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Subbiah A, Caswell DL, Turner K, Jaiswal A, Avidor-Reiss T. CP110 and CEP135 Localize Near the Proximal Centriolar Remnants of Mice Spermatozoa. MICROPUBLICATION BIOLOGY 2024; 2024:10.17912/micropub.biology.001083. [PMID: 38351906 PMCID: PMC10862134 DOI: 10.17912/micropub.biology.001083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 01/17/2024] [Accepted: 01/18/2024] [Indexed: 02/16/2024]
Abstract
Centrioles form centrosomes that organize microtubules, assist in cell structure, and nucleate cilia that provide motility and sensation. Within the sperm, the centrosome consists of two centrioles (proximal and distal centriole) and a pericentriolar material known as the striated column and capitulum. The distal centriole nucleates the flagellum. Mice spermatozoa, unlike other mammal spermatozoa (e.g., human and bovine), have no ultra-structurally recognizable centrioles, but their neck has the centriolar proteins POC1B and FAM161A, suggesting mice spermatozoa have remnant centrioles. Here, we examine whether other centriolar proteins, CP110 and CEP135, found in the human and bovine spermatozoa centrioles are also found in the mouse spermatozoa neck. CP110 is a tip protein controlling ciliogenesis, and CEP135 is a centriole-specific structural protein in the centriole base of canonical centrioles found in most cell types. Here, we report that CP110 and CEP135 were both located in the mice spermatozoa neck around the proximal centriolar remnants labeled by POC1B, increasing the number of centriolar proteins found in the mice spermatozoa neck, further supporting the hypothesis that a remnant proximal centriole is present in mice.
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Rajeev R, Mukhopadhyay S, Bhagyanath S, Devu Priya MRS, Manna TK. TACC3-ch-TOG interaction regulates spindle microtubule assembly by controlling centrosomal recruitment of γ-TuRC. Biosci Rep 2023; 43:232568. [PMID: 36790370 PMCID: PMC10037420 DOI: 10.1042/bsr20221882] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 02/07/2023] [Accepted: 02/14/2023] [Indexed: 02/16/2023] Open
Abstract
γ-Tubulin ring complex (γ-TuRC), composed of γ-tubulin and multiple γ-tubulin complex proteins (GCPs), serves as the major microtubule nucleating complex in animal cells. However, several γ-TuRC-associated proteins have been shown to control its function. Centrosomal adaptor protein, TACC3, is one such γ-TuRC-interacting factor that is essential for proper mitotic spindle assembly across organisms. ch-TOG is another microtubule assembly promoting protein, which interacts with TACC3 and cooperates in mitotic spindle assembly. However, the mechanism how TACC3-ch-TOG interaction regulates microtubule assembly and the γ-TuRC functions at the centrosomes remain unclear. Here, we show that deletion of the ch-TOG-binding region in TACC3 enhances recruitment of the γ-TuRC proteins to centrosomes and aggravates spindle microtubule assembly in human cells. Loss of TACC3-ch-TOG binding imparts stabilization on TACC3 interaction with the γ-TuRC proteins and it does so by stimulating TACC3 phosphorylation and thereby enhancing phospho-TACC3 recruitment to the centrosomes. We also show that localization of ch-TOG at the centrosomes is substantially reduced and the same on the spindle microtubules is increased in its TACC3-unbound condition. Additional results reveal that ch-TOG depletion stimulates γ-tubulin localization on the spindles without significantly affecting the centrosomal γ-tubulin level. The results indicate that ch-TOG binding to TACC3 controls TACC3 phosphorylation and TACC3-mediated stabilization of the γ-TuRCs at the centrosomes. They also implicate that the spatio-temporal control of TACC3 phosphorylation via ch-TOG-binding ensures mitotic spindle assembly to the optimal level.
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Affiliation(s)
- Resmi Rajeev
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram 695551, India
| | - Swarnendu Mukhopadhyay
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram 695551, India
| | - Suresh Bhagyanath
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram 695551, India
| | - Manu Rani S Devu Priya
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram 695551, India
| | - Tapas K Manna
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram 695551, India
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Ma D, Wang F, Teng J, Huang N, Chen J. Structure and function of distal and subdistal appendages of the mother centriole. J Cell Sci 2023; 136:286880. [PMID: 36727648 DOI: 10.1242/jcs.260560] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Centrosomes are composed of centrioles surrounded by pericentriolar material. The two centrioles in G1 phase are distinguished by the localization of their appendages in the distal and subdistal regions; the centriole possessing both types of appendage is older and referred to as the mother centriole, whereas the other centriole lacking appendages is the daughter centriole. Both distal and subdistal appendages in vertebrate cells consist of multiple proteins assembled in a hierarchical manner. Distal appendages function mainly in the initial process of ciliogenesis, and subdistal appendages are involved in microtubule anchoring, mitotic spindle regulation and maintenance of ciliary signaling. Mutations in genes encoding components of both appendage types are implicated in ciliopathies and developmental defects. In this Review, we discuss recent advances in knowledge regarding the composition and assembly of centriolar appendages, as well as their roles in development and disease.
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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 100871, China
| | - Fulin Wang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing 100871, China
| | - Junlin Teng
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing 100871, China
| | - Ning Huang
- Institute of Neuroscience, Translational Medicine Institute, Health Science Center, Xi'an Jiaotong University, Xi'an 710061, China.,Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Health Science Center, Xi'an Jiaotong University, Xi'an 710061, China
| | - Jianguo Chen
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing 100871, China.,Center for Quantitative Biology, Peking University, Beijing 100871, China
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Fang Z, Gao ZJ, Yu X, Sun SR, Yao F. Identification of a centrosome-related prognostic signature for breast cancer. Front Oncol 2023; 13:1138049. [PMID: 37035151 PMCID: PMC10073657 DOI: 10.3389/fonc.2023.1138049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 03/09/2023] [Indexed: 04/11/2023] Open
Abstract
Background As the major microtubule organizing center in animal cells, the centrosome is implicated with human breast tumor in multiple ways, such as promotion of tumor cell immune evasion. Here, we aimed to detect the expression of centrosome-related genes (CRGs) in normal and malignant breast tissues, and construct a novel centrosome-related prognostic model to discover new biomarkers and screen drugs for breast cancer. Methods We collected CRGs from the public databases and literature. The differentially expressed CRGs between normal and malignant breast tissues were identified by the DESeq2. Univariate Cox and LASSO regression analyses were conducted to screen candidate prognostic CRGs and develop a centrosome-related signature (CRS) to score breast cancer patients. We further manipulated and visualized data from TCGA, GEO, IMvigor210, TCIA and TIMER to explore the correlation between CRS and patient outcomes, clinical manifestations, mutational landscapes, tumor immune microenvironments, and responses to diverse therapies. Single cell analyses were performed to investigate the difference of immune cell landscape between high- and low-risk group patients. In addition, we constructed a nomogram to guide clinicians in precise treatment. Results A total of 726 CRGs were collected from the public databases and literature. PSME2, MAPK10, EIF4EBP1 were screened as the prognostic genes in breast cancer. Next, we constructed a centrosome-related prognostic signature and validated its efficacy based on the genes for predicting the survival of breast cancer patients. The high-risk group patients had poor prognoses, the area under the ROC curve for 1-, 3-, and 5-year overall survival (OS) was 0.77, 0.67, and 0.65, respectively. The predictive capacity of CRS was validated by other datasets from GEO dataset. In addition, high-risk group patients exhibited elevated level of mutational landscapes and decreased level of immune infiltration, especially T and B lymphocytes. In terms of treatment responses, patients in the high-risk group were found to be resistant to immunotherapy but sensitive to chemotherapy. Moreover, we screened a series of candidate anticancer drugs with high sensitivity in the high-risk group. Conclusion Our work exploited a centrosome-related prognostic signature and developed a predictive nomogram capable of accurately predicting breast cancer OS. The above discoveries provide deeper insights into the vital roles of the centrosome and contribute to the development of personalized treatment for breast cancer.
