1
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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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2
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Evaluation of the association between centrosome amplification in tumor tissue of breast cancer patients and changes in the expression of CETN1 and CNTROB genes. GENE REPORTS 2022. [DOI: 10.1016/j.genrep.2021.101481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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3
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Ma D, Wang F, Wang R, Hu Y, Chen Z, Huang N, Tian Y, Xia Y, Teng J, Chen J. α-/γ-Taxilin are required for centriolar subdistal appendage assembly and microtubule organization. eLife 2022; 11:73252. [PMID: 35119360 PMCID: PMC8816381 DOI: 10.7554/elife.73252] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Accepted: 01/18/2022] [Indexed: 12/31/2022] Open
Abstract
The centrosome composed of a pair of centrioles (mother and daughter) and pericentriolar material, and is mainly responsible for microtubule nucleation and anchorage in animal cells. The subdistal appendage (SDA) is a centriolar structure located at the mother centriole’s subdistal region, and it functions in microtubule anchorage. However, the molecular composition and detailed structure of the SDA remain largely unknown. Here, we identified α-taxilin and γ-taxilin as new SDA components that form a complex via their coiled-coil domains and that serve as a new subgroup during SDA hierarchical assembly. The taxilins’ SDA localization is dependent on ODF2, and α-taxilin recruits CEP170 to the SDA. Functional analyses suggest that α- and γ-taxilin are responsible for SDA structural integrity and centrosomal microtubule anchorage during interphase and for proper spindle orientation during metaphase. Our results shed light on the molecular components and functional understanding of the SDA hierarchical assembly and microtubule organization.
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Affiliation(s)
- Dandan Ma
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing, China
| | - Fulin Wang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing, China
| | - Rongyi Wang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing, China
| | - Yingchun Hu
- Core Facilities College of Life Sciences, Peking University, Beijing, China
| | - Zhiquan Chen
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing, China
| | - Ning Huang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing, China
| | - Yonglu Tian
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing, China
| | - Yuqing Xia
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing, China
| | - Junlin Teng
- Core Facilities College of Life Sciences, Peking University, Beijing, China
| | - Jianguo Chen
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing, China.,Center for Quantitative Biology, Peking University, Beijing, China
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4
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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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5
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Alfaro E, López‐Jiménez P, González‐Martínez J, Malumbres M, Suja JA, Gómez R. PLK1 regulates centrosome migration and spindle dynamics in male mouse meiosis. EMBO Rep 2021; 22:e51030. [PMID: 33615693 PMCID: PMC8025030 DOI: 10.15252/embr.202051030] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 01/14/2021] [Accepted: 01/21/2021] [Indexed: 12/20/2022] Open
Abstract
Cell division requires the regulation of karyokinesis and cytokinesis, which includes an essential role of the achromatic spindle. Although the functions of centrosomes are well characterised in somatic cells, their role during vertebrate spermatogenesis remains elusive. We have studied the dynamics of the meiotic centrosomes in male mouse during both meiotic divisions. Results show that meiotic centrosomes duplicate twice: first duplication occurs in the leptotene/zygotene transition, while the second occurs in interkinesis. The maturation of duplicated centrosomes during the early stages of prophase I and II are followed by their separation and migration to opposite poles to form bipolar spindles I and II. The study of the genetic mouse model Plk1(Δ/Δ) indicates a central role of Polo-like kinase 1 in pericentriolar matrix assembly, in centrosome maturation and migration, and in the formation of the bipolar spindles during spermatogenesis. In addition, in vitro inhibition of Polo-like kinase 1 and Aurora A in organotypic cultures of seminiferous tubules points out to a prominent role of both kinases in the regulation of the formation of meiotic bipolar spindles.
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Affiliation(s)
- Enrique Alfaro
- Departamento de BiologíaFacultad de CienciasUnidad de Biología CelularUniversidad Autónoma de MadridMadridSpain
| | - Pablo López‐Jiménez
- Departamento de BiologíaFacultad de CienciasUnidad de Biología CelularUniversidad Autónoma de MadridMadridSpain
| | | | - Marcos Malumbres
- Cell Division and Cancer GroupSpanish National Cancer Research Centre (CNIO)MadridSpain
| | - José A Suja
- Departamento de BiologíaFacultad de CienciasUnidad de Biología CelularUniversidad Autónoma de MadridMadridSpain
| | - Rocío Gómez
- Departamento de BiologíaFacultad de CienciasUnidad de Biología CelularUniversidad Autónoma de MadridMadridSpain
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6
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Bornens M. A moment at the cell centre. Biol Cell 2019; 111:294-307. [PMID: 31621092 DOI: 10.1111/boc.201900068] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 09/29/2019] [Accepted: 10/01/2019] [Indexed: 11/29/2022]
Abstract
I have been invited by the board of the French Society of Cell Biology (SBCF) to write a text around my presentation in the Symposium 'A day at the Cell Centre', held at the Curie Institute on May 17, 2019, and organized by four of my former students, namely Juliette Azimzadeh, Nathalie Delgehyr, Matthieu Piel and Manuel Théry. I have to thank them warmly for the quality of the science during this day. It was also a moving day for me indeed to listen to so many figures in the field.
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Affiliation(s)
- Michel Bornens
- Institut Curie, PSL Research University, CNRS, Paris, France
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7
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Shan F, Yang X, Diwu Y, Ma H, Tu X. Trypanosoma brucei centrin5 is enriched in the flagellum and interacts with other centrins in a calcium-dependent manner. FEBS Open Bio 2019; 9:1421-1431. [PMID: 31161731 PMCID: PMC6668372 DOI: 10.1002/2211-5463.12683] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 05/24/2019] [Accepted: 05/31/2019] [Indexed: 11/21/2022] Open
Abstract
Centrin is an evolutionarily conserved EF‐hand‐containing protein, which is present in eukaryotic organisms as diverse as algae, yeast, and humans. Centrins are associated with the microtubule‐organizing center and with centrosome‐related structures, such as basal bodies in flagellar and ciliated cells, and the spindle pole body in yeast. Five centrin genes have been identified in Trypanosoma brucei (T. brucei), a protozoan parasite that causes sleeping sickness in humans and nagana in cattle in sub‐Saharan Africa. In the present study, we identified that centrin5 of T. brucei (TbCentrin5) is localized throughout the cytosol and nucleus and enriched in the flagellum. We further identified that TbCentrin5 binds Ca2+ ions with a high affinity and constructed a model of TbCentrin5 bound by Ca2+ ions. Meanwhile, we observed that TbCentrin5 interacts with TbCentrin1, TbCentrin3, and TbCentrin4 and that the interactions are Ca2+‐dependent, suggesting that TbCentrin5 is able to form different complexes with other TbCentrins to participate in relevant cellular processes. Our study provides a foundation for better understanding of the biological roles of TbCentrin5.
