1
|
Prassanawar SS, Sarkar T, Panda D. CEP41, a ciliopathy-linked centrosomal protein, regulates microtubule assembly and cell proliferation. J Cell Sci 2024; 137:jcs261927. [PMID: 38841887 DOI: 10.1242/jcs.261927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Accepted: 05/29/2024] [Indexed: 06/07/2024] Open
Abstract
Centrosomal proteins play pivotal roles in orchestrating microtubule dynamics, and their dysregulation leads to disorders, including cancer and ciliopathies. Understanding the multifaceted roles of centrosomal proteins is vital to comprehend their involvement in disease development. Here, we report novel cellular functions of CEP41, a centrosomal and ciliary protein implicated in Joubert syndrome. We show that CEP41 is an essential microtubule-associated protein with microtubule-stabilizing activity. Purified CEP41 binds to preformed microtubules, promotes microtubule nucleation and suppresses microtubule disassembly. When overexpressed in cultured cells, CEP41 localizes to microtubules and promotes microtubule bundling. Conversely, shRNA-mediated knockdown of CEP41 disrupts the interphase microtubule network and delays microtubule reassembly, emphasizing its role in microtubule organization. Further, we demonstrate that the association of CEP41 with microtubules relies on its conserved rhodanese homology domain (RHOD) and the N-terminal region. Interestingly, a disease-causing mutation in the RHOD domain impairs CEP41-microtubule interaction. Moreover, depletion of CEP41 inhibits cell proliferation and disrupts cell cycle progression, suggesting its potential involvement in cell cycle regulation. These insights into the cellular functions of CEP41 hold promise for unraveling the impact of its mutations in ciliopathies.
Collapse
Affiliation(s)
- Shweta Shyam Prassanawar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Tuhin Sarkar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Dulal Panda
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
- National Institute of Pharmaceutical Education and Research, SAS Nagar, Punjab 160062, India
| |
Collapse
|
2
|
Glover HL, Mendes M, Gomes-Neto J, Rusilowicz-Jones EV, Rigden DJ, Dittmar G, Urbé S, Clague MJ. Microtubule association of TRIM3 revealed by differential extraction proteomics. J Cell Sci 2024; 137:jcs261522. [PMID: 38149663 PMCID: PMC10917062 DOI: 10.1242/jcs.261522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 12/15/2023] [Indexed: 12/28/2023] Open
Abstract
The microtubule network is formed from polymerised tubulin subunits and associating proteins, which govern microtubule dynamics and a diverse array of functions. To identify novel microtubule-binding proteins, we have developed an unbiased biochemical assay, which relies on the selective extraction of cytosolic proteins from U2OS cells, while leaving behind the microtubule network. Candidate proteins are linked to microtubules by their sensitivities to the depolymerising drug nocodazole or the microtubule-stabilising drug taxol, which is quantitated by mass spectrometry. Our approach is benchmarked by co-segregation of tubulin and previously established microtubule-binding proteins. We then identify several novel candidate microtubule-binding proteins, from which we have selected the ubiquitin E3 ligase tripartite motif-containing protein 3 (TRIM3) for further characterisation. We map TRIM3 microtubule binding to its C-terminal NHL-repeat region. We show that TRIM3 is required for the accumulation of acetylated tubulin, following treatment with taxol. Furthermore, loss of TRIM3 partially recapitulates the reduction in nocodazole-resistant microtubules characteristic of α-tubulin acetyltransferase 1 (ATAT1) depletion. These results can be explained by a decrease in ATAT1 following depletion of TRIM3 that is independent of transcription.
Collapse
Affiliation(s)
- Hannah L. Glover
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool L69 3BX, UK
| | - Marta Mendes
- Proteomics of Cellular Signalling, Department of Infection and Immunity,Luxembourg Institute of Health, L-1445 Strassen, Luxembourg
| | - Joana Gomes-Neto
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool L69 3BX, UK
| | - Emma V. Rusilowicz-Jones
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool L69 3BX, UK
| | - Daniel J. Rigden
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool L69 3BX, UK
| | - Gunnar Dittmar
- Proteomics of Cellular Signalling, Department of Infection and Immunity,Luxembourg Institute of Health, L-1445 Strassen, Luxembourg
- Department of Life Sciences and Medicine, University of Luxembourg, 2 Avenue de l'Université, Campus Belval, L-4365 Esch-sur-Alzette, Luxembourg
| | - Sylvie Urbé
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool L69 3BX, UK
| | - Michael J. Clague
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool L69 3BX, UK
| |
Collapse
|
3
|
Cevik S, Kaplan OI. The Joubert syndrome protein CEP41 is excluded from the distal segment of cilia in C. elegans. MICROPUBLICATION BIOLOGY 2021; 2021:10.17912/micropub.biology.000406. [PMID: 34113804 PMCID: PMC8185565 DOI: 10.17912/micropub.biology.000406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 05/21/2021] [Accepted: 06/02/2021] [Indexed: 11/16/2022]
Abstract
Rare diseases are a fundamental issue in today's world, affecting more than 300 million individuals worldwide. According to data from Orphanet and OMIM, about 50-60 new conditions are added to the list of over 6,000 clinically distinct diseases each year, rendering disease diagnosis and treatment even more challenging. Ciliopathies comprise a heterogeneous category of rare diseases made up of over 35 distinct diseases, including Joubert syndrome (JBTS; OMIM 213300), that are caused by functional and structural defects in cilia. JBTS is an autosomal recessive condition characterized by a range of symptoms, including cerebellar vermis hypoplasia and poor muscle tone. There are now a total of 38 genes that cause JBTS, almost all of which encode protein products that are found in cilia and cilia-associated compartments, such as the basal body and transition zone. CEP41 is a JBTS-associated protein that is found in cilia and the basal body of mammals, but its localization in other ciliary organisms remains elusive. C. elegans is an excellent model organism for studying the molecular mechanisms of rare diseases like JBTS. We, therefore, decided to use C. elegans to identify the localization of CEP41. Our microscopy analysis revealed that CEPH-41(CEntrosomal Protein Homolog 41) not only localizes to cilia but is excluded from the distal segment of the amphid and phasmid cilia in C. elegans. Furthermore, we discovered a putative X-box motif located in the promoter of ceph-41 and the expression of ceph-41 is regulated by DAF-19, a sole Regulatory Factor X (RFX) transcription factor.