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Affiliation(s)
| | | | | | | | - Feng Yao
- *Correspondence: Feng Yao, ; Sheng-Rong Sun,
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5
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Palacios Martínez S, Greaney J, Zenker J. Beyond the centrosome: The mystery of microtubule organising centres across mammalian preimplantation embryos. Curr Opin Cell Biol 2022; 77:102114. [PMID: 35841745 DOI: 10.1016/j.ceb.2022.102114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 05/25/2022] [Accepted: 06/11/2022] [Indexed: 11/18/2022]
Abstract
Mammalian preimplantation embryogenesis depends on the spatio-temporal dynamics of the microtubule cytoskeleton to enable exceptionally fast changes in cell number, function, architecture, and fate. Microtubule organising centres (MTOCs), which coordinate the remodelling of microtubules, are therefore of fundamental significance during the first days of a new life. Despite its indispensable role during early mammalian embryogenesis, the origin of microtubule growth remains poorly understood. In this review, we summarise the most recent discoveries on microtubule organisation and function during early human embryogenesis and compare these to innovative studies conducted in alternative mammalian models. We emphasise the differences and analogies of centriole inheritance and their role during the first cleavage. Furthermore, we highlight the significance of non-centrosomal MTOCs for embryo viability and discuss the potential of novel in vitro models and light-inducible approaches towards unravelling microtubule formation in research and assisted reproductive technologies.
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Affiliation(s)
| | - Jessica Greaney
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
| | - Jennifer Zenker
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia.
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6
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Amargant F, Pujol A, Ferrer-Vaquer A, Durban M, Martínez M, Vassena R, Vernos I. The human sperm basal body is a complex centrosome important for embryo preimplantation development. Mol Hum Reprod 2021; 27:6377343. [PMID: 34581808 PMCID: PMC8561016 DOI: 10.1093/molehr/gaab062] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 09/09/2021] [Indexed: 12/28/2022] Open
Abstract
The mechanism of conversion of the human sperm basal body to a centrosome after fertilization, and its role in supporting human early embryogenesis, has not been directly addressed so far. Using proteomics and immunofluorescence studies, we show here that the human zygote inherits a basal body enriched with centrosomal proteins from the sperm, establishing the first functional centrosome of the new organism. Injection of human sperm tails containing the basal body into human oocytes followed by parthenogenetic activation, showed that the centrosome contributes to the robustness of the early cell divisions, increasing the probability of parthenotes reaching the compaction stage. In the absence of the sperm-derived centrosome, pericentriolar material (PCM) components stored in the oocyte can form de novo structures after genome activation, suggesting a tight PCM expression control in zygotes. Our results reveal that the sperm basal body is a complex organelle which converts to a centrosome after fertilization, ensuring the early steps of embryogenesis and successful compaction. However, more experiments are needed to elucidate the exact molecular mechanisms of centrosome inheritance in humans.
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Affiliation(s)
- Farners Amargant
- Clínica EUGIN-Eugin Group, Barcelona, Spain.,Cell and Developmental Biology Programme, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Aïda Pujol
- Centro de Infertilidad y Reproducción Humana (CIRH)-Eugin Group, Barcelona, Spain
| | | | | | | | | | - Isabelle Vernos
- Cell and Developmental Biology Programme, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain.,Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, Spain
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Ryniawec JM, Rogers GC. Centrosome instability: when good centrosomes go bad. Cell Mol Life Sci 2021; 78:6775-6795. [PMID: 34476544 PMCID: PMC8560572 DOI: 10.1007/s00018-021-03928-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 08/10/2021] [Accepted: 08/26/2021] [Indexed: 02/06/2023]
Abstract
The centrosome is a tiny cytoplasmic organelle that organizes and constructs massive molecular machines to coordinate diverse cellular processes. Due to its many roles during both interphase and mitosis, maintaining centrosome homeostasis is essential to normal health and development. Centrosome instability, divergence from normal centrosome number and structure, is a common pathognomonic cellular state tightly associated with cancers and other genetic diseases. As novel connections are investigated linking the centrosome to disease, it is critical to understand the breadth of centrosome functions to inspire discovery. In this review, we provide an introduction to normal centrosome function and highlight recent discoveries that link centrosome instability to specific disease states.
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Affiliation(s)
- John M Ryniawec
- University of Arizona Cancer Center, University of Arizona, 1515 N. Campbell Ave., Tucson, AZ, 85724, USA
| | - Gregory C Rogers
- University of Arizona Cancer Center, University of Arizona, 1515 N. Campbell Ave., Tucson, AZ, 85724, USA.
