGermany
| | | | - Christian Merten
- Faculty of Chemistry and BiochemistryOrganic Chemistry IIRuhr-University BochumUniversitätsstrasse 15044780BochumGermany
| | - Christopher Golz
- Faculty of Chemistry and Chemical BiologyTechnical University DortmundOtto-Hahn-Straße 644221DortmundGermany
| | - Lucas Brieger
- Faculty of Chemistry and Chemical BiologyTechnical University DortmundOtto-Hahn-Straße 644221DortmundGermany
| | - Carsten Strohmann
- Faculty of Chemistry and Chemical BiologyTechnical University DortmundOtto-Hahn-Straße 644221DortmundGermany
| | - Andrey P. Antonchick
- Department of Chemical BiologyMax Planck Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - Petra Janning
- Department of Chemical BiologyMax Planck Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - Alexander Adibekian
- Department of ChemistryThe Scripps Research Institute130 Scripps WayJupiterFL 33458USA
| | - Roger S. Goody
- Max Planck Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - Mohammad Reza Ahmadian
- Institute of Biochemistry and Molecular Biology IIMedical Faculty and University Hospital DüsseldorfHeinrich Heine University DüsseldorfUniversitätsstrasse 1, Building 22.03.0540225DüsseldorfGermany
| | - Slava Ziegler
- Department of Chemical BiologyMax Planck Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - Herbert Waldmann
- Department of Chemical BiologyMax Planck Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
- Faculty of Chemistry and Chemical BiologyTechnical University DortmundOtto-Hahn-Straße 644221DortmundGermany
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Akbarzadeh M, Flegel J, Patil S, Shang E, Narayan R, Buchholzer M, Kazemein Jasemi NS, Grigalunas M, Krzyzanowski A, Abegg D, Shuster A, Potowski M, Karatas H, Karageorgis G, Mosaddeghzadeh N, Zischinsky M, Merten C, Golz C, Brieger L, Strohmann C, Antonchick AP, Janning P, Adibekian A, Goody RS, Ahmadian MR, Ziegler S, Waldmann H. The Pseudo‐Natural Product Rhonin Targets RHOGDI. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202115193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Mohammad Akbarzadeh
- Department of Chemical Biology Max Planck Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
- Institute of Biochemistry and Molecular Biology II Medical Faculty and University Hospital Düsseldorf Heinrich Heine University Düsseldorf Universitätsstrasse 1, Building 22.03.05 40225 Düsseldorf Germany
| | - Jana Flegel
- Department of Chemical Biology Max Planck Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Sumersing Patil
- Department of Chemical Biology Max Planck Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Erchang Shang
- Department of Chemical Biology Max Planck Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Rishikesh Narayan
- Department of Chemical Biology Max Planck Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
- School of Chemical and Materials Sciences IIT Goa, Farmagudi Ponda Goa-403401 India
| | - Marcel Buchholzer
- Institute of Biochemistry and Molecular Biology II Medical Faculty and University Hospital Düsseldorf Heinrich Heine University Düsseldorf Universitätsstrasse 1, Building 22.03.05 40225 Düsseldorf Germany
| | - Neda S. Kazemein Jasemi
- Institute of Biochemistry and Molecular Biology II Medical Faculty and University Hospital Düsseldorf Heinrich Heine University Düsseldorf Universitätsstrasse 1, Building 22.03.05 40225 Düsseldorf Germany
| | - Michael Grigalunas
- Department of Chemical Biology Max Planck Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Adrian Krzyzanowski
- Department of Chemical Biology Max Planck Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
- Faculty of Chemistry and Chemical Biology Technical University Dortmund Otto-Hahn-Straße 6 44221 Dortmund Germany
| | - Daniel Abegg
- Department of Chemistry The Scripps Research Institute 130 Scripps Way Jupiter FL 33458 USA
| | - Anton Shuster
- Department of Chemistry The Scripps Research Institute 130 Scripps Way Jupiter FL 33458 USA
| | - Marco Potowski
- Department of Chemical Biology Max Planck Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Hacer Karatas
- Department of Chemical Biology Max Planck Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - George Karageorgis
- Department of Chemical Biology Max Planck Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Niloufar Mosaddeghzadeh
