1
|
Tarasovetc EV, Sissoko GB, Mukhina AS, Maiorov A, Ataullakhanov FI, Cheeseman IM, Grishchuk EL. Molecular density-accelerated binding-site maturation underlies CENP-T-dependent kinetochore assembly. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.25.581584. [PMID: 38464265 PMCID: PMC10925139 DOI: 10.1101/2024.02.25.581584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Formation of macromolecular cellular structures relies on recruitment of multiple proteins, requiring the precisely controlled pairwise binding interactions. At human kinetochores, our recent work found that the high molecular density environment enables strong bonding between the Ndc80 complex and its two binding sites at the CENP-T receptor. However, the mechanistic basis for this unusual density-dependent facilitation remains unknown. Here, using quantitative single-molecule approaches, we reveal two distinct mechanisms that drive preferential recruitment of the Ndc80 complex to higher-order structures of CENP-T, as opposed to CENP-T monomers. First, the Ndc80 binding sites within the disordered tail of the CENP-T mature over time, leading to a stronger grip on the Spc24/25 heads of the Ndc80 complexes. Second, the maturation of Ndc80 binding sites is accelerated when CENP-T molecules are clustered in close proximity. The rates of the clustering-induced maturation are remarkably different for two binding sites within CENP-T, correlating with different interfaces formed by the corresponding CENP-T sequences as they wrap around the Spc24/25 heads. The differential clustering-dependent regulation of these sites is preserved in dividing human cells, suggesting a distinct regulatory entry point to control kinetochore-microtubule interactions. The tunable acceleration of slowly maturing binding sites by a high molecular-density environment may represent a fundamental physicochemical mechanism to assist the assembly of mitotic kinetochores and other macromolecular structures.
Collapse
Affiliation(s)
- Ekaterina V. Tarasovetc
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania; Philadelphia, PA 19104, USA
| | - Gunter B. Sissoko
- Whitehead Institute for Biomedical Research; Cambridge, MA 02142, USA
- Department of Biology, Massachusetts Institute of Technology; Cambridge, MA 02142, USA
| | - Anna S. Mukhina
- Department of Physics, Lomonosov Moscow State University; Moscow, 119991, Russia
| | - Aleksandr Maiorov
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania; Philadelphia, PA 19104, USA
| | - Fazoil I. Ataullakhanov
- Center for Theoretical Problems of Physicochemical Pharmacology, Russian Academy of Sciences; Moscow, 119991, Russia
- Dmitry Rogachev National Research Center of Pediatric Hematology, Oncology and Immunology; Moscow, 117198, Russia
- Moscow Institute of Physics and Technology; 141701, Dolgoprudny, Russia
| | - Iain M. Cheeseman
- Whitehead Institute for Biomedical Research; Cambridge, MA 02142, USA
- Department of Biology, Massachusetts Institute of Technology; Cambridge, MA 02142, USA
| | - Ekaterina L. Grishchuk
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania; Philadelphia, PA 19104, USA
| |
Collapse
|
2
|
Edgerton HD, Mukherjee S, Johansson M, Bachant J, Gardner MK, Clarke DJ. Low tension recruits the yeast Aurora B protein Ipl1 to centromeres in metaphase. J Cell Sci 2023; 136:jcs261416. [PMID: 37519149 PMCID: PMC10445749 DOI: 10.1242/jcs.261416] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Accepted: 07/26/2023] [Indexed: 08/01/2023] Open
Abstract
Accurate genome segregation in mitosis requires that all chromosomes are bioriented on the spindle. Cells monitor biorientation by sensing tension across sister centromeres. Chromosomes that are not bioriented have low centromere tension, which allows Aurora B (yeast Ipl1) to perform error correction that locally loosens kinetochore-microtubule attachments to allow detachment of microtubules and fresh attempts at achieving biorientation. However, it is not known whether low tension recruits Aurora B to centromeres or, alternatively, whether low tension directly activates Aurora B already localized at centromeres. In this work, we experimentally induced low tension in metaphase Saccharomyces cerevisiae yeast cells, then monitored Ipl1 localization. We find low tension recruits Ipl1 to centromeres. Furthermore, low tension-induced Ipl1 recruitment depended on Bub1, which is known to provide a binding site for Ipl1. In contrast, Top2, which can also recruit Ipl1 to centromeres, was not required. Our results demonstrate cells are sensitive to low tension at centromeres and respond by actively recruiting Ip1l for error correction.
Collapse
Affiliation(s)
- Heather D. Edgerton
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Soumya Mukherjee
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Marnie Johansson
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Jeff Bachant
- Department of Molecular Cell Systems Biology, University of California, Riverside, Riverside, CA 92521, USA
| | - Melissa K. Gardner
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Duncan J. Clarke
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, MN 55455, USA
| |
Collapse
|
3
|
Yatskevich S, Barford D, Muir KW. Conserved and divergent mechanisms of inner kinetochore assembly onto centromeric chromatin. Curr Opin Struct Biol 2023; 81:102638. [PMID: 37343495 DOI: 10.1016/j.sbi.2023.102638] [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: 02/09/2023] [Revised: 05/03/2023] [Accepted: 05/23/2023] [Indexed: 06/23/2023]
Abstract
Kinetochores are large protein complexes built on centromeric chromatin that mediate chromosome segregation. The inner kinetochore, or constitutive centromere-associated network (CCAN), assembles onto centromeres defined by centromere protein A (CENP-A) nucleosomes (CENP-ANuc), and acts as a platform for the regulated assembly of the microtubule-binding outer kinetochore. Recent cryo-EM work revealed structural conservation of CCAN, from the repeating human regional centromeres to the point centromere of budding yeast. Centromere recognition is determined mainly through engagement of duplex DNA proximal to the CENP-A nucleosome by a DNA-binding CENP-LN channel located at the core of CCAN. Additional DNA interactions formed by other CCAN modules create an enclosed DNA-binding chamber. This configuration explains how kinetochores maintain their tight grip on centromeric DNA to withstand the forces of chromosome segregation. Defining the higher-order architecture of complete kinetochore assemblies with implications for understanding the 3D organisation of regional centromeres and mechanisms of kinetochore dynamics, including how kinetochores sense and respond to tension, are important future directions.
Collapse
Affiliation(s)
- Stanislau Yatskevich
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, United Kingdom. https://twitter.com/StanislauY
| | - David Barford
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, United Kingdom.
| | - Kyle W Muir
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, United Kingdom. https://twitter.com/centromuir
| |
Collapse
|
4
|
Hara M, Ariyoshi M, Sano T, Nozawa RS, Shinkai S, Onami S, Jansen I, Hirota T, Fukagawa T. Centromere/kinetochore is assembled through CENP-C oligomerization. Mol Cell 2023:S1097-2765(23)00379-9. [PMID: 37295434 DOI: 10.1016/j.molcel.2023.05.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 04/04/2023] [Accepted: 05/16/2023] [Indexed: 06/12/2023]
Abstract
Kinetochore is an essential protein complex required for accurate chromosome segregation. The constitutive centromere-associated network (CCAN), a subcomplex of the kinetochore, associates with centromeric chromatin and provides a platform for the kinetochore assembly. The CCAN protein CENP-C is thought to be a central hub for the centromere/kinetochore organization. However, the role of CENP-C in CCAN assembly needs to be elucidated. Here, we demonstrate that both the CCAN-binding domain and the C-terminal region that includes the Cupin domain of CENP-C are necessary and sufficient for chicken CENP-C function. Structural and biochemical analyses reveal self-oligomerization of the Cupin domains of chicken and human CENP-C. We find that the CENP-C Cupin domain oligomerization is vital for CENP-C function, centromeric localization of CCAN, and centromeric chromatin organization. These results suggest that CENP-C facilitates the centromere/kinetochore assembly through its oligomerization.