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Affiliation(s)
- Fangzhen Shan
- Hefei National Laboratory for Physical Science at Microscale and School of Life Science, University of Science and Technology of China, Hefei, China
| | - Xiao Yang
- Hefei National Laboratory for Physical Science at Microscale and School of Life Science, University of Science and Technology of China, Hefei, China
| | - Yating Diwu
- Hefei National Laboratory for Physical Science at Microscale and School of Life Science, University of Science and Technology of China, Hefei, China
| | - Haoyu Ma
- Hefei National Laboratory for Physical Science at Microscale and School of Life Science, University of Science and Technology of China, Hefei, China
| | - Xiaoming Tu
- Hefei National Laboratory for Physical Science at Microscale and School of Life Science, University of Science and Technology of China, Hefei, China
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8
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Roques M, Stanway RR, Rea EI, Markus R, Brady D, Holder AA, Guttery DS, Tewari R. Plasmodium centrin PbCEN-4 localizes to the putative MTOC and is dispensable for malaria parasite proliferation. Biol Open 2019; 8:bio.036822. [PMID: 30541825 PMCID: PMC6361220 DOI: 10.1242/bio.036822] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Centrins are calmodulin-like phosphoproteins present in the centrosome and play an active role in the duplication, separation and organization of centrosomal structures such as the microtubule-organizing centre (MTOC) during mitosis. They are also major components of the basal body of flagella and cilia. In Plasmodium spp., the parasite that causes malaria, mitosis is closed during asexual replication and the MTOC is embedded within the intact nuclear membrane. The MTOC has been named the centriolar plaque and is similar to the spindle pole body in yeast. In all phases of asexual replication, repeated rounds of nuclear division precede cell division. However, our knowledge of the location and function of centrins during this process is limited. Previous studies have identified four putative centrins in the human parasite Plasmodiumfalciparum. We report here the cellular localization of an alveolate-specific centrin (PbCEN-4) during the atypical cell division of asexual replicative stages, using live cell imaging with the rodent malaria parasite P. berghei as a model system. We show that this centrin forms a multi-protein complex with other centrins, but is dispensable for parasite proliferation. Summary: This study examines the localization of malaria parasite centrin PbCEN4 at the parasite MTOC during closed endomitosis and shows it to be dispensable for proliferation.
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Affiliation(s)
- Magali Roques
- School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
| | - Rebecca R Stanway
- Institute of Cell Biology, University of Bern, Bern 3012, Switzerland
| | - Edward I Rea
- School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
| | - Robert Markus
- School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
| | - Declan Brady
- School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
| | | | - David S Guttery
- The Leicester Cancer Research Centre, College of Life Sciences, University of Leicester, Leicester LE2 7LX, UK
| | - Rita Tewari
- School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
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9
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Ying G, Frederick JM, Baehr W. Deletion of both centrin 2 (CETN2) and CETN3 destabilizes the distal connecting cilium of mouse photoreceptors. J Biol Chem 2019; 294:3957-3973. [PMID: 30647131 DOI: 10.1074/jbc.ra118.006371] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 01/09/2019] [Indexed: 02/03/2023] Open
Abstract
Centrins (CETN1-4) are ubiquitous and conserved EF-hand-family Ca2+-binding proteins associated with the centrosome, basal body, and transition zone. Deletion of CETN1 or CETN2 in mice causes male infertility or dysosmia, respectively, without affecting photoreceptor function. However, it remains unclear to what extent centrins are redundant with each other in photoreceptors. Here, to explore centrin redundancy, we generated Cetn3 GT/GT single-knockout and Cetn2 -/-;Cetn3 GT/GT double-knockout mice. Whereas the Cetn3 deletion alone did not affect photoreceptor function, simultaneous ablation of Cetn2 and Cetn3 resulted in attenuated scotopic and photopic electroretinography (ERG) responses in mice at 3 months of age, with nearly complete retina degeneration at 1 year. Removal of CETN2 and CETN3 activity from the lumen of the connecting cilium (CC) destabilized the photoreceptor axoneme and reduced the CC length as early as postnatal day 22 (P22). In Cetn2 -/-;Cetn3 GT/GT double-knockout mice, spermatogenesis-associated 7 (SPATA7), a key organizer of the photoreceptor-specific distal CC, was depleted gradually, and CETN1 was condensed to the mid-segment of the CC. Ultrastructural analysis revealed that in this double knockout, the axoneme of the CC expanded radially at the distal end, with vertically misaligned outer segment discs and membrane whorls. These observations suggest that CETN2 and CETN3 cooperate in stabilizing the CC/axoneme structure.
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Affiliation(s)
- Guoxin Ying
- From the Department of Ophthalmology, University of Utah Health Science Center, Salt Lake City, Utah 84132,
| | - Jeanne M Frederick
- From the Department of Ophthalmology, University of Utah Health Science Center, Salt Lake City, Utah 84132
| | - Wolfgang Baehr
- From the Department of Ophthalmology, University of Utah Health Science Center, Salt Lake City, Utah 84132, .,the Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, Utah 84112, and.,the Department of Biology, University of Utah, Salt Lake City, Utah 84132
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10
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Fisk HA, Thomas JL, Nguyen TB. Breaking Bad: Uncoupling of Modularity in Centriole Biogenesis and the Generation of Excess Centrioles in Cancer. Results Probl Cell Differ 2019; 67:391-411. [PMID: 31435805 DOI: 10.1007/978-3-030-23173-6_17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Centrosomes are tiny yet complex cytoplasmic structures that perform a variety of roles related to their ability to act as microtubule-organizing centers. Like the genome, centrosomes are single copy structures that undergo a precise semi-conservative replication once each cell cycle. Precise replication of the centrosome is essential for genome integrity, because the duplicated centrosomes will serve as the poles of a bipolar mitotic spindle, and any number of centrosomes other than two will lead to an aberrant spindle that mis-segregates chromosomes. Indeed, excess centrosomes are observed in a variety of human tumors where they generate abnormal spindles in situ that are thought to participate in tumorigenesis by driving genomic instability. At the heart of the centrosome is a pair of centrioles, and at the heart of centrosome duplication is the replication of this centriole pair. Centriole replication proceeds through a complex macromolecular assembly process. However, while centrosomes may contain as many as 500 proteins, only a handful of proteins have been shown to be essential for centriole replication. Our observations suggest that centriole replication is a modular, bottom-up process that we envision akin to building a house; the proper site of assembly is identified, a foundation is assembled at that site, and subsequent modules are added on top of the foundation. Here, we discuss the data underlying our view of modularity in the centriole assembly process, and suggest that non-essential centriole assembly factors take on greater importance in cancer cells due to their function in coordination between centriole modules, using the Monopolar spindles 1 protein kinase and its substrate Centrin 2 to illustrate our model.
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Affiliation(s)
- Harold A Fisk
- Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA.
| | - Jennifer L Thomas
- Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA
| | - Tan B Nguyen
- Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA
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11
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Solution structure of TbCentrin4 from Trypanosoma brucei and its interactions with Ca 2+ and other centrins. Biochem J 2018; 475:3763-3778. [PMID: 30389845 DOI: 10.1042/bcj20180752] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 10/30/2018] [Accepted: 11/01/2018] [Indexed: 12/17/2022]
Abstract
Centrin is a conserved calcium-binding protein that plays an important role in diverse cellular biological processes such as ciliogenesis, gene expression, DNA repair and signal transduction. In Trypanosoma brucei, TbCentrin4 is mainly localized in basal bodies and bi-lobe structure, and is involved in the processes coordinating karyokinesis and cytokinesis. In the present study, we solved the solution structure of TbCentrin4 using NMR (nuclear magnetic resonance) spectroscopy. TbCentrin4 contains four EF-hand motifs consisting of eight α-helices. Isothermal titration calorimetry experiment showed that TbCentrin4 has a strong Ca2+ binding ability. NMR chemical shift perturbation indicated that TbCentrin4 binds to Ca2+ through its C-terminal domain composed of EF-hand 3 and 4. Meanwhile, we revealed that TbCentrin4 undergoes a conformational change and self-assembly induced by high concentration of Ca2+ Intriguingly, localization of TbCentrin4 was dispersed or disappeared from basal bodies and the bi-lobe structure when the cells were treated with Ca2+ in vivo, implying the influence of Ca2+ on the cellular functions of TbCentrin4. Besides, we observed the interactions between TbCentrin4 and other Tbcentrins and revealed that the interactions are Ca2+ dependent. Our findings provide a structural basis for better understanding the biological functions of TbCentrin4 in the relevant cellular processes.