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8
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Fujii S, Kurokawa K, Tago T, Inaba R, Takiguchi A, Nakano A, Satoh T, Satoh AK. Sec71 separates Golgi stacks in Drosophila S2 cells. J Cell Sci 2020; 133:jcs245571. [PMID: 33262309 PMCID: PMC10668125 DOI: 10.1242/jcs.245571] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 11/18/2020] [Indexed: 01/19/2023] Open
Abstract
Golgi stacks are the basic structural units of the Golgi. Golgi stacks are separated from each other and scattered in the cytoplasm of Drosophila cells. Here, we report that the ARF-GEF inhibitor Brefeldin A (BFA) induces the formation of BFA bodies, which are aggregates of Golgi stacks, trans-Golgi networks and recycling endosomes. Recycling endosomes are located in the centers of BFA bodies, while Golgi stacks surround them on their trans sides. Live imaging of S2 cells revealed that Golgi stacks repeatedly merged and separated on their trans sides, and BFA caused successive merger by inhibiting separation, forming BFA bodies. S2 cells carrying genome-edited BFA-resistant mutant Sec71M717L did not form BFA bodies at high concentrations of BFA; S2 cells carrying genome-edited BFA-hypersensitive mutant Sec71F713Y produced BFA bodies at low concentrations of BFA. These results indicate that Sec71 is the sole BFA target for BFA body formation and controls Golgi stack separation. Finally, we showed that impairment of Sec71 in fly photoreceptors induces BFA body formation, with accumulation of both apical and basolateral cargoes, resulting in inhibition of polarized transport.
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Affiliation(s)
- Syara Fujii
- Program of Life and Environmental Science, Graduate School of Integral Science for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521, Japan
| | - Kazuo Kurokawa
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Tatsuya Tago
- Program of Life and Environmental Science, Graduate School of Integral Science for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521, Japan
| | - Ryota Inaba
- Program of Life and Environmental Science, Graduate School of Integral Science for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521, Japan
| | - Arata Takiguchi
- Program of Life and Environmental Science, Graduate School of Integral Science for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521, Japan
| | - Akihiko Nakano
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Takunori Satoh
- Program of Life and Environmental Science, Graduate School of Integral Science for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521, Japan
| | - Akiko K Satoh
- Program of Life and Environmental Science, Graduate School of Integral Science for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521, Japan
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Gonzalez C. Centrosomes in asymmetric cell division. Curr Opin Struct Biol 2020; 66:178-182. [PMID: 33279730 DOI: 10.1016/j.sbi.2020.10.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 10/07/2020] [Accepted: 10/18/2020] [Indexed: 02/04/2023]
Abstract
Asymmetric cell division (ACD) is a strategy for achieving cell diversity. Research carried out over the last two decades has shown that in some cell types that divide asymmetrically, mother and daughter centrosomes are noticeably different from one another in structure, behaviour, and fate, and that robust ACD depends upon centrosome function. Here, I review the latest advances in this field with special emphasis on the complex structure-function relationship of centrosomes with regards to ACD and on mechanistic insight derived from cell types that divide symmetrically but is likely to be relevant in ACD. I also include a comment arguing for the need to investigate the centrosome cycle in other cell types that divide asymmetrically.
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Affiliation(s)
- Cayetano Gonzalez
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac, 10, 08028 Barcelona, Spain; Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain.
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10
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Rajeev R, Singh P, Asmita A, Anand U, Manna TK. Aurora A site specific TACC3 phosphorylation regulates astral microtubule assembly by stabilizing γ-tubulin ring complex. BMC Mol Cell Biol 2019; 20:58. [PMID: 31823729 PMCID: PMC6902513 DOI: 10.1186/s12860-019-0242-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 11/25/2019] [Indexed: 11/15/2022] Open
Abstract
Background Astral microtubules emanating from the mitotic centrosomes play pivotal roles in defining cell division axis and tissue morphogenesis. Previous studies have demonstrated that human transforming acidic coiled-coil 3 (TACC3), the most conserved TACC family protein, regulates formation of astral microtubules at centrosomes in vertebrate cells by affecting γ-tubulin ring complex (γ-TuRC) assembly. However, the molecular mechanisms underlying such function were not completely understood. Results Here, we show that Aurora A site-specific phosphorylation in TACC3 regulates formation of astral microtubules by stabilizing γ-TuRC assembly in human cells. Mutation of the most conserved Aurora A targeting site, Ser 558 to alanine (S558A) in TACC3 results in robust loss of astral microtubules and disrupts localization of the γ-tubulin ring complex (γ-TuRC) proteins at the spindle poles. Under similar condition, phospho-mimicking S558D mutation retains astral microtubules and the γ-TuRC proteins in a manner similar to control cells expressed with wild type TACC3. Time-lapse imaging reveals that S558A mutation leads to defects in positioning of the spindle-poles and thereby causes delay in metaphase to anaphase transition. Biochemical results determine that the Ser 558- phosphorylated TACC3 interacts with the γ-TuRC proteins and further, S558A mutation impairs the interaction. We further reveal that the mutation affects the assembly of γ-TuRC from the small complex components. Conclusions The results demonstrate that TACC3 phosphorylation stabilizes γ- tubulin ring complex assembly and thereby regulates formation of centrosomal asters. They also implicate a potential role of TACC3 phosphorylation in the functional integrity of centrosomes/spindle poles.
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Affiliation(s)
- Resmi Rajeev
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Vithura, Thiruvananthapuram, 695551, India
| | - Puja Singh
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Vithura, Thiruvananthapuram, 695551, India.,Present Address: Centre for Cellular and Molecular Biology, Uppal Rd, Hyderabad, 500007, India
| | - Ananya Asmita
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Vithura, Thiruvananthapuram, 695551, India
| | - Ushma Anand
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Vithura, Thiruvananthapuram, 695551, India
| | - Tapas K Manna
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Vithura, Thiruvananthapuram, 695551, India.
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11
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Abstract
Microtubules are cytoskeletal filaments that are intrinsically polarized, with two structurally and functionally distinct ends, the plus end and the minus end. Over the last decade, numerous studies have shown that microtubule plus-end dynamics play an important role in many vital cellular processes and are controlled by numerous factors, such as microtubule plus-end-tracking proteins (+TIPs). In contrast, the cellular machinery that controls the behavior and organization of microtubule minus ends remains one of the least well-understood facets of the microtubule cytoskeleton. The recent characterization of the CAMSAP/Patronin/Nezha family members as specific 'minus-end-targeting proteins' ('-TIPs') has provided important new insights into the mechanisms governing minus-end dynamics. Here, we review the current state of knowledge on how microtubule minus ends are controlled and how minus-end regulators contribute to non-centrosomal microtubule organization and function during cell division, migration and differentiation.