Collapse
Affiliation(s)
- Sebiha Cevik
- Rare Disease Laboratory, School of Life and Natural Sciences, Abdullah Gul University, Kayseri, Turkey
| | - Oktay I. Kaplan
- Rare Disease Laboratory, School of Life and Natural Sciences, Abdullah Gul University, Kayseri, Turkey
| |
Collapse
|
4
|
Yin H, Zhang T, Wang H, Hu X, Hou X, Fang X, Yin Y, Li H, Shi L, Su YQ. Echinoderm Microtubule Associated Protein Like 1 Is Indispensable for Oocyte Spindle Assembly and Meiotic Progression in Mice. Front Cell Dev Biol 2021; 9:687522. [PMID: 34124073 PMCID: PMC8194061 DOI: 10.3389/fcell.2021.687522] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 05/04/2021] [Indexed: 12/02/2022] Open
Abstract
Completion of the first meiosis is an essential prerequisite for producing a functionally normal egg for fertilization and embryogenesis, but the precise mechanisms governing oocyte meiotic progression remains largely unclear. Here, we report that echinoderm microtubule associated protein (EMAP) like 1 (EML1), a member of the conserved EMAP family proteins, plays a crucial role in the control of oocyte meiotic progression in the mouse. Female mice carrying an ENU-induced nonsense mutation (c.1956T > A; p.Tyr652∗) of Eml1 are infertile, and the majority of their ovulated oocytes contain abnormal spindles and misaligned chromosomes. In accordance with the mutant oocyte phenotype, we find that EML1 is colocalized with spindle microtubules during the process of normal oocyte meiotic maturation, and knockdown (KD) of EML1 by specific morpholinos in the fully grown oocytes (FGOs) disrupts the integrity of spindles, and delays meiotic progression. Moreover, EML1-KD oocytes fail to progress to metaphase II (MII) stage after extrusion of the first polar body, but enter into interphase and form a pronucleus containing decondensed chromatins. Further analysis shows that EML1-KD impairs the recruitment of γ-tubulin and pericentrin to the spindle poles, as well as the attachment of kinetochores to microtubules and the proper inactivation of spindle assembly checkpoint at metaphase I (MI). The loss of EML1 also compromises the activation of maturation promoting factor around the time of oocyte resumption and completion of the first meiosis, which, when corrected by WEE1/2 inhibitor PD166285, efficiently rescues the phenotype of oocyte delay of meiotic resumption and inability of reaching MII. Through IP- mass spectrometry analysis, we identified that EML1 interacts with nuclear distribution gene C (NUDC), a critical mitotic regulator in somatic cells, and EML1-KD disrupts the specific localization of NUDC at oocyte spindles. Taken together, these data suggest that EML1 regulates acentrosomal spindle formation and the progression of meiosis to MII in mammalian oocytes, which is likely mediated by distinct mechanisms.
Collapse
Affiliation(s)
- Hong Yin
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China
| | - Teng Zhang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China
| | - Hao Wang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China
| | - Xin Hu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China
| | - Xuan Hou
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China
| | - Xianbao Fang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China
| | - Yaoxue Yin
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China
| | - Hui Li
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Lanying Shi
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - You-Qiang Su
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
- Women’s Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Hospital, Nanjing Medical University, Nanjing, China
- Collaborative Innovation Center of Genetics and Development, Fudan University, Shanghai, China
| |
Collapse
|
5
|
Oocyte competence is maintained by m 6A methyltransferase KIAA1429-mediated RNA metabolism during mouse follicular development. Cell Death Differ 2020; 27:2468-2483. [PMID: 32094512 DOI: 10.1038/s41418-020-0516-1] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Revised: 02/05/2020] [Accepted: 02/07/2020] [Indexed: 12/19/2022] Open
Abstract
KIAA1429 (also known as vir-like m6A methyltransferase-associated protein (VIRMA)), a newly identified component of the RNA m6A methyltransferase complex, plays critical roles in guiding region-selective m6A deposition. However, in mammals, whether KIAA1429 mediates RNA m6A regulatory pathway functions in vivo remains unknown. Here, we show that the Kiaa1429-specific deficiency in oocytes resulted in female infertility with defective follicular development and fully grown germinal vesicle (GV) oocytes failing to undergo germinal vesicle breakdown (GVBD) and consequently losing the ability to resume meiosis. The oocyte growth is accompanied by the accumulation of abundant RNAs and posttranscriptional regulation. We found that the loss of Kiaa1429 could also lead to abnormal RNA metabolism in GV oocytes. RNA-seq profiling revealed that Kiaa1429 deletion altered the expression pattern of the oocyte-derived factors essential for follicular development. In addition, our data show that the conditional depletion of Kiaa1429 decreased the m6A levels in oocytes and mainly affected the alternative splicing of genes associated with oogenesis. In summary, the m6A methyltransferase KIAA1429-mediated RNA metabolism plays critical roles in folliculogenesis and the maintenance of oocyte competence.
Collapse
|
6
|
Bompard G, van Dijk J, Cau J, Lannay Y, Marcellin G, Lawera A, van der Laan S, Rogowski K. CSAP Acts as a Regulator of TTLL-Mediated Microtubule Glutamylation. Cell Rep 2019; 25:2866-2877.e5. [PMID: 30517872 DOI: 10.1016/j.celrep.2018.10.095] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 12/22/2017] [Accepted: 10/25/2018] [Indexed: 01/22/2023] Open
Abstract
Tubulin glutamylation is a reversible posttranslational modification that accumulates on stable microtubules (MTs). While abnormally high levels of this modification lead to a number of disorders such as male sterility, retinal degeneration, and neurodegeneration, very little is known about the molecular mechanisms underlying the regulation of glutamylase activity. Here, we found that CSAP forms a complex with TTLL5, and we demonstrate that the two proteins regulate their reciprocal abundance. Moreover, we show that CSAP increases TTLL5-mediated glutamylation and identify the TTLL5-interacting domain. Deletion of this domain leads to complete loss of CSAP activating function without impacting its MT binding. Binding of CSAP to TTLL5 promotes relocalization of TTLL5 toward MTs. Finally, we show that CSAP binds and activates all of the remaining autonomously active TTLL glutamylases. As such, we present CSAP as a major regulator of tubulin glutamylation and associated functions.
Collapse
Affiliation(s)
- Guillaume Bompard
- Institute of Human Genetics (IGH), UMR9002 CNRS-University of Montpellier, 34094 Cedex 5, 141 Rue de la Cardonille, 34090 Montpellier, France
| | - Juliette van Dijk
- Institute of Human Genetics (IGH), UMR9002 CNRS-University of Montpellier, 34094 Cedex 5, 141 Rue de la Cardonille, 34090 Montpellier, France
| | - Julien Cau
- Institute of Human Genetics (IGH), UMR9002 CNRS-University of Montpellier, 34094 Cedex 5, 141 Rue de la Cardonille, 34090 Montpellier, France
| | - Yoann Lannay
- Institute of Human Genetics (IGH), UMR9002 CNRS-University of Montpellier, 34094 Cedex 5, 141 Rue de la Cardonille, 34090 Montpellier, France
| | - Guillaume Marcellin
- Institute of Human Genetics (IGH), UMR9002 CNRS-University of Montpellier, 34094 Cedex 5, 141 Rue de la Cardonille, 34090 Montpellier, France
| | - Aleksandra Lawera
- Institute of Human Genetics (IGH), UMR9002 CNRS-University of Montpellier, 34094 Cedex 5, 141 Rue de la Cardonille, 34090 Montpellier, France
| | - Siem van der Laan
- Institute of Human Genetics (IGH), UMR9002 CNRS-University of Montpellier, 34094 Cedex 5, 141 Rue de la Cardonille, 34090 Montpellier, France
| | - Krzysztof Rogowski
- Institute of Human Genetics (IGH), UMR9002 CNRS-University of Montpellier, 34094 Cedex 5, 141 Rue de la Cardonille, 34090 Montpellier, France.
| |
Collapse
|
7
|
Bodakuntla S, Jijumon AS, Villablanca C, Gonzalez-Billault C, Janke C. Microtubule-Associated Proteins: Structuring the Cytoskeleton. Trends Cell Biol 2019; 29:804-819. [PMID: 31416684 DOI: 10.1016/j.tcb.2019.07.004] [Citation(s) in RCA: 169] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 07/11/2019] [Accepted: 07/12/2019] [Indexed: 11/27/2022]
Abstract
Microtubule-associated proteins (MAPs) were initially discovered as proteins that bind to and stabilize microtubules. Today, an ever-growing number of MAPs reveals a more complex picture of these proteins as organizers of the microtubule cytoskeleton that have a large variety of functions. MAPs enable microtubules to participate in a plethora of cellular processes such as the assembly of mitotic and meiotic spindles, neuronal development, and the formation of the ciliary axoneme. Although some subgroups of MAPs have been exhaustively characterized, a strikingly large number of MAPs remain barely characterized other than their interactions with microtubules. We provide a comprehensive view on the currently known MAPs in mammals. We discuss their molecular mechanisms and functions, as well as their physiological role and links to pathologies.