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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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13
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Sydor AM, Coyaud E, Rovelli C, Laurent E, Liu H, Raught B, Mennella V. PPP1R35 is a novel centrosomal protein that regulates centriole length in concert with the microcephaly protein RTTN. eLife 2018; 7:37846. [PMID: 30168418 PMCID: PMC6141234 DOI: 10.7554/elife.37846] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 08/21/2018] [Indexed: 01/02/2023] Open
Abstract
Centrosome structure, function, and number are finely regulated at the cellular level to ensure normal mammalian development. Here, we characterize PPP1R35 as a novel bona fide centrosomal protein and demonstrate that it is critical for centriole elongation. Using quantitative super-resolution microscopy mapping and live-cell imaging we show that PPP1R35 is a resident centrosomal protein located in the proximal lumen above the cartwheel, a region of the centriole that has eluded detailed characterization. Loss of PPP1R35 function results in decreased centrosome number and shortened centrioles that lack centriolar distal and microtubule wall associated proteins required for centriole elongation. We further demonstrate that PPP1R35 acts downstream of, and forms a complex with, RTTN, a microcephaly protein required for distal centriole elongation. Altogether, our study identifies a novel step in the centriole elongation pathway centered on PPP1R35 and elucidates downstream partners of the microcephaly protein RTTN.
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Affiliation(s)
| | - Etienne Coyaud
- Princess Margaret Cancer Centre, University Health Network, Toronto, Canada
| | - Cristina Rovelli
- Cell Biology Program, The Hospital for Sick Children, Toronto, Canada
| | - Estelle Laurent
- Princess Margaret Cancer Centre, University Health Network, Toronto, Canada
| | - Helen Liu
- Cell Biology Program, The Hospital for Sick Children, Toronto, Canada
| | - Brian Raught
- Princess Margaret Cancer Centre, University Health Network, Toronto, Canada.,Department of Medical Biophysics, University of Toronto, Ontario, Canada
| | - Vito Mennella
- Cell Biology Program, The Hospital for Sick Children, Toronto, Canada.,Department of Biochemistry, University of Toronto, Ontario, Canada
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14
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Joseph N, Al-Jassar C, Johnson CM, Andreeva A, Barnabas DD, Freund SMV, Gergely F, van Breugel M. Disease-Associated Mutations in CEP120 Destabilize the Protein and Impair Ciliogenesis. Cell Rep 2018; 23:2805-2818. [PMID: 29847808 PMCID: PMC5990496 DOI: 10.1016/j.celrep.2018.04.100] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 03/15/2018] [Accepted: 04/24/2018] [Indexed: 01/10/2023] Open
Abstract
Ciliopathies are a group of genetic disorders caused by a failure to form functional cilia. Due to a lack of structural information, it is currently poorly understood how ciliopathic mutations affect protein functionality to give rise to the underlying disease. Using X-ray crystallography, we show that the ciliopathy-associated centriolar protein CEP120 contains three C2 domains. The point mutations V194A and A199P, which cause Joubert syndrome (JS) and Jeune asphyxiating thoracic dystrophy (JATD), respectively, both reduce the thermostability of the second C2 domain by targeting residues that point toward its hydrophobic core. Genome-engineered cells homozygous for these mutations have largely normal centriole numbers but show reduced CEP120 levels, compromised recruitment of distal centriole markers, and deficient cilia formation. Our results provide insight into the disease mechanism of two ciliopathic mutations in CEP120, identify putative binding partners of CEP120 C2B, and suggest a complex genotype-phenotype relation of the CEP120 ciliopathy alleles.
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Affiliation(s)
- Nimesh Joseph
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK
| | - Caezar Al-Jassar
- Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Christopher M Johnson
- Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Antonina Andreeva
- Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Deepak D Barnabas
- Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Stefan M V Freund
- Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Fanni Gergely
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK.
| | - Mark van Breugel
- Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK.
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15
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Ordulu Z, Kammin T, Brand H, Pillalamarri V, Redin CE, Collins RL, Blumenthal I, Hanscom C, Pereira S, Bradley I, Crandall BF, Gerrol P, Hayden MA, Hussain N, Kanengisser-Pines B, Kantarci S, Levy B, Macera MJ, Quintero-Rivera F, Spiegel E, Stevens B, Ulm JE, Warburton D, Wilkins-Haug LE, Yachelevich N, Gusella JF, Talkowski ME, Morton CC. Structural Chromosomal Rearrangements Require Nucleotide-Level Resolution: Lessons from Next-Generation Sequencing in Prenatal Diagnosis. Am J Hum Genet 2016; 99:1015-1033. [PMID: 27745839 PMCID: PMC5097935 DOI: 10.1016/j.ajhg.2016.08.022] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Accepted: 08/26/2016] [Indexed: 12/27/2022] Open
Abstract
In this exciting era of "next-gen cytogenetics," integrating genomic sequencing into the prenatal diagnostic setting is possible within an actionable time frame and can provide precise delineation of balanced chromosomal rearrangements at the nucleotide level. Given the increased risk of congenital abnormalities in newborns with de novo balanced chromosomal rearrangements, comprehensive interpretation of breakpoints could substantially improve prediction of phenotypic outcomes and support perinatal medical care. Herein, we present and evaluate sequencing results of balanced chromosomal rearrangements in ten prenatal subjects with respect to the location of regulatory chromatin domains (topologically associated domains [TADs]). The genomic material from all subjects was interpreted to be "normal" by microarray analyses, and their rearrangements would not have been detected by cell-free DNA (cfDNA) screening. The findings of our systematic approach correlate with phenotypes of both pregnancies with untoward outcomes (5/10) and with healthy newborns (3/10). Two pregnancies, one with a chromosomal aberration predicted to be of unknown clinical significance and another one predicted to be likely benign, were terminated prior to phenotype-genotype correlation (2/10). We demonstrate that the clinical interpretation of structural rearrangements should not be limited to interruption, deletion, or duplication of specific genes and should also incorporate regulatory domains of the human genome with critical ramifications for the control of gene expression. As detailed in this study, our molecular approach to both detecting and interpreting the breakpoints of structural rearrangements yields unparalleled information in comparison to other commonly used first-tier diagnostic methods, such as non-invasive cfDNA screening and microarray analysis, to provide improved genetic counseling for phenotypic outcome in the prenatal setting.
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Affiliation(s)
- Zehra Ordulu
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Tammy Kammin
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Harrison Brand
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Boston, MA 02142, USA
| | - Vamsee Pillalamarri
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Claire E Redin
- Harvard Medical School, Boston, MA 02115, USA; Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Boston, MA 02142, USA
| | - Ryan L Collins
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Ian Blumenthal
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Carrie Hanscom
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Shahrin Pereira
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - India Bradley
- Department of Psychiatry, Prenatal Diagnosis Center, David Geffen School of Medicine, University of California, Los Angeles, Medical Plaza, Los Angeles, CA 90095, USA
| | - Barbara F Crandall
- Department of Psychiatry, Prenatal Diagnosis Center, David Geffen School of Medicine, University of California, Los Angeles, Medical Plaza, Los Angeles, CA 90095, USA
| | - Pamela Gerrol
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Mark A Hayden
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Naveed Hussain
- Department of Pediatrics, Connecticut Children's Medical Center, University of Connecticut, Farmington, CT 06030, USA
| | | | - Sibel Kantarci
- Department of Pathology and Laboratory Medicine, UCLA Clinical Genomics Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Brynn Levy
- Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - Michael J Macera
- New York Presbyterian Hospital, Columbia University Medical Center, New York, NY 10032, USA
| | - Fabiola Quintero-Rivera
- Department of Pathology and Laboratory Medicine, UCLA Clinical Genomics Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Erica Spiegel
- Department of Maternal Fetal Medicine, Columbia University Medical Center, New York, NY 10032, USA
| | - Blair Stevens
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Texas Medical School at Houston, Houston, TX 77030, USA
| | - Janet E Ulm
- Regional Obstetrical Consultants, Chattanooga, TN 37403, USA
| | - Dorothy Warburton
- Department of Genetics and Development, Columbia University, New York, NY 10032, USA; Department of Pediatrics, Columbia University, New York, NY 10032, USA
| | - Louise E Wilkins-Haug
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Naomi Yachelevich
- Department of Pediatrics, Clinical Genetics Services, New York University School of Medicine, New York, NY 10003, USA
| | - James F Gusella
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Boston, MA 02142, USA; Department of Genetics, Harvard Medical School, Boson, MA 02115, USA
| | - Michael E Talkowski
- Harvard Medical School, Boston, MA 02115, USA; Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Boston, MA 02142, USA; Departments of Psychiatry and Pathology, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Cynthia C Morton
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA; Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Boston, MA 02142, USA; Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA; Division of Evolution and Genomic Science, School of Biological Sciences, University of Manchester, Manchester Academic Health Science Center, Manchester 03101, UK.