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12
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Genetic Defects in TAPT1 Disrupt Ciliogenesis and Cause a Complex Lethal Osteochondrodysplasia. Am J Hum Genet 2015; 97:521-34. [PMID: 26365339 DOI: 10.1016/j.ajhg.2015.08.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 08/18/2015] [Indexed: 11/22/2022] Open
Abstract
The evolutionarily conserved transmembrane anterior posterior transformation 1 protein, encoded by TAPT1, is involved in murine axial skeletal patterning, but its cellular function remains unknown. Our study demonstrates that TAPT1 mutations underlie a complex congenital syndrome, showing clinical overlap between lethal skeletal dysplasias and ciliopathies. This syndrome is characterized by fetal lethality, severe hypomineralization of the entire skeleton and intra-uterine fractures, and multiple congenital developmental anomalies affecting the brain, lungs, and kidneys. We establish that wild-type TAPT1 localizes to the centrosome and/or ciliary basal body, whereas defective TAPT1 mislocalizes to the cytoplasm and disrupts Golgi morphology and trafficking and normal primary cilium formation. Knockdown of tapt1b in zebrafish induces severe craniofacial cartilage malformations and delayed ossification, which is shown to be associated with aberrant differentiation of cranial neural crest cells.
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13
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A Mechanism for Sustained Cellulose Synthesis during Salt Stress. Cell 2015; 162:1353-64. [PMID: 26343580 DOI: 10.1016/j.cell.2015.08.028] [Citation(s) in RCA: 193] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 05/12/2015] [Accepted: 07/23/2015] [Indexed: 12/11/2022]
Abstract
Abiotic stress, such as salinity, drought, and cold, causes detrimental yield losses for all major plant crop species. Understanding mechanisms that improve plants' ability to produce biomass, which largely is constituted by the plant cell wall, is therefore of upmost importance for agricultural activities. Cellulose is a principal component of the cell wall and is synthesized by microtubule-guided cellulose synthase enzymes at the plasma membrane. Here, we identified two components of the cellulose synthase complex, which we call companion of cellulose synthase (CC) proteins. The cytoplasmic tails of these membrane proteins bind to microtubules and promote microtubule dynamics. This activity supports microtubule organization, cellulose synthase localization at the plasma membrane, and renders seedlings less sensitive to stress. Our findings offer a mechanistic model for how two molecular components, the CC proteins, sustain microtubule organization and cellulose synthase localization and thus aid plant biomass production during salt stress. VIDEO ABSTRACT.
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14
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Styczynska-Soczka K, Jarman AP. The Drosophila homologue of Rootletin is required for mechanosensory function and ciliary rootlet formation in chordotonal sensory neurons. Cilia 2015; 4:9. [PMID: 26140210 PMCID: PMC4489026 DOI: 10.1186/s13630-015-0018-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 05/26/2015] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND In vertebrates, rootletin is the major structural component of the ciliary rootlet and is also part of the tether linking the centrioles of the centrosome. Various functions have been ascribed to the rootlet, including maintenance of ciliary integrity through anchoring and facilitation of transport to the cilium or at the base of the cilium. In Drosophila, Rootletin function has not been explored. RESULTS In the Drosophila embryo, Rootletin is expressed exclusively in cell lineages of type I sensory neurons, the only somatic cells bearing a cilium. Expression is strongest in mechanosensory chordotonal neurons. Knock-down of Rootletin results in loss of ciliary rootlet in these neurons and severe disruption of their sensory function. However, the sensory cilium appears largely normal in structure and in localisation of proteins suggesting no strong defect in ciliogenesis. No evidence was found for a defect in cell division. CONCLUSIONS The role of Rootletin as a component of the ciliary rootlet is conserved in Drosophila. In contrast, lack of a general role in cell division is consistent with lack of centriole tethering during the centrosome cycle in Drosophila. Although our evidence is consistent with an anchoring role for the rootlet, severe loss of mechanosensory function of chordotonal (Ch) neurons upon Rootletin knock-down may suggest a direct role for the rootlet in the mechanotransduction mechanism itself.
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Affiliation(s)
| | - Andrew P Jarman
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, EH8 9XD UK
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15
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Reina J, Gonzalez C. When fate follows age: unequal centrosomes in asymmetric cell division. Philos Trans R Soc Lond B Biol Sci 2015; 369:rstb.2013.0466. [PMID: 25047620 PMCID: PMC4113110 DOI: 10.1098/rstb.2013.0466] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
A strong correlation between centrosome age and fate has been reported in some stem cells and progenitors that divide asymmetrically. In some cases, such stereotyped centrosome behaviour is essential to endow stemness to only one of the two daughters, whereas in other cases causality is still uncertain. Here, we present the different cell types in which correlated centrosome age and fate has been documented, review current knowledge on the underlying molecular mechanisms and discuss possible functional implications of this process.
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Affiliation(s)
- Jose Reina
- Institute for Research in Biomedicine (IRB-Barcelona), Baldiri Reixac 10, Barcelona 08028, Spain
| | - Cayetano Gonzalez
- Institute for Research in Biomedicine (IRB-Barcelona), Baldiri Reixac 10, Barcelona 08028, Spain Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys 23, Barcelona 08010, Spain
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16
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Abstract
In recent years, our views on how DNA and genes are organised and regulated have evolved significantly. One example is provided by reports that single DNA strands in the double helix could carry distinct forms of information. That chromatids carrying old and nascently replicated DNA strands are recognised by the mitotic machinery, then segregated in a concerted way to distinct daughter cells after cell division is remarkable. Notably, this phenomenon in several cases has been associated with the cell fate choice of resulting daughter cells. Here, we review the evidence for asymmetric or template DNA strand segregation in mammals with a focus on skeletal muscle.
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Affiliation(s)
- Brendan Evano
- Institut Pasteur, Stem Cells & Development, Department of Developmental & Stem Cell Biology, CNRS URA 2578, 25 rue du Dr. Roux, Paris 75015, France
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17
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Shaheen R, Shamseldin HE, Loucks CM, Seidahmed MZ, Ansari S, Ibrahim Khalil M, Al-Yacoub N, Davis EE, Mola NA, Szymanska K, Herridge W, Chudley AE, Chodirker BN, Schwartzentruber J, Majewski J, Katsanis N, Poizat C, Johnson CA, Parboosingh J, Boycott KM, Innes AM, Alkuraya FS. Mutations in CSPP1, encoding a core centrosomal protein, cause a range of ciliopathy phenotypes in humans. Am J Hum Genet 2014; 94:73-9. [PMID: 24360803 PMCID: PMC3882732 DOI: 10.1016/j.ajhg.2013.11.010] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Accepted: 11/13/2013] [Indexed: 11/22/2022] Open
Abstract
Ciliopathies are characterized by a pattern of multisystem involvement that is consistent with the developmental role of the primary cilium. Within this biological module, mutations in genes that encode components of the cilium and its anchoring structure, the basal body, are the major contributors to both disease causality and modification. However, despite rapid advances in this field, the majority of the genes that drive ciliopathies and the mechanisms that govern the pronounced phenotypic variability of this group of disorders remain poorly understood. Here, we show that mutations in CSPP1, which encodes a core centrosomal protein, are disease causing on the basis of the independent identification of two homozygous truncating mutations in three consanguineous families (one Arab and two Hutterite) affected by variable ciliopathy phenotypes ranging from Joubert syndrome to the more severe Meckel-Gruber syndrome with perinatal lethality and occipital encephalocele. Consistent with the recently described role of CSPP1 in ciliogenesis, we show that mutant fibroblasts from one affected individual have severely impaired ciliogenesis with concomitant defects in sonic hedgehog (SHH) signaling. Our results expand the list of centrosomal proteins implicated in human ciliopathies.