Collapse
Affiliation(s)
- Masatoshi Hara
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan.
| | - Mariko Ariyoshi
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
| | - Tomoki Sano
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
| | - Ryu-Suke Nozawa
- Division of Experimental Pathology, Cancer Institute of the Japanese Foundation for Cancer Research, Tokyo 135-8550, Japan
| | - Soya Shinkai
- Laboratory for Developmental Dynamics, RIKEN Center for Biosystems Dynamics Research, Kobe 650-0047, Japan
| | - Shuichi Onami
- Laboratory for Developmental Dynamics, RIKEN Center for Biosystems Dynamics Research, Kobe 650-0047, Japan
| | | | - Toru Hirota
- Division of Experimental Pathology, Cancer Institute of the Japanese Foundation for Cancer Research, Tokyo 135-8550, Japan
| | - Tatsuo Fukagawa
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan.
| |
Collapse
|
5
|
Bunning AR, Gupta Jr. ML. The importance of microtubule-dependent tension in accurate chromosome segregation. Front Cell Dev Biol 2023; 11:1096333. [PMID: 36755973 PMCID: PMC9899852 DOI: 10.3389/fcell.2023.1096333] [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: 11/12/2022] [Accepted: 01/11/2023] [Indexed: 01/24/2023] Open
Abstract
Accurate chromosome segregation is vital for cell and organismal viability. The mitotic spindle, a bipolar macromolecular machine composed largely of dynamic microtubules, is responsible for chromosome segregation during each cell replication cycle. Prior to anaphase, a bipolar metaphase spindle must be formed in which each pair of chromatids is attached to microtubules from opposite spindle poles. In this bipolar configuration pulling forces from the dynamic microtubules can generate tension across the sister kinetochores. The tension status acts as a signal that can destabilize aberrant kinetochore-microtubule attachments and reinforces correct, bipolar connections. Historically it has been challenging to isolate the specific role of tension in mitotic processes due to the interdependency of attachment and tension status at kinetochores. Recent technical and experimental advances have revealed new insights into how tension functions during mitosis. Here we summarize the evidence that tension serves as a biophysical signal that unifies multiple aspects of kinetochore and centromere function to ensure accurate chromosome segregation.
Collapse
|
6
|
Sridhar S, Fukagawa T. Kinetochore Architecture Employs Diverse Linker Strategies Across Evolution. Front Cell Dev Biol 2022; 10:862637. [PMID: 35800888 PMCID: PMC9252888 DOI: 10.3389/fcell.2022.862637] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 05/23/2022] [Indexed: 01/09/2023] Open
Abstract
The assembly of a functional kinetochore on centromeric chromatin is necessary to connect chromosomes to the mitotic spindle, ensuring accurate chromosome segregation. This connecting function of the kinetochore presents multiple internal and external structural challenges. A microtubule interacting outer kinetochore and centromeric chromatin interacting inner kinetochore effectively confront forces from the external spindle and centromere, respectively. While internally, special inner kinetochore proteins, defined as “linkers,” simultaneously interact with centromeric chromatin and the outer kinetochore to enable association with the mitotic spindle. With the ability to simultaneously interact with outer kinetochore components and centromeric chromatin, linker proteins such as centromere protein (CENP)-C or CENP-T in vertebrates and, additionally CENP-QOkp1-UAme1 in yeasts, also perform the function of force propagation within the kinetochore. Recent efforts have revealed an array of linker pathways strategies to effectively recruit the largely conserved outer kinetochore. In this review, we examine these linkages used to propagate force and recruit the outer kinetochore across evolution. Further, we look at their known regulatory pathways and implications on kinetochore structural diversity and plasticity.
Collapse
|
7
|
Abstract
Microtubule attachments to kinetochores cause their deformation - a murky phenomenon known as intra-kinetochore stretching. A new study proposes that intra-kinetochore stretching is independent of microtubule-pulling forces and mediates efficient spindle assembly checkpoint silencing to prevent chromosomal instability.
Collapse
|
8
|
Uchida KSK, Jo M, Nagasaka K, Takahashi M, Shindo N, Shibata K, Tanaka K, Masumoto H, Fukagawa T, Hirota T. Kinetochore stretching-mediated rapid silencing of the spindle-assembly checkpoint required for failsafe chromosome segregation. Curr Biol 2021; 31:1581-1591.e3. [PMID: 33651990 DOI: 10.1016/j.cub.2021.01.062] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 11/20/2020] [Accepted: 01/19/2021] [Indexed: 11/15/2022]
Abstract
The spindle-assembly checkpoint facilitates mitotic fidelity by delaying anaphase onset in response to microtubule vacancy at kinetochores. Following microtubule attachment, kinetochores receive microtubule-derived force, which causes kinetochores to undergo repetitive cycles of deformation; this phenomenon is referred to as kinetochore stretching. The nature of the forces and the relevance relating this deformation are not well understood. Here, we show that kinetochore stretching occurs within a framework of single end-on attached kinetochores, irrespective of microtubule poleward pulling force. An experimental method to conditionally interfere with the stretching allowed us to determine that kinetochore stretching comprises an essential process of checkpoint silencing by promoting PP1 phosphatase recruitment after the establishment of end-on attachments and removal of the majority of checkpoint-activating kinase Mps1 from kinetochores. Remarkably, we found that a lower frequency of kinetochore stretching largely correlates with a prolonged metaphase in cancer cell lines with chromosomal instability. Perturbation of kinetochore stretching and checkpoint silencing in chromosomally stable cells produced anaphase bridges, which can be alleviated by reducing chromosome-loaded cohesin. These observations indicate that kinetochore stretching-mediated checkpoint silencing provides an unanticipated etiology underlying chromosomal instability and underscores the importance of a rapid metaphase-to-anaphase transition in sustaining mitotic fidelity.