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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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Sawant DB, Majumder S, Perkins JL, Yang CH, Eyers PA, Fisk HA. Centrin 3 is an inhibitor of centrosomal Mps1 and antagonizes centrin 2 function. Mol Biol Cell 2015; 26:3741-53. [PMID: 26354417 PMCID: PMC4626060 DOI: 10.1091/mbc.e14-07-1248] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 09/04/2015] [Indexed: 11/11/2022] Open
Abstract
Centrins are a family of small, calcium-binding proteins with diverse cellular functions that play an important role in centrosome biology. We previously identified centrin 2 and centrin 3 (Cetn2 and Cetn3) as substrates of the protein kinase Mps1. However, although Mps1 phosphorylation sites control the function of Cetn2 in centriole assembly and promote centriole overproduction, Cetn2 and Cetn3 are not functionally interchangeable, and we show here that Cetn3 is both a biochemical inhibitor of Mps1 catalytic activity and a biological inhibitor of centrosome duplication. In vitro, Cetn3 inhibits Mps1 autophosphorylation at Thr-676, a known site of T-loop autoactivation, and interferes with Mps1-dependent phosphorylation of Cetn2. The cellular overexpression of Cetn3 attenuates the incorporation of Cetn2 into centrioles and centrosome reduplication, whereas depletion of Cetn3 generates extra centrioles. Finally, overexpression of Cetn3 reduces Mps1 Thr-676 phosphorylation at centrosomes, and mimicking Mps1-dependent phosphorylation of Cetn2 bypasses the inhibitory effect of Cetn3, suggesting that the biological effects of Cetn3 are due to the inhibition of Mps1 function at centrosomes.
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Affiliation(s)
- Dwitiya B Sawant
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210
| | - Shubhra Majumder
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210
| | - Jennifer L Perkins
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210
| | - Ching-Hui Yang
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210
| | - Patrick A Eyers
- Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, United Kingdom
| | - Harold A Fisk
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210
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18
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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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19
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Bornens M, Gönczy P. Centrosomes back in the limelight. Philos Trans R Soc Lond B Biol Sci 2015; 369:rstb.2013.0452. [PMID: 25047606 DOI: 10.1098/rstb.2013.0452] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Affiliation(s)
- Michel Bornens
- UMR 144 CNRS-Institut CURIE, 26 rue d'Ulm 75 248, PARIS Cedex 05, France
| | - Pierre Gönczy
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL) Lausanne, Switzerland
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20
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Arquint C, Gabryjonczyk AM, Nigg EA. Centrosomes as signalling centres. Philos Trans R Soc Lond B Biol Sci 2015; 369:rstb.2013.0464. [PMID: 25047618 DOI: 10.1098/rstb.2013.0464] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Centrosomes-as well as the related spindle pole bodies (SPBs) of yeast-have been extensively studied from the perspective of their microtubule-organizing roles. Moreover, the biogenesis and duplication of these organelles have been the subject of much attention, and the importance of centrosomes and the centriole-ciliary apparatus for human disease is well recognized. Much less developed is our understanding of another facet of centrosomes and SPBs, namely their possible role as signalling centres. Yet, many signalling components, including kinases and phosphatases, have been associated with centrosomes and spindle poles, giving rise to the hypothesis that these organelles might serve as hubs for the integration and coordination of signalling pathways. In this review, we discuss a number of selected studies that bear on this notion. We cover different processes (cell cycle control, development, DNA damage response) and organisms (yeast, invertebrates and vertebrates), but have made no attempt to be comprehensive. This field is still young and although the concept of centrosomes and SPBs as signalling centres is attractive, it remains primarily a concept-in need of further scrutiny. We hope that this review will stimulate thought and experimentation.
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Affiliation(s)
- Christian Arquint
- Biozentrum, University of Basel, Klingelbergstrasse 50/70, 4056 Basel, Switzerland
| | | | - Erich A Nigg
- Biozentrum, University of Basel, Klingelbergstrasse 50/70, 4056 Basel, Switzerland
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21
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Linge A, Maurya P, Friedrich K, Baretton GB, Kelly S, Henry M, Clynes M, Larkin A, Meleady P. Identification and Functional Validation of RAD23B as a Potential Protein in Human Breast Cancer Progression. J Proteome Res 2014; 13:3212-22. [DOI: 10.1021/pr4012156] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Annett Linge
- National
Institute for Cellular Biotechnology, Dublin City University, Glasnevin, Dublin
9, Ireland
| | - Priyanka Maurya
- National
Institute for Cellular Biotechnology, Dublin City University, Glasnevin, Dublin
9, Ireland
| | - Katrin Friedrich
- Institute
of Pathology, Faculty of Medicine and University Hospital Carl Gustav
Carus, Technische Universität Dresden, Fetscherstraße 74, 01307 Dresden, Germany
| | - Gustavo B. Baretton
- Institute
of Pathology, Faculty of Medicine and University Hospital Carl Gustav
Carus, Technische Universität Dresden, Fetscherstraße 74, 01307 Dresden, Germany
| | - Shane Kelly
- National
Institute for Cellular Biotechnology, Dublin City University, Glasnevin, Dublin
9, Ireland
| | - Michael Henry
- National
Institute for Cellular Biotechnology, Dublin City University, Glasnevin, Dublin
9, Ireland
| | - Martin Clynes
- National
Institute for Cellular Biotechnology, Dublin City University, Glasnevin, Dublin
9, Ireland
| | - Annemarie Larkin
- National
Institute for Cellular Biotechnology, Dublin City University, Glasnevin, Dublin
9, Ireland
| | - Paula Meleady
- National
Institute for Cellular Biotechnology, Dublin City University, Glasnevin, Dublin
9, Ireland
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22
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Structural and thermodynamic studies of two centrin isoforms from Blastocladiella emersonii upon calcium binding. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:2823-31. [DOI: 10.1016/j.bbapap.2013.10.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 09/30/2013] [Accepted: 10/06/2013] [Indexed: 11/22/2022]
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23
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Dantas TJ, Daly OM, Conroy PC, Tomas M, Wang Y, Lalor P, Dockery P, Ferrando-May E, Morrison CG. Calcium-binding capacity of centrin2 is required for linear POC5 assembly but not for nucleotide excision repair. PLoS One 2013; 8:e68487. [PMID: 23844208 PMCID: PMC3699651 DOI: 10.1371/journal.pone.0068487] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 05/29/2013] [Indexed: 12/25/2022] Open
Abstract
Centrosomes, the principal microtubule-organising centres in animal cells, contain centrins, small, conserved calcium-binding proteins unique to eukaryotes. Centrin2 binds to xeroderma pigmentosum group C protein (XPC), stabilising it, and its presence slightly increases nucleotide excision repair (NER) activity in vitro. In previous work, we deleted all three centrin isoforms present in chicken DT40 cells and observed delayed repair of UV-induced DNA lesions, but no centrosome abnormalities. Here, we explore how centrin2 controls NER. In the centrin null cells, we expressed centrin2 mutants that cannot bind calcium or that lack sites for phosphorylation by regulatory kinases. Expression of any of these mutants restored the UV sensitivity of centrin null cells to normal as effectively as expression of wild-type centrin. However, calcium-binding-deficient and T118A mutants showed greatly compromised localisation to centrosomes. XPC recruitment to laser-induced UV-like lesions was only slightly slower in centrin-deficient cells than in controls, and levels of XPC and its partner HRAD23B were unaffected by centrin deficiency. Interestingly, we found that overexpression of the centrin interactor POC5 leads to the assembly of linear, centrin-dependent structures that recruit other centrosomal proteins such as PCM-1 and NEDD1. Together, these observations suggest that assembly of centrins into complex structures requires calcium binding capacity, but that such assembly is not required for centrin activity in NER.