Collapse
Affiliation(s)
- Satish Bodakuntla
- Institut Curie, Paris Sciences et Lettres (PSL) Research University, Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche (UMR) 3348, F-91405 Orsay, France; Université Paris Sud, Université Paris-Saclay, CNRS UMR 3348, F-91405 Orsay, France
| | - A S Jijumon
- Institut Curie, Paris Sciences et Lettres (PSL) Research University, Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche (UMR) 3348, F-91405 Orsay, France; Université Paris Sud, Université Paris-Saclay, CNRS UMR 3348, F-91405 Orsay, France
| | - Cristopher Villablanca
- Center for Geroscience, Brain Health, and Metabolism (GERO), Santiago, Chile; Department of Biology, Faculty of Sciences, University of Chile, Santiago, Chile
| | - Christian Gonzalez-Billault
- Center for Geroscience, Brain Health, and Metabolism (GERO), Santiago, Chile; Department of Biology, Faculty of Sciences, University of Chile, Santiago, Chile.
| | - Carsten Janke
- Institut Curie, Paris Sciences et Lettres (PSL) Research University, Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche (UMR) 3348, F-91405 Orsay, France; Université Paris Sud, Université Paris-Saclay, CNRS UMR 3348, F-91405 Orsay, France.
| |
Collapse
|
8
|
Patowary A, Won SY, Oh SJ, Nesbitt RR, Archer M, Nickerson D, Raskind WH, Bernier R, Lee JE, Brkanac Z. Family-based exome sequencing and case-control analysis implicate CEP41 as an ASD gene. Transl Psychiatry 2019; 9:4. [PMID: 30664616 PMCID: PMC6341097 DOI: 10.1038/s41398-018-0343-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 11/13/2018] [Indexed: 12/03/2022] Open
Abstract
Autism Spectrum Disorder (ASD) is a complex neurodevelopmental disorder with a strong genetic component. Although next-generation sequencing (NGS) technologies have been successfully applied to gene identification in de novo ASD, the genetic architecture of familial ASD remains largely unexplored. Our approach, which leverages the high specificity and sensitivity of NGS technology, has focused on rare variants in familial autism. We used NGS exome sequencing in 26 families with distantly related affected individuals to identify genes with private gene disrupting and missense variants of interest (VOI). We found that the genes carrying VOIs were enriched for biological processes related to cell projection organization and neuron development, which is consistent with the neurodevelopmental hypothesis of ASD. For a subset of genes carrying VOIs, we then used targeted NGS sequencing and gene-based variant burden case-control analysis to test for association with ASD. Missense variants in one gene, CEP41, associated significantly with ASD (p = 6.185e-05). Homozygous gene-disrupting variants in CEP41 were initially found to be responsible for recessive Joubert syndrome. Using a zebrafish model, we evaluated the mechanism by which the CEP41 variants might contribute to ASD. We found that CEP41 missense variants affect development of the axonal tract, cranial neural crest migration and social behavior phenotype. Our work demonstrates the involvement of CEP41 heterozygous missense variants in ASD and that biological processes involved in cell projection organization and neuron development are enriched in ASD families we have studied.
Collapse
Affiliation(s)
- Ashok Patowary
- 0000000122986657grid.34477.33Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA USA
| | - So Yeon Won
- 0000 0001 2181 989Xgrid.264381.aDepartment of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Korea
| | - Shin Ji Oh
- 0000 0001 2181 989Xgrid.264381.aDepartment of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Korea
| | - Ryan R Nesbitt
- 0000000122986657grid.34477.33Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA USA
| | - Marilyn Archer
- 0000000122986657grid.34477.33Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA USA
| | - Debbie Nickerson
- 0000000122986657grid.34477.33Department of Genome Sciences, University of Washington, Seattle, WA USA
| | - Wendy H. Raskind
- 0000000122986657grid.34477.33Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA USA ,0000000122986657grid.34477.33Department of Medicine, Division of Medical Genetics, University of Washington, Seattle, WA USA
| | - Raphael Bernier
- 0000000122986657grid.34477.33Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA USA
| | - Ji Eun Lee
- Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Korea. .,Division of Medical Science Research, Samsung Medical Center, Seoul, Korea.
| | - Zoran Brkanac
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA.
| |
Collapse
|
9
|
Rosas-Salvans M, Cavazza T, Espadas G, Sabido E, Vernos I. Proteomic Profiling of Microtubule Self-organization in M-phase. Mol Cell Proteomics 2018; 17:1991-2004. [PMID: 29970457 DOI: 10.1074/mcp.ra118.000745] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 06/11/2018] [Indexed: 01/08/2023] Open
Abstract
Microtubules (MTs) and associated proteins can self-organize into complex structures such as the bipolar spindle, a process in which RanGTP plays a major role. Addition of RanGTP to M-phase Xenopus egg extracts promotes the nucleation and self-organization of MTs into asters and bipolar-like structures in the absence of centrosomes or chromosomes. We show here that the complex proteome of these RanGTP-induced MT assemblies is similar to that of mitotic spindles. Using proteomic profiling we show that MT self-organization in the M-phase cytoplasm involves the non-linear and non-stoichiometric recruitment of proteins from specific functional groups. Our study provides for the first time a temporal understanding of the protein dynamics driving MT self-organization in M-phase.
Collapse
Affiliation(s)
- Miquel Rosas-Salvans
- From the ‡Cell and Developmental Biology Programme, Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain
| | - Tommaso Cavazza
- From the ‡Cell and Developmental Biology Programme, Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain
| | - Guadalupe Espadas
- **Proteomics Unit, Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain.,§Universitat Pompeu Fabra, Dr. Aiguader 88, 08003 Barcelona, Spain
| | - Eduard Sabido
- **Proteomics Unit, Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain.,§Universitat Pompeu Fabra, Dr. Aiguader 88, 08003 Barcelona, Spain
| | - Isabelle Vernos
- From the ‡Cell and Developmental Biology Programme, Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain; .,§Universitat Pompeu Fabra, Dr. Aiguader 88, 08003 Barcelona, Spain.,‡‡Institució Catalana de Recerca I Estudis Avançats (ICREA), Passeig de Lluis Companys 23, 08010 Barcelona, Spain
| |
Collapse
|
10
|
Chudinova EM, Nadezhdina ES. Interactions between the Translation Machinery and Microtubules. BIOCHEMISTRY (MOSCOW) 2018; 83:S176-S189. [PMID: 29544439 DOI: 10.1134/s0006297918140146] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Microtubules are components of eukaryotic cytoskeleton that are involved in the transport of various components from the nucleus to the cell periphery and back. They also act as a platform for assembly of complex molecular ensembles. Ribonucleoprotein (RNP) complexes, such as ribosomes and mRNPs, are transported over significant distances (e.g. to neuronal processes) along microtubules. The association of RNPs with microtubules and their transport along these structures are essential for compartmentalization of protein biosynthesis in cells. Microtubules greatly facilitate assembly of stress RNP granules formed by accumulation of translation machinery components during cell stress response. Microtubules are necessary for the cytoplasm-to-nucleus transport of proteins, including ribosomal proteins. At the same time, ribosomal proteins and RNA-binding proteins can influence cell mobility and cytoplasm organization by regulating microtubule dynamics. The molecular mechanisms underlying the association between the translation machinery components and microtubules have not been studied systematically; the results of such studies are mostly fragmentary. In this review, we attempt to fill this gap by summarizing and discussing the data on protein and RNA components of the translation machinery that directly interact with microtubules or microtubule motor proteins.