Collapse
Affiliation(s)
- Kazuhiko S K Uchida
- Division of Experimental Pathology, Cancer Institute of the Japanese Foundation for Cancer Research, Tokyo, Japan; Division of Functional Genomics, Faculty of Pharmaceutical Sciences, Himeji Dokkyo University, Himeji, Japan
| | - Minji Jo
- Division of Experimental Pathology, Cancer Institute of the Japanese Foundation for Cancer Research, Tokyo, Japan
| | - Kota Nagasaka
- Division of Experimental Pathology, Cancer Institute of the Japanese Foundation for Cancer Research, Tokyo, Japan
| | - Motoko Takahashi
- Division of Experimental Pathology, Cancer Institute of the Japanese Foundation for Cancer Research, Tokyo, Japan
| | - Norihisa Shindo
- Division of Experimental Pathology, Cancer Institute of the Japanese Foundation for Cancer Research, Tokyo, Japan
| | - Katsushi Shibata
- Division of Functional Genomics, Faculty of Pharmaceutical Sciences, Himeji Dokkyo University, Himeji, Japan
| | - Kozo Tanaka
- Department of Molecular Oncology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Hiroshi Masumoto
- Laboratory of Chromosome Engineering, Kazusa DNA Research Institute, Kisarazu, Japan
| | - Tatsuo Fukagawa
- Laboratory of Chromosome Biology, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
| | - Toru Hirota
- Division of Experimental Pathology, Cancer Institute of the Japanese Foundation for Cancer Research, Tokyo, Japan.
| |
Collapse
|
9
|
Renda F, Magidson V, Tikhonenko I, Fisher R, Miles C, Mogilner A, Khodjakov A. Effects of malleable kinetochore morphology on measurements of intrakinetochore tension. Open Biol 2020; 10:200101. [PMID: 32634373 PMCID: PMC7571466 DOI: 10.1098/rsob.200101] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The distance between fluorescent spots formed by various kinetochore proteins (delta) is commonly interpreted as a manifestation of intrakinetochore tension (IKT) caused by microtubule-mediated forces. However, large-scale changes of the kinetochore architecture (such as its shape or dimensions) may also contribute to the value of delta. To assess contributions of these non-elastic changes, we compare behaviour of delta values in human kinetochores with small yet mechanically malleable kinetochores against compound kinetochores in Indian muntjac (IM) cells whose architecture remains constant. Due to the micrometre-scale length of kinetochore plates in IM, their shape and orientation are discernible in conventional light microscopy, which enables precise measurements of IKT independent of contributions from changes in overall architecture of the organelle. We find that delta in IM kinetochores remains relatively constant when microtubule-mediated forces are suppressed by Taxol, but it prominently decreases upon detachment of microtubules. By contrast, large decreases of delta observed in Taxol-treated human cells coincide with prominent changes in length and curvature of the kinetochore plate. These observations, supported by computational modelling, suggest that at least 50% of the decrease in delta in human cells reflects malleable reorganization of kinetochore architecture rather than elastic recoil due to IKT.
Collapse
Affiliation(s)
- Fioranna Renda
- New York State Department of Health, Wadsworth Center, Albany, NY, USA
| | - Valentin Magidson
- New York State Department of Health, Wadsworth Center, Albany, NY, USA
| | - Irina Tikhonenko
- New York State Department of Health, Wadsworth Center, Albany, NY, USA
| | - Rebecca Fisher
- New York State Department of Health, Wadsworth Center, Albany, NY, USA
| | - Christopher Miles
- Courant Institute and Department of Biology, New York University, New York, NY, USA
| | - Alex Mogilner
- Courant Institute and Department of Biology, New York University, New York, NY, USA
| | - Alexey Khodjakov
- New York State Department of Health, Wadsworth Center, Albany, NY, USA.,Rensselaer Polytechnic Institute, Troy, NY, USA
| |
Collapse
|
10
|
Roscioli E, Germanova TE, Smith CA, Embacher PA, Erent M, Thompson AI, Burroughs NJ, McAinsh AD. Ensemble-Level Organization of Human Kinetochores and Evidence for Distinct Tension and Attachment Sensors. Cell Rep 2020; 31:107535. [PMID: 32348762 PMCID: PMC7196887 DOI: 10.1016/j.celrep.2020.107535] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 02/10/2020] [Accepted: 03/27/2020] [Indexed: 12/13/2022] Open
Abstract
Kinetochores are multi-protein machines that form dynamic attachments to microtubules and control chromosome segregation. High fidelity is ensured because kinetochores can monitor attachment status and tension, using this information to activate checkpoints and error-correction mechanisms. To explore how kinetochores achieve this, we used two- and three-color subpixel fluorescence localization to define how proteins from six major complexes (CCAN, MIS12, NDC80, KNL1, RZZ, and SKA) and the checkpoint proteins Bub1, Mad1, and Mad2 are organized in the human kinetochore. This reveals how the outer kinetochore has a high nematic order and is largely invariant to the loss of attachment or tension, except for two mechanical sensors. First, Knl1 unravels to relay tension, and second, NDC80 undergoes jackknifing and loss of nematic order under microtubule detachment, with only the latter wired up to the checkpoint signaling system. This provides insight into how kinetochores integrate mechanical signals to promote error-free chromosome segregation.
Collapse
Affiliation(s)
- Emanuele Roscioli
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK; Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK
| | - Tsvetelina E Germanova
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK; Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK
| | - Christopher A Smith
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK; Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK
| | - Peter A Embacher
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK; Mathematics Institute, University of Warwick, Coventry, UK
| | - Muriel Erent
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK; Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK
| | - Amelia I Thompson
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK; Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK
| | - Nigel J Burroughs
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK; Mathematics Institute, University of Warwick, Coventry, UK.
| | - Andrew D McAinsh
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK; Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK.
| |
Collapse
|
11
|
Wang Y, Li J, Dong F, Yue W, Ouyang YC, Wang ZB, Hou Y, Schatten H, Sun QY. CENP-T regulates both the G2/M transition and anaphase entry by acting through CDH1 in meiotic oocytes. J Cell Sci 2020; 133:jcs238105. [PMID: 31964702 DOI: 10.1242/jcs.238105] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 12/31/2019] [Indexed: 12/18/2022] Open
Abstract
Oocyte meiotic maturation failure is one of the major causes for female infertility. Meiotic resumption (the G2/M transition) and progression through metaphase I (MI) are two critical stages of oocyte meiotic maturation. Here, we report that centromere protein T (CENP-T), an internal kinetochore protein, plays a critical role in meiotic resumption of mouse oocytes. Depletion of CENP-T by siRNA injection increased the CDH1 (also known as FZR1) level, resulting in increased activity of the anaphase-promoting complex (APC)-CDH1 complex, and further leading to decreased levels of the cyclin protein CCNB1, attenuated maturation-promoting factor (MPF) activity, and finally severely compromised meiotic resumption. The impaired meiotic resumption caused by CENP-T depletion could be rescued by overexpression of exogenous CCNB1 or knockdown of endogenous CDH1. Overexpression of exogenous CENP-T resulted in decreased CDH1 levels, which accelerated the progression of G2/M transition, and accelerated meiotic cell cycle progression after germinal vesicle breakdown (GVBD). Unexpectedly, spindle organization after GVBD was not affected by the overexpression, but the distribution of chromosomes was affected. Our findings reveal a novel role for CENP-T in regulating meiotic progression by acting through CDH1.