- Institute of Biochemistry and Molecular Biology II Medical Faculty and University Hospital Düsseldorf Heinrich Heine University Düsseldorf Universitätsstrasse 1, Building 22.03.05 40225 Düsseldorf Germany
| | | | - Christian Merten
- Faculty of Chemistry and Biochemistry Organic Chemistry II Ruhr-University Bochum Universitätsstrasse 150 44780 Bochum Germany
| | - Christopher Golz
- Faculty of Chemistry and Chemical Biology Technical University Dortmund Otto-Hahn-Straße 6 44221 Dortmund Germany
| | - Lucas Brieger
- Faculty of Chemistry and Chemical Biology Technical University Dortmund Otto-Hahn-Straße 6 44221 Dortmund Germany
| | - Carsten Strohmann
- Faculty of Chemistry and Chemical Biology Technical University Dortmund Otto-Hahn-Straße 6 44221 Dortmund Germany
| | - Andrey P. Antonchick
- Department of Chemical Biology Max Planck Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Petra Janning
- Department of Chemical Biology Max Planck Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Alexander Adibekian
- Department of Chemistry The Scripps Research Institute 130 Scripps Way Jupiter FL 33458 USA
| | - Roger S. Goody
- Max Planck Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Mohammad Reza Ahmadian
- Institute of Biochemistry and Molecular Biology II Medical Faculty and University Hospital Düsseldorf Heinrich Heine University Düsseldorf Universitätsstrasse 1, Building 22.03.05 40225 Düsseldorf Germany
| | - Slava Ziegler
- Department of Chemical Biology Max Planck Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Herbert Waldmann
- Department of Chemical Biology Max Planck Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
- Faculty of Chemistry and Chemical Biology Technical University Dortmund Otto-Hahn-Straße 6 44221 Dortmund Germany
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Electrostatic Forces Mediate the Specificity of RHO GTPase-GDI Interactions. Int J Mol Sci 2021; 22:ijms222212493. [PMID: 34830380 PMCID: PMC8622166 DOI: 10.3390/ijms222212493] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 11/15/2021] [Accepted: 11/16/2021] [Indexed: 01/13/2023] Open
Abstract
Three decades of research have documented the spatiotemporal dynamics of RHO family GTPase membrane extraction regulated by guanine nucleotide dissociation inhibitors (GDIs), but the interplay of the kinetic mechanism and structural specificity of these interactions is as yet unresolved. To address this, we reconstituted the GDI-controlled spatial segregation of geranylgeranylated RHO protein RAC1 in vitro. Various biochemical and biophysical measurements provided unprecedented mechanistic details for GDI function with respect to RHO protein dynamics. We determined that membrane extraction of RHO GTPases by GDI occurs via a 3-step mechanism: (1) GDI non-specifically associates with the switch regions of the RHO GTPases; (2) an electrostatic switch determines the interaction specificity between the C-terminal polybasic region of RHO GTPases and two distinct negatively-charged clusters of GDI1; (3) a non-specific displacement of geranylgeranyl moiety from the membrane sequesters it into a hydrophobic cleft, effectively shielding it from the aqueous milieu. This study substantially extends the model for the mechanism of GDI-regulated RHO GTPase extraction from the membrane, and could have implications for clinical studies and drug development.
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Abstract
The development of novel fluorescence methods for the detection of key biomolecules is of great interest, both in basic research and in drug discovery. Particularly relevant and widespread molecules in cells are ADP and GDP, which are the products of a large number of cellular reactions, including reactions catalysed by nucleoside triphosphatases and kinases. Previously, biosensors for ADP were developed in this laboratory, based on fluorophore adducts with the bacterial actin homologue ParM. It is shown in the present study that one of these biosensors, tetramethylrhodamine–ParM, can also monitor GDP. The biosensor can be used to measure micromolar concentrations of GDP on the background of millimolar concentrations of GTP. The fluorescence response of the biosensor is fast, the response time being <0.2 s. Thus the biosensor allows real-time measurements of GTPase and GTP-dependent kinase reactions. Applications of the GDP biosensor are exemplified with two different GTPases, measuring the rates of GTP hydrolysis and nucleotide exchange.