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Affiliation(s)
- Tiago J. Dantas
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland
| | - Owen M. Daly
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland
| | - Pauline C. Conroy
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland
| | - Martin Tomas
- Bioimaging Center, University of Konstanz, Konstanz, Germany
- Department of Physics, Center for Applied Photonics, University of Konstanz, Konstanz, Germany
| | - Yifan Wang
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland
| | - Pierce Lalor
- Anatomy, School of Medicine, National University of Ireland Galway, Galway, Ireland
| | - Peter Dockery
- Anatomy, School of Medicine, National University of Ireland Galway, Galway, Ireland
| | | | - Ciaran G. Morrison
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland
- * E-mail:
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24
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Kim JJ, Rajagopalan K, Hussain B, Williams BH, Kulkarni P, Mooney SM. CETN1 is a cancer testis antigen with expression in prostate and pancreatic cancers. Biomark Res 2013; 1:22. [PMID: 24252580 PMCID: PMC4177615 DOI: 10.1186/2050-7771-1-22] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2013] [Accepted: 06/03/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The Cancer Testis Antigens (CTAs) are a group of genes that are highly expressed in the normal testis and several types of cancer. Due to their restricted expression in normal adult tissues, CTAs have been attractive targets for immunotherapy and biomarker development. In this work, we discovered that Centrin 1 (CETN1) which is found in the centrosome of all eukaryotes, may be a member of this group and is highly expressed in prostate and pancreatic cancer. Three members of the centrin family of calcium binding proteins (CETN) are localized to the centrosome in all eukaryotes with CDC31 being the sole yeast homolog. CETN1 is a retrogene that probably arose from a retrotransposition of CETN2, an X-linked gene. A previous mouse study shows that CETN1 is expressed solely in the testis, while CETN2 is expressed in all organs. RESULTS In this work, we show that CETN1 is a new member of the growing group of CTAs. Through the mining of publicly available microarray data, we discovered that human CETN1 expression but not CETN2 or CETN3 is restricted to the testis. In fact, CETN1 is actually down-regulated in testicular malignancies compared to normal testis. Using q-PCR, CETN1 expression is shown to be highly up-regulated in cancer of the prostate and in pancreatic xenografts. Unexpectedly however, CETN1 expression was virtually absent in various cell lines until they were treated with the DNA demethylation agent 5'AZA-2'Deoxycytidine (AZA) but showed no increased expression upon incubation with Histone deacetylase inhibitor Trichostatin-A (TSA) alone. Additionally, like most CTAs, CETN1 appears to be an intrinsically disordered protein which implies that it may occupy a hub position in key protein interaction networks in cancer. Neither CETN1 nor CETN2 could compensate for loss of CDC31 expression in yeast which is analogous to published data for CETN3. CONCLUSIONS This work suggests that CETN1 is a novel CTA with expression in cancer of the prostate and pancreas. In cell lines, the expression is probably regulated by promoter methylation, while the method of regulation in normal adult tissues remains unknown.
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Affiliation(s)
- John J Kim
- Department of Urology, James Buchanan Brady Urological Institute, The Johns Hopkins University, School of Medicine, Baltimore, MD, 21287, USA.
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25
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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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26
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Avasthi P, Scheel JF, Ying G, Frederick JM, Baehr W, Wolfrum U. Germline deletion of Cetn1 causes infertility in male mice. J Cell Sci 2013; 126:3204-13. [PMID: 23641067 DOI: 10.1242/jcs.128587] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Centrins are calmodulin-like Ca(2+)-binding proteins that can be found in all ciliated eukaryotic cells from yeast to mammals. Expressed in male germ cells and photoreceptors, centrin 1 (CETN1) resides in the photoreceptor transition zone and connecting cilium. To identify its function in mammals, we deleted Cetn1 by homologous recombination. Cetn1(-/-) mice were viable and showed no sign of retina degeneration suggesting that CETN1 is nonessential for photoreceptor ciliogenesis or structural maintenance. Phototransduction components localized normally to the Cetn1(-/-) photoreceptor outer segments, and loss of CETN1 had no effect on light-induced translocation of transducin to the inner segment. Although Cetn1(-/-) females and Cetn1(+/-) males had normal fertility, Cetn1(-/-) males were infertile. The Cetn1(-/-) testes size was normal, and spermatogonia as well as spermatocytes developed normally. However, spermatids lacked tails suggesting severe defects at the late maturation phase of spermiogenesis. Viable sperm cells were absent and the few surviving spermatozoa were malformed. Light and electron microscopy analyses of Cetn1(-/-) spermatids revealed failures in centriole rearrangement during basal body maturation and in the basal-body-nucleus connection. These results confirm an essential role for CETN1 in late steps of spermiogenesis and spermatid maturation.
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Affiliation(s)
- Prachee Avasthi
- Department of Ophthalmology, University of Utah Health Science Center, 65 Mario Capecchi Drive, Salt Lake City, UT 84132, USA
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Novara F, Rizzo A, Bedini G, Girgenti V, Esposito S, Pantaleoni C, Ciccone R, Sciacca FL, Achille V, Della Mina E, Gana S, Zuffardi O, Estienne M. MEF2C deletions and mutations versus duplications: a clinical comparison. Eur J Med Genet 2013; 56:260-5. [PMID: 23402836 DOI: 10.1016/j.ejmg.2013.01.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Accepted: 01/23/2013] [Indexed: 11/29/2022]
Abstract
5q14.3 deletions including the MEF2C gene have been identified to date using genomic arrays in patients with severe developmental delay or intellectual disability, stereotypic behavior, epilepsy, cerebral malformations and a facial gestalt not really distinctive though characterized by broad and/or high, bulging forehead, upslanting palpebral fissures, flat nasal root and bridge, small, upturned nose, hypotonic small mouth resulting in cupid bow/tented upper lip. MEF2C mutations have been also identified in patients with overlapping phenotype so that it is considered the gene responsible for the 5q14.3 deletion syndrome. To date, one single duplication including MEF2C has been reported in a patient with intellectual disability but its clinical significance remains uncertain also because of the large size of the imbalance. Here we present two further patients with 5q14.3 duplications including MEF2C. Their phenotype indeed suggest the pathogenic effect of the MEF2C duplication although other duplicated genes also brain expressed might contribute to the clinical features. In none of them a clear-cut syndrome can be identified. A comparison between MEF2C deleted/mutated and duplicated patients is also presented.
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Affiliation(s)
- Francesca Novara
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
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Umlauf D, Bonnet J, Waharte F, Fournier M, Stierle M, Fischer B, Brino L, Devys D, Tora L. The human TREX-2 complex is stably associated with the nuclear pore basket. J Cell Sci 2013; 126:2656-67. [DOI: 10.1242/jcs.118000] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
In eukaryotes mRNA export involves many evolutionarily conserved factors that carry the nascent transcript to the nuclear pore complex (NPC). The THO/TREX complex couples transcription to mRNA export and recruits the mRNA export receptor NXF1 for the transport of mRNP particles to the NPC. The transcription and export complex 2 (TREX-2) was suggested to interact with NXF1 and to shuttle between transcription sites and the NPC. Here, we characterize the dynamics of human TREX-2 and show that it stably associates with the NPC basket. Moreover, the association of TREX-2 with the NPC requires the basket nucleoporins NUP153 and TPR, but is independent of transcription. Differential profiles of mRNA nuclear accumulation reveal that TREX-2 functions similarly to basket nucleoporins, but differently from NXF1. Thus, our results show that TREX-2 is an NPC-associated complex in mammalian cells and suggest that it is involved in putative NPC basket-related functions.