Collapse
Affiliation(s)
- Yue Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jian Li
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- Department of Reproductive Medicine, Peking University Shenzhen Hospital, Shenzhen Peking University The Hong Kong University of Science and Technology Medical Center, Shenzhen 518036, China
| | - Feng Dong
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Wei Yue
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ying-Chun Ouyang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhen-Bo Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yi Hou
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Heide Schatten
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MI 65211, USA
| | - Qing-Yuan Sun
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|
12
|
Multiple phosphorylations control recruitment of the KMN network onto kinetochores. Nat Cell Biol 2018; 20:1378-1388. [PMID: 30420662 DOI: 10.1038/s41556-018-0230-0] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Accepted: 10/08/2018] [Indexed: 11/08/2022]
Abstract
To establish a functional kinetochore, the constitutive centromere-associated network (CCAN) forms a foundation on the centromere and recruits the KMN network, which directly binds to spindle microtubules. The CENP-C and CENP-T pathways in the CCAN recruit the KMN network to kinetochores, independently. The CENP-C pathway has been considered the major scaffold for the KMN network in vertebrate CCAN. However, we demonstrate that it is mainly the CENP-T pathway that recruits the KMN network onto the kinetochores and that CENP-T-KMN interactions are essential in chicken DT40 cells. By contrast, less Ndc80 binds to the CENP-C pathway in mitosis and the Mis12-CENP-C association is decreased during mitotic progression, which is consistent with the finding that the Mis12 complex-CENP-C binding is dispensable for cell viability. Furthermore, we find that multiple phosphoregulations of CENP-T and the Mis12 complex make the CENP-T pathway dominant. These results provide key insights into kinetochore dynamics during mitotic progression.
Collapse
|
13
|
Suzuki A, Long SK, Salmon ED. An optimized method for 3D fluorescence co-localization applied to human kinetochore protein architecture. eLife 2018; 7:32418. [PMID: 29323636 PMCID: PMC5764572 DOI: 10.7554/elife.32418] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Accepted: 12/22/2017] [Indexed: 12/13/2022] Open
Abstract
Two-color fluorescence co-localization in 3D (three-dimension) has the potential to achieve accurate measurements at the nanometer length scale. Here, we optimized a 3D fluorescence co-localization method that uses mean values for chromatic aberration correction to yield the mean separation with ~10 nm accuracy between green and red fluorescently labeled protein epitopes within single human kinetochores. Accuracy depended critically on achieving small standard deviations in fluorescence centroid determination, chromatic aberration across the measurement field, and coverslip thickness. Computer simulations showed that large standard deviations in these parameters significantly increase 3D measurements from their true values. Our 3D results show that at metaphase, the protein linkage between CENP-A within the inner kinetochore and the microtubule-binding domain of the Ndc80 complex within the outer kinetochore is on average ~90 nm. The Ndc80 complex appears fully extended at metaphase and exhibits the same subunit structure in vivo as found in vitro by crystallography.
Collapse
Affiliation(s)
- Aussie Suzuki
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, United States
| | - Sarah K Long
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, United States
| | - Edward D Salmon
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, United States
| |
Collapse
|
14
|
Hung CY, Volkmar B, Baker JD, Bauer JW, Gussoni E, Hainzl S, Klausegger A, Lorenzo J, Mihalek I, Rittinger O, Tekin M, Dallman JE, Bodamer OA. A defect in the inner kinetochore protein CENPT causes a new syndrome of severe growth failure. PLoS One 2017; 12:e0189324. [PMID: 29228025 PMCID: PMC5724856 DOI: 10.1371/journal.pone.0189324] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 11/23/2017] [Indexed: 11/18/2022] Open
Abstract
Primordial growth failure has been linked to defects in the biology of cell division and replication. The complex processes involved in microtubule spindle formation, organization and function have emerged as a dominant patho-mechanism in these conditions. The majority of reported disease genes encode for centrosome and centriole proteins, leaving kinetochore proteins by which the spindle apparatus interacts with the chromosomes largely unaccounted for. We report a novel disease gene encoding the constitutive inner kinetochore member CENPT, which is involved in kinetochore targeting and assembly, resulting in severe growth failure in two siblings of a consanguineous family. We herein present studies on the molecular and cellular mechanisms that explain how genetic mutations in this gene lead to primordial growth failure. In both, affected human cell lines and a zebrafish knock-down model of Cenpt, we observed aberrations in cell division with abnormal accumulation of micronuclei and of nuclei with increased DNA content arising from incomplete and/or irregular chromosomal segregation. Our studies underscore the critical importance of kinetochore function for overall body growth and provide new insight into the cellular mechanisms implicated in the spectrum of these severe growth disorders.
Collapse
Affiliation(s)
- Christina Y. Hung
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
| | - Barbara Volkmar
- Department of Pediatrics, Paracelsus Medical University Salzburg, Salzburg, Austria
| | - James D. Baker
- Department of Biology, University of Miami, Coral Gables, Florida, United States of America
| | - Johann W. Bauer
- Department of Dermatology, EB House Austria, University Hospital of the Paracelsus Medical University Salzburg, Salzburg, Austria
| | - Emanuela Gussoni
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
| | - Stefan Hainzl
- Department of Dermatology, EB House Austria, University Hospital of the Paracelsus Medical University Salzburg, Salzburg, Austria
| | - Alfred Klausegger
- Department of Dermatology, EB House Austria, University Hospital of the Paracelsus Medical University Salzburg, Salzburg, Austria
| | - Jose Lorenzo
- John P. Hussman Institute for Human Genomics, University of Miami, Miami, Florida, United States of America
| | - Ivana Mihalek
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, Massachusetts, United States of America
| | - Olaf Rittinger
- Department of Pediatrics, Paracelsus Medical University Salzburg, Salzburg, Austria
| | - Mustafa Tekin
- John P. Hussman Institute for Human Genomics, University of Miami, Miami, Florida, United States of America
| | - Julia E. Dallman
- Department of Biology, University of Miami, Coral Gables, Florida, United States of America
| | - Olaf A. Bodamer
- Division of Genetics and Genomics, Boston Children’s Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
| |
Collapse
|
15
|
Haase J, Bonner MK, Halas H, Kelly AE. Distinct Roles of the Chromosomal Passenger Complex in the Detection of and Response to Errors in Kinetochore-Microtubule Attachment. Dev Cell 2017; 42:640-654.e5. [PMID: 28950102 DOI: 10.1016/j.devcel.2017.08.022] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 07/21/2017] [Accepted: 08/26/2017] [Indexed: 01/22/2023]
Abstract
The chromosomal passenger complex (CPC) localizes to centromeres in early mitosis to activate its subunit Aurora B kinase. However, it is unclear whether centromeric CPC localization contributes to CPC functions beyond Aurora B activation. Here, we show that an activated CPC that cannot localize to centromeres supports functional assembly of the outer kinetochore but is unable to correct errors in kinetochore-microtubule attachment in Xenopus egg extracts. We find that CPC has two distinct roles at centromeres: one to selectively phosphorylate Ndc80 to regulate attachment and a second, conserved kinase-independent role in the proper composition of inner kinetochore proteins. Although a fully assembled inner kinetochore is not required for outer kinetochore assembly, we find it is essential to recruit tension indicators, such as BubR1 and 3F3/2, to erroneous attachments. We conclude centromeric CPC is necessary for tension-dependent removal of erroneous attachments and for the kinetochore composition required to detect tension loss.