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Affiliation(s)
- Ranad Shaheen
- Department of Genetics, King Faisal Specialist Hospital, Riyadh 11211, Saudi Arabia
| | - Hanan E Shamseldin
- Department of Genetics, King Faisal Specialist Hospital, Riyadh 11211, Saudi Arabia
| | - Catrina M Loucks
- Department of Medical Genetics, University of Calgary, Alberta Children's Hospital, Calgary, AB T3B 6A8, Canada
| | | | - Shinu Ansari
- Department of Genetics, King Faisal Specialist Hospital, Riyadh 11211, Saudi Arabia
| | - Mohamed Ibrahim Khalil
- Department of Obstetrics and Gynecology, Security Forces Hospital, Riyadh 11481, Saudi Arabia
| | - Nadya Al-Yacoub
- Cardiovascular Research Program, King Faisal Specialist Hospital and Research Center, Riyadh 11211, Saudi Arabia
| | - Erica E Davis
- Center for Human Disease Modeling, Duke University, Durham, NC 22710, USA
| | - Natalie A Mola
- Center for Human Disease Modeling, Duke University, Durham, NC 22710, USA
| | - Katarzyna Szymanska
- Leeds Institute of Molecular Medicine, St. James's University Hospital, Beckett Street, Leeds, West Yorkshire LS9 7TF, UK
| | - Warren Herridge
- Leeds Institute of Molecular Medicine, St. James's University Hospital, Beckett Street, Leeds, West Yorkshire LS9 7TF, UK
| | - Albert E Chudley
- Department of Paediatrics and Child Health and Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, MB R3A 1R9, Canada
| | - Bernard N Chodirker
- Department of Paediatrics and Child Health and Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, MB R3A 1R9, Canada
| | | | - Jacek Majewski
- McGill University and Genome Quebec Innovation Center, Montreal, QC H3A 0G4, Canada
| | - Nicholas Katsanis
- Center for Human Disease Modeling, Duke University, Durham, NC 22710, USA
| | - Coralie Poizat
- Cardiovascular Research Program, King Faisal Specialist Hospital and Research Center, Riyadh 11211, Saudi Arabia
| | - Colin A Johnson
- Leeds Institute of Molecular Medicine, St. James's University Hospital, Beckett Street, Leeds, West Yorkshire LS9 7TF, UK
| | - Jillian Parboosingh
- Department of Medical Genetics, University of Calgary, Alberta Children's Hospital, Calgary, AB T3B 6A8, Canada; Alberta Children's Hospital Research Institute for Child and Maternal Health, University of Calgary, Calgary, AB T3B 6A8, Canada
| | - Kym M Boycott
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, ON K1H 8L1, Canada
| | - A Micheil Innes
- Department of Medical Genetics, University of Calgary, Alberta Children's Hospital, Calgary, AB T3B 6A8, Canada; Alberta Children's Hospital Research Institute for Child and Maternal Health, University of Calgary, Calgary, AB T3B 6A8, Canada.
| | - Fowzan S Alkuraya
- Department of Genetics, King Faisal Specialist Hospital, Riyadh 11211, Saudi Arabia; Department of Anatomy and Cell Biology, College of Medicine, Alfaisal University, Riyadh 11533, Saudi Arabia.
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18
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Nye J, Buster DW, Rogers GC. The use of cultured Drosophila cells for studying the microtubule cytoskeleton. Methods Mol Biol 2014; 1136:81-101. [PMID: 24633795 DOI: 10.1007/978-1-4939-0329-0_6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Cultured Drosophila cell lines have been developed into a powerful tool for studying a wide variety of cellular processes. Their ability to be easily and cheaply cultured as well as their susceptibility to protein knockdown via double-stranded RNA-mediated interference (RNAi) has made them the model system of choice for many researchers in the fields of cell biology and functional genomics. Here we describe basic techniques for gene knockdown, transgene expression, preparation for fluorescence microscopy, and centrosome enrichment using cultured Drosophila cells with an emphasis on studying the microtubule cytoskeleton.
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Affiliation(s)
- Jonathan Nye
- Department of Cellular & Molecular Medicine, Arizona Cancer Center, Room 3951, University of Arizona, 1515 N. Campbell Avenue, Tucson, AZ, 85724, USA
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19
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Kloc M, Kubiak JZ, Li XC, Ghobrial RM. The newly found functions of MTOC in immunological response. J Leukoc Biol 2013; 95:417-30. [DOI: 10.1189/jlb.0813468] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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20
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Marthiens V, Piel M, Basto R. Never tear us apart--the importance of centrosome clustering. J Cell Sci 2013; 125:3281-92. [PMID: 22956721 DOI: 10.1242/jcs.094797] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The presence of more than two centrosomes (centrosome amplification) at the onset of mitosis has long been associated with multipolar spindle formation, and with the generation of genetic instability. However, in recent years, several studies have shown that a process termed 'centrosome clustering' actively contributes to bipolar division by promoting the gathering of extra centrosomes in two main poles. In this Commentary, we describe the main proteins that are involved in centriole duplication and discuss how centrosome amplification can be generated both in vitro and in vivo. We then summarize what is currently known about the processes that contribute to bipolar spindle formation when extra centrosomes are present, and which forces contribute to this process. Finally, we discuss how extra centrosomes might contribute to tumorigenesis, giving emphasis to the role of centrosome amplification in promoting genetic instability.