Collapse
Affiliation(s)
- E M Chudinova
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia.
| | | |
Collapse
|
11
|
Gupta M, Sonnett M, Ryazanova L, Presler M, Wühr M. Quantitative Proteomics of Xenopus Embryos I, Sample Preparation. Methods Mol Biol 2018; 1865:175-194. [PMID: 30151767 DOI: 10.1007/978-1-4939-8784-9_13] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Xenopus oocytes and embryos are model systems optimally suited for quantitative proteomics. This is due to the availability of large amount of protein material and the ease of physical manipulation. Furthermore, facile in vitro fertilization provides superbly synchronized embryos for cell cycle and developmental stages. Here, we detail protocols developed over the last few years for sample preparation of multiplexed proteomics with TMT-tags followed by quantitative mass spectrometry analysis using the MultiNotch MS3 approach. In this approach, each condition is barcoded with an isobaric tag at the peptide level. After barcoding, samples are combined and the relative abundance of ~100,000 peptides is quantified on a mass spectrometer. High reproducibility of the sample preparation process prior to peptides being tagged and combined is of upmost importance for obtaining unbiased data. Otherwise, differences in sample handling can inadvertently appear as biological changes. We detail and exemplify the application of our sample workflow on an embryonic time-series of ten developmental stages of Xenopus laevis embryos ranging from the egg to stage 35 (just before hatching). Our accompanying paper (Chapter 14 ) details a bioinformatics pipeline to analyze the quality of the given sample preparation and strategies to convert spectra of X. laevis peptides into biologically interpretable data.
Collapse
Affiliation(s)
- Meera Gupta
- Department of Molecular Biology and Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA.,Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, USA
| | - Matthew Sonnett
- Department of Molecular Biology and Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
| | - Lillia Ryazanova
- Department of Molecular Biology and Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
| | - Marc Presler
- Department of Systems Biology, Harvard Medical School, Boston, MA, USA
| | - Martin Wühr
- Department of Molecular Biology and Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA.
| |
Collapse
|
12
|
Derbyshire P, Ménard D, Green P, Saalbach G, Buschmann H, Lloyd CW, Pesquet E. Proteomic Analysis of Microtubule Interacting Proteins over the Course of Xylem Tracheary Element Formation in Arabidopsis. THE PLANT CELL 2015; 27:2709-26. [PMID: 26432860 PMCID: PMC4682315 DOI: 10.1105/tpc.15.00314] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 09/15/2015] [Indexed: 05/07/2023]
Abstract
Plant vascular cells, or tracheary elements (TEs), rely on circumferential secondary cell wall thickenings to maintain sap flow. The patterns in which TE thickenings are organized vary according to the underlying microtubule bundles that guide wall deposition. To identify microtubule interacting proteins present at defined stages of TE differentiation, we exploited the synchronous differentiation of TEs in Arabidopsis thaliana suspension cultures. Quantitative proteomic analysis of microtubule pull-downs, using ratiometric (14)N/(15)N labeling, revealed 605 proteins exhibiting differential accumulation during TE differentiation. Microtubule interacting proteins associated with membrane trafficking, protein synthesis, DNA/RNA binding, and signal transduction peaked during secondary cell wall formation, while proteins associated with stress peaked when approaching TE cell death. In particular, CELLULOSE SYNTHASE-INTERACTING PROTEIN1, already associated with primary wall synthesis, was enriched during secondary cell wall formation. RNAi knockdown of genes encoding several of the identified proteins showed that secondary wall formation depends on the coordinated presence of microtubule interacting proteins with nonoverlapping functions: cell wall thickness, cell wall homogeneity, and the pattern and cortical location of the wall are dependent on different proteins. Altogether, proteins linking microtubules to a range of metabolic compartments vary specifically during TE differentiation and regulate different aspects of wall patterning.
Collapse
Affiliation(s)
- Paul Derbyshire
- John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom
| | - Delphine Ménard
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, 901 87 Umeå, Sweden
| | - Porntip Green
- John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom
| | - Gerhard Saalbach
- John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom
| | - Henrik Buschmann
- John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom
| | - Clive W Lloyd
- John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom
| | - Edouard Pesquet
- John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, 901 87 Umeå, Sweden
| |
Collapse
|
13
|
Laflamme G, Tremblay-Boudreault T, Roy MA, Andersen P, Bonneil É, Atchia K, Thibault P, D'Amours D, Kwok BH. Structural maintenance of chromosome (SMC) proteins link microtubule stability to genome integrity. J Biol Chem 2014; 289:27418-31. [PMID: 25135640 DOI: 10.1074/jbc.m114.569608] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Structural maintenance of chromosome (SMC) proteins are key organizers of chromosome architecture and are essential for genome integrity. They act by binding to chromatin and connecting distinct parts of chromosomes together. Interestingly, their potential role in providing connections between chromatin and the mitotic spindle has not been explored. Here, we show that yeast SMC proteins bind directly to microtubules and can provide a functional link between microtubules and DNA. We mapped the microtubule-binding region of Smc5 and generated a mutant with impaired microtubule binding activity. This mutant is viable in yeast but exhibited a cold-specific conditional lethality associated with mitotic arrest, aberrant spindle structures, and chromosome segregation defects. In an in vitro reconstitution assay, this Smc5 mutant also showed a compromised ability to protect microtubules from cold-induced depolymerization. Collectively, these findings demonstrate that SMC proteins can bind to and stabilize microtubules and that SMC-microtubule interactions are essential to establish a robust system to maintain genome integrity.
Collapse
Affiliation(s)
- Guillaume Laflamme
- From the Chemical Biology of Cell Division Laboratory, the Laboratory of Cell Cycle Regulation and Chromosome Structure, and
| | | | - Marc-André Roy
- the Laboratory of Cell Cycle Regulation and Chromosome Structure, and
| | | | - Éric Bonneil
- the Laboratory of Proteomics and Bioanalytical Mass Spectrometry, Institute for Research in Immunology and Cancer, and
| | - Kaleem Atchia
- From the Chemical Biology of Cell Division Laboratory
| | - Pierre Thibault
- the Laboratory of Proteomics and Bioanalytical Mass Spectrometry, Institute for Research in Immunology and Cancer, and the Departments of Chemistry
| | - Damien D'Amours
- the Laboratory of Cell Cycle Regulation and Chromosome Structure, and Pathology and Cellular Biology, and
| | - Benjamin H Kwok
- From the Chemical Biology of Cell Division Laboratory, Medicine, Université de Montréal, Station Centre-Ville, Montréal, Québec H3C 3J7, Canada
| |
Collapse
|
14
|
Schou KB, Andersen JS, Pedersen LB. A divergent calponin homology (NN-CH) domain defines a novel family: implications for evolution of ciliary IFT complex B proteins. Bioinformatics 2014; 30:899-902. [PMID: 24257188 DOI: 10.1093/bioinformatics/btt661] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023] Open
Abstract
MOTIVATION Microtubules are dynamic polymers of tubulin dimers that undergo continuous assembly and disassembly. A mounting number of microtubule-associated proteins (MAPs) regulate the dynamic behavior of microtubules and hence the assembly and disassembly of disparate microtubule structures within the cell. Despite recent advances in identification and functional characterization of MAPs, a substantial number of microtubule accessory factors have not been functionally annotated. Here, using profile-to-profile comparisons and structure modeling, we show that the yeast outer kinetochore components NDC80 and NUF2 share evolutionary ancestry with a novel protein family in mammals comprising, besides NDC80/HEC1 and NUF2, three Intraflagellar Transport (IFT) complex B subunits (IFT81, IFT57, CLUAP1) as well as six proteins with poorly defined function (FAM98A-C, CCDC22, CCDC93 and C14orf166). We show that these proteins consist of a divergent N-terminal calponin homology (CH)-like domain adjoined to an array of C-terminal heptad repeats predicted to form a coiled-coil arrangement. We have named the divergent CH-like domain NN-CH after the founding members NDC80 and NUF2.