Collapse
Affiliation(s)
- Julian Haase
- Laboratory of Biochemistry & Molecular Biology, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Mary Kate Bonner
- Laboratory of Biochemistry & Molecular Biology, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Hyunmi Halas
- Laboratory of Biochemistry & Molecular Biology, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Alexander E Kelly
- Laboratory of Biochemistry & Molecular Biology, National Cancer Institute, NIH, Bethesda, MD 20892, USA.
| |
Collapse
|
16
|
Renda F, Pellacani C, Strunov A, Bucciarelli E, Naim V, Bosso G, Kiseleva E, Bonaccorsi S, Sharp DJ, Khodjakov A, Gatti M, Somma MP. The Drosophila orthologue of the INT6 onco-protein regulates mitotic microtubule growth and kinetochore structure. PLoS Genet 2017; 13:e1006784. [PMID: 28505193 PMCID: PMC5448806 DOI: 10.1371/journal.pgen.1006784] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 05/30/2017] [Accepted: 04/27/2017] [Indexed: 12/01/2022] Open
Abstract
INT6/eIF3e is a highly conserved component of the translation initiation complex that interacts with both the 26S proteasome and the COP9 signalosome, two complexes implicated in ubiquitin-mediated protein degradation. The INT6 gene was originally identified as the insertion site of the mouse mammary tumor virus (MMTV), and later shown to be involved in human tumorigenesis. Here we show that depletion of the Drosophila orthologue of INT6 (Int6) results in short mitotic spindles and deformed centromeres and kinetochores with low intra-kinetochore distance. Poleward flux of microtubule subunits during metaphase is reduced, although fluorescence recovery after photobleaching (FRAP) demonstrates that microtubules remain dynamic both near the kinetochores and at spindle poles. Mitotic progression is delayed during metaphase due to the activity of the spindle assembly checkpoint (SAC). Interestingly, a deubiquitinated form of the kinesin Klp67A (a putative orthologue of human Kif18A) accumulates near the kinetochores in Int6-depleted cells. Consistent with this finding, Klp67A overexpression mimics the Int6 RNAi phenotype. Furthermore, simultaneous depletion of Int6 and Klp67A results in a phenotype identical to RNAi of just Klp67A, which indicates that Klp67A deficiency is epistatic over Int6 deficiency. We propose that Int6-mediated ubiquitination is required to control the activity of Klp67A. In the absence of this control, excess of Klp67A at the kinetochore suppresses microtubule plus-end polymerization, which in turn results in reduced microtubule flux, spindle shortening, and centromere/kinetochore deformation. INT6 is an evolutionarily conserved gene originally identified as the insertion site of the mouse mammary tumor virus that causes tumors in mice. INT6 is downregulated in many human cancers, suggesting that it acts as tumor suppressor gene. The INT6 protein is involved in several biological processes, including translation and ubiquitin-mediated protein degradation. We performed RNA interference (RNAi) against the Drosophila homologue of INT6 (Int6) and analyzed the effects of Int6 depletion on mitotic cell division. We found that loss of Int6 results in short spindles, delayed progression though metaphase and abnormally shaped centromeres/kinetochores. We also found that Int6-depleted cells fail to degrade the kinesin Klp67A. This protein, known to attenuate polymerization of microtubule (MTs) plus ends, accumulated at the kinetochores in Int6-depleted cells. We propose that this condition affects MT growth at the kinetochore, which in turn results in centromere/kinetochore deformation and delays satisfaction of the mitotic checkpoint.
Collapse
Affiliation(s)
- Fioranna Renda
- Dipartimento di Biologia e Biotecnologie “C. Darwin”, Sapienza, Università di Roma, Roma, Italy
- Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Claudia Pellacani
- Dipartimento di Biologia e Biotecnologie “C. Darwin”, Sapienza, Università di Roma, Roma, Italy
- Istituto di Biologia e Patologia Molecolari (IBPM) del CNR, Roma, Italy
| | - Anton Strunov
- Institute of Molecular and Cellular Biology, Siberian Branch of RAS, Novosibirsk, Russia
- Institute of Cytology and Genetics, Siberian Branch of RAS, Novosibirsk, Russia
| | | | - Valeria Naim
- Dipartimento di Biologia e Biotecnologie “C. Darwin”, Sapienza, Università di Roma, Roma, Italy
| | - Giuseppe Bosso
- Dipartimento di Biologia e Biotecnologie “C. Darwin”, Sapienza, Università di Roma, Roma, Italy
| | - Elena Kiseleva
- Institute of Molecular and Cellular Biology, Siberian Branch of RAS, Novosibirsk, Russia
- Institute of Cytology and Genetics, Siberian Branch of RAS, Novosibirsk, Russia
| | - Silvia Bonaccorsi
- Dipartimento di Biologia e Biotecnologie “C. Darwin”, Sapienza, Università di Roma, Roma, Italy
| | - David J. Sharp
- Department of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Alexey Khodjakov
- Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Maurizio Gatti
- Dipartimento di Biologia e Biotecnologie “C. Darwin”, Sapienza, Università di Roma, Roma, Italy
- Istituto di Biologia e Patologia Molecolari (IBPM) del CNR, Roma, Italy
- Institute of Molecular and Cellular Biology, Siberian Branch of RAS, Novosibirsk, Russia
- * E-mail: (MPS); (MG)
| | - Maria Patrizia Somma
- Istituto di Biologia e Patologia Molecolari (IBPM) del CNR, Roma, Italy
- * E-mail: (MPS); (MG)
| |
Collapse
|
17
|
Stepwise unfolding supports a subunit model for vertebrate kinetochores. Proc Natl Acad Sci U S A 2017; 114:3133-3138. [PMID: 28265097 DOI: 10.1073/pnas.1614145114] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
During cell division, interactions between microtubules and chromosomes are mediated by the kinetochore, a proteinaceous structure located at the primary constriction of chromosomes. In addition to the centromere histone centromere protein A (CENP-A), 15 other members of the constitutive centromere associated network (CCAN) participate in the formation of a chromatin-associated scaffold that supports kinetochore structure. We performed a targeted screen analyzing unfolded centrochromatin from CENP-depleted chromosomes. Our results revealed that CENP-C and CENP-S are critical for the stable folding of mitotic kinetochore chromatin. Multipeak fitting algorithms revealed the presence of an organized pattern of centrochromatin packing consistent with arrangement of CENP-A-containing nucleosomes into up to five chromatin "subunits"-each containing roughly 20-30 nucleosomes. These subunits could be either layers of a boustrophedon or small loops of centromeric chromatin.
Collapse
|
18
|
Hara M, Fukagawa T. Critical Foundation of the Kinetochore: The Constitutive Centromere-Associated Network (CCAN). PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2017; 56:29-57. [PMID: 28840232 DOI: 10.1007/978-3-319-58592-5_2] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The kinetochore is a large protein complex, which is assembled at the centromere of a chromosome to ensure faithful chromosome segregation during M-phase. The centromere in most eukaryotes is epigenetically specified by DNA sequence-independent mechanisms. The constitutive centromere-associated network (CCAN) is a subcomplex in the kinetochore that localizes to the centromere throughout the cell cycle. The CCAN has interfaces bound to the centromeric chromatin and the spindle microtubule-binding complex; therefore, it functions as a foundation of kinetochore formation. Here, we summarize recent progress in our understanding of the structure and organization of the CCAN. We also discuss an additional role of the CCAN in the maintenance of centromere position and dynamic reorganization of the CCAN.