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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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30
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Role of centrins 2 and 3 in organelle segregation and cytokinesis in Trypanosoma brucei. PLoS One 2012; 7:e45288. [PMID: 23028908 PMCID: PMC3448667 DOI: 10.1371/journal.pone.0045288] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Accepted: 08/15/2012] [Indexed: 11/19/2022] Open
Abstract
Centrins are calcium binding proteins involved in cell division in eukaryotes. Previously, we have shown that depletion of centrin1 in Trypanosoma brucei (T. brucei) displayed arrested organelle segregation resulting in loss of cytokinesis. In this study we analyzed the role of T. brucei centrin2 (TbCen2) and T. brucei 3 (TbCen3) in the early events of T. brucei procyclic cell cycle. Both the immunofluorescence assay and electron microscopy showed that TbCen2 and 3-deficient cells were enlarged in size with duplicated basal bodies, multinuclei and new flagella that are detached along the length of the cell body. In both TbCen2 and TbCen3 depleted cells segregation of the organelles i.e. basal bodies, kinetoplast and nucleus was disrupted. Further analysis of the cells with defective organelle segregation identified three different sub configurations of organelle mis-segregations (Type 1-3). In addition, in majority of the TbCen2 depleted cells and in nearly half of the TbCen3 depleted cells, the kinetoplasts were enlarged and undivided. The abnormal segregations ultimately led to aborted cytokinesis and hence affected growth in these cells. Therefore, both centrin2 and 3 are involved in organelle segregation similar to centrin1 as was previously observed. In addition, we identified their role in kinetoplast division which may be also linked to overall mis-segregation.
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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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Zhang Y, He CY. Centrins in unicellular organisms: functional diversity and specialization. PROTOPLASMA 2012; 249:459-467. [PMID: 21786168 DOI: 10.1007/s00709-011-0305-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Accepted: 07/10/2011] [Indexed: 05/31/2023]
Abstract
Centrins (also known as caltractins) are conserved, EF hand-containing proteins ubiquitously found in eukaryotes. Similar to calmodulins, the calcium-binding EF hands in centrins fold into two structurally similar domains separated by an alpha-helical linker region, shaping like a dumbbell. The small size (15-22 kDa) and domain organization of centrins and their functional diversity/specialization make them an ideal system to study protein structure-function relationship. Here, we review the work on centrins with a focus on their structures and functions characterized in unicellular organisms.
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Affiliation(s)
- Yu Zhang
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
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Aubusson-Fleury A, Lemullois M, de Loubresse NG, Laligné C, Cohen J, Rosnet O, Jerka-Dziadosz M, Beisson J, Koll F. FOR20, a conserved centrosomal protein, is required for assembly of the transition zone and basal body docking at the cell surface. J Cell Sci 2012; 125:4395-404. [DOI: 10.1242/jcs.108639] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Within the FOP family of centrosomal proteins, the conserved FOR20 protein has been implicated in the control of primary cilium assembly in human cells. To ascertain its role in ciliogenesis, we have investigated the function of its ortholog, PtFOR20p, in a multiciliated unicellular organism, Paramecium. By a combined functional and cytological analysis, we found that PtFOR20p specifically localizes at basal bodies and is required to build the transition zone, a prerequisite to their maturation and docking at the cell surface, hence to ciliogenesis. We also found that PtCen2p (one of the two basal body specific centrins, ortholog of HsCen2) is required to recruit PtFOR20p at the developing basal body and to control its length. In contrast, the other basal body specific centrin, PtCen3p, is not needed for assembly of the transition zone, but is required downstream, for basal body docking. Comparison of the structural defects induced by depletion of PtFOR20p, PtCen2p or PtCen3p respectively illustrates the dual role of the transition zone in the biogenesis of the basal body and in cilium assembly. The multiple potential roles of the transition zone during basal body biogenesis and the evolutionary conserved function of the FOP proteins in microtubule membrane interactions are discussed.
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Dantas TJ, Wang Y, Lalor P, Dockery P, Morrison CG. Defective nucleotide excision repair with normal centrosome structures and functions in the absence of all vertebrate centrins. ACTA ACUST UNITED AC 2011; 193:307-18. [PMID: 21482720 PMCID: PMC3080269 DOI: 10.1083/jcb.201012093] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Centrin-null cells undergo normal division but are highly sensitive to UV irradiation as a result of impaired DNA repair. The principal microtubule-organizing center in animal cells, the centrosome, contains centrin, a small, conserved calcium-binding protein unique to eukaryotes. Several centrin isoforms exist and have been implicated in various cellular processes including nuclear export and deoxyribonucleic acid (DNA) repair. Although centrins are required for centriole/basal body duplication in lower eukaryotes, centrin functions in vertebrate centrosome duplication are less clear. To define these roles, we used gene targeting in the hyperrecombinogenic chicken DT40 cell line to delete all three centrin genes in individual clones. Unexpectedly, centrin-deficient cells underwent normal cellular division with no detectable cell cycle defects. Light and electron microscopy analyses revealed no significant difference in centrosome composition or ultrastructure. However, centrin deficiency made DT40 cells highly sensitive to ultraviolet (UV) irradiation, with Cetn3 deficiency exacerbating the sensitivity of Cetn4/Cetn2 double mutants. DNA damage checkpoints were intact, but repair of UV-induced DNA damage was delayed in centrin nulls. These data demonstrate a role for vertebrate centrin in nucleotide excision repair.
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Affiliation(s)
- Tiago J Dantas
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Galway 091 524 411, Ireland
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Yang CH, Kasbek C, Majumder S, Yusof AM, Fisk HA. Mps1 phosphorylation sites regulate the function of centrin 2 in centriole assembly. Mol Biol Cell 2010; 21:4361-72. [PMID: 20980622 PMCID: PMC3002389 DOI: 10.1091/mbc.e10-04-0298] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
We show that while Centrin2 is dispensable for centriole assembly, it is an Mps1 substrate that stimulates canonical and aberrant centriole assembly by two different Mps1-dependent mechanisms, HsSas-6–dependent and –independent. Centrin2 phosphorylation is also required for the ability of Mps1 to drive production of mature centrioles. The nondegradable Mps1Δ12/13 protein drives centriole overproduction, suggesting that Mps1 phosphorylates a subset of centrosomal proteins to drive the assembly of new centrioles. Here we identify three Mps1 phosphorylation sites within the centriolar protein Centrin 2 (Cetn2). Although centrioles can be assembled in the absence of Cetn2, centriole assembly is attenuated in the absence of Cetn2. While wild-type Cetn2 can compensate for this attenuation, a nonphosphorylatable version cannot. In addition, overexpressing Cetn2 causes Mps1-dependent centriole overproduction that requires each of the three Mps1 phosphorylation sites within Cetn2 and is greatly exacerbated by mimicking phosphorylation at any of these sites. Wild-type Cetn2 generates excess foci that are competent as mitotic spindle poles in HsSas-6–depleted cells, suggesting that Cetn2 can organize a subset of centriolar proteins independently of cartwheels. However, centriole overproduction caused by a phosphomimetic Cetn2 mutant requires HsSas-6, suggesting that Cetn2 phosphorylation stimulates the canonical centriole assembly pathway. Moreover, in the absence of Cetn2, Mps1Δ12/13 cannot drive the production of mature centrioles capable of recruiting γ-Tubulin, and a nonphosphorylatable Cetn2 mutant cannot compensate for this defect and exacerbates Cetn2 depletion. Together, our data suggest that Mps1-dependent phosphorylation of Cetn2 stimulates the canonical centriole assembly pathway.