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Cha B, Lim JW, Kim KH, Kim H. HSP90β interacts with Rac1 to activate NADPH oxidase in Helicobacter pylori-infected gastric epithelial cells. Int J Biochem Cell Biol 2010; 42:1455-61. [DOI: 10.1016/j.biocel.2010.04.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2010] [Revised: 04/09/2010] [Accepted: 04/28/2010] [Indexed: 10/19/2022]
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Li X, Lee AYW. Semaphorin 5A and plexin-B3 inhibit human glioma cell motility through RhoGDIalpha-mediated inactivation of Rac1 GTPase. J Biol Chem 2010; 285:32436-45. [PMID: 20696765 DOI: 10.1074/jbc.m110.120451] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Semaphorins and plexins are implicated in the progression of various types of cancer, although the molecular basis has not been fully elucidated. Here, we report the expression of plexin-B3 in glioma cells, which upon stimulation by its ligand Sema5A results in significant inhibition of cell migration and invasion. A search for the underlying mechanism revealed direct interaction of plexin-B3 with RhoGDP dissociation inhibitor α (RhoGDIα), a negative regulator of RhoGTPases that blocks guanine nucleotide exchange and sequesters them away from the plasma membrane. Glioma cells challenged with Sema5A indeed showed a marked reduction in Rac1-GTP levels by 60%, with a concomitant disruption of lamellipodia. The inactivation of Rac1 was corroborated to contribute to the impediment of glioma cell invasion by Sema5A, as supported by the abolishment of effect upon forced expression of a constitutively active Rac1 mutant. Furthermore, silencing the endogenous expression of RhoGDIα in glioma cells was found to be sufficient in abrogating the down-regulation of Rac1-GTP and the ensuing suppression of glioma cell motility induced by Sema5A. Mechanistically, we provide evidence that Sema5A promotes Rac1 recruitment to RhoGDIα and reduces its membrane localization in a plexin-B3-dependent manner, thereby preventing Rac1 activation. This represents a novel signaling of semaphorin and plexin in the control of cell motility by indirect inactivation of Rac1 through RhoGDIα.
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Affiliation(s)
- Xinhua Li
- Department of Physiology, Yong Loo Lin School of Medicine, Neurobiology/Ageing Program, Life Sciences Institute, National University of Singapore, Centre for Life Sciences, 28 Medical Drive, Singapore 117456
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Hage B, Meinel K, Baum I, Giehl K, Menke A. Rac1 activation inhibits E-cadherin-mediated adherens junctions via binding to IQGAP1 in pancreatic carcinoma cells. Cell Commun Signal 2009; 7:23. [PMID: 19737400 PMCID: PMC2745413 DOI: 10.1186/1478-811x-7-23] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2009] [Accepted: 09/08/2009] [Indexed: 12/31/2022] Open
Abstract
Background Monomeric GTPases of the Rho family control a variety of cellular functions including actin cytoskeleton organisation, cell migration and cell adhesion. Defects in these regulatory processes are involved in tumour progression and metastasis. The development of metastatic carcinoma is accompanied by deregulation of adherens junctions, which are composed of E-cadherin/β- and α-catenin complexes. Results Here, we show that the activity of the monomeric GTPase Rac1 contributes to inhibition of E-cadherin-mediated cell-cell adhesion in pancreatic carcinoma cells. Stable expression of constitutively active Rac1(V12) reduced the amount of E-cadherin on protein level in PANC-1 pancreatic carcinoma cells, whereas expression of dominant negative Rac1(N17) resulted in an increased amount of E-cadherin. Extraction of proteins associated with the actin cytoskeleton as well as coimmunoprecipitation analyses demonstrated markedly decreased amounts of E-cadherin/catenin complexes in Rac1(V12)-expressing cells, but increased amounts of functional E-cadherin/catenin complexes in cells expressing Rac1(N17). Cell aggregation and migration assays revealed, that cells containing less E-cadherin due to expression of Rac1(V12), exhibited reduced cell-cell adhesion and increased cell motility. The Rac/Cdc42 effector protein IQGAP1 has been implicated in regulating cell-cell adhesion. Coimmunoprecipitation studies showed a decrease in the association between IQGAP1 and β-catenin in Rac1(V12)-expressing PANC-1 cells and an association of IQGAP1 with Rac1(V12). Elevated association of IQGAP1 with the E-cadherin adhesion complex via β-catenin correlated with increased intercellular adhesion of PANC-1 cells. Conclusion These results indicate that active Rac1 destabilises E-cadherin-mediated cell-cell adhesion in pancreatic carcinoma cells by interacting with IQGAP1 which is associated with a disassembly of E-cadherin-mediated adherens junctions. Inhibition of Rac1 activity induced increased E-cadherin-mediated cellular adhesion.