Collapse
Affiliation(s)
- Masatoshi Hara
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Tatsuo Fukagawa
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, 565-0871, Japan.
| |
Collapse
|
19
|
Huis In 't Veld PJ, Jeganathan S, Petrovic A, Singh P, John J, Krenn V, Weissmann F, Bange T, Musacchio A. Molecular basis of outer kinetochore assembly on CENP-T. eLife 2016; 5. [PMID: 28012276 PMCID: PMC5241120 DOI: 10.7554/elife.21007] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 12/23/2016] [Indexed: 12/23/2022] Open
Abstract
Stable kinetochore-microtubule attachment is essential for cell division. It requires recruitment of outer kinetochore microtubule binders by centromere proteins C and T (CENP-C and CENP-T). To study the molecular requirements of kinetochore formation, we reconstituted the binding of the MIS12 and NDC80 outer kinetochore subcomplexes to CENP-C and CENP-T. Whereas CENP-C recruits a single MIS12:NDC80 complex, we show here that CENP-T binds one MIS12:NDC80 and two NDC80 complexes upon phosphorylation by the mitotic CDK1:Cyclin B complex at three distinct CENP-T sites. Visualization of reconstituted complexes by electron microscopy supports this model. Binding of CENP-C and CENP-T to MIS12 is competitive, and therefore CENP-C and CENP-T act in parallel to recruit two MIS12 and up to four NDC80 complexes. Our observations provide a molecular explanation for the stoichiometry of kinetochore components and its cell cycle regulation, and highlight how outer kinetochore modules bridge distances of well over 100 nm. DOI:http://dx.doi.org/10.7554/eLife.21007.001
Collapse
Affiliation(s)
- Pim J Huis In 't Veld
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Sadasivam Jeganathan
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Arsen Petrovic
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Priyanka Singh
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Juliane John
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Veronica Krenn
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Florian Weissmann
- Research Institute of Molecular Pathology (IMP), Vienna, Austria.,Vienna Biocenter (VBC), Vienna, Austria
| | - Tanja Bange
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Andrea Musacchio
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany.,Centre for Medical Biotechnology, University Duisburg-Essen, Essen, Germany.,Faculty of Biology, University Duisburg-Essen, Essen, Germany
| |
Collapse
|
20
|
Chung HJ, Park JE, Lee NS, Kim H, Jang CY. Phosphorylation of Astrin Regulates Its Kinetochore Function. J Biol Chem 2016; 291:17579-92. [PMID: 27325694 PMCID: PMC5016155 DOI: 10.1074/jbc.m115.712745] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 06/16/2016] [Indexed: 01/09/2023] Open
Abstract
The error-free segregation of chromosomes, which requires the precisely timed search and capture of chromosomes by spindles during early mitotic and meiotic cell division, is responsible for genomic stability and is achieved by the spindle assembly checkpoint in the metaphase-anaphase transition. Mitotic kinases orchestrate M phase events, such as the reorganization of cell architecture and kinetochore (KT) composition with the exquisite phosphorylation of mitotic regulators, to ensure timely and temporal progression. However, the molecular mechanisms underlying the changes of KT composition for stable spindle attachment during mitosis are poorly understood. Here, we show that the sequential action of the kinase Cdk1 and the phosphatase Cdc14A control spindle attachment to KTs. During prophase, the mitotic spindle protein Spag5/Astrin is transported into centrosomes by Kinastrin and phosphorylated at Ser-135 and Ser-249 by Cdk1, which, in prometaphase, is loaded onto the spindle and targeted to KTs. We also demonstrate that Cdc14A dephosphorylates Astrin, and therefore the overexpression of Cdc14A sequesters Astrin in the centrosome and results in aberrant chromosome alignment. Mechanistically, Plk1 acts as an upstream kinase for Astrin phosphorylation by Cdk1 and targeting phospho-Astrin to KTs, leading to the recruitment of outer KT components, such as Cenp-E, and the stable attachment of spindles to KTs. These comprehensive findings reveal a regulatory circuit for protein targeting to KTs that controls the KT composition change of stable spindle attachment and chromosome integrity.
Collapse
Affiliation(s)
- Hee Jin Chung
- Department of Biological Sciences, Sungkyunkwan University, Suwon 440-746, Republic of Korea and
| | - Ji Eun Park
- Research Center for Cell Fate Control, College of Pharmacy, Sookmyung Women's University, Seoul 04310, Republic of Korea
| | - Nam Soo Lee
- Department of Biological Sciences, Sungkyunkwan University, Suwon 440-746, Republic of Korea and
| | - Hongtae Kim
- Department of Biological Sciences, Sungkyunkwan University, Suwon 440-746, Republic of Korea and From the Center for Neuroscience Imaging Research, Institute for Basic Science and
| | - Chang-Young Jang
- Research Center for Cell Fate Control, College of Pharmacy, Sookmyung Women's University, Seoul 04310, Republic of Korea
| |
Collapse
|
21
|
Kinetochore assembly and function through the cell cycle. Chromosoma 2016; 125:645-59. [DOI: 10.1007/s00412-016-0608-3] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 06/21/2016] [Accepted: 06/22/2016] [Indexed: 01/03/2023]
|
22
|
Magidson V, He J, Ault JG, O'Connell CB, Yang N, Tikhonenko I, McEwen BF, Sui H, Khodjakov A. Unattached kinetochores rather than intrakinetochore tension arrest mitosis in taxol-treated cells. J Cell Biol 2016; 212:307-19. [PMID: 26833787 PMCID: PMC4748573 DOI: 10.1083/jcb.201412139] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Taxol induces extensive structural reorganization of the mammalian kinetochore; however, this reorganization is not sufficient to maintain a long-term mitotic arrest unless some of the kinetochores completely lose their attachment to microtubules. Kinetochores attach chromosomes to the spindle microtubules and signal the spindle assembly checkpoint to delay mitotic exit until all chromosomes are attached. Light microscopy approaches aimed to indirectly determine distances between various proteins within the kinetochore (termed Delta) suggest that kinetochores become stretched by spindle forces and compact elastically when the force is suppressed. Low Delta is believed to arrest mitotic progression in taxol-treated cells. However, the structural basis of Delta remains unknown. By integrating same-kinetochore light microscopy and electron microscopy, we demonstrate that the value of Delta is affected by the variability in the shape and size of outer kinetochore domains. The outer kinetochore compacts when spindle forces are maximal during metaphase. When the forces are weakened by taxol treatment, the outer kinetochore expands radially and some kinetochores completely lose microtubule attachment, a condition known to arrest mitotic progression. These observations offer an alternative interpretation of intrakinetochore tension and question whether Delta plays a direct role in the control of mitotic progression.