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Affiliation(s)
- Ching-Hui Yang
- Department of Molecular Genetics, Ohio State University, Columbus OH 43210-1292, USA
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Azimzadeh J, Hergert P, Delouvée A, Euteneuer U, Formstecher E, Khodjakov A, Bornens M. hPOC5 is a centrin-binding protein required for assembly of full-length centrioles. ACTA ACUST UNITED AC 2009; 185:101-14. [PMID: 19349582 PMCID: PMC2700515 DOI: 10.1083/jcb.200808082] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Centrin has been shown to be involved in centrosome biogenesis in a variety of eukaryotes. In this study, we characterize hPOC5, a conserved centrin-binding protein that contains Sfi1p-like repeats. hPOC5 is localized, like centrin, in the distal portion of human centrioles. hPOC5 recruitment to procentrioles occurs during G2/M, a process that continues up to the full maturation of the centriole during the next cell cycle and is correlated with hyperphosphorylation of the protein. In the absence of hPOC5, RPE1 cells arrest in G1 phase, whereas HeLa cells show an extended S phase followed by cell death. We show that hPOC5 is not required for the initiation of procentriole assembly but is essential for building the distal half of centrioles. Interestingly, the hPOC5 family reveals an evolutionary divergence between vertebrates and organisms like Drosophila melanogaster or Caenorhabditis elegans, in which the loss of hPOC5 may correlate with the conspicuous differences in centriolar structure.
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Affiliation(s)
- Juliette Azimzadeh
- Institut Curie, Centre National de la Recherche Scientifique Unité Mixte de Recherche 144, Paris, France
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Dictyostelium discoideum CenB is a bona fide centrin essential for nuclear architecture and centrosome stability. EUKARYOTIC CELL 2009; 8:1106-17. [PMID: 19465563 DOI: 10.1128/ec.00025-09] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Centrins are a family of proteins within the calcium-binding EF-hand superfamily. In addition to their archetypical role at the microtubule organizing center (MTOC), centrins have acquired multiple functionalities throughout the course of evolution. For example, centrins have been linked to different nuclear activities, including mRNA export and DNA repair. Dictyostelium discoideum centrin B is a divergent member of the centrin family. At the amino acid level, DdCenB shows 51% identity with its closest relative and only paralog, DdCenA. Phylogenetic analysis revealed that DdCenB and DdCenA form a well-supported monophyletic and divergent group within the centrin family of proteins. Interestingly, fluorescently tagged versions of DdCenB were not found at the centrosome (in whole cells or in isolated centrosomes). Instead, DdCenB localized to the nuclei of interphase cells. This localization disappeared as the cells entered mitosis, although Dictyostelium cells undergo a closed mitosis in which the nuclear envelope (NE) does not break down. DdCenB knockout cells exhibited aberrant nuclear architecture, characterized by enlarged and deformed nuclei and loss of proper centrosome-nucleus anchoring (observed as NE protrusions). At the centrosome, loss of DdCenB resulted in defects in the organization and morphology of the MTOC and supernumerary centrosomes and centrosome-related bodies. The multiple defects that the loss of DdCenB generated at the centrosome can be explained by its atypical division cycle, transitioning into the NE as it divides at mitosis. On the basis of these findings, we propose that DdCenB is required at interphase to maintain proper nuclear architecture, and before delocalizing from the nucleus, DdCenB is part of the centrosome duplication machinery.
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Yaqin Z, Jiuying F, Aihua L, Binsheng Y. The characterization for the binding of calcium and terbium to Euplotes octocarinatus centrin. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2009; 71:1756-1761. [PMID: 18757233 DOI: 10.1016/j.saa.2008.06.029] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2008] [Revised: 06/11/2008] [Accepted: 06/25/2008] [Indexed: 05/26/2023]
Abstract
Centrin is a member of the EF-hand superfamily that plays critical role in the centrosome duplication and separation. In the present paper, we characterized properties of metal ions binding to Euplotes octocarinatus centrin (EoCen) by fluorescence spectra and circular dichroism (CD) spectra. Changes of fluorescence spectra and alpha-helix contents of EoCen proved that Tb(3+) and Ca(2+) induced great conformational changes of EoCen resulting in exposing hydrophobic surfaces. At pH 7.4, Ca(2+) (and Tb(3+)) bond with EoCen at the ratio of 4:1. Equilibrium experiment indicated that Ca(2+) and Tb(3+) exhibited different binding capabilities for C- and N-terminal domains of protein. C-terminal domain bond with Ca(2+) or Tb(3+) approximately 100-fold more strongly than N-terminal. Aromatic residue-sensitized Tb(3+) energy transfer suggested that site IV bond to Tb(3+) or Ca(2+) more strongly than site III. Based on fluorescence titration curves, we reckoned the conditional binding constants of EoCen site IV quantitatively to be K(IV)=(1.23+/-0.51)x10(8)M(-1) and K(IV)=(6.82+/-0.33)x10(5)M(-1) with Tb(3+) and Ca(2+), respectively. Metal ions bond to EoCen in the order of IV>III>II, I.
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Affiliation(s)
- Zhao Yaqin
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Molecular Science, Shanxi University, Taiyuan 030006, China
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39
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Mahajan B, Selvapandiyan A, Gerald NJ, Majam V, Zheng H, Wickramarachchi T, Tiwari J, Fujioka H, Moch JK, Kumar N, Aravind L, Nakhasi HL, Kumar S. Centrins, Cell Cycle Regulation Proteins in Human Malaria Parasite Plasmodium falciparum. J Biol Chem 2008; 283:31871-83. [DOI: 10.1074/jbc.m800028200] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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40
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Bornens M, Azimzadeh J. Origin and evolution of the centrosome. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 607:119-29. [PMID: 17977464 DOI: 10.1007/978-0-387-74021-8_10] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
In this brief account we specifically address the question of how the plasma membrane-associated basal body/axoneme of the unicellular ancestor of eukaryotes has evolved into the centrosome organelle through the several attempts to multicellularity. We propose that the connection between the flagellar apparatus and the nucleus has been a critical feature for leading to the centriole-based centrosome of metazoa, the Spindle Pole Body of fungi, or to the absence of any centrosome in seed plants. We further suggest that the evolution of this connection could be reflected in the evolution of the centrin proteins. We then review evidence showing that the evolution of the centrosome-based tubulin network has been correlated with the evolution of the cortical actin-based cleavage apparatus. Finally we argue that this coevolution had a major impact on the cell individuation process and on the evolution of multicellular organisms. We conclude that only the metazoan lineage evolved multicellularity without loosing the ancestral association of three basic cellular functions of the basal body/axoneme or the derived centrosome organelle, namely sensation, motion and division.
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Zhao Y, Feng J, Wang Z, Liang A, Yang B. Characterization of melittin binding to Euplotes octocarinatus centrin. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2008; 70:884-887. [PMID: 18054274 DOI: 10.1016/j.saa.2007.10.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2007] [Accepted: 10/03/2007] [Indexed: 05/25/2023]
Abstract
In the presence of 1.0mM Ca2+, the interaction between Euplotes octocarinatus centrin (EoCen) and melittin (ME) was studied by means of fluorescence spectra. In 0.1M N-2-hydroxyethylpiperazine-N-2-ethanesulfonic acid (Hepes) and 150mM NaCl at pH 7.4, fluorescence peak of ME was observed at about 353nm indicating that micro-environment of Tryptophan (Trp) residue in ME was hydrophilic. With the addition of 3.2x10(-4)M calcium saturated EoCen (holoEoCen), the peak of ME was blue-shifted to 339nm, which may be resulted from micro-environmental changes of the peptide. At the same time, fluorescence emission of ME was increased significantly suggesting that new complex of ME-holoEoCen was formed under the experimental conditions. Based on the fluorescence titration curves, the 1:1 stoichiometric ratio of holoEoCen to ME was confirmed. In addition, the conditional binding constant of holoEoCen with ME was calculated to be logKME-holoEoCen=6.59+/-0.14.