Collapse
Affiliation(s)
- Kenneth B Schou
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark and Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen OE, Denmark
| | | | | |
Collapse
|
15
|
Jiang H, He X, Wang S, Jia J, Wan Y, Wang Y, Zeng R, Yates J, Zhu X, Zheng Y. A microtubule-associated zinc finger protein, BuGZ, regulates mitotic chromosome alignment by ensuring Bub3 stability and kinetochore targeting. Dev Cell 2014; 28:268-81. [PMID: 24462186 DOI: 10.1016/j.devcel.2013.12.013] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 12/09/2013] [Accepted: 12/20/2013] [Indexed: 11/28/2022]
Abstract
Equal chromosome segregation requires proper assembly of many proteins, including Bub3, onto kinetochores to promote kinetochore-microtubule interactions. By screening for mitotic regulators in the spindle envelope and matrix (Spemix), we identify a conserved Bub3 interacting and GLE-2-binding sequence (GLEBS) containing ZNF207 (BuGZ) that associates with spindle microtubules and regulates chromosome alignment. Using its conserved GLEBS, BuGZ directly binds and stabilizes Bub3. BuGZ also uses its microtubule-binding domain to enhance the loading of Bub3 to kinetochores that have assumed initial interactions with microtubules in prometaphase. This enhanced Bub3 loading is required for proper chromosome alignment and metaphase to anaphase progression. Interestingly, we show that microtubules are required for the highest kinetochore loading of Bub3, BubR1, and CENP-E during prometaphase. These findings suggest that BuGZ not only serves as a molecular chaperone for Bub3 but also enhances its loading onto kinetochores during prometaphase in a microtubule-dependent manner to promote chromosome alignment.
Collapse
Affiliation(s)
- Hao Jiang
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China; Department of Embryology, Carnegie Institution for Science, 3520 San Martin Dr., Baltimore, MD 21218, USA
| | - Xiaonan He
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Shusheng Wang
- Department of Embryology, Carnegie Institution for Science, 3520 San Martin Dr., Baltimore, MD 21218, USA
| | - Junling Jia
- Department of Embryology, Carnegie Institution for Science, 3520 San Martin Dr., Baltimore, MD 21218, USA
| | - Yihan Wan
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China; Department of Embryology, Carnegie Institution for Science, 3520 San Martin Dr., Baltimore, MD 21218, USA
| | - Yueju Wang
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Rong Zeng
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - John Yates
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Xueliang Zhu
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
| | - Yixian Zheng
- Department of Embryology, Carnegie Institution for Science, 3520 San Martin Dr., Baltimore, MD 21218, USA.
| |
Collapse
|
16
|
Abstract
Rather than providing a single specific protocol, the inclusive area of seed proteomics is reviewed; methods are described and compared and primary literature citations are provided. The limitations and challenges of proteomics as an approach to study seed biology are emphasized. The proteomic analysis of seeds encounters some specific problems that do not impinge on analyses of other plant cells, tissues, or organs. There are anatomic considerations. Seeds comprise the seed coat, the storage organ(s), and the embryonic axis. Are these to be studied individually or as a composite? The physiological status of the seeds must be considered; developing, mature, or germinating? If mature, are they quiescent or dormant? If mature and quiescent, then orthodox or recalcitrant? The genetic uniformity of the population of seeds being compared must be considered. Finally, seeds are protein-rich and the extreme abundance of the storage proteins results in a study-subject with a dynamic range that spans several orders of magnitude. This represents a problem that must be dealt with if the study involves analysis of proteins that are of "normal" to low abundance. Several different methods of prefractionation are described and the results compared.
Collapse
Affiliation(s)
- Ján A Miernyk
- USDA, Agricultural Research Service, Plant Genetics Research Unit, Department of Biochemistry, Interdisciplinary Plant Group, University of Missouri, Columbia, MO, USA
| |
Collapse
|
17
|
Hamada T, Nagasaki-Takeuchi N, Kato T, Fujiwara M, Sonobe S, Fukao Y, Hashimoto T. Purification and characterization of novel microtubule-associated proteins from Arabidopsis cell suspension cultures. PLANT PHYSIOLOGY 2013; 163:1804-16. [PMID: 24134884 PMCID: PMC3850192 DOI: 10.1104/pp.113.225607] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Plant microtubules (MTs) play essential roles in cell division, anisotropic cell expansion, and overall organ morphology. Microtubule-associated proteins (MAPs) bind to MTs and regulate their dynamics, stability, and organization. Identifying the full set of MAPs in plants would greatly enhance our understanding of how diverse MT arrays are formed and function; however, few proteomics studies have characterized plant MAPs. Using liquid chromatography-tandem mass spectrometry, we identified hundreds of proteins from MAP-enriched preparations derived from cell suspension cultures of Arabidopsis (Arabidopsis thaliana). Previously reported MAPs, MT regulators, kinesins, dynamins, peroxisome-resident enzymes, and proteins implicated in replication, transcription, and translation were highly enriched. Dozens of proteins of unknown function were identified, among which 12 were tagged with green fluorescent protein (GFP) and examined for their ability to colocalize with MTs when transiently expressed in plant cells. Six proteins did indeed colocalize with cortical MTs in planta. We further characterized one of these MAPs, designated as BASIC PROLINE-RICH PROTEIN1 (BPP1), which belongs to a seven-member family in Arabidopsis. BPP1-GFP decorated interphase and mitotic MT arrays in transgenic Arabidopsis plants. A highly basic, conserved region was responsible for the in vivo MT association. Overexpression of BPP1-GFP stabilized MTs, caused right-handed helical growth in rapidly elongating tissues, promoted the formation of transverse MT arrays, and resulted in the outgrowth of epidermal cells in light-grown hypocotyls. Our high-quality proteome database of Arabidopsis MAP-enriched preparations is a useful resource for identifying novel MT regulators and evaluating potential MT associations of proteins known to have other cellular functions.
Collapse
|
18
|
Syred HM, Welburn J, Rappsilber J, Ohkura H. Cell cycle regulation of microtubule interactomes: multi-layered regulation is critical for the interphase/mitosis transition. Mol Cell Proteomics 2013; 12:3135-47. [PMID: 23893837 PMCID: PMC3820929 DOI: 10.1074/mcp.m113.028563] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Revised: 07/25/2013] [Indexed: 12/17/2022] Open
Abstract
Microtubules dramatically change their dynamics and organization at the entry into mitosis. Although this change is mediated by microtubule-associated proteins (MAPs), how MAPs themselves are regulated is not well understood. Here we used an integrated multi-level approach to establish the framework and biological significance of MAP regulation critical for the interphase/mitosis transition. Firstly, we applied quantitative proteomics to determine global cell cycle changes in the profiles of MAPs in human and Drosophila cells. This uncovered a wide range of cell cycle regulations of MAPs previously unidentified. Secondly, systematic studies of human kinesins highlighted an overlooked aspect of kinesins: most mitotic kinesins suppress their affinity to microtubules or reduce their protein levels in interphase in combination with nuclear localization. Thirdly, in-depth analysis of a novel Drosophila MAP (Mink) revealed that the suppression of the microtubule affinity of this mitotic MAP in combination with nuclear localization is essential for microtubule organization in interphase, and phosphorylation of Mink is needed for kinetochore-microtubule attachment in mitosis. Thus, this first comprehensive analysis of MAP regulation for the interphase/mitosis transition advances our understanding of kinesin biology and reveals the prevalence and importance of multi-layered MAP regulation.