Collapse
Affiliation(s)
- Valentin Magidson
- Wadsworth Center, New York State Department of Health, Albany, NY 12201
| | - Jie He
- Wadsworth Center, New York State Department of Health, Albany, NY 12201
| | - Jeffrey G Ault
- Wadsworth Center, New York State Department of Health, Albany, NY 12201
| | | | - Nachen Yang
- Wadsworth Center, New York State Department of Health, Albany, NY 12201
| | - Irina Tikhonenko
- Wadsworth Center, New York State Department of Health, Albany, NY 12201
| | - Bruce F McEwen
- Wadsworth Center, New York State Department of Health, Albany, NY 12201 School of Public Health, State University of New York, Albany, NY 12201
| | - Haixin Sui
- Wadsworth Center, New York State Department of Health, Albany, NY 12201 School of Public Health, State University of New York, Albany, NY 12201
| | - Alexey Khodjakov
- Wadsworth Center, New York State Department of Health, Albany, NY 12201 Rensselaer Polytechnic Institute, Troy, NY 12180
| |
Collapse
|
23
|
Abstract
The kinetochore connects chromosomes to microtubules during mitosis and therefore plays an essential role in faithful chromosome segregation. It is built at the centromeric region of the chromosome and is comprised of many protein complexes. CENP-S, -T, -W, and -X are kinetochore components with histone-folds. These proteins play important roles in establishment of kinetochore chromatin. Similar to canonical histones, these kinetochore histone-fold proteins form heteromeric complexes (CENP-S/CENP-X complex and CENP-T/CENP-W complex) and bind DNA in sequence independent manner. In addition, they form a CENP-T-W-S-X heterotetrameric complex and bind DNA in a manner that is different from both CENP-S-X and CENP-T-W. To understand how kinetochores form and function it is necessary to characterize the components in detail. Here, we describe our approaches in purification and characterization of the kinetochore histone-fold complexes.
Collapse
|
24
|
Wynne DJ, Funabiki H. Heterogeneous architecture of vertebrate kinetochores revealed by three-dimensional superresolution fluorescence microscopy. Mol Biol Cell 2016; 27:3395-3404. [PMID: 27170176 PMCID: PMC5221576 DOI: 10.1091/mbc.e16-02-0130] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 05/04/2016] [Indexed: 11/11/2022] Open
Abstract
Superresolution fluorescence microscopy of vertebrate kinetochore proteins reveals that outer kinetochore components assume diverse distribution patterns, including a ring-like configuration encircling the CENP-A–marked centromeric chromatin on the metaphase spindle in Xenopus egg extracts. The kinetochore is often depicted as having a disk-like architecture in which the outer layer of proteins, which engage microtubules and control checkpoint signaling, are built on a static inner layer directly linked to CENP-A chromatin. Here, applying three-dimensional (3D) structural illumination microscopy (SIM) and stochastic optical reconstruction microscopy (STORM) to Xenopus egg extracts and tissue culture cells, we report various distribution patterns of inner and outer kinetochore proteins. In egg extracts, a configuration in which outer kinetochore proteins surround the periphery of CENP-A chromatin is common, forming an ∼200-nm ring-like organization that may engage a bundle of microtubule ends. Similar rings are observed in Xenopus tissue culture cells at a lower frequency but are enriched in conditions in which the spindle is disorganized. Although rings are rare in human cells, the distribution of both inner and outer kinetochore proteins elongates in the absence of microtubule attachment in a manner dependent on Aurora B. We propose a model in which the 3D organization of both the outer and inner kinetochore regions respond to the progression from lateral to end-on microtubule attachments by coalescing into a tight disk from less uniform distributions early in prometaphase.
Collapse
Affiliation(s)
- David J Wynne
- Laboratory of Chromosome and Cell Biology, Rockefeller University, New York, NY 10065.,Department of Biology, College of New Jersey, Ewing, NJ 08628
| | - Hironori Funabiki
- Laboratory of Chromosome and Cell Biology, Rockefeller University, New York, NY 10065
| |
Collapse
|
25
|
Doherty K, Meere M, Piiroinen PT. A mathematical model of Aurora B activity in prophase and metaphase. Math Biosci 2016; 277:153-65. [PMID: 27155569 DOI: 10.1016/j.mbs.2016.04.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 04/26/2016] [Accepted: 04/27/2016] [Indexed: 10/21/2022]
Abstract
Aurora B kinase is a protein that controls several processes in mitosis when it is found associated with INCENP, Survivin and Borealin in a complex known as the Chromosomal Passenger Complex. Aurora B in complex with INCENP is phosphorylated on three sites, resulting in the full activation of Aurora B. In prophase and metaphase, Aurora B is activated at centromeres, the region of chromatin linking sister chromatids, due to an autophosphorylation mechanism, and it has been hypothesised that Aurora B is activated throughout the cytoplasm due to its concentration at centromeres. In this article, we first develop a time-dependent model of Aurora B activation that does not incorporate spatial variation. This model is used to demonstrate the various qualitative behaviours that the activation of Aurora B is capable of displaying for different model parameters. Next, we develop a spatio-temporal model of Aurora B activation that includes diffusion of soluble Aurora B and binding of Aurora B to immobile centromeric binding sites. This model describes the activation of Aurora B throughout the cytoplasm due to its concentration-dependent activation at centromeres. The models demonstrate the effects that a soluble phosphatase concentration, multisite phosphorylation and diffusion have on the activation of Aurora B.
Collapse
Affiliation(s)
- Kevin Doherty
- School of Mathematics, Statistics and Applied Mathematics, National University of Ireland, Galway, University Road, Galway, Ireland; AgroParisTech, CRNH-IdF, UMR914, Nutrition Physiology and Ingestive Behavior, Paris F-75005, France; INRA, CRNH-IdF, UMR914 Nutrition Physiology and Ingestive Behavior, Paris F-75005, France.
| | - Martin Meere
- School of Mathematics, Statistics and Applied Mathematics, National University of Ireland, Galway, University Road, Galway, Ireland.
| | - Petri T Piiroinen
- School of Mathematics, Statistics and Applied Mathematics, National University of Ireland, Galway, University Road, Galway, Ireland.
| |
Collapse
|
26
|
Pesenti ME, Weir JR, Musacchio A. Progress in the structural and functional characterization of kinetochores. Curr Opin Struct Biol 2016; 37:152-63. [PMID: 27039078 DOI: 10.1016/j.sbi.2016.03.003] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 03/10/2016] [Accepted: 03/10/2016] [Indexed: 10/22/2022]
Abstract
Kinetochores are macromolecular complexes built on a specialized chromatin domain called the centromere. Kinetochores provide a site of attachment for spindle microtubules during mitosis. They also control a cell cycle checkpoint, the spindle assembly checkpoint, which coordinates mitotic exit with the completion of chromosome alignment on the mitotic spindle. Correct kinetochore operation is therefore indispensable for accurate chromosome segregation. With multiple copies of at least 30 structural core subunits and a myriad of regulatory subunits, kinetochores are among the largest known macromolecular machines. Biochemical reconstitution and structural analysis, together with functional studies, are bringing to light the organizational principles of these complex and fascinating structures. We summarize recent work and identify a few challenges for future work.