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21
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Lindeboom JJ, Lioutas A, Deinum EE, Tindemans SH, Ehrhardt DW, Emons AMC, Vos JW, Mulder BM. Cortical microtubule arrays are initiated from a nonrandom prepattern driven by atypical microtubule initiation. PLANT PHYSIOLOGY 2013; 161:1189-201. [PMID: 23300168 PMCID: PMC3585589 DOI: 10.1104/pp.112.204057] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Accepted: 01/04/2013] [Indexed: 05/23/2023]
Abstract
The ordered arrangement of cortical microtubules in growing plant cells is essential for anisotropic cell expansion and, hence, for plant morphogenesis. These arrays are dismantled when the microtubule cytoskeleton is rearranged during mitosis and reassembled following completion of cytokinesis. The reassembly of the cortical array has often been considered as initiating from a state of randomness, from which order arises at least partly through self-organizing mechanisms. However, some studies have shown evidence for ordering at early stages of array assembly. To investigate how cortical arrays are initiated in higher plant cells, we performed live-cell imaging studies of cortical array assembly in tobacco (Nicotiana tabacum) Bright Yellow-2 cells after cytokinesis and drug-induced disassembly. We found that cortical arrays in both cases did not initiate randomly but with a significant overrepresentation of microtubules at diagonal angles with respect to the cell axis, which coincides with the predominant orientation of the microtubules before their disappearance from the cell cortex in preprophase. In Arabidopsis (Arabidopsis thaliana) root cells, recovery from drug-induced disassembly was also nonrandom and correlated with the organization of the previous array, although no diagonal bias was observed in these cells. Surprisingly, during initiation, only about one-half of the new microtubules were nucleated from locations marked by green fluorescent protein-γ-tubulin complex protein2-tagged γ-nucleation complexes (γ-tubulin ring complex), therefore indicating that a large proportion of early polymers was initiated by a noncanonical mechanism not involving γ-tubulin ring complex. Simulation studies indicate that the high rate of noncanonical initiation of new microtubules has the potential to accelerate the rate of array repopulation.
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Affiliation(s)
- Jelmer J Lindeboom
- Laboratory of Cell Biology, Wageningen University, 6708 PB Wageningen, The Netherlands.
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22
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Zhao T, Graham OS, Raposo A, St Johnston D. Growing microtubules push the oocyte nucleus to polarize the Drosophila dorsal-ventral axis. Science 2012; 336:999-1003. [PMID: 22499806 PMCID: PMC3459055 DOI: 10.1126/science.1219147] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The Drosophila dorsal-ventral (DV) axis is polarized when the oocyte nucleus migrates from the posterior to the anterior margin of the oocyte. Prior work suggested that dynein pulls the nucleus to the anterior side along a polarized microtubule cytoskeleton, but this mechanism has not been tested. By imaging live oocytes, we find that the nucleus migrates with a posterior indentation that correlates with its direction of movement. Furthermore, both nuclear movement and the indentation depend on microtubule polymerization from centrosomes behind the nucleus. Thus, the nucleus is not pulled to the anterior but is pushed by the force exerted by growing microtubules. Nuclear migration and DV axis formation therefore depend on centrosome positioning early in oogenesis and are independent of anterior-posterior axis formation.
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Affiliation(s)
- Tongtong Zhao
- The Gurdon Institute and the Department of Genetics, University of Cambridge, Tennis Court Rd, Cambridge CB2 1QN, United Kingdom
| | - Owen S. Graham
- The Department of Engineering, University of Cambridge, Trumpington St, Cambridge, CB2 1PZ, United Kingdom
| | - Alexandre Raposo
- The Gurdon Institute and the Department of Genetics, University of Cambridge, Tennis Court Rd, Cambridge CB2 1QN, United Kingdom
| | - Daniel St Johnston
- The Gurdon Institute and the Department of Genetics, University of Cambridge, Tennis Court Rd, Cambridge CB2 1QN, United Kingdom
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23
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Shi X, Wang J, Yang Y, Ren Y, Zhou J, Li D. Cep70 promotes microtubule assembly in vitro by increasing microtubule elongation. Acta Biochim Biophys Sin (Shanghai) 2012; 44:450-4. [PMID: 22427462 DOI: 10.1093/abbs/gms017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Microtubules are dynamic cytoskeletal polymers present in all eukaryotic cells. In animal cells, they are organized by the centrosome, the major microtubule-organizing center. Many centrosomal proteins act coordinately to modulate microtubule assembly and organization. Our previous work has shown that Cep70, a novel centrosomal protein regulates microtubule assembly and organization in mammalian cells. However, the molecular details remain to be investigated. In this study, we investigated the molecular mechanism of how Cep70 regulates microtubule assembly using purified proteins. Our data showed that Cep70 increased the microtubule length without affecting the microtubule number in the purified system. These results demonstrate that Cep70 could directly regulate microtubule assembly by promoting microtubule elongation instead of microtubule nucleation.
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Affiliation(s)
- Xingjuan Shi
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, China.
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24
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Wu Q, He R, Zhou H, Yu ACH, Zhang B, Teng J, Chen J. Cep57, a NEDD1-binding pericentriolar material component, is essential for spindle pole integrity. Cell Res 2012; 22:1390-401. [PMID: 22508265 DOI: 10.1038/cr.2012.61] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Formation of a bipolar spindle is indispensable for faithful chromosome segregation and cell division. Spindle integrity is largely dependent on the centrosome and the microtubule network. Centrosome protein Cep57 can bundle microtubules in mammalian cells. Its related protein (Cep57R) in Xenopus was characterized as a stabilization factor for microtubule-kinetochore attachment. Here we show that Cep57 is a pericentriolar material (PCM) component. Its interaction with NEDD1 is necessary for the centrosome localization of Cep57. Depletion of Cep57 leads to unaligned chromosomes and a multipolar spindle, which is induced by PCM fragmentation. In the absence of Cep57, centrosome microtubule array assembly activity is weakened, and the spindle length and microtubule density decrease. As a spindle microtubule-binding protein, Cep57 is also responsible for the proper organization of the spindle microtubule and localization of spindle pole focusing proteins. Collectively, these results suggest that Cep57, as a NEDD1-binding centrosome component, could function as a spindle pole- and microtubule-stabilizing factor for establishing robust spindle architecture.
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Affiliation(s)
- Qixi Wu
- The State Key Laboratory of Biomembrane and Membrane Bioengineering and The Key Laboratory of Cell Proliferation and Differentiation of Ministry of Education, College of Life Sciences, Peking University, Beijing 100871, China
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25
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Ribas VT, Gonçalves BS, Linden R, Chiarini LB. Activation of c-Jun N-terminal kinase (JNK) during mitosis in retinal progenitor cells. PLoS One 2012; 7:e34483. [PMID: 22496813 PMCID: PMC3319587 DOI: 10.1371/journal.pone.0034483] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Accepted: 03/05/2012] [Indexed: 01/19/2023] Open
Abstract
Most studies of c-Jun N-terminal Kinase (JNK) activation in retinal tissue were done in the context of neurodegeneration. In this study, we investigated the behavior of JNK during mitosis of progenitor cells in the retina of newborn rats. Retinal explants from newborn rats were kept in vitro for 3 hours and under distinct treatments. Sections of retinal explants or freshly fixed retinal tissue were used to detect JNK phosphorylation by immunohistochemistry, and were examined through both fluorescence and confocal microscopy. Mitotic cells were identified by chromatin morphology, histone-H3 phosphorylation, and location in the retinal tissue. The subcellular localization of proteins was analyzed by double staining with both a DNA marker and an antibody to each protein. Phosphorylation of JNK was also examined by western blot. The results showed that in the retina of newborn rats (P1), JNK is phosphorylated during mitosis of progenitor cells, mainly during the early stages of mitosis. JNK1 and/or JNK2 were preferentially phosphorylated in mitotic cells. Inhibition of JNK induced cell cycle arrest, specifically in mitosis. Treatment with the JNK inhibitor decreased the number of cells in anaphase, but did not alter the number of cells in either prophase/prometaphase or metaphase. Moreover, cells with aberrant chromatin morphology were found after treatment with the JNK inhibitor. The data show, for the first time, that JNK is activated in mitotic progenitor cells of developing retinal tissue, suggesting a new role of JNK in the control of progenitor cell proliferation in the retina.