Collapse
Affiliation(s)
- Heather M. Syred
- From the ‡Wellcome Trust Centre for Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3JR, United Kingdom
| | - Julie Welburn
- From the ‡Wellcome Trust Centre for Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3JR, United Kingdom
| | - Juri Rappsilber
- From the ‡Wellcome Trust Centre for Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3JR, United Kingdom
| | - Hiroyuki Ohkura
- From the ‡Wellcome Trust Centre for Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3JR, United Kingdom
| |
Collapse
|
19
|
Castañón MJ, Walko G, Winter L, Wiche G. Plectin-intermediate filament partnership in skin, skeletal muscle, and peripheral nerve. Histochem Cell Biol 2013; 140:33-53. [PMID: 23748243 PMCID: PMC3695321 DOI: 10.1007/s00418-013-1102-0] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/23/2013] [Indexed: 01/13/2023]
Abstract
Plectin is a large, 500-kDa, intermediate filament (IF)-associated protein. It acts as a cytoskeletal crosslinker and signaling scaffold, affecting mechanical as well as dynamic properties of the cytoskeleton. As a member of the plakin family of cytolinker proteins, plectin has a multidomain structure that is responsible for its vast binding portfolio. It not only binds to all types of IFs, actin filaments and microtubules, but also to transmembrane receptors, proteins of the subplasma membrane protein skeleton, components of the nuclear envelope, and several kinases with known roles in migration, proliferation, and energy metabolism of cells. Due to alternative splicing, plectin is expressed as various isoforms with differing N-terminal heads that dictate their differential subcellular targeting. Through specific interactions with other proteins at their target sites and their ability to bind to all types of IFs, plectin molecules provide strategically located IF anchorage sites within the cytoplasm of cells. In this review, we will present an overview of the structural features and functional properties of plectin and discuss recent progress in defining the role of its isoforms in stress-prone tissues and the implicated diseases, with focus on skin, skeletal muscle, and Schwann cells of peripheral nerve.
Collapse
Affiliation(s)
- Maria J. Castañón
- Max F. Perutz Laboratories, Department of Biochemistry and Cell Biology, University of Vienna, 1030 Vienna, Austria
| | - Gernot Walko
- Max F. Perutz Laboratories, Department of Biochemistry and Cell Biology, University of Vienna, 1030 Vienna, Austria
- Present Address: Centre for Stem Cells and Regenerative Medicine, King’s College London School of Medicine, 28th Floor, Tower Wing, Guy’s Hospital, Great Maze Pond, London, SE1 9RT UK
| | - Lilli Winter
- Max F. Perutz Laboratories, Department of Biochemistry and Cell Biology, University of Vienna, 1030 Vienna, Austria
- Present Address: Institute of Neuropathology, University Hospital Erlangen, Schwabachanlage 6, 91054 Erlangen, Germany
| | - Gerhard Wiche
- Max F. Perutz Laboratories, Department of Biochemistry and Cell Biology, University of Vienna, 1030 Vienna, Austria
| |
Collapse
|
20
|
Gardiner J. The evolution and diversification of plant microtubule-associated proteins. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 75:219-29. [PMID: 23551562 DOI: 10.1111/tpj.12189] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 03/11/2013] [Accepted: 03/22/2013] [Indexed: 05/07/2023]
Abstract
Plant evolution is marked by major advances in structural characteristics that facilitated the highly successful colonization of dry land. Underlying these advances is the evolution of genes encoding specialized proteins that form novel microtubular arrays of the cytoskeleton. This review investigates the evolution of plant families of microtubule-associated proteins (MAPs) through the recently sequenced genomes of Arabidopsis thaliana, Oryza sativa, Selaginella moellendorffii, Physcomitrella patens, Volvox carteri and Chlamydomonas reinhardtii. The families of MAPs examined are AIR9, CLASP, CRIPT, MAP18, MOR1, TON, EB1, AtMAP70, SPR2, SPR1, WVD2 and MAP65 families (abbreviations are defined in the footnote to Table 1). Conjectures are made regarding the evolution of MAPs in plants in relation to the evolution of multicellularity, oriented cell division and vasculature. Angiosperms in particular have high numbers of proteins that are involved in promotion of helical growth or its suppression, and novel plant microtubular structures may have acted as a catalyst for the development of novel plant MAPs. Comparisons of plant MAP gene families with those of animals show that animals may have more flexibility in the structure of their microtubule cytoskeletons than plants, but with both plants and animals possessing many MAP splice variants.
Collapse
Affiliation(s)
- John Gardiner
- School of Biological Sciences, The University of Sydney, Sydney, NSW 2006, Australia.
| |
Collapse
|
21
|
Sharp JA, Blower MD. Production of Xenopus tropicalis egg extracts to identify microtubule-associated RNAs. J Vis Exp 2013. [PMID: 23851481 PMCID: PMC3729184 DOI: 10.3791/50434] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Many organisms localize mRNAs to specific subcellular destinations to spatially and temporally control gene expression. Recent studies have demonstrated that the majority of the transcriptome is localized to a nonrandom position in cells and embryos. One approach to identify localized mRNAs is to biochemically purify a cellular structure of interest and to identify all associated transcripts. Using recently developed high-throughput sequencing technologies it is now straightforward to identify all RNAs associated with a subcellular structure. To facilitate transcript identification it is necessary to work with an organism with a fully sequenced genome. One attractive system for the biochemical purification of subcellular structures are egg extracts produced from the frog Xenopus laevis. However, X. laevis currently does not have a fully sequenced genome, which hampers transcript identification. In this article we describe a method to produce egg extracts from a related frog, X. tropicalis, that has a fully sequenced genome. We provide details for microtubule polymerization, purification and transcript isolation. While this article describes a specific method for identification of microtubule-associated transcripts, we believe that it will be easily applied to other subcellular structures and will provide a powerful method for identification of localized RNAs.
Collapse
Affiliation(s)
- Judith A Sharp
- Department of Molecular Biology, Massachusetts General Hospital, MA, USA
| | | |
Collapse
|
22
|
Valencia RG, Walko G, Janda L, Novacek J, Mihailovska E, Reipert S, Andrä-Marobela K, Wiche G. Intermediate filament-associated cytolinker plectin 1c destabilizes microtubules in keratinocytes. Mol Biol Cell 2013; 24:768-84. [PMID: 23363598 PMCID: PMC3596248 DOI: 10.1091/mbc.e12-06-0488] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The transition of microtubules (MTs) from an assembled to a disassembled state plays an essential role in several cellular functions. While MT dynamics are often linked to those of actin filaments, little is known about whether intermediate filaments (IFs) have an influence on MT dynamics. We show here that plectin 1c (P1c), one of the multiple isoforms of the IF-associated cytolinker protein plectin, acts as an MT destabilizer. We found that MTs in P1c-deficient (P1c(-/-)) keratinocytes are more resistant toward nocodazole-induced disassembly and display increased acetylation. In addition, live imaging of MTs in P1c(-/-), as well as in plectin-null, cells revealed decreased MT dynamics. Increased MT stability due to P1c deficiency led to changes in cell shape, increased velocity but loss of directionality of migration, smaller-sized focal adhesions, higher glucose uptake, and mitotic spindle aberrations combined with reduced growth rates of cells. On the basis of ex vivo and in vitro experimental approaches, we suggest a mechanism for MT destabilization in which isoform-specific binding of P1c to MTs antagonizes the MT-stabilizing and assembly-promoting function of MT-associated proteins through an inhibitory function exerted by plectin's SH3 domain. Our results open new perspectives on cytolinker-coordinated IF-MT interaction and its physiological significance.