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Affiliation(s)
- Yaqin Zhao
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Molecular Science, Shanxi University, Taiyuan 030006, China
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42
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Isolation and Characterization of the Cetn1 Gene from Tufted Deer (Elaphodus cephalophus). Biochem Genet 2008; 46:652-62. [DOI: 10.1007/s10528-008-9179-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2007] [Accepted: 06/02/2008] [Indexed: 10/21/2022]
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43
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Alieva IB, Uzbekov RE. The centrosome is a polyfunctional multiprotein cell complex. BIOCHEMISTRY (MOSCOW) 2008; 73:626-43. [DOI: 10.1134/s0006297908060023] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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44
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Two patients with balanced translocations and autistic disorder: CSMD3 as a candidate gene for autism found in their common 8q23 breakpoint area. Eur J Hum Genet 2008; 16:696-704. [PMID: 18270536 DOI: 10.1038/ejhg.2008.7] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Recent studies estimated a rate of 3-5% of cytogenetic abnormalities involving many different chromosomes in autistic spectrum disorders (ASDs). Here, we report on two unrelated male patients with de novo translocations, autistic behaviour and psychomotor delay. These two patients carry a balanced chromosome translocation t(5;8)(q14.3;q23.3) and t(6;8)(q13;q23.2), respectively. A detailed physical map covering the regions involved in the translocations was constructed using BAC clones mapping on chromosomes 5q14.3, 6q13 and 8q23. Fluorescence in situ hybridisation (FISH) analyses were carried out using these genomic clones. We fine mapped the two translocation breakpoints on chromosomes 8 identifying their position within a short 5 Mb genomic region. Breakpoints on chromosomes 8 in both patients do not interrupt any known gene but both map in a region containing the CSMD3 gene, which thereby can be considered as a candidate for ASDs.
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Trojan P, Krauss N, Choe HW, Giessl A, Pulvermüller A, Wolfrum U. Centrins in retinal photoreceptor cells: regulators in the connecting cilium. Prog Retin Eye Res 2008; 27:237-59. [PMID: 18329314 DOI: 10.1016/j.preteyeres.2008.01.003] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Changes in the intracellular Ca2+ concentration regulate the visual signal transduction cascade directly or more often indirectly through Ca2+-binding proteins. Here we focus on centrins, which are members of a highly conserved subgroup of the EF-hand superfamily of Ca2+-binding proteins in photoreceptor cells of the vertebrate retina. Centrins are commonly associated with centrosome-related structures. In mammalian retinal photoreceptor cells, four centrin isoforms are expressed as prominent components in the connecting cilium linking the light-sensitive outer segment compartment with the metabolically active inner segment compartment. Our data indicate that Ca2+-activated centrin isoforms assemble into protein complexes with the visual heterotrimeric G-protein transducin. This interaction of centrins with transducin is mediated by binding to the betagamma-dimer of the heterotrimeric G-protein. More recent findings show that these interactions of centrins with transducin are reciprocally regulated via site-specific phosphorylations mediated by the protein kinase CK2. The assembly of centrin/G-protein complexes is a novel aspect of translocation regulation of signalling proteins in sensory cells, and represents a potential link between molecular trafficking and signal transduction in general.
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Affiliation(s)
- Philipp Trojan
- Institut für Zoologie, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
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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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Abstract
Rad23 is required for efficient protein degradation and performs an important role in nucleotide excision repair. Saccharomyces cerevisiae Rad23, and its human counterpart (hHR23), are present in a complex containing the DNA repair factor Rad4 (termed XPC, for xeroderma pigmentosum group C, in humans). XPC/hHR23 was also reported to bind centrin-2, a member of the superfamily of calcium-binding EF-hand proteins. We report here that yeast centrin, which is encoded by CDC31, is similarly present in a complex with Rad4/Rad23 (called NEF2). The interaction between Cdc31 and Rad23/Rad4 varied by growth phase and reflected oscillations in Cdc31 levels. Strikingly, a cdc31 mutant that formed a weaker interaction with Rad4 showed sensitivity to UV light. Based on the dual function of Rad23, in both DNA repair and protein degradation, we questioned if Cdc31 also participated in protein degradation. We report here that Cdc31 binds the proteasome and multiubiquitinated proteins through its carboxy-terminal EF-hand motifs. Moreover, cdc31 mutants were highly sensitive to drugs that cause protein damage, failed to efficiently degrade proteolytic substrates, and formed altered interactions with the proteasome. These findings reveal for the first time a new role for centrin/Cdc31 in protein degradation.
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Zhao Y, Feng J, Liang A, Yang B. Binding of Euplotes octocarinatus centrin with target peptide melittin. CHINESE SCIENCE BULLETIN-CHINESE 2007. [DOI: 10.1007/s11434-007-0476-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Kleylein-Sohn J, Westendorf J, Le Clech M, Habedanck R, Stierhof YD, Nigg EA. Plk4-induced centriole biogenesis in human cells. Dev Cell 2007; 13:190-202. [PMID: 17681131 DOI: 10.1016/j.devcel.2007.07.002] [Citation(s) in RCA: 507] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2007] [Revised: 06/22/2007] [Accepted: 07/03/2007] [Indexed: 01/11/2023]
Abstract
We show that overexpression of Polo-like kinase 4 (Plk4) in human cells induces centrosome amplification through the simultaneous generation of multiple procentrioles adjoining each parental centriole. This provided an opportunity for dissecting centriole assembly and characterizing assembly intermediates. Critical components were identified and ordered into an assembly pathway through siRNA and localized through immunoelectron microscopy. Plk4, hSas-6, CPAP, Cep135, gamma-tubulin, and CP110 were required at different stages of procentriole formation and in association with different centriolar structures. Remarkably, hSas-6 associated only transiently with nascent procentrioles, whereas Cep135 and CPAP formed a core structure within the proximal lumen of both parental and nascent centrioles. Finally, CP110 was recruited early and then associated with the growing distal tips, indicating that centrioles elongate through insertion of alpha-/beta-tubulin underneath a CP110 cap. Collectively, these data afford a comprehensive view of the assembly pathway underlying centriole biogenesis in human cells.
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Affiliation(s)
- Julia Kleylein-Sohn
- Department of Cell Biology, Max-Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
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Selvapandiyan A, Kumar P, Morris JC, Salisbury JL, Wang CC, Nakhasi HL. Centrin1 is required for organelle segregation and cytokinesis in Trypanosoma brucei. Mol Biol Cell 2007; 18:3290-301. [PMID: 17567955 PMCID: PMC1951761 DOI: 10.1091/mbc.e07-01-0022] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Centrin is a calcium-binding centrosome/basal body-associated protein involved in duplication and segregation of these organelles in eukaryotes. We had shown that disruption of one of the centrin genes (centrin1) in Leishmania amastigotes resulted in failure of both basal body duplication and cytokinesis. Here, we undertook to define the role of centrin1 (TbCen1) in the duplication and segregation of basal body and its associated organelles kinetoplast and Golgi, as well as its role in cytokinesis of the procyclic form of Trypanosoma brucei by depleting its protein using RNA inhibition methodology. TbCen1-depleted cells showed significant reduction in growth compared with control cells. Morphological analysis of these cells showed they were large and pleomorphic with multiple detached flagella. Both immunofluorescence assays using organelle-specific antibodies and electron microscopic analysis showed that TbCen1-deficient cells contained multiple basal bodies, kinetoplasts, Golgi, and nuclei. These multiple organelles were, however, closely clustered together, indicating duplication without segregation in the absence of centrin. This failure in organelle segregation may be the likely cause of inhibition of cytokinesis, suggesting for the first time a new and unique role for centrin in the segregation of organelles without affecting their multiplication in the procyclic form of T. brucei.
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Affiliation(s)
- Angamuthu Selvapandiyan
- *Division of Emerging and Transfusion Transmitted Diseases, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892
| | - Praveen Kumar
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94143
| | - James C. Morris
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634; and
| | | | - Ching C. Wang
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94143
| | - Hira L. Nakhasi
- *Division of Emerging and Transfusion Transmitted Diseases, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892
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