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Affiliation(s)
| | | | - Rafael Linden
- Instituto de Biofísica Carlos Chagas Filho, UFRJ, Rio de Janeiro, Brasil
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26
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Scharadin TM, Jiang H, Martin S, Eckert RL. TIG3 interaction at the centrosome alters microtubule distribution and centrosome function. J Cell Sci 2012; 125:2604-14. [PMID: 22427689 DOI: 10.1242/jcs.096495] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
TIG3 is an important pro-differentiation regulator that is expressed in the suprabasal epidermis. We have shown that TIG3 activates selective keratinocyte differentiation-associated processes leading to cornified envelope formation. However, TIG3 also suppresses cell proliferation by an unknown mechanism. Our present studies suggest that cessation of growth is mediated through the impact of TIG3 on the centrosome and microtubules. The centrosome regulates microtubule function in interphase cells and microtubule spindle formation in mitotic cells. We show that TIG3 colocalizes with γ-tubulin and pericentrin at the centrosome. Localization of TIG3 at the centrosome alters microtubule nucleation and reduces anterograde microtubule growth, increases acetylation and detyrosination of α-tubulin, increases insoluble tubulin and drives the formation of a peripheral microtubule ring adjacent to the plasma membrane. In addition, TIG3 suppresses centrosome separation, but not duplication, and reduces cell proliferation. We propose that TIG3 regulates the formation of the peripheral microtubule ring observed in keratinocytes of differentiated epidermis and also has a role in the cessation of proliferation in these cells.
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Affiliation(s)
- Tiffany M Scharadin
- Department of Biochemistry, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA
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27
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Teixidó-Travesa N, Roig J, Lüders J. The where, when and how of microtubule nucleation – one ring to rule them all. J Cell Sci 2012; 125:4445-56. [DOI: 10.1242/jcs.106971] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The function of microtubules depends on their arrangement into highly ordered arrays. Spatio-temporal control over the formation of new microtubules and regulation of their properties are central to the organization of these arrays. The nucleation of new microtubules requires γ-tubulin, an essential protein that assembles into multi-subunit complexes and is found in all eukaryotic organisms. However, the way in which γ-tubulin complexes are regulated and how this affects nucleation and, potentially, microtubule behavior, is poorly understood. γ-tubulin has been found in complexes of various sizes but several lines of evidence suggest that only large, ring-shaped complexes function as efficient microtubule nucleators. Human γ-tubulin ring complexes (γTuRCs) are composed of γ-tubulin and the γ-tubulin complex components (GCPs) 2, 3, 4, 5 and 6, which are members of a conserved protein family. Recent work has identified additional unrelated γTuRC subunits, as well as a large number of more transient γTuRC interactors. In this Commentary, we discuss the regulation of γTuRC-dependent microtubule nucleation as a key mechanism of microtubule organization. Specifically, we focus on the regulatory roles of the γTuRC subunits and interactors and present an overview of other mechanisms that regulate γTuRC-dependent microtubule nucleation and organization.
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28
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Nguyen MM, Stone MC, Rolls MM. Microtubules are organized independently of the centrosome in Drosophila neurons. Neural Dev 2011; 6:38. [PMID: 22145670 PMCID: PMC3271965 DOI: 10.1186/1749-8104-6-38] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Accepted: 12/06/2011] [Indexed: 01/26/2023] Open
Abstract
Background The best-studied arrangement of microtubules is that organized by the centrosome, a cloud of microtubule nucleating and anchoring proteins is clustered around centrioles. However, noncentrosomal microtubule arrays are common in many differentiated cells, including neurons. Although microtubules are not anchored at neuronal centrosomes, it remains unclear whether the centrosome plays a role in organizing neuronal microtubules. We use Drosophila as a model system to determine whether centrosomal microtubule nucleation is important in mature neurons. Results In developing and mature neurons, centrioles were not surrounded by the core nucleation protein γ-tubulin. This suggests that the centrioles do not organize functional centrosomes in Drosophila neurons in vivo. Consistent with this idea, centriole position was not correlated with a specific region of the cell body in neurons, and growing microtubules did not cluster around the centriole, even after axon severing when the number of growing plus ends is dramatically increased. To determine whether the centrosome was required for microtubule organization in mature neurons, we used two approaches. First, we used DSas-4 centriole duplication mutants. In these mutants, centrioles were present in many larval sensory neurons, but they were not fully functional. Despite reduced centriole function, microtubule orientation was normal in axons and dendrites. Second, we used laser ablation to eliminate the centriole, and again found that microtubule polarity in axons and dendrites was normal, even 3 days after treatment. Conclusion We conclude that the centrosome is not a major site of microtubule nucleation in Drosophila neurons, and is not required for maintenance of neuronal microtubule organization in these cells.
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Affiliation(s)
- Michelle M Nguyen
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
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29
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Runkle EA, Sundstrom JM, Runkle KB, Liu X, Antonetti DA. Occludin localizes to centrosomes and modifies mitotic entry. J Biol Chem 2011; 286:30847-30858. [PMID: 21757728 DOI: 10.1074/jbc.m111.262857] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Proper control of cell cycle progression and barrier function are essential processes to the maintenance of epithelial cell homeostasis. The contribution of tight junction proteins to barrier function is well established, whereas their contribution to cell cycle control is only beginning to be understood. Centrosomes are the principal microtubule organizing centers in eukaryotic cells and centrosome duplication and separation are linked to the cell cycle and mitotic entry. Here we demonstrate that occludin localizes with centrosomes in Madin-Darby canine kidney cells. Immunocytochemistry and biochemical fractionation studies reveal occludin localizes with centrosomes during interphase and occludin Ser-490 phosphorylation at centrosomes increases with mitotic entry. Stable expression of aspartic acid phosphomimetic (S490D) results in centrosomal localization of occludin and increases cell numbers. Furthermore, we provide evidence that occludin regulates centrosome separation and mitotic entry as the nonphosphorylatable alanine mutation (S490A) impedes centrosome separation, delays mitotic entry, and reduces proliferation. Collectively, these studies demonstrate a novel location and function for occludin in centrosome separation and mitosis.