Collapse
Affiliation(s)
- Rocio G Valencia
- Max F. Perutz Laboratories, Department of Biochemistry and Cell Biology, University of Vienna, A-1030 Vienna, Austria
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Lukinavičius G, Umezawa K, Olivier N, Honigmann A, Yang G, Plass T, Mueller V, Reymond L, Corrêa IR, Luo ZG, Schultz C, Lemke EA, Heppenstall P, Eggeling C, Manley S, Johnsson K. A near-infrared fluorophore for live-cell super-resolution microscopy of cellular proteins. Nat Chem 2013; 5:132-9. [PMID: 23344448 DOI: 10.1038/nchem.1546] [Citation(s) in RCA: 646] [Impact Index Per Article: 58.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Accepted: 11/28/2012] [Indexed: 12/19/2022]
Abstract
The ideal fluorescent probe for bioimaging is bright, absorbs at long wavelengths and can be implemented flexibly in living cells and in vivo. However, the design of synthetic fluorophores that combine all of these properties has proved to be extremely difficult. Here, we introduce a biocompatible near-infrared silicon-rhodamine probe that can be coupled specifically to proteins using different labelling techniques. Importantly, its high permeability and fluorogenic character permit the imaging of proteins in living cells and tissues, and its brightness and photostability make it ideally suited for live-cell super-resolution microscopy. The excellent spectroscopic properties of the probe combined with its ease of use in live-cell applications make it a powerful new tool for bioimaging.
Collapse
Affiliation(s)
- Gražvydas Lukinavičius
- Ecole Polytechnique Fédérale de Lausanne, Institute of Chemical Sciences and Engineering (ISIC), National Centre of Competence in Research (NCCR) in Chemical Biology, 1015 Lausanne, Switzerland
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Interplay Between Spindle Architecture and Function. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 306:83-125. [DOI: 10.1016/b978-0-12-407694-5.00003-1] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
25
|
Matsumoto K, Nakayama H, Yoshimura M, Masuda A, Dohmae N, Matsumoto S, Tsujimoto M. PRMT1 is required for RAP55 to localize to processing bodies. RNA Biol 2012; 9:610-23. [PMID: 22614839 DOI: 10.4161/rna.19527] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
In eukaryotic cells, components of messenger ribonucleoproteins (mRNPs) are often detected in cytoplasmic granules, such as processing bodies (P-bodies) and stress granules (SGs) where translationally repressed mRNAs accumulate. RAP55A, which is an RNA binding component of mRNPs, acts as a translational repressor and localizes to P-bodies and SGs. We found here that a homologous protein RAP55B also localized to P-bodies when expressed in human cultured cells. When RAP55A or RAP55B was highly expressed in the cells, they induced the formation of SG-like large cytoplasmic mRNP granules that contained both P-body and SG components, indicating that RAP55 is important for the assembly of cytoplasmic mRNP granules. In addition, we found that RAP55A associated with protein arginine methyltransferases PRMT1 and PRMT5. Multiple arginine residues of RAP55A were indeed asymmetrically dimethylated in the cell and PRMT1 was shown to be a component of large mRNP granules induced by RAP55A overexpression. Although PRMT1 did not accumulate in P-bodies, siRNA-mediated knockdown of PRMT1 impaired the localization of RAP55A to P-bodies, while other components were still retained in these structures. Thus, our data indicate that RAP55 is important for the assembly of cytoplasmic mRNP granules and that PRMT1 is required for RAP55A to localize to P-bodies.
Collapse
Affiliation(s)
- Ken Matsumoto
- Molecular Entomology Laboratory, RIKEN Advanced Science Institute, Wako, Saitama, Japan.
| | | | | | | | | | | | | |
Collapse
|
26
|
Secrier M, Pavlopoulos GA, Aerts J, Schneider R. Arena3D: visualizing time-driven phenotypic differences in biological systems. BMC Bioinformatics 2012; 13:45. [PMID: 22439608 PMCID: PMC3368716 DOI: 10.1186/1471-2105-13-45] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Accepted: 03/22/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Elucidating the genotype-phenotype connection is one of the big challenges of modern molecular biology. To fully understand this connection, it is necessary to consider the underlying networks and the time factor. In this context of data deluge and heterogeneous information, visualization plays an essential role in interpreting complex and dynamic topologies. Thus, software that is able to bring the network, phenotypic and temporal information together is needed. Arena3D has been previously introduced as a tool that facilitates link discovery between processes. It uses a layered display to separate different levels of information while emphasizing the connections between them. We present novel developments of the tool for the visualization and analysis of dynamic genotype-phenotype landscapes. RESULTS Version 2.0 introduces novel features that allow handling time course data in a phenotypic context. Gene expression levels or other measures can be loaded and visualized at different time points and phenotypic comparison is facilitated through clustering and correlation display or highlighting of impacting changes through time. Similarity scoring allows the identification of global patterns in dynamic heterogeneous data. In this paper we demonstrate the utility of the tool on two distinct biological problems of different scales. First, we analyze a medium scale dataset that looks at perturbation effects of the pluripotency regulator Nanog in murine embryonic stem cells. Dynamic cluster analysis suggests alternative indirect links between Nanog and other proteins in the core stem cell network. Moreover, recurrent correlations from the epigenetic to the translational level are identified. Second, we investigate a large scale dataset consisting of genome-wide knockdown screens for human genes essential in the mitotic process. Here, a potential new role for the gene lsm14a in cytokinesis is suggested. We also show how phenotypic patterning allows for extensive comparison and identification of high impact knockdown targets. CONCLUSIONS We present a new visualization approach for perturbation screens with multiple phenotypic outcomes. The novel functionality implemented in Arena3D enables effective understanding and comparison of temporal patterns within morphological layers, to help with the system-wide analysis of dynamic processes. Arena3D is available free of charge for academics as a downloadable standalone application from: http://arena3d.org/.
Collapse
Affiliation(s)
- Maria Secrier
- Structural and Computational Biology Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, Heidelberg 69117, Germany.
| | | | | | | |
Collapse
|
27
|
Froidevaux-Klipfel L, Poirier F, Boursier C, Crépin R, Poüs C, Baudin B, Baillet A. Modulation of septin and molecular motor recruitment in the microtubule environment of the Taxol-resistant human breast cancer cell line MDA-MB-231. Proteomics 2011; 11:3877-86. [PMID: 21761557 DOI: 10.1002/pmic.201000789] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Revised: 06/08/2011] [Accepted: 07/05/2011] [Indexed: 01/09/2023]
Abstract
Cell resistance to low doses of paclitaxel (Taxol) involves a modulation of microtubule (MT) dynamics. We applied a proteomic approach based on 2-DE coupled with MS to identify changes in the MT environment of Taxol-resistant breast cancer cells. Having established a proteomic pattern of the microtubular proteins extracted from MDA-MB-231 cells, we verified by Western blotting that in resistant cells, α- and β-tubulins (more specifically the βIII and βIV isotypes) increased. Interestingly, four septins (SEPT2, 8, 9 and 11), which are GTPases involved in cytokinesis and in MT/actin cytoskeleton organization, were overexpressed and enriched in the MT environment of Taxol-resistant cells compared to their sensitive counterpart. Changes in the MT proteome of resistant cells also comprised increased kinesin-1 heavy chain expression and recruitment on MTs while dynein light chain-1 was downregulated. Modulation of motor protein recruitment around MTs might reflect their important role in controlling MT dynamics via the organization of signaling pathways. The identification of proteins previously unknown to be linked to taxane-resistance could also be valuable to identify new biological markers of resistance.