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Affiliation(s)
- Beatrix Hage
- Internal Medicine I, University Hospital Ulm, University of Ulm, Ulm, Germany.
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8
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Ho C, Shanmugasundararaj S, Miller KW, Malinowski SA, Cook AC, Slater SJ. Interaction of anesthetics with the Rho GTPase regulator Rho GDP dissociation inhibitor. Biochemistry 2008; 47:9540-52. [PMID: 18702520 DOI: 10.1021/bi800544d] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The physiological effects of anesthetics have been ascribed to their interaction with hydrophobic sites within functionally relevant CNS proteins. Studies have shown that volatile anesthetics compete for luciferin binding to the hydrophobic substrate binding site within firefly luciferase and inhibit its activity (Franks, N. P., and Lieb, W. R. (1984) Nature 310, 599-601). To assess whether anesthetics also compete for ligand binding to a mammalian signal transduction protein, we investigated the interaction of the volatile anesthetic, halothane, with the Rho GDP dissociation inhibitor (RhoGDIalpha), which binds the geranylgeranyl moiety of GDP-bound Rho GTPases. Consistent with the existence of a discrete halothane binding site, the intrinsic tryptophan fluorescence of RhoGDIalpha was quenched by halothane (2-bromo-2-chloro-1,1,1-trifluoroethane) in a saturable, concentration-dependent manner. Bromine quenching of tryptophan fluorescence is short-range and W192 and W194 of the RhoGDIalpha are located within the geranylgeranyl binding pocket, suggesting that halothane binds within this region. Supporting this, N-acetyl-geranylgeranyl cysteine reversed tryptophan quenching by halothane. Short chain n-alcohols ( n < 6) also reversed tryptophan quenching, suggesting that RhoGDIalpha may also bind n-alkanols. Consistent with this, E193 was photolabeled by 3-azibutanol. This residue is located in the vicinity of, but outside, the geranylgeranyl chain binding pocket, suggesting that the alcohol binding site is distinct from that occupied by halothane. Supporting this, N-acetyl-geranylgeranyl cysteine enhanced E193 photolabeling by 3-azibutanol. Overall, the results suggest that halothane binds to a site within the geranylgeranyl chain binding pocket of RhoGDIalpha, whereas alcohols bind to a distal site that interacts allosterically with this pocket.
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Affiliation(s)
- Cojen Ho
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA
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Kweon SM, Cho YJ, Minoo P, Groffen J, Heisterkamp N. Activity of the Bcr GTPase-activating domain is regulated through direct protein/protein interaction with the Rho guanine nucleotide dissociation inhibitor. J Biol Chem 2007; 283:3023-3030. [PMID: 18070886 DOI: 10.1074/jbc.m705513200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The cycling of Rac GTPases, alternating between an active GTP- and an inactive GDP-bound state, is controlled by guanine nucleotide exchange factors, GTPase-activating proteins (GAPs), and guanine nucleotide dissociation inhibitors (GDIs). Little is known about how these controlling activities are coordinated. Studies using null mutant mice have demonstrated that Bcr and Abr are two physiologically important GAPs for Rac. Here, we report that in the presence of RhoGDIalpha, Bcr is unable to convert Rac-GTP to Rac-GDP because RhoGDI forms a direct protein complex with Bcr. Interestingly, RhoGDIalpha binds to the GAP domain in Bcr and Abr, a domain that also binds to Rac-GTP and catalyzes conversion of the bound GTP to GDP on Rac. The presence of activated Rac diminished the Bcr/RhoGDIalpha interaction. Moreover, a Bcr mutant that lacks the ability to promote hydrolysis of Rac-GTP bound to its GAP domain did not bind to RhoGDIalpha in cell lysates, indicating that binding of RhoGDIalpha and Rac-GTP to the Bcr GAP domain is mutually exclusive. Our results provide the first identification of a protein that regulates BcrGAP activity.