Collapse
Affiliation(s)
- Marion E Pesenti
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - John R Weir
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Andrea Musacchio
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany; Centre for Medical Biotechnology, Faculty of Biology, University Duisburg-Essen, Universitätsstraße, 45141 Essen, Germany.
| |
Collapse
|
27
|
Etemad B, Kops GJPL. Attachment issues: kinetochore transformations and spindle checkpoint silencing. Curr Opin Cell Biol 2016; 39:101-8. [PMID: 26947988 DOI: 10.1016/j.ceb.2016.02.016] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 02/08/2016] [Accepted: 02/15/2016] [Indexed: 12/21/2022]
Abstract
Cell division culminates in the segregation of duplicated chromosomes in opposite directions prior to cellular fission. This process is guarded by the spindle assembly checkpoint (SAC), which prevents the anaphase of cell division until stable connections between spindle microtubules and the kinetochores of all chromosomes are established. The anaphase inhibitor is generated at unattached kinetochores and inhibitor production is prevented when microtubules are captured. Understanding the molecular changes in the kinetochore that are evoked by microtubule attachments is crucial for understanding the mechanisms of SAC signaling and silencing. Here, we highlight the most recent findings on these events, pinpoint some remaining mysteries, and argue for incorporating holistic views of kinetochore dynamics in order to understand SAC silencing.
Collapse
Affiliation(s)
- Banafsheh Etemad
- Hubrecht Institute - KNAW (Royal Netherlands Academy of Arts and Sciences), Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Geert J P L Kops
- Hubrecht Institute - KNAW (Royal Netherlands Academy of Arts and Sciences), Uppsalalaan 8, 3584 CT Utrecht, The Netherlands; Cancer Genomics Netherlands, University Medical Center Utrecht, 3584 CG Utrecht, The Netherlands; Center for Molecular Medicine, University Medical Center Utrecht, 3584 CG Utrecht, The Netherlands.
| |
Collapse
|
28
|
Wynne DJ, Funabiki H. Kinetochore function is controlled by a phospho-dependent coexpansion of inner and outer components. J Cell Biol 2015; 210:899-916. [PMID: 26347137 PMCID: PMC4576862 DOI: 10.1083/jcb.201506020] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
It is widely accepted that the kinetochore is built on CENP-A-marked centromeric chromatin in a hierarchical order from inner to outer kinetochore. Recruitment of many kinetochore proteins depends on microtubule attachment status, but it remains unclear how their assembly/disassembly is orchestrated. Applying 3D structured illumination microscopy to Xenopus laevis egg extracts, here we reveal that in the absence of microtubule attachment, proteins responsible for lateral attachment and spindle checkpoint signaling expand to form micrometer-scale fibrous structures over CENP-A-free chromatin, whereas a core module responsible for end-on attachment (CENP-A, CENP-T, and Ndc80) does not. Both outer kinetochore proteins (Bub1, BubR1, Mad1, and CENP-E) and the inner kinetochore component CENP-C are integral components of the expandable module, whose assembly depends on multiple mitotic kinases (Aurora B, Mps1, and Plx1) and is suppressed by protein phosphatase 1. We propose that phospho-dependent coexpansion of CENP-C and outer kinetochore proteins promotes checkpoint signal amplification and lateral attachment, whereas their selective disassembly enables the transition to end-on attachment.
Collapse
|
29
|
Kinetochore-microtubule attachment is sufficient to satisfy the human spindle assembly checkpoint. Nat Commun 2015; 6:8987. [PMID: 26621779 PMCID: PMC4686852 DOI: 10.1038/ncomms9987] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 10/22/2015] [Indexed: 01/10/2023] Open
Abstract
The spindle assembly checkpoint (SAC) is a genome surveillance mechanism that protects against aneuploidization. Despite profound progress on understanding mechanisms of its activation, it remains unknown what aspect of chromosome-spindle interactions is monitored by the SAC: kinetochore-microtubule attachment or the force generated by dynamic microtubules that signals stable biorientation of chromosomes? To answer this, we uncoupled these two processes by expressing a non-phosphorylatable version of the main microtubule-binding protein at kinetochores (HEC1-9A), causing stabilization of incorrect kinetochore-microtubule attachments despite persistent activity of the error-correction machinery. The SAC is fully functional in HEC1-9A-expressing cells, yet cells in which chromosomes cannot biorient but are stably attached to microtubules satisfy the SAC and exit mitosis. SAC satisfaction requires neither intra-kinetochore stretching nor dynamic microtubules. Our findings support the hypothesis that in human cells the end-on interactions of microtubules with kinetochores are sufficient to satisfy the SAC without the need for microtubule-based pulling forces.
Collapse
|
30
|
Tauchman EC, Boehm FJ, DeLuca JG. Stable kinetochore-microtubule attachment is sufficient to silence the spindle assembly checkpoint in human cells. Nat Commun 2015; 6:10036. [PMID: 26620470 PMCID: PMC4686653 DOI: 10.1038/ncomms10036] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 10/27/2015] [Indexed: 11/08/2022] Open
Abstract
During mitosis, duplicated sister chromatids attach to microtubules emanating from opposing sides of the bipolar spindle through large protein complexes called kinetochores. In the absence of stable kinetochore-microtubule attachments, a cell surveillance mechanism known as the spindle assembly checkpoint (SAC) produces an inhibitory signal that prevents anaphase onset. Precisely how the inhibitory SAC signal is extinguished in response to microtubule attachment remains unresolved. To address this, we induced formation of hyper-stable kinetochore-microtubule attachments in human cells using a non-phosphorylatable version of the protein Hec1, a core component of the attachment machinery. We find that stable attachments are sufficient to silence the SAC in the absence of sister kinetochore bi-orientation and strikingly in the absence of detectable microtubule pulling forces or tension. Furthermore, we find that SAC satisfaction occurs despite the absence of large changes in intra-kinetochore distance, suggesting that substantial kinetochore stretching is not required for quenching the SAC signal.
Collapse
Affiliation(s)
- Eric C. Tauchman
- Cell and Molecular Biology Program, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Frederick J. Boehm
- Department of Statistics, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Jennifer G. DeLuca
- Cell and Molecular Biology Program, Colorado State University, Fort Collins, Colorado 80523, USA
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado 80523, USA
| |
Collapse
|
31
|
A quantitative description of Ndc80 complex linkage to human kinetochores. Nat Commun 2015; 6:8161. [PMID: 26345214 PMCID: PMC4569735 DOI: 10.1038/ncomms9161] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 07/25/2015] [Indexed: 11/08/2022] Open
Abstract
The Ndc80 complex, which mediates end-on attachment of spindle microtubules, is linked to centromeric chromatin in human cells by two inner kinetochore proteins, CENP-T and CENP-C. Here to quantify their relative contributions to Ndc80 recruitment, we combine measurements of kinetochore protein copy number with selective protein depletion assays. This approach reveals about 244 Ndc80 complexes per human kinetochore (∼14 per kinetochore microtubule), 215 CENP-C, 72 CENP-T and only 151 Ndc80s as part of the KMN protein network (1:1:1 Knl1, Mis12 and Ndc80 complexes). Each CENP-T molecule recruits ∼2 Ndc80 complexes; one as part of a KMN network. In contrast, ∼40% of CENP-C recruits only a KMN network. Replacing the CENP-C domain that binds KMN with the CENP-T domain that recruits both an Ndc80 complex and KMN