Collapse
|
28
|
Bonner MK, Poole DS, Xu T, Sarkeshik A, Yates JR, Skop AR. Mitotic spindle proteomics in Chinese hamster ovary cells. PLoS One 2011; 6:e20489. [PMID: 21647379 PMCID: PMC3103581 DOI: 10.1371/journal.pone.0020489] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Accepted: 04/27/2011] [Indexed: 12/11/2022] Open
Abstract
Mitosis is a fundamental process in the development of all organisms. The mitotic spindle guides the cell through mitosis as it mediates the segregation of chromosomes, the orientation of the cleavage furrow, and the progression of cell division. Birth defects and tissue-specific cancers often result from abnormalities in mitotic events. Here, we report a proteomic study of the mitotic spindle from Chinese Hamster Ovary (CHO) cells. Four different isolations of metaphase spindles were subjected to Multi-dimensional Protein Identification Technology (MudPIT) analysis and tandem mass spectrometry. We identified 1155 proteins and used Gene Ontology (GO) analysis to categorize proteins into cellular component groups. We then compared our data to the previously published CHO midbody proteome and identified proteins that are unique to the CHO spindle. Our data represent the first mitotic spindle proteome in CHO cells, which augments the list of mitotic spindle components from mammalian cells.
Collapse
Affiliation(s)
- Mary Kate Bonner
- Department of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Daniel S. Poole
- Department of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Tao Xu
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Ali Sarkeshik
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California, United States of America
| | - John R. Yates
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Ahna R. Skop
- Department of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- * E-mail:
| |
Collapse
|
29
|
Korvatska O, Estes A, Munson J, Dawson G, Bekris LM, Kohen R, Yu CE, Schellenberg GD, Raskind WH. Mutations in the TSGA14 gene in families with autism spectrum disorders. Am J Med Genet B Neuropsychiatr Genet 2011; 156B:303-11. [PMID: 21438139 PMCID: PMC3552624 DOI: 10.1002/ajmg.b.31162] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Accepted: 11/30/2010] [Indexed: 11/11/2022]
Abstract
Linkage to 7q has been the most robust genetic finding in familial autism. A previous scan of multiplex families with autism spectrum disorders found a linkage signal of genome-wide significance at D7S530 on 7q32. We searched a candidate imprinted region at this location for genetic variants in families with positive linkage scores. Using exon resequencing, we identified three rare potentially pathogenic variants in the TSGA14 gene, which encodes a centrosomal protein. Two variants were missense mutations (c.664C>G; p.P206A and c.766T>G; p.C240G) that changed conserved residues in the same protein domain; the third variant (c.192+5G>A) altered splicing, which resulted in a protein with an internal deletion of 16 residues and a G33D substitution. These rare TSGA14 variants are enriched in the affected subjects (6/348 patients versus 2/670 controls, Fisher's exact two tailed P = 0.022). This is the first report of a possible link of a gene with a centrosomal function with familial autism.
Collapse
Affiliation(s)
- O Korvatska
- Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, 98195, USA.
| | - A Estes
- Department of Speech and Hearing Sciences, University of Washington, Seattle, WA, USA
| | - J Munson
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA
| | - G Dawson
- Autism Speaks, New York, NY, USA,Department of Psychiatry, University of North Carolina, Chapel Hill, NC, USA
| | - L M Bekris
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA, USA
| | - R Kohen
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA
| | - C-E Yu
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA, USA
| | - G D Schellenberg
- Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - W H Raskind
- Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, WA, USA,Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA
| |
Collapse
|
30
|
Seed proteomics. J Proteomics 2011; 74:389-400. [DOI: 10.1016/j.jprot.2010.12.004] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 12/08/2010] [Accepted: 12/10/2010] [Indexed: 12/29/2022]
|
31
|
Miernyk JA, Preťová A, Olmedilla A, Klubicová K, Obert B, Hajduch M. Using proteomics to study sexual reproduction in angiosperms. ACTA ACUST UNITED AC 2010; 24:9-22. [PMID: 20830489 DOI: 10.1007/s00497-010-0149-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Accepted: 08/21/2010] [Indexed: 12/18/2022]
Abstract
While a relative latecomer to the postgenomics era of functional biology, the application of mass spectrometry-based proteomic analysis has increased exponentially over the past 10 years. Some of this increase is the result of transition of chemists, physicists, and mathematicians to the study of biology, and some is due to improved methods, increased instrument sensitivity, and better techniques of bioinformatics-based data analysis. Proteomic Biological processes are typically studied in isolation, and seldom are efforts made to coordinate results obtained using structural, biochemical, and molecular-genetic strategies. Mass spectrometry-based proteomic analysis can serve as a platform to bridge these disparate results and to additionally incorporate both temporal and anatomical considerations. Recently, proteomic analyses have transcended their initial purely descriptive applications and are being employed extensively in studies of posttranslational protein modifications, protein interactions, and control of metabolic networks. Herein, we provide a brief introduction to sample preparation, comparison of gel-based versus gel-free methods, and explanation of data analysis emphasizing plant reproductive applications. We critically review the results from the relatively small number of extant proteomics-based analyses of angiosperm reproduction, from flowers to seedlings, and speculate on the utility of this strategy for future developments and directions.
Collapse
Affiliation(s)
- Ján A Miernyk
- Institute of Plant Genetics and Biotechnology, Slovak Academy of Sciences, Nitra, Slovak Republic
| | | | | | | | | | | |
Collapse
|
32
|
Kapitein LC, Hoogenraad CC. Which way to go? Cytoskeletal organization and polarized transport in neurons. Mol Cell Neurosci 2010; 46:9-20. [PMID: 20817096 DOI: 10.1016/j.mcn.2010.08.015] [Citation(s) in RCA: 163] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Accepted: 08/25/2010] [Indexed: 01/01/2023] Open
Abstract
To establish and maintain their polarized morphology, neurons employ active transport driven by cytoskeletal motor proteins to sort cargo between axons and dendrites. These motors can move in a specific direction over either microtubules (kinesins, dynein) or actin filaments (myosins). The basic traffic rules governing polarized transport on the neuronal cytoskeleton have long remained unclear, but recent work has revealed several fundamental sorting principles based on differences in the cytoskeletal organization in axons versus dendrites. We will highlight the basic characteristics of the neuronal cytoskeleton and review existing evidence for microtubule and actin based traffic rules in polarized neuronal transport. We will propose a model in which polarized sorting of cargo is established by recruiting or activating the proper subset of motor proteins, which are subsequently guided to specific directions by the polarized organization of the neuronal cytoskeleton.
Collapse
Affiliation(s)
- Lukas C Kapitein
- Department of Neuroscience, Erasmus Medical Center, Dr. Molewaterplein 50, 3015 GE, Rotterdam, The Netherlands
| | | |
Collapse
|
33
|
Proteome analysis of microtubule-associated proteins and their interacting partners from mammalian brain. Amino Acids 2010; 41:363-85. [PMID: 20567863 DOI: 10.1007/s00726-010-0649-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Accepted: 06/01/2010] [Indexed: 10/19/2022]
Abstract
The microtubule (MT) cytoskeleton is essential for a variety of cellular processes. MTs are finely regulated by distinct classes of MT-associated proteins (MAPs), which themselves bind to and are regulated by a large number of additional proteins. We have carried out proteome analyses of tubulin-rich and tubulin-depleted MAPs and their interacting partners isolated from bovine brain. In total, 573 proteins were identified giving us unprecedented access to brain-specific MT-associated proteins from mammalian brain. Most of the standard MAPs were identified and at least 500 proteins have been reported as being associated with MTs. We identified protein complexes with a large number of subunits such as brain-specific motor/adaptor/cargo complexes for kinesins, dynein, and dynactin, and proteins of an RNA-transporting granule. About 25% of the identified proteins were also found in the synaptic vesicle proteome. Analysis of the MS/MS data revealed many posttranslational modifications, amino acid changes, and alternative splice variants, particularly in tau, a key protein implicated in Alzheimer's disease. Bioinformatic analysis of known protein-protein interactions of the identified proteins indicated that the number of MAPs and their associated proteins is larger than previously anticipated and that our database will be a useful resource to identify novel binding partners.
Collapse
|