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Steiert B, Icardi CM, Faris R, McCaslin PN, Smith P, Klingelhutz AJ, Yau PM, Weber MM. The Chlamydia trachomatis type III-secreted effector protein CteG induces centrosome amplification through interactions with centrin-2. Proc Natl Acad Sci U S A 2023; 120:e2303487120. [PMID: 37155906 PMCID: PMC10193975 DOI: 10.1073/pnas.2303487120] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 04/11/2023] [Indexed: 05/10/2023] Open
Abstract
The centrosome is the main microtubule organizing center of the cell and is crucial for mitotic spindle assembly, chromosome segregation, and cell division. Centrosome duplication is tightly controlled, yet several pathogens, most notably oncogenic viruses, perturb this process leading to increased centrosome numbers. Infection by the obligate intracellular bacterium Chlamydia trachomatis (C.t.) correlates with blocked cytokinesis, supernumerary centrosomes, and multipolar spindles; however, the mechanisms behind how C.t. induces these cellular abnormalities remain largely unknown. Here we show that the secreted effector protein, CteG, binds to centrin-2 (CETN2), a key structural component of centrosomes and regulator of centriole duplication. Our data indicate that both CteG and CETN2 are necessary for infection-induced centrosome amplification, in a manner that requires the C-terminus of CteG. Strikingly, CteG is important for in vivo infection and growth in primary cervical cells but is dispensable for growth in immortalized cells, highlighting the importance of this effector protein to chlamydial infection. These findings begin to provide mechanistic insight into how C.t. induces cellular abnormalities during infection, but also indicate that obligate intracellular bacteria may contribute to cellular transformation events. Centrosome amplification mediated by CteG-CETN2 interactions may explain why chlamydial infection leads to an increased risk of cervical or ovarian cancer.
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Affiliation(s)
- Brianna Steiert
- Department of Microbiology and Immunology, University of Iowa Carver College of Medicine, Iowa City, IA52242
| | - Carolina M. Icardi
- Department of Microbiology and Immunology, University of Iowa Carver College of Medicine, Iowa City, IA52242
| | - Robert Faris
- Department of Microbiology and Immunology, University of Iowa Carver College of Medicine, Iowa City, IA52242
| | - Paige N. McCaslin
- Department of Microbiology and Immunology, University of Iowa Carver College of Medicine, Iowa City, IA52242
| | - Parker Smith
- Department of Microbiology and Immunology, University of Iowa Carver College of Medicine, Iowa City, IA52242
| | - Aloysius J. Klingelhutz
- Department of Microbiology and Immunology, University of Iowa Carver College of Medicine, Iowa City, IA52242
| | - Peter M. Yau
- Carver Biotechnology Center–Protein Sciences Facility, University of Illinois at Urbana–Champaign, Urbana, IL61801
| | - Mary M. Weber
- Department of Microbiology and Immunology, University of Iowa Carver College of Medicine, Iowa City, IA52242
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2
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Laporte MH, Bouhlel IB, Bertiaux E, Morrison CG, Giroud A, Borgers S, Azimzadeh J, Bornens M, Guichard P, Paoletti A, Hamel V. Human SFI1 and Centrin form a complex critical for centriole architecture and ciliogenesis. EMBO J 2022; 41:e112107. [PMID: 36125182 DOI: 10.15252/embj.2022112107] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 08/23/2022] [Accepted: 09/02/2022] [Indexed: 11/09/2022] Open
Abstract
Over the course of evolution, the centrosome function has been conserved in most eukaryotes, but its core architecture has evolved differently in some clades, with the presence of centrioles in humans and a spindle pole body (SPB) in yeast. Similarly, the composition of these two core elements has diverged, with the exception of Centrin and SFI1, which form a complex in yeast to initiate SPB duplication. However, it remains unclear whether this complex exists at centrioles and whether its function has been conserved. Here, using expansion microscopy, we demonstrate that human SFI1 is a centriolar protein that associates with a pool of Centrin at the distal end of the centriole. We also find that both proteins are recruited early during procentriole assembly and that depletion of SFI1 results in the loss of the distal pool of Centrin, without altering centriole duplication. Instead, we show that SFI1/Centrin complex is essential for centriolar architecture, CEP164 distribution, and CP110 removal during ciliogenesis. Together, our work reveals a conserved SFI1/Centrin module displaying divergent functions between mammals and yeast.
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Affiliation(s)
- Marine H Laporte
- Department of Molecular and Cellular Biology, University of Geneva, Geneva, Switzerland
| | - Imène B Bouhlel
- Institut Curie, UMR 144, CNRS, PSL University, Paris, France
| | - Eloïse Bertiaux
- Department of Molecular and Cellular Biology, University of Geneva, Geneva, Switzerland
| | - Ciaran G Morrison
- Department of Molecular and Cellular Biology, University of Geneva, Geneva, Switzerland.,Centre for Chromosome Biology, School of Biological and Chemical Sciences, National University of Ireland Galway, Galway, Ireland
| | - Alexia Giroud
- Department of Molecular and Cellular Biology, University of Geneva, Geneva, Switzerland
| | - Susanne Borgers
- Department of Molecular and Cellular Biology, University of Geneva, Geneva, Switzerland
| | | | - Michel Bornens
- Institut Curie, UMR 144, CNRS, PSL University, Paris, France
| | - Paul Guichard
- Department of Molecular and Cellular Biology, University of Geneva, Geneva, Switzerland
| | - Anne Paoletti
- Institut Curie, UMR 144, CNRS, PSL University, Paris, France
| | - Virginie Hamel
- Department of Molecular and Cellular Biology, University of Geneva, Geneva, Switzerland
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3
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Conformational Plasticity of Centrin 1 from Toxoplasma gondii in Binding to the Centrosomal Protein SFI1. Biomolecules 2022; 12:biom12081115. [PMID: 36009009 PMCID: PMC9406199 DOI: 10.3390/biom12081115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 08/09/2022] [Accepted: 08/10/2022] [Indexed: 12/01/2022] Open
Abstract
Centrins are calcium (Ca2+)-binding proteins that are involved in many cellular functions including centrosome regulation. A known cellular target of centrins is SFI1, a large centrosomal protein containing multiple repeats that represent centrin-binding motifs. Recently, a protein homologous to yeast and mammalian SFI1, denominated TgSFI1, which shares SFI1-repeat organization, was shown to colocalize at centrosomes with centrin 1 from Toxoplasma gondii (TgCEN1). However, the molecular details of the interaction between TgCEN1 and TgSFI1 remain largely unknown. Herein, combining different biophysical methods, including isothermal titration calorimetry, nuclear magnetic resonance, circular dichroism, and fluorescence spectroscopy, we determined the binding properties of TgCEN1 and its individual N- and C-terminal domains to synthetic peptides derived from distinct repeats of TgSFI1. Overall, our data indicate that the repeats in TgSFI1 constitute binding sites for TgCEN1, but the binding modes of TgCEN1 to the repeats differ appreciably in terms of binding affinity, Ca2+ sensitivity, and lobe-specific interaction. These results suggest that TgCEN1 displays remarkable conformational plasticity, allowing for the distinct repeats in TgSFI1 to possess precise modes of TgCEN1 binding and regulation during Ca2+ sensing, which appears to be crucial for the dynamic association of TgCEN1 with TgSFI1 in the centrosome architecture.
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Structural Basis for the Functional Diversity of Centrins: A Focus on Calcium Sensing Properties and Target Recognition. Int J Mol Sci 2021; 22:ijms222212173. [PMID: 34830049 PMCID: PMC8622359 DOI: 10.3390/ijms222212173] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 11/04/2021] [Accepted: 11/06/2021] [Indexed: 11/23/2022] Open
Abstract
Centrins are a family of small, EF hand-containing proteins that are found in all eukaryotes and are often complexed with centrosome-related structures. Since their discovery, centrins have attracted increasing interest due to their multiple, diverse cellular functions. Centrins are similar to calmodulin (CaM) in size, structure and domain organization, although in contrast to CaM, the majority of centrins possess at least one calcium (Ca2+) binding site that is non-functional, thus displaying large variance in Ca2+ sensing abilities that could support their functional versatility. In this review, we summarize current knowledge on centrins from both biophysical and structural perspectives with an emphasis on centrin-target interactions. In-depth analysis of the Ca2+ sensing properties of centrins and structures of centrins complexed with target proteins can provide useful insight into the mechanisms of the different functions of centrins and how these proteins contribute to the complexity of the Ca2+ signaling cascade. Moreover, it can help to better understand the functional redundancy of centrin isoforms and centrin-binding proteins.