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Affiliation(s)
- Soo-Mi Kweon
- Section of Molecular Carcinogenesis, Division of Hematology/Oncology, The Saban Research Institute, Childrens Hospital Los Angeles, Los Angeles, California 90027
| | - Young Jin Cho
- Section of Molecular Carcinogenesis, Division of Hematology/Oncology, The Saban Research Institute, Childrens Hospital Los Angeles, Los Angeles, California 90027
| | - Parviz Minoo
- Department of Pediatrics, University of Southern California, Los Angeles, California 90033
| | - John Groffen
- Section of Molecular Carcinogenesis, Division of Hematology/Oncology, The Saban Research Institute, Childrens Hospital Los Angeles, Los Angeles, California 90027; Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033
| | - Nora Heisterkamp
- Section of Molecular Carcinogenesis, Division of Hematology/Oncology, The Saban Research Institute, Childrens Hospital Los Angeles, Los Angeles, California 90027; Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033.
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10
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Protein Prenylation: An (Almost) Comprehensive Overview on Discovery History, Enzymology, and Significance in Physiology and Disease. MONATSHEFTE FUR CHEMIE 2006. [DOI: 10.1007/s00706-006-0534-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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11
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Forget MA, Desrosiers RR, Gingras D, Béliveau R. Phosphorylation states of Cdc42 and RhoA regulate their interactions with Rho GDP dissociation inhibitor and their extraction from biological membranes. Biochem J 2002; 361:243-54. [PMID: 11772396 PMCID: PMC1222304 DOI: 10.1042/0264-6021:3610243] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The Rho GDP dissociation inhibitor (RhoGDI) regulates the activation-inactivation cycle of Rho small GTPases, such as Cdc42 and RhoA, by extracting them from the membrane. To study the roles of Mg(2+), phosphatidylinositol 4,5-bisphosphate (PIP(2)), ionic strength and phosphorylation on the interactions of RhoGDI with Cdc42 and RhoA, we developed a new, efficient and reliable method to produce prenylated Rho proteins using the yeast Saccharomyces cerevisiae. It has been previously reported that protein kinase A (PKA)-treatment of isolated membranes increased RhoA extraction from membranes by RhoGDI [Lang, Gesbert, Delespine-Carmagnat, Stancou, Pouchelet and Bertoglio (1996) EMBO J. 16, 510-519]. In the present study, we used an in vitro affinity chromatography system to show that phosphorylation of RhoA and Cdc42 significantly increased their interaction with RhoGDI under physiological conditions of ionic strength. This increase was independent of the nucleotide (GDP or guanosine 5'-[gamma-thio]triphosphate) loaded on to the Rho proteins, as well as of Mg(2+) and PIP(2). Moreover, dephosphorylation of rat brain membranes by alkaline phosphatase significantly decreased the extraction of RhoA and Cdc42 by RhoGDI. Subsequent re-phosphorylation by PKA restored the extraction levels, indicating the reversibility of this process. These results clearly demonstrate that the phosphorylation states of Cdc42 and RhoA regulate their interactions with RhoGDI and, consequently, their extraction from rat brain membranes. We therefore suggest that phosphorylation is a mechanism of regulation of Cdc42 and RhoA activity that is independent of GDP-GTP cycling.
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Affiliation(s)
- Marie-Annick Forget
- Laboratoire de médecine moléculaire, Hôpital Sainte-Justine-Université du Québec à Montréal, P.O. Box 8888, Centre-ville station, Montréal, Québec, Canada H3C 3P8
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12
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Affiliation(s)
- P W Read
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville 22908-0736, USA
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13
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Abstract
Post-translational modification of proteins with isoprenoids was first recognized as a general phenomenon in 1984. In recent years, our understanding, including mechanistic studies, of the enzymatic reactions associated with these modifications and their physiological functions has increased dramatically. Of particular functional interest is the role of prenylation in facilitating protein-protein interactions and membrane-associated protein trafficking. The loss of proper localization of Ras proteins when their farnesylation is inhibited has also permitted a new target for anti-malignancy pharmaceuticals. Recent advances in the enzymology and function of protein prenylation are reviewed in this article.
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Affiliation(s)
- M Sinensky
- Department of Biochemistry and Molecular Biology, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614-0581, USA.
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