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Affiliation(s)
- E Aaron Runkle
- Departments of Cellular and Molecular Physiology, Hershey, Pennsylvania 17033
| | - Jeffrey M Sundstrom
- Ophthalmology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033
| | - Kristin B Runkle
- Departments of Cellular and Molecular Physiology, Hershey, Pennsylvania 17033
| | - Xuwen Liu
- University of Michigan Kellogg Eye Center, Ann Arbor, Michigan 48105
| | - David A Antonetti
- University of Michigan Kellogg Eye Center, Ann Arbor, Michigan 48105.
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30
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Holubcová Z, Matula P, Sedláčková M, Vinarský V, Doležalová D, Bárta T, Dvořák P, Hampl A. Human embryonic stem cells suffer from centrosomal amplification. Stem Cells 2011; 29:46-56. [PMID: 20960514 DOI: 10.1002/stem.549] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Propagation of human embryonic stem cells (hESCs) in culture tends to alter karyotype, potentially limiting the prospective use of these cells in patients. The chromosomal instability of some malignancies is considered to be driven, at least in part, by centrosomal overamplification, perturbing balanced chromosome segregation. Here, we report, for the first time, that very high percentage of cultured hESCs has supernumerary centrosomes during mitosis. Supernumerary centrosomes were strictly associated with an undifferentiated hESC state and progressively disappeared on prolonged propagation in culture. Improved attachment to culture substratum and inhibition of CDK2 and Aurora A (key regulators of centrosomal metabolism) diminished the frequency of multicentrosomal mitoses. Thus, both attenuated cell attachment and deregulation of machinery controlling centrosome number contribute to centrosomal overamplification in hESCs. Linking the excessive number of centrosomes in mitoses to the ploidy indicated that both overduplication within a single cell cycle and mitotic failure contributed to generation of numerical centrosomal abnormalities in hESCs. Collectively, our data indicate that supernumerary centrosomes are a significant risk factor for chromosome instability in cultured hESCs and should be evaluated when new culture conditions are being implemented.
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Affiliation(s)
- Zuzana Holubcová
- Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
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31
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Goodwin SS, Vale RD. Patronin regulates the microtubule network by protecting microtubule minus ends. Cell 2010; 143:263-74. [PMID: 20946984 DOI: 10.1016/j.cell.2010.09.022] [Citation(s) in RCA: 187] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2010] [Revised: 07/12/2010] [Accepted: 09/13/2010] [Indexed: 11/18/2022]
Abstract
Tubulin assembles into microtubule polymers that have distinct plus and minus ends. Most microtubule plus ends in living cells are dynamic; the transitions between growth and shrinkage are regulated by assembly-promoting and destabilizing proteins. In contrast, minus ends are generally not dynamic, suggesting their stabilization by some unknown protein. Here, we have identified Patronin (also known as ssp4) as a protein that stabilizes microtubule minus ends in Drosophila S2 cells. In the absence of Patronin, minus ends lose subunits through the actions of the Kinesin-13 microtubule depolymerase, leading to a sparse interphase microtubule array and short, disorganized mitotic spindles. In vitro, the selective binding of purified Patronin to microtubule minus ends is sufficient to protect them against Kinesin-13-induced depolymerization. We propose that Patronin caps and stabilizes microtubule minus ends, an activity that serves a critical role in the organization of the microtubule cytoskeleton.
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Affiliation(s)
- Sarah S Goodwin
- The Howard Hughes Medical Institute and Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158-2200, USA
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32
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Riparbelli MG, Callaini G. Male gametogenesis without centrioles. Dev Biol 2010; 349:427-39. [PMID: 20974123 DOI: 10.1016/j.ydbio.2010.10.021] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2010] [Revised: 10/05/2010] [Accepted: 10/15/2010] [Indexed: 01/08/2023]
Abstract
The orientation of the mitotic spindle plays a central role in specifying stem cell-renewal by enabling interaction of the daughter cells with external cues: the daughter cell closest to the hub region is instructed to self-renew, whereas the distal one starts to differentiate. Here, we have analyzed male gametogenesis in DSas-4 Drosophila mutants and we have reported that spindle alignment and asymmetric divisions are properly executed in male germline stem cells that lack centrioles. Spermatogonial divisions also correctly proceed in the absence of centrioles, giving rise to cysts of 16 primary spermatocytes. By contrast, abnormal meiotic spindles assemble in primary spermatocytes. These results point to different requirements for centrioles during male gametogenesis of Drosophila. Spindle formation during germ cell mitosis may be successfully supported by an acentrosomal pathway that is inadequate to warrant the proper execution of meiosis.
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33
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The insect centriole: A land of discovery. Tissue Cell 2010; 42:69-80. [DOI: 10.1016/j.tice.2010.01.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Revised: 01/11/2010] [Accepted: 01/11/2010] [Indexed: 12/26/2022]
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34
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Biased segregation of DNA and centrosomes: moving together or drifting apart? Nat Rev Mol Cell Biol 2009; 10:804-10. [PMID: 19851338 DOI: 10.1038/nrm2784] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Old and newly synthesized centrosomes have different microtubule nucleating abilities and they contribute to cell polarity when they migrate to opposite poles during cell division. The asymmetric localization of epigenetic marks and kinetochore proteins could lead to the differential recognition of sister chromatids and the biased segregation of DNA strands to daughter cells during cell division. We propose that this asymmetric localization is linked to biased chromatid segregation, which might also be related to the acquisition of distinct cell fates after mitosis.
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35
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Abstract
Asymmetric stem cell division is a mechanism widely employed by the cell to maintain tissue homeostasis, resulting in the production of one stem cell and one differentiating cell. However, asymmetric cell division is not limited to stem cells and is widely observed even in unicellular organisms as well as in cells that make up highly complex tissues. In asymmetric cell division, cells must organize their intracellular components along the axis of asymmetry (sometimes in the context of extracellular architecture). Recent studies have described cell asymmetry in many cell types and in many cases such asymmetry involves the centrosome (or spindle pole body in yeast) as the center of cytoskeleton organization. In this review, I summarize recent discoveries in cellular polarity that lead to an asymmetric outcome, with a focus on centrosome function.
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Affiliation(s)
- Yukiko M Yamashita
- Life Sciences Institute, Center for Stem Cell Biology, Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109-2216, USA.
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