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The interplay of self-assembly and target binding in centrin 1 from Toxoplasma gondii. Biochem J 2021; 478:2571-2587. [PMID: 34114596 PMCID: PMC8286830 DOI: 10.1042/bcj20210295] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 06/09/2021] [Accepted: 06/11/2021] [Indexed: 11/17/2022]
Abstract
Centrins are conserved calcium (Ca2+)-binding proteins typically associated with centrosomes that have been implicated in several biological processes. In Toxoplasma gondii, a parasite that causes toxoplasmosis, three centrin isoforms have been recognized. We have recently characterized the metal binding and structural features of isoform 1 (TgCEN1), demonstrating that it possesses properties consistent with a role as a Ca2+ sensor and displays a Ca2+-dependent tendency to self-assemble. Herein, we expanded our studies, focusing on the self-association and target binding properties of TgCEN1 by combining biophysical techniques including dynamic light scattering, isothermal titration calorimetry, nuclear magnetic resonance, circular dichroism, and fluorescence spectroscopy. We found that the self-assembly process of TgCEN1 depends on different physicochemical factors, including Ca2+ concentration, temperature, and protein concentration, and is mediated by both electrostatic and hydrophobic interactions. The process is completely abolished upon removal of the first 21-residues of the protein and is significantly reduced in the presence of a binding target peptide derived from the human XPC protein (P17-XPC). Titration of P17-XPC to the intact protein and isolated domains showed that TgCEN1 possesses two binding sites with distinct affinities and Ca2+ sensitivity; a high-affinity site in the C-lobe which may be constitutively bound to the peptide and a low-affinity site in the N-lobe which is active only upon Ca2+ stimulus. Overall, our results suggest a specific mechanism of TgCEN1 for Ca2+-modulated target binding and support a N-to-C self-assembly mode, in which the first 21-residues of one molecule likely interact with the C-lobe of the other.
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6
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SAC3B is a target of CML19, the centrin 2 of Arabidopsis thaliana. Biochem J 2020; 477:173-189. [PMID: 31860002 DOI: 10.1042/bcj20190674] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 12/17/2019] [Accepted: 12/18/2019] [Indexed: 01/15/2023]
Abstract
Arabidopsis centrin 2, also known as calmodulin-like protein 19 (CML19), is a member of the EF-hand superfamily of calcium (Ca2+)-binding proteins. In addition to the notion that CML19 interacts with the nucleotide excision repair protein RAD4, CML19 was suggested to be a component of the transcription export complex 2 (TREX-2) by interacting with SAC3B. However, the molecular determinants of this interaction have remained largely unknown. Herein, we identified a CML19-binding site within the C-terminus of SAC3B and characterized the binding properties of the corresponding 26-residue peptide (SAC3Bp), which exhibits the hydrophobic triad centrin-binding motif in a reversed orientation (I8W4W1). Using a combination of spectroscopic and calorimetric experiments, we shed light on the SAC3Bp-CML19 complex structure in solution. We demonstrated that the peptide interacts not only with Ca2+-saturated CML19, but also with apo-CML19 to form a protein-peptide complex with a 1 : 1 stoichiometry. Both interactions involve hydrophobic and electrostatic contributions and include the burial of Trp residues of SAC3Bp. However, the peptide likely assumes different conformations upon binding to apo-CML19 or Ca2+-CML19. Importantly, the peptide dramatically increases the affinity for Ca2+ of CML19, especially of the C-lobe, suggesting that in vivo the protein would be Ca2+-saturated and bound to SAC3B even at resting Ca2+-levels. Our results, providing direct evidence that Arabidopsis SAC3B is a CML19 target and proposing that CML19 can bind to SAC3B through its C-lobe independent of a Ca2+ stimulus, support a functional role for these proteins in TREX-2 complex and mRNA export.
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Karlsson L, Barbaro M, Ewing E, Gomez-Cabrero D, Lajic S. Genome-wide investigation of DNA methylation in congenital adrenal hyperplasia. J Steroid Biochem Mol Biol 2020; 201:105699. [PMID: 32428554 DOI: 10.1016/j.jsbmb.2020.105699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 05/09/2020] [Accepted: 05/09/2020] [Indexed: 11/23/2022]
Abstract
Patients with congenital adrenal hyperplasia (CAH) are at risk of long-term cognitive and metabolic sequelae with some of the effects being attributed to the chronic glucocorticoid treatment that they receive. Our pilot study investigates genome-wide DNA methylation in patients with CAH to determine whether there is preliminary evidence for epigenomic reprogramming as well as any relationship to patient outcome. Here, we analysed CD4 + T cell DNA from 28 patients with CAH (mean age = 18.5 ± 6.5 years [y]) and 37 population controls (mean age = 17.0 ± 6.1 y) with the Infinium-HumanMethylation450 BeadChip array to measure genome-wide locus-specific DNA methylation levels. Effects of CAH, phenotype and CYP21A2 genotype on methylation were investigated as well as the association between differentially methylated CpGs and glucose homeostasis, blood lipid profile, and cognitive functions. In addition, we report data on a small cohort of 11 patients (mean age = 19.1, ±6.0 y) with CAH who were treated prenatally with dexamethasone (DEX) in addition to postnatal glucocorticoid treatment. We identified two CpGs to be associated with patient phenotype: cg18486102 (located in the FAIM2 gene; rho = 0.58, adjusted p = 0.027) and cg02404636 (located in the SFI1 gene; rho = 0.58, adjusted p = 0.038). cg02404636 was also associated with genotype (rho = 0.59, adjusted p = 0.024). Higher levels of serum C-peptide was also observed in patients with CAH (p = 0.044). Additionally, levels of C-peptide and HbA1c were positively correlated with patient phenotype (p = 0.044 and p = 0.034) and genotype (p = 0.044 and p = 0.033), respectively. No significant association was found between FAIM2 methylation and cognitive or metabolic outcome. However, SFI1 TSS methylation was associated with fasting plasma HDL cholesterol levels (p = 0.035). In conclusion, in this pilot study, higher methylation levels in CpG sites covering FAIM2 and SFI1 were associated with disease severity. Hypermethylation in these genes may have implications for long-term cognitive and metabolic outcome in patients with CAH, although the data must be interpreted with caution due to the small sample size. Additional studies in larger cohorts are therefore warranted.
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Affiliation(s)
- Leif Karlsson
- Department of Women's and Children's Health, Karolinska Institutet, Paediatric Endocrinology Unit (QB83), Karolinska University Hospital, SE-171 76 Stockholm, Sweden
| | - Michela Barbaro
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Karolinska University Hospital, SE-171 76 Stockholm, Sweden; Center for Inherited Metabolic Diseases (CMMS L7:05), Karolinska University Hospital, SE-171 76 Stockholm, Sweden
| | - Ewoud Ewing
- Department of Clinical Neuroscience, Centre for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - David Gomez-Cabrero
- Department of Women's and Children's Health, Paediatric Endocrinology Unit (QB83), Karolinska University Hospital, SE-171 76 Stockholm, Sweden
| | - Svetlana Lajic
- Department of Women's and Children's Health, Karolinska Institutet, Paediatric Endocrinology Unit (QB83), Karolinska University Hospital, SE-171 76 Stockholm, Sweden
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8
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Heydeck W, Bayless BA, Stemm-Wolf AJ, O'Toole ET, Fabritius AS, Ozzello C, Nguyen M, Winey M. Tetrahymena Poc5 is a transient basal body component that is important for basal body maturation. J Cell Sci 2020; 133:jcs.240838. [PMID: 32350068 DOI: 10.1242/jcs.240838] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Accepted: 04/06/2020] [Indexed: 01/26/2023] Open
Abstract
Basal bodies (BBs) are microtubule-based organelles that act as a template for and stabilize cilia at the cell surface. Centrins ubiquitously associate with BBs and function in BB assembly, maturation and stability. Human POC5 (hPOC5) is a highly conserved centrin-binding protein that binds centrins through Sfi1p-like repeats and is required for building full-length, mature centrioles. Here, we use the BB-rich cytoskeleton of Tetrahymena thermophila to characterize Poc5 BB functions. Tetrahymena Poc5 (TtPoc5) uniquely incorporates into assembling BBs and is then removed from mature BBs prior to ciliogenesis. Complete genomic knockout of TtPOC5 leads to a significantly increased production of BBs, yet a markedly reduced ciliary density, both of which are rescued by reintroduction of TtPoc5. A second Tetrahymena POC5-like gene, SFR1, is similarly implicated in modulating BB production. When TtPOC5 and SFR1 are co-deleted, cell viability is compromised and BB overproduction is exacerbated. Overproduced BBs display defective transition zone formation and a diminished capacity for ciliogenesis. This study uncovers a requirement for Poc5 in building mature BBs, providing a possible functional link between hPOC5 mutations and impaired cilia.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Westley Heydeck
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO 80309, USA
| | - Brian A Bayless
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA
| | - Alexander J Stemm-Wolf
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Eileen T O'Toole
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO 80309, USA
| | - Amy S Fabritius
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA
| | - Courtney Ozzello
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO 80309, USA
| | - Marina Nguyen
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA
| | - Mark Winey
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA
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Khouj EM, Prosser SL, Tada H, Chong WM, Liao JC, Sugasawa K, Morrison CG. Differential requirements for the EF-hand domains of human centrin 2 in primary ciliogenesis and nucleotide excision repair. J Cell Sci 2019; 132:jcs.228486. [PMID: 31492759 DOI: 10.1242/jcs.228486] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 08/29/2019] [Indexed: 12/16/2022] Open
Abstract
Centrin 2 is a small conserved calcium-binding protein that localizes to the centriolar distal lumen in human cells. It is required for efficient primary ciliogenesis and nucleotide excision repair (NER). Centrin 2 forms part of the xeroderma pigmentosum group C protein complex. To explore how centrin 2 contributes to these distinct processes, we mutated the four calcium-binding EF-hand domains of human centrin 2. Centrin 2 in which all four EF-hands had been mutated to ablate calcium binding (4DA mutant) was capable of supporting in vitro NER and was as effective as the wild-type protein in rescuing the UV sensitivity of centrin 2-null cells. However, we found that mutation of any of the EF-hand domains impaired primary ciliogenesis in human TERT-RPE1 cells to the same extent as deletion of centrin 2. Phenotypic analysis of the 4DA mutant revealed defects in centrosome localization, centriole satellite assembly, ciliary assembly and function and in interactions with POC5 and SFI1. These observations indicate that centrin 2 requires calcium-binding capacity for its primary ciliogenesis functions, but not for NER, and suggest that these functions require centrin 2 to be capable of forming complexes with partner proteins.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Ebtissal M Khouj
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Galway H91 W2TY, Ireland
| | - Suzanna L Prosser
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Galway H91 W2TY, Ireland.,Lunenfeld-Tanenbaum Research Institute, Sinai Health System, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada
| | - Haruto Tada
- Biosignal Research Center, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan.,Graduate School of Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Weng Man Chong
- IAMS Academia Sinica, No 1 Roosevelt Rd Sec 4, 10617 Taipei City, Taiwan
| | - Jung-Chi Liao
- IAMS Academia Sinica, No 1 Roosevelt Rd Sec 4, 10617 Taipei City, Taiwan
| | - Kaoru Sugasawa
- Biosignal Research Center, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan.,Graduate School of Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Ciaran G Morrison
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Galway H91 W2TY, Ireland
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Kodani A, Moyer T, Chen A, Holland A, Walsh CA, Reiter JF. SFI1 promotes centriole duplication by recruiting USP9X to stabilize the microcephaly protein STIL. J Cell Biol 2019; 218:2185-2197. [PMID: 31197030 PMCID: PMC6605807 DOI: 10.1083/jcb.201803041] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 12/18/2018] [Accepted: 05/10/2019] [Indexed: 01/08/2023] Open
Abstract
In mammals, centrioles participate in brain development, and human mutations affecting centriole duplication cause microcephaly. Here, we identify a role for the mammalian homologue of yeast SFI1, involved in the duplication of the yeast spindle pole body, as a critical regulator of centriole duplication in mammalian cells. Mammalian SFI1 interacts with USP9X, a deubiquitylase associated with human syndromic mental retardation. SFI1 localizes USP9X to the centrosome during S phase to deubiquitylate STIL, a critical regulator of centriole duplication. USP9X-mediated deubiquitylation protects STIL from degradation. Consistent with a role for USP9X in stabilizing STIL, cells from patients with USP9X loss-of-function mutations have reduced STIL levels. Together, these results demonstrate that SFI1 is a centrosomal protein that localizes USP9X to the centrosome to stabilize STIL and promote centriole duplication. We propose that the USP9X protection of STIL to facilitate centriole duplication underlies roles of both proteins in human neurodevelopment.
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Affiliation(s)
- Andrew Kodani
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA
- Division of Genetics and Genomics and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA
| | - Tyler Moyer
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Allen Chen
- Division of Genetics and Genomics and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA
| | - Andrew Holland
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Christopher A Walsh
- Division of Genetics and Genomics and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA
| | - Jeremy F Reiter
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA
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11
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Baehr W, Hanke-Gogokhia C, Sharif A, Reed M, Dahl T, Frederick JM, Ying G. Insights into photoreceptor ciliogenesis revealed by animal models. Prog Retin Eye Res 2018; 71:26-56. [PMID: 30590118 DOI: 10.1016/j.preteyeres.2018.12.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 12/10/2018] [Accepted: 12/18/2018] [Indexed: 12/11/2022]
Abstract
Photoreceptors are polarized neurons, with very specific subcellular compartmentalization and unique requirements for protein expression and trafficking. Each photoreceptor contains an outer segment, the site of photon capture that initiates vision, an inner segment that houses the biosynthetic machinery and a synaptic terminal for signal transmission to downstream neurons. Outer segments and inner segments are connected by a connecting cilium (CC), the equivalent of a transition zone (TZ) of primary cilia. The connecting cilium is part of the basal body/axoneme backbone that stabilizes the outer segment. This report will update the reader on late developments in photoreceptor ciliogenesis and transition zone formation, specifically in mouse photoreceptors, focusing on early events in photoreceptor ciliogenesis. The connecting cilium, an elongated and narrow structure through which all outer segment proteins and membrane components must traffic, functions as a gate that controls access to the outer segment. Here we will review genes and their protein products essential for basal body maturation and for CC/TZ genesis, sorted by phenotype. Emphasis is given to naturally occurring mouse mutants and gene knockouts that interfere with CC/TZ formation and ciliogenesis.
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Affiliation(s)
- Wolfgang Baehr
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA.
| | - Christin Hanke-Gogokhia
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
| | - Ali Sharif
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
| | - Michelle Reed
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
| | - Tiffanie Dahl
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
| | - Jeanne M Frederick
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
| | - Guoxin Ying
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
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12
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Chen L, Bian S, Li H, Madura K. A role for Saccharomyces cerevisiae Centrin (Cdc31) in mitochondrial function and biogenesis. Mol Microbiol 2018; 110:831-846. [PMID: 30251372 DOI: 10.1111/mmi.14128] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 08/24/2018] [Accepted: 09/09/2018] [Indexed: 11/28/2022]
Abstract
Centrins belong to a family of proteins containing calcium-binding EF-hand motifs that perform well-established roles in centrosome and spindle pole body (SPB) duplication. Yeast encodes a single Centrin protein (Cdc31) that binds components in the SPB. However, further studies revealed a role for Centrins in mRNA export, and interactions with contractile filaments and photoreceptors. In addition, human Centrin-2 can bind the DNA-lesion recognition factor XPC, and improve the efficiency of nucleotide excision repair. Similarly, we reported that yeast Cdc31 binds Rad4, a functional counterpart of the XPC DNA repair protein. We also found that Cdc31 is involved in the ubiquitin/proteasome system, and mutations interfere with intracellular protein turnover. In this report, we describe new findings that indicate a role for Cdc31 in the energy metabolism pathway. Cdc31 and cdc31 mutant proteins showed distinct interactions with proteins in energy metabolism, and mutants showed sensitivity to oxidative stress and poor growth on non-fermentable carbon. Significant alteration in mitochondrial morphology was also detected. Although it is unclear how Cdc31 contributes to so many unrelated mechanisms, we propose that by controlling SPB duplication Centrin proteins might link the cellular responses to DNA damage, oxidative load and proteotoxic stresses to growth control.
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Affiliation(s)
- Li Chen
- Department of Pharmacology, Robert Wood Johnson Medical School, Rutgers University, 683 Hoes Lane, SPH-383, Piscataway, NJ, 08854, USA
| | - Shengjie Bian
- Center for Advanced Proteomics Research, New Jersey Medical School, Rutgers University, 185 S. Orange Ave., Newark, NJ, 07103, USA
| | - Hong Li
- Center for Advanced Proteomics Research, New Jersey Medical School, Rutgers University, 185 S. Orange Ave., Newark, NJ, 07103, USA
| | - Kiran Madura
- Department of Pharmacology, Robert Wood Johnson Medical School, Rutgers University, 683 Hoes Lane, SPH-383, Piscataway, NJ, 08854, USA
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Uli N, Michelen-Gomez E, Ramos EI, Druley TE. Age-specific changes in genome-wide methylation enrich for Foxa2 and estrogen receptor alpha binding sites. PLoS One 2018; 13:e0203147. [PMID: 30256791 PMCID: PMC6157835 DOI: 10.1371/journal.pone.0203147] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 08/15/2018] [Indexed: 12/26/2022] Open
Abstract
The role of DNA methylation patterns in complex phenotypes remains unclear. To explore this question, we adapted our methods for rare variant analysis to characterize genome-wide murine DNA hybridization array to investigate methylation at CpG islands, shores, and regulatory elements. We have applied this platform to compare age and tissue- specific methylation differences in the brain and spleen of young and aged mice. As expected from prior studies, there are clear global differences in organ-specific, but not age-specific, methylation due mostly to changes at repetitive elements. Surprisingly, out of 200,000 loci there were only 946 differentially methylated cytosines (DMCs) between young and old samples (529 hypermethylated, 417 hypomethylated in aged mice) compared to thousands of tissue-specific DMCs. Hypermethylated loci were clustered around the promoter region of Sfi1, exon 2 of Slc11a2, Drg1, Esr1 and Foxa2 transcription factor binding sites. In particular, there were 75 hypermethylated Foxa2 binding sites across a 2.7 Mb region of chromosome 11. Hypomethylated loci were clustered around Mid1, Isoc2b and genome-wide loci with binding sites for Foxa2 and Esr1, which are known to play important roles in development and aging. These data suggest discreet tissue-independent methylation changes associated with aging processes such as cell division (Sfi1, Mid1), energy production (Drg1, Isoc2b) and cell death (Foxa2, Esr1).
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Affiliation(s)
- Nishanth Uli
- Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Eduardo Michelen-Gomez
- Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Enrique I. Ramos
- Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Todd E. Druley
- Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- * E-mail:
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14
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Ito D, Bettencourt-Dias M. Centrosome Remodelling in Evolution. Cells 2018; 7:E71. [PMID: 29986477 PMCID: PMC6070874 DOI: 10.3390/cells7070071] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Revised: 06/27/2018] [Accepted: 07/04/2018] [Indexed: 11/16/2022] Open
Abstract
The centrosome is the major microtubule organizing centre (MTOC) in animal cells. The canonical centrosome is composed of two centrioles surrounded by a pericentriolar matrix (PCM). In contrast, yeasts and amoebozoa have lost centrioles and possess acentriolar centrosomes—called the spindle pole body (SPB) and the nucleus-associated body (NAB), respectively. Despite the difference in their structures, centriolar centrosomes and SPBs not only share components but also common biogenesis regulators. In this review, we focus on the SPB and speculate how its structures evolved from the ancestral centrosome. Phylogenetic distribution of molecular components suggests that yeasts gained specific SPB components upon loss of centrioles but maintained PCM components associated with the structure. It is possible that the PCM structure remained even after centrosome remodelling due to its indispensable function to nucleate microtubules. We propose that the yeast SPB has been formed by a step-wise process; (1) an SPB-like precursor structure appeared on the ancestral centriolar centrosome; (2) it interacted with the PCM and the nuclear envelope; and (3) it replaced the roles of centrioles. Acentriolar centrosomes should continue to be a great model to understand how centrosomes evolved and how centrosome biogenesis is regulated.
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Affiliation(s)
- Daisuke Ito
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, 2780-156 Oeiras, Portugal.
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15
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Shi E, Zhang W, Zhao Y, Yang B. Binding of Euplotes octocarinatus centrin to peptide from xeroderma pigmentosum group C protein (XPC). RSC Adv 2017. [DOI: 10.1039/c7ra03079g] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Trp is buried in the hydrophobic cavity, the peptide folds into an α-helix, and the interaction is enthalpically driven from ITC.
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Affiliation(s)
- Enxian Shi
- Institute of Molecular Science
- Key Laboratory of Chemical Biology of Molecular Engineering of Education Ministry
- Shanxi University
- Taiyuan 030006
- PR China
| | - Wenlong Zhang
- Institute of Molecular Science
- Key Laboratory of Chemical Biology of Molecular Engineering of Education Ministry
- Shanxi University
- Taiyuan 030006
- PR China
| | - Yaqin Zhao
- Institute of Molecular Science
- Key Laboratory of Chemical Biology of Molecular Engineering of Education Ministry
- Shanxi University
- Taiyuan 030006
- PR China
| | - Binsheng Yang
- Institute of Molecular Science
- Key Laboratory of Chemical Biology of Molecular Engineering of Education Ministry
- Shanxi University
- Taiyuan 030006
- PR China
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16
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Abstract
The yeast spindle pole body (SPB) is the functional equivalent of the mammalian centrosome. Centrosomes and SPBs duplicate exactly once per cell cycle by mechanisms that use the mother structure as a platform for the assembly of the daughter. The conserved Sfi1 and centrin proteins are essential components of the SPB duplication process. Sfi1 is an elongated molecule that has, in its center, 20 to 23 binding sites for the Ca(2+)-binding protein centrin. In the yeastSaccharomyces cerevisiae, all Sfi1 N termini are in contact with the mother SPB whereas the free C termini are distal to it. During S phase and early mitosis, cyclin-dependent kinase 1 (Cdk1) phosphorylation of mainly serine residues in the Sfi1 C termini blocks the initiation of SPB duplication ("off" state). Upon anaphase onset, the phosphatase Cdc14 dephosphorylates Sfi1 ("on" state) to promote antiparallel and shifted incorporation of cytoplasmic Sfi1 molecules into the half-bridge layer, which thereby elongates into the bridge. The Sfi1 C termini of the two Sfi1 layers localize in the bridge center, whereas the N termini of the newly assembled Sfi1 molecules are distal to the mother SPB. These free Sfi1 N termini then assemble the new SPB in G1phase. Recruitment of Sfi1 molecules into the anaphase SPB and bridge formation were also observed inSchizosaccharomyces pombe, suggesting that the Sfi1 bridge cycle is conserved between the two organisms. Thus, restricting SPB duplication to one event per cell cycle requires only an oscillation between Cdk1 kinase and Cdc14 phosphatase activities. This clockwork regulates the "on"/"off" state of the Sfi1-centrin receiver.
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17
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Grecu D, Irudayaraj VPR, Martinez-Sanz J, Mallet JM, Assairi L. A chirality change in XPC- and Sfi1-derived peptides affects their affinity for centrin. Peptides 2016; 78:77-86. [PMID: 26923803 DOI: 10.1016/j.peptides.2016.02.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 02/18/2016] [Accepted: 02/19/2016] [Indexed: 12/30/2022]
Abstract
The Ca(2+)-binding protein centrin binds to a hydrophobic motif (W(1)xxL(4)xxxL(8)) included in the sequence of several cellular targets: XPC (xeroderma pigmentosum group C protein), Sfi1 (suppressor of fermentation-induced loss of stress resistance protein1), and Sac3 [the central component of the transcription and mRNA export (TREX-2) complex]. However, centrin binding occurs in a reversed orientation (L(8)xxxL(4)xxW(1)) for Sfi1 and Sac3 compared with XPC. Because D-peptides have been investigated for future therapeutic use, we analyzed their centrin-binding properties. Their affinity for centrin was measured using isothermal titration calorimetry. The chirality change in the target-derived peptides affected their ability to bind centrin in a specific manner depending on the sequence orientation of the centrin-binding motif. In contrast to L-XPC-P10, D-XPC-P10 bound C-HsCen1 in a Ca(2+)-dependent manner and to a lesser extent. D-XPC-P10 exhibited a reduced affinity for C-HsCen1 (Ka=0.064 × 10(6) M(-1)) by a factor of 2000 compared with L-XPC-P10 (Ka=132 × 10(6) M(-1)). D-peptides have a lower affinity than L-peptides for centrin, and the strength of this affinity depends on the sequence orientation of the target-derived peptides. The residual affinity observed for D-XPC suggests that the use of d-peptides represents a promising strategy for inhibiting centrin binding to its targets.
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Affiliation(s)
- Dora Grecu
- Institut Curie-Centre de Recherche, F-91405 Orsay Cédex, France; Institut National de la Santé et de la Recherche Médicale (INSERM) U759, F-91405 Orsay Cédex, France
| | - Victor Paul Raj Irudayaraj
- Institut Curie-Centre de Recherche, F-91405 Orsay Cédex, France; Institut National de la Santé et de la Recherche Médicale (INSERM) U759, F-91405 Orsay Cédex, France; UMR CNRS 7203, Paris Cédex 05, France; ENS Ecole Normale Supérieure de Paris, Paris Cédex 05, France; Université Paris 6, Paris Cédex 05, France
| | - Juan Martinez-Sanz
- Institut Curie-Centre de Recherche, F-91405 Orsay Cédex, France; Institut National de la Santé et de la Recherche Médicale (INSERM) U759, F-91405 Orsay Cédex, France; UMR9187-U1196, F-91405 Orsay Cédex, France
| | - Jean-Maurice Mallet
- UMR CNRS 7203, Paris Cédex 05, France; ENS Ecole Normale Supérieure de Paris, Paris Cédex 05, France; Université Paris 6, Paris Cédex 05, France
| | - Liliane Assairi
- Institut Curie-Centre de Recherche, F-91405 Orsay Cédex, France; Institut National de la Santé et de la Recherche Médicale (INSERM) U759, F-91405 Orsay Cédex, France.
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18
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Martinez-Sanz J, Assairi L. New insights into the interaction of centrin with Sfi1. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2016; 1864:319-30. [PMID: 26779587 DOI: 10.1016/j.bbapap.2016.01.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 12/03/2015] [Accepted: 01/08/2016] [Indexed: 10/22/2022]
Abstract
Centrin binds to Rad4(XPC) and Sfi1 through the hydrophobic motif W(1)xxL(4)xxxL(8) in the opposite orientation. Rad4 has one motif, but Sfi1 has approximately 20 repeats, each of which interacts with a centrin molecule. To investigate the parameters involved in centrin binding, we purified a ScSfi1 domain containing 6 repeats complexed with either yeast centrin Cdc31 or human centrin 1. The present study was performed using mutagenesis of centrin and of Sfi1 residues involved in centrin binding and the stability of the centrin-centrin complexes was assessed using thermal denaturation and CD. Calcium stabilized these complexes, as indicated by the Tm increases measured by circular dichroism. The complexes, which were composed of Sfi1 variants and yeast centrin, were analysed in the presence of EDTA. The replacement of W with F within the repeat region yielded a functional repeat (Tm 45°C). The replacement of W with A in two adjacent Sfi1 repeats reduced the thermal stability of the Sfi1-centrin complexes (40°C). We analysed three HsCen1 variants that were homologous to the yeast mutants and induced cell cycle arrest during the G2/M transition. The HsCen1 variants E105K and F113L reduced the thermal stability (50°C, 50°C) of the ScSfi1-HsCen1 complexes; in contrast, the A109T variant exhibited no change in thermal stability relative to the wild-type (60°C). Conversely to ScCdc31, there were no apparent centrin-centrin interactions with wild-type HsCen1, but they did occur for the S170D mutation that mimics PKA phosphorylation at the S170 residue.
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Affiliation(s)
- Juan Martinez-Sanz
- Institut Curie-Centre de Recherche, F-91405 Orsay Cédex, France; Institut National de la Santé et de la Recherche Médicale (INSERM) U759, F-91405 Orsay Cédex, France
| | - Liliane Assairi
- Institut Curie-Centre de Recherche, F-91405 Orsay Cédex, France; Institut National de la Santé et de la Recherche Médicale (INSERM) U759, F-91405 Orsay Cédex, France.
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19
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Seybold C, Elserafy M, Rüthnick D, Ozboyaci M, Neuner A, Flottmann B, Heilemann M, Wade RC, Schiebel E. Kar1 binding to Sfi1 C-terminal regions anchors the SPB bridge to the nuclear envelope. J Cell Biol 2015; 209:843-61. [PMID: 26076691 PMCID: PMC4477856 DOI: 10.1083/jcb.201412050] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 05/20/2015] [Indexed: 11/22/2022] Open
Abstract
The yeast spindle pole body (SPB) is the functional equivalent of the mammalian centrosome. The half bridge is a SPB substructure on the nuclear envelope (NE), playing a key role in SPB duplication. Its cytoplasmic components are the membrane-anchored Kar1, the yeast centrin Cdc31, and the Cdc31-binding protein Sfi1. In G1, the half bridge expands into the bridge through Sfi1 C-terminal (Sfi1-CT) dimerization, the licensing step for SPB duplication. We exploited photo-activated localization microscopy (PALM) to show that Kar1 localizes in the bridge center. Binding assays revealed direct interaction between Kar1 and C-terminal Sfi1 fragments. kar1Δ cells whose viability was maintained by the dominant CDC31-16 showed an arched bridge, indicating Kar1's function in tethering Sfi1 to the NE. Cdc31-16 enhanced Cdc31-Cdc31 interactions between Sfi1-Cdc31 layers, as suggested by binding free energy calculations. In our model, Kar1 binding is restricted to Sfi1-CT and Sfi1 C-terminal centrin-binding repeats, and centrin and Kar1 provide cross-links, while Sfi1-CT stabilizes the bridge and ensures timely SPB separation.
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Affiliation(s)
- Christian Seybold
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
| | - Menattallah Elserafy
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
| | - Diana Rüthnick
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
| | - Musa Ozboyaci
- Heidelberg Institute for Theoretical Studies, 69118 Heidelberg, Germany Heidelberg Graduate School of Mathematical and Computational Methods for the Sciences, Heidelberg University, 69120 Heidelberg, Germany
| | - Annett Neuner
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
| | - Benjamin Flottmann
- Institute for Anatomy and Cell Biology, Functional Neuroanatomy, Heidelberg University, 69120 Heidelberg, Germany Institute for Physical and Theoretical Chemistry, Johann-Wolfgang-Goethe-University Frankfurt, 60438 Frankfurt am Main, Germany
| | - Mike Heilemann
- Institute for Anatomy and Cell Biology, Functional Neuroanatomy, Heidelberg University, 69120 Heidelberg, Germany Institute for Physical and Theoretical Chemistry, Johann-Wolfgang-Goethe-University Frankfurt, 60438 Frankfurt am Main, Germany
| | - Rebecca C Wade
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany Heidelberg Institute for Theoretical Studies, 69118 Heidelberg, Germany Interdisciplinary Center for Scientific Computing, Heidelberg University, 69120 Heidelberg, Germany
| | - Elmar Schiebel
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
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20
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Cunningham CN, Schmidt CA, Schramm NJ, Gaylord MR, Resendes KK. Human TREX2 components PCID2 and centrin 2, but not ENY2, have distinct functions in protein export and co-localize to the centrosome. Exp Cell Res 2013; 320:209-18. [PMID: 24291146 DOI: 10.1016/j.yexcr.2013.11.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 11/15/2013] [Accepted: 11/19/2013] [Indexed: 11/15/2022]
Abstract
TREX-2 is a five protein complex, conserved from yeast to humans, involved in linking mRNA transcription and export. The centrin 2 subunit of TREX-2 is also a component of the centrosome and is additionally involved in a distinctly different process of nuclear protein export. While centrin 2 is a known multifunctional protein, the roles of other human TREX-2 complex proteins other than mRNA export are not known. In this study, we found that human TREX-2 member PCID2 but not ENY2 is involved in some of the same cellular processes as those of centrin 2 apart from the classical TREX-2 function. PCID2 is present at the centrosome in a subset of HeLa cells and this localization is centrin 2 dependent. Furthermore, the presence of PCID2 at the centrosome is prevalent throughout the cell cycle as determined by co-staining with cyclins E, A and B. PCID2 but not ENY2 is also involved in protein export. Surprisingly, siRNA knockdown of PCID2 delayed the rate of nuclear protein export, a mechanism distinct from the effects of centrin 2, which when knocked down inhibits export. Finally we showed that co-depletion of centrin 2 and PCID2 leads to blocking rather than delaying nuclear protein export, indicating the dominance of the centrin 2 phenotype. Together these results represent the first discovery of specific novel functions for PCID2 other than mRNA export and suggest that components of the TREX-2 complex serve alternative shared roles in the regulation of nuclear transport and cell cycle progression.
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Affiliation(s)
- Corey N Cunningham
- Westminster College, Department of Biology, 319 South Market Street, New Wilmington, PA 16172, USA
| | - Casey A Schmidt
- Westminster College, Department of Biology, 319 South Market Street, New Wilmington, PA 16172, USA
| | - Nathaniel J Schramm
- Westminster College, Department of Biology, 319 South Market Street, New Wilmington, PA 16172, USA
| | - Michelle R Gaylord
- Section of Cell and Developmental Biology, Division of Biological Sciences, University of California - San Diego, 9500 Gilman Drive, #0347, La Jolla, CA 92093-0347, USA
| | - Karen K Resendes
- Westminster College, Department of Biology, 319 South Market Street, New Wilmington, PA 16172, USA.
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21
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Nishi R, Sakai W, Tone D, Hanaoka F, Sugasawa K. Structure-function analysis of the EF-hand protein centrin-2 for its intracellular localization and nucleotide excision repair. Nucleic Acids Res 2013; 41:6917-29. [PMID: 23716636 PMCID: PMC3737541 DOI: 10.1093/nar/gkt434] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Centrin-2 is an evolutionarily conserved, calmodulin-related protein, which is involved in multiple cellular functions including centrosome regulation and nucleotide excision repair (NER) of DNA. Particularly to exert the latter function, complex formation with the XPC protein, the pivotal NER damage recognition factor, is crucial. Here, we show that the C-terminal half of centrin-2, containing two calcium-binding EF-hand motifs, is necessary and sufficient for both its localization to the centrosome and interaction with XPC. In XPC-deficient cells, nuclear localization of overexpressed centrin-2 largely depends on co-overexpression of XPC, and mutational analyses of the C-terminal domain suggest that XPC and the major binding partner in the centrosome share a common binding surface on the centrin-2 molecule. On the other hand, the N-terminal domain of centrin-2 also contains two EF-hand motifs but shows only low-binding affinity for calcium ions. Although the N-terminal domain is dispensable for enhancement of the DNA damage recognition activity of XPC, it contributes to augmenting rather weak physical interaction between XPC and XPA, another key factor involved in NER. These results suggest that centrin-2 may have evolved to bridge two protein factors, one with high affinity and the other with low affinity, thereby allowing delicate regulation of various biological processes.
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Affiliation(s)
- Ryotaro Nishi
- Biosignal Research Center, Organization of Advanced Science and Technology, Kobe University, Kobe, Hyogo 657-8501, Japan
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22
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Stemm-Wolf AJ, Meehl JB, Winey M. Sfr13, a member of a large family of asymmetrically localized Sfi1-repeat proteins, is important for basal body separation and stability in Tetrahymena thermophila. J Cell Sci 2013; 126:1659-71. [PMID: 23426847 DOI: 10.1242/jcs.120238] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Directed fluid flow, which is achieved by the coordinated beating of motile cilia, is required for processes as diverse as cellular swimming, developmental patterning and mucus clearance. Cilia are nucleated, anchored and aligned at the plasma membrane by basal bodies, which are cylindrical microtubule-based structures with ninefold radial symmetry. In the unicellular ciliate Tetrahymena thermophila, two centrin family members associated with the basal body are important for both basal body organization and stabilization. We have identified a family of 13 proteins in Tetrahymena that contain centrin-binding repeats related to those identified in the Saccharomyces cerevisiae Sfi1 protein. We have named these proteins Sfr1-Sfr13 (for Sfi1-repeat). Nine of the Sfr proteins localize in unique polarized patterns surrounding the basal body, suggesting non-identical roles in basal body organization and association with basal body accessory structures. Furthermore, the Sfr proteins are found in distinct basal body populations in Tetrahymena cells, indicating that they are responsive to particular developmental programs. A complete genetic deletion of one of the family members, Sfr13, causes unstable basal bodies and defects in daughter basal body separation from the mother, phenotypes also observed with centrin disruption. It is likely that the other Sfr family members are involved in distinct centrin functions, providing specificity to the tasks that centrins perform at basal bodies.
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Affiliation(s)
- Alexander J Stemm-Wolf
- Department of Molecular, Cellular and Developmental Biology, University of Colorado - Boulder, Boulder, CO 80309, USA
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Zhang Y, Foreman O, Wigle DA, Kosari F, Vasmatzis G, Salisbury JL, van Deursen J, Galardy PJ. USP44 regulates centrosome positioning to prevent aneuploidy and suppress tumorigenesis. J Clin Invest 2012. [PMID: 23187126 DOI: 10.1172/jci63084] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Most human tumors have abnormal numbers of chromosomes, a condition known as aneuploidy. The mitotic checkpoint is an important mechanism that prevents aneuploidy by restraining the activity of the anaphase-promoting complex (APC). The deubiquitinase USP44 was identified as a key regulator of APC activation; however, the physiological importance of USP44 and its impact on cancer biology are unknown. To clarify the role of USP44 in mitosis, we engineered a mouse lacking Usp44. We found that USP44 regulated the mitotic checkpoint and prevented chromosome lagging. Mice lacking Usp44 were prone to the development of spontaneous tumors, particularly in the lungs. Additionally, USP44 was frequently downregulated in human lung cancer, and low expression correlated with a poor prognosis. USP44 inhibited chromosome segregation errors independent of its role in the mitotic checkpoint by regulating centrosome separation, positioning, and mitotic spindle geometry. These functions required direct binding to the centriole protein centrin. Our data reveal a new role for the ubiquitin system in mitotic spindle regulation and underscore the importance of USP44 in the pathogenesis of human cancer.
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Affiliation(s)
- Ying Zhang
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA
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24
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Vonderfecht T, Cookson MW, Giddings TH, Clarissa C, Winey M. The two human centrin homologues have similar but distinct functions at Tetrahymena basal bodies. Mol Biol Cell 2012; 23:4766-77. [PMID: 23087207 PMCID: PMC3521684 DOI: 10.1091/mbc.e12-06-0454] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Centrins are a ubiquitous family of small Ca(2+)-binding proteins found at basal bodies that are placed into two groups based on sequence similarity to the human centrins 2 and 3. Analyses of basal body composition in different species suggest that they contain a centrin isoform from each group. We used the ciliate protist Tetrahymena thermophila to gain a better understanding of the functions of the two centrin groups and to determine their potential redundancy. We have previously shown that the Tetrahymena centrin 1 (Cen1), a human centrin 2 homologue, is required for proper basal body function. In this paper, we show that the Tetrahymena centrin 2 (Cen2), a human centrin 3 homologue, has functions similar to Cen1 in basal body orientation, maintenance, and separation. The two are, however, not redundant. A further examination of human centrin 3 homologues shows that they function in a manner distinct from human centrin 2 homologues. Our data suggest that basal bodies require a centrin from both groups in order to function correctly.
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Affiliation(s)
- Tyson Vonderfecht
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado-Boulder, Boulder, CO 80309, USA
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Dantas TJ, Daly OM, Morrison CG. Such small hands: the roles of centrins/caltractins in the centriole and in genome maintenance. Cell Mol Life Sci 2012; 69:2979-97. [PMID: 22460578 PMCID: PMC11114748 DOI: 10.1007/s00018-012-0961-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 02/20/2012] [Accepted: 03/12/2012] [Indexed: 01/11/2023]
Abstract
Centrins are small, highly conserved members of the EF-hand superfamily of calcium-binding proteins that are found throughout eukaryotes. They play a major role in ensuring the duplication and appropriate functioning of the ciliary basal bodies in ciliated cells. They have also been localised to the centrosome, which is the major microtubule organising centre in animal somatic cells. We describe the identification, cloning and characterisation of centrins in multiple eukaryotic species. Although centrins have been implicated in centriole biogenesis, recent results have indicated that centrosome duplication can, in fact, occur in the absence of centrins. We discuss these data and the non-centrosomal functions that are emerging for the centrins. In particular, we discuss the involvement of centrins in nucleotide excision repair, a process that repairs the DNA lesions that are induced primarily by ultraviolet irradiation. We discuss how centrin may be involved in these diverse processes and contribute to nuclear and cytoplasmic events.
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Affiliation(s)
- Tiago J. Dantas
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, University Road, Galway, Ireland
| | - Owen M. Daly
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, University Road, Galway, Ireland
| | - Ciaran G. Morrison
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, University Road, Galway, Ireland
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A Sleeping Beauty mutagenesis screen reveals a tumor suppressor role for Ncoa2/Src-2 in liver cancer. Proc Natl Acad Sci U S A 2012; 109:E1377-86. [PMID: 22556267 DOI: 10.1073/pnas.1115433109] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The Sleeping Beauty (SB) transposon mutagenesis system is a powerful tool that facilitates the discovery of mutations that accelerate tumorigenesis. In this study, we sought to identify mutations that cooperate with MYC, one of the most commonly dysregulated genes in human malignancy. We performed a forward genetic screen with a mouse model of MYC-induced liver cancer using SB-mediated mutagenesis. We sequenced insertions in 63 liver tumor nodules and identified at least 16 genes/loci that contribute to accelerated tumor development. RNAi-mediated knockdown in a liver progenitor cell line further validate three of these genes, Ncoa2/Src-2, Zfx, and Dtnb, as tumor suppressors in liver cancer. Moreover, deletion of Ncoa2/Src-2 in mice predisposes to diethylnitrosamine-induced liver tumorigenesis. These findings reveal genes and pathways that functionally restrain MYC-mediated liver tumorigenesis and therefore may provide targets for cancer therapy.
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27
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Vonderfecht T, Stemm-Wolf AJ, Hendershott M, Giddings TH, Meehl JB, Winey M. The two domains of centrin have distinct basal body functions in Tetrahymena. Mol Biol Cell 2011; 22:2221-34. [PMID: 21562224 PMCID: PMC3128525 DOI: 10.1091/mbc.e11-02-0151] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Revised: 04/15/2011] [Accepted: 04/29/2011] [Indexed: 11/11/2022] Open
Abstract
The basal body is a microtubule-organizing center responsible for organizing the cilium, a structure important for cell locomotion and sensing of the surrounding environment. A widely conserved basal body component is the Ca(2+)-binding protein centrin. Analyses of centrin function suggest a role in basal body assembly and stability; however, its molecular mechanisms remain unclear. Here we describe a mutagenic strategy to study the function and essential nature of the various structural features of Cen1 in the ciliate Tetrahymena. We find that the two domains of Cen1 are both essential, and examination of strains containing mutant CEN1 alleles indicates that there are two predominant basal body phenotypes: misorientation of newly assembled basal bodies and stability defects. The results also show that the two domains of Cen1 are able to bind Ca(2+) and that perturbation of Ca(2+) binding affects Cen1 function. In all, the data suggest that the two domains of Cen1 have distinct functions.
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Affiliation(s)
- Tyson Vonderfecht
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado–Boulder, Boulder, CO 80309
| | - Alexander J. Stemm-Wolf
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado–Boulder, Boulder, CO 80309
| | | | - Thomas H. Giddings
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado–Boulder, Boulder, CO 80309
| | - Janet B. Meehl
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado–Boulder, Boulder, CO 80309
| | - Mark Winey
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado–Boulder, Boulder, CO 80309
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Miron S, Durand D, Chilom C, Pérez J, Craescu CT. Binding of calcium, magnesium, and target peptides to Cdc31, the centrin of yeast Saccharomyces cerevisiae. Biochemistry 2011; 50:6409-22. [PMID: 21714500 DOI: 10.1021/bi200518d] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cdc31, the Saccharomyces cerevisiae centrin, is an EF-hand calcium-binding protein essential for the cell division and mRNA nuclear export. We used biophysical techniques to investigate its calcium, magnesium, and protein target binding properties as well as their conformations in solution. We show here that Cdc31 displays one Ca(2+)/Mg(2+) mixed site in the N-terminal domain and two low-affinity Ca(2+) sites in the C-terminal domain. The affinity of Cdc31 for different natural target peptides (from Kar1, Sfi1, Sac3) that we obtained by isothermal titration calorimetry shows weakly Ca(2+), but also Mg(2+) dependence. The characteristics of target surface binding were shown to be similar; we highlight that the 1-4 hydrophobic amino acid motif, in a stable amphipathic α-helix, is critical for binding. Ca(2+) and Mg(2+) binding increase the α-helix content and stabilize the structure. Analysis of small-angle X-ray scattering experiments revealed that N- and C-terminal domains are not individualized in apo-Cdc31; in contrast, they are separated in the Mg(2+) state, creating a groove in the middle of the molecule that is occupied by the target peptide in the liganded form. Consequently, Mg(2+) seems to have consequences on Cdc31's function and could be important to stimulate interactions in resting cells.
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Affiliation(s)
- Simona Miron
- Institut Curie Centre de Recherche, Centre Universitaire Paris-Sud, 91405 Orsay Cedex, France.
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29
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CDC25B associates with a centrin 2-containing complex and is involved in maintaining centrosome integrity. Biol Cell 2011; 103:55-68. [PMID: 21091437 PMCID: PMC3025493 DOI: 10.1042/bc20100111] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Background information. CDC25 (cell division cycle 25) phosphatases function as activators of CDK (cyclin-dependent kinase)–cyclin complexes to regulate progression through the CDC. We have recently identified a pool of CDC25B at the centrosome of interphase cells that plays a role in regulating centrosome numbers. Results. In the present study, we demonstrate that CDC25B forms a close association with Ctn (centrin) proteins at the centrosome. This interaction involves both N- and C-terminal regions of CDC25B and requires CDC25B binding to its CDK–cyclin substrates. However, the interaction is not dependent on the enzyme activity of CDC25B. Although CDC25B appears to bind indirectly to Ctn2, this association is pertinent to CDC25B localization at the centrosome. We further demonstrate that CDC25B plays a role in maintaining the overall integrity of the centrosome, by regulating the centrosome levels of multiple centrosome proteins, including that of Ctn2. Conclusions. Our results therefore suggest that CDC25B associates with a Ctn2-containing multiprotein complex in the cytoplasm, which targets it to the centrosome, where it plays a role in maintaining the centrosome levels of Ctn2 and a number of other centrosome components.
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30
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Peled JU, Sellers RS, Iglesias-Ussel MD, Shin DM, Montagna C, Zhao C, Li Z, Edelmann W, Morse HC, Scharff MD. Msh6 protects mature B cells from lymphoma by preserving genomic stability. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 177:2597-608. [PMID: 20934970 DOI: 10.2353/ajpath.2010.100234] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Most human B-cell non-Hodgkin's lymphomas arise from germinal centers. Within these sites, the mismatch repair factor MSH6 participates in antibody diversification. Reminiscent of the neoplasms arising in patients with Lynch syndrome III, mice deficient in MSH6 die prematurely of lymphoma. In this study, we characterized the B-cell tumors in MSH6-deficient mice and describe their histological, immunohistochemical, and molecular features, which include moderate microsatellite instability. Based on histological markers and gene expression, the tumor cells seem to be at or beyond the germinal center stage. The simultaneous loss of MSH6 and of activation-induced cytidine deaminase did not appreciably affect the survival of these animals, suggesting that these germinal center-like tumors arose by an activation-induced cytidine deaminase-independent pathway. We conclude that MSH6 protects B cells from neoplastic transformation by preserving genomic stability.
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Affiliation(s)
- Jonathan U Peled
- Cell Biology Department, Chanin 403, Albert Einstein College of Medicine, 1300 Morris Park Ave., Bronx, NY 10461, USA
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31
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Radu L, Durussel I, Assairi L, Blouquit Y, Miron S, Cox JA, Craescu CT. Scherffelia dubia Centrin Exhibits a Specific Mechanism for Ca2+-Controlled Target Binding. Biochemistry 2010; 49:4383-94. [DOI: 10.1021/bi901764m] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Laura Radu
- Institut Curie Centre de Recherche, Centre Universitaire Paris-Sud, 91405 Orsay Cedex, France
- INSERM U759, Centre Universitaire Paris-Sud, 91405 Orsay Cedex, France
| | - Isabelle Durussel
- Department of Biochemistry, University of Geneva, Geneva 4, Switzerland
| | - Liliane Assairi
- Institut Curie Centre de Recherche, Centre Universitaire Paris-Sud, 91405 Orsay Cedex, France
- INSERM U759, Centre Universitaire Paris-Sud, 91405 Orsay Cedex, France
| | - Yves Blouquit
- Institut Curie Centre de Recherche, Centre Universitaire Paris-Sud, 91405 Orsay Cedex, France
- INSERM U759, Centre Universitaire Paris-Sud, 91405 Orsay Cedex, France
| | - Simona Miron
- Institut Curie Centre de Recherche, Centre Universitaire Paris-Sud, 91405 Orsay Cedex, France
- INSERM U759, Centre Universitaire Paris-Sud, 91405 Orsay Cedex, France
| | - Jos A. Cox
- Department of Biochemistry, University of Geneva, Geneva 4, Switzerland
| | - Constantin T. Craescu
- Institut Curie Centre de Recherche, Centre Universitaire Paris-Sud, 91405 Orsay Cedex, France
- INSERM U759, Centre Universitaire Paris-Sud, 91405 Orsay Cedex, France
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32
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Martinez-Sanz J, Kateb F, Assairi L, Blouquit Y, Bodenhausen G, Abergel D, Mouawad L, Craescu CT. Structure, Dynamics and Thermodynamics of the Human Centrin 2/hSfi1 Complex. J Mol Biol 2010; 395:191-204. [DOI: 10.1016/j.jmb.2009.10.041] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Revised: 10/16/2009] [Accepted: 10/17/2009] [Indexed: 10/20/2022]
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Centrin 2 localizes to the vertebrate nuclear pore and plays a role in mRNA and protein export. Mol Cell Biol 2008; 28:1755-69. [PMID: 18172010 DOI: 10.1128/mcb.01697-07] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Centrins in vertebrates have traditionally been associated with microtubule-nucleating centers such as the centrosome. Unexpectedly, we found centrin 2 to associate biochemically with nucleoporins, including the Xenopus laevis Nup107-160 complex, a critical subunit of the vertebrate nuclear pore in interphase and of the kinetochores and spindle poles in mitosis. Immunofluorescence of Xenopus cells and in vitro reconstituted nuclei indeed revealed centrin 2 localized at the nuclear pores. Use of the mild detergent digitonin in immunofluorescence also allowed centrin 2 to be clearly visualized at the nuclear pores of human cells. Disruption of nuclear pores using RNA interference of the pore assembly protein ELYS/MEL-28 resulted in a specific decrease of centrin 2 at the nuclear rim of HeLa cells. Functionally, excess expression of either the N- or C-terminal calcium-binding domains of human centrin 2 caused a dominant-negative effect on both mRNA and protein export, leaving protein import intact. The mRNA effect mirrors that found for the Saccharomyes cerevisiae centrin Cdc31p at the yeast nuclear pore, a role until now thought to be unique to yeast. We conclude that in vertebrates, centrin 2 interacts with major subunits of the nuclear pore, exhibits nuclear pore localization, and plays a functional role in multiple nuclear export pathways.
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34
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Okhrimenko O, Jelesarov I. A survey of the year 2006 literature on applications of isothermal titration calorimetry. J Mol Recognit 2008; 21:1-19. [DOI: 10.1002/jmr.859] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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35
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Gogendeau D, Klotz C, Arnaiz O, Malinowska A, Dadlez M, de Loubresse NG, Ruiz F, Koll F, Beisson J. Functional diversification of centrins and cell morphological complexity. J Cell Sci 2007; 121:65-74. [PMID: 18057024 DOI: 10.1242/jcs.019414] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In addition to their key role in the duplication of microtubule organising centres (MTOCs), centrins are major constituents of diverse MTOC-associated contractile arrays. A centrin partner, Sfi1p, has been characterised in yeast as a large protein carrying multiple centrin-binding sites, suggesting a model for centrin-mediated Ca2+-induced contractility and for the duplication of MTOCs. In vivo validation of this model has been obtained in Paramecium, which possesses an extended contractile array - the infraciliary lattice (ICL) - essentially composed of centrins and a huge Sfi1p-like protein, PtCenBP1p, which is essential for ICL assembly and contractility. The high molecular diversity revealed here by the proteomic analysis of the ICL, including ten subfamilies of centrins and two subfamilies of Sf1p-like proteins, led us to address the question of the functional redundancy, either between the centrin-binding proteins or between the centrin subfamilies. We show that all are essential for ICL biogenesis. The two centrin-binding protein subfamilies and nine of the centrin subfamilies are ICL specific and play a role in its molecular and supramolecular architecture. The tenth and most conserved centrin subfamily is present at three cortical locations (ICL, basal bodies and contractile vacuole pores) and might play a role in coordinating duplication and positioning of cortical organelles.
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Affiliation(s)
- Delphine Gogendeau
- CNRS, Centre de Génétique Moléculaire, UPR 2167, Gif-sur-Yvette, F-91198, France.
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36
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Charbonnier JB, Renaud E, Miron S, Le Du MH, Blouquit Y, Duchambon P, Christova P, Shosheva A, Rose T, Angulo JF, Craescu CT. Structural, Thermodynamic, and Cellular Characterization of Human Centrin 2 Interaction with Xeroderma Pigmentosum Group C Protein. J Mol Biol 2007; 373:1032-46. [PMID: 17897675 DOI: 10.1016/j.jmb.2007.08.046] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2007] [Revised: 08/17/2007] [Accepted: 08/20/2007] [Indexed: 11/25/2022]
Abstract
Human centrin 2 (HsCen2), an EF-hand calcium binding protein, plays a regulatory role in the DNA damage recognition during the first steps of the nucleotide excision repair. This biological action is mediated by the binding to a short fragment (N847-R863) from the C-terminal region of xeroderma pigmentosum group C (XPC) protein. This work presents a detailed structural and energetic characterization of the HsCen2/XPC interaction. Using a truncated form of HsCen2 we obtained a high resolution (1.8 A) X-ray structure of the complex with the peptide N847-R863 from XPC. Structural and thermodynamic analysis of the interface revealed the existence of both electrostatic and apolar inter-molecular interactions, but the binding energy is mainly determined by the burial of apolar bulky side-chains into the hydrophobic pocket of the HsCen2 C-terminal domain. Binding studies with various peptide variants showed that XPC residues W848 and L851 constitute the critical anchoring side-chains. This enabled us to define a minimal centrin binding peptide variant of five residues, which accounts for about 75% of the total free energy of interaction between the two proteins. Immunofluorescence imaging in HeLa cells demonstrated that HsCen2 binding to the integral XPC protein may be observed in living cells, and is determined by the same interface residues identified in the X-ray structure of the complex. Overexpression of XPC perturbs the cellular distribution of HsCen2, by inducing a translocation of centrin molecules from the cytoplasm to the nucleus. The present data confirm that the in vitro structural features of the centrin/XPC peptide complex are highly relevant to the cellular context.
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Affiliation(s)
- Jean-Baptiste Charbonnier
- Laboratoire de Biologie Structurale et Radiobiologie, iBiTec-S, CEA, Commissariat à l'Energie Atomique, 91191 Gif-sur-Yvette, France
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37
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Gogendeau D, Beisson J, de Loubresse NG, Le Caer JP, Ruiz F, Cohen J, Sperling L, Koll F, Klotz C. An Sfi1p-like centrin-binding protein mediates centrin-based Ca2+ -dependent contractility in Paramecium tetraurelia. EUKARYOTIC CELL 2007; 6:1992-2000. [PMID: 17675401 PMCID: PMC2168399 DOI: 10.1128/ec.00197-07] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The previous characterization and structural analyses of Sfi1p, a Saccharomyces cerevisiae centrin-binding protein essential for spindle pole body duplication, have suggested molecular models to account for centrin-mediated, Ca2+-dependent contractility processes (S. Li, A. M. Sandercock, P. Conduit, C. V. Robinson, R. L. Williams, and J. V. Kilmartin, J. Cell Biol. 173:867-877, 2006). Such processes can be analyzed by using Paramecium tetraurelia, which harbors a large Ca2+ -dependent contractile cytoskeletal network, the infraciliary lattice (ICL). Previous biochemical and genetic studies have shown that the ICL is composed of diverse centrin isoforms and a high-molecular-mass centrin-associated protein, whose reduced size in the démaillé (dem1) mutant correlates with defective organization of the ICL. Using sequences derived from the high-molecular-mass protein to probe the Paramecium genome sequence, we characterized the PtCenBP1 gene, which encodes a 460-kDa protein. PtCenBP1p displays six almost perfect repeats of ca. 427 amino acids (aa) and harbors 89 potential centrin-binding sites with the consensus motif LLX11F/LX2WK/R, similar to the centrin-binding sites of ScSfi1p. The smaller (260-kDa) protein encoded by the dem1 mutant PtCenBP1 allele comprises only two repeats of 427 aa and 46 centrin-binding sites. By using RNA interference and green fluorescent protein fusion experiments, we showed that PtCenBP1p forms the backbone of the ICL and plays an essential role in its assembly and contractility. This study provides the first in vivo demonstration of the role of Sfi1p-like proteins in centrin-mediated Ca2+-dependent contractile processes.
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Affiliation(s)
- Delphine Gogendeau
- Centre de Génétique Moléculaire, UPR 2167, Centre National de la Recherche Scientifique, 91198 Gif-sur-Yvette, France
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38
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Blouquit Y, Duchambon P, Brun E, Marco S, Rusconi F, Sicard-Roselli C. High sensitivity of human centrin 2 toward radiolytical oxidation: C-terminal tyrosinyl residue as the main target. Free Radic Biol Med 2007; 43:216-28. [PMID: 17603931 DOI: 10.1016/j.freeradbiomed.2007.04.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Revised: 03/27/2007] [Accepted: 04/02/2007] [Indexed: 11/15/2022]
Abstract
Centrins are calcium-binding proteins that play a significant role in the maintenance of the centrosomal organization, mainly in the continuity between centrosome and microtubular network. Recent data showed that centrosome duplication abnormalities, like overduplication for example, could be due to hydrogen peroxide, suggesting an important impact of oxidative stress. To challenge this hypothesis, we performed one-electron oxidation experiments with human centrin 2, starting from azide radicals. Our results first revealed several intermolecular cross-links generating dimers, tetramers, hexamers, and higher molecular mass species. Dimers result from covalent bond linking the C-terminal tyrosines of each monomer. Second, the methionyl residue at position 19 was oxidized on the monomeric centrin. Further, electron microscopy experiments on centrin 2 showed a preexisting hexameric organization that was stabilized by covalent bonds as a result of irradiation. Overall, these results show that centrin 2 is highly sensitive to ionizing radiation, which could have important consequences on its biological functions.
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Affiliation(s)
- Yves Blouquit
- INSERM U759, Imagerie Intégrative, Campus Universitaire d'Orsay, Bât. 112, 91405 Orsay Cedex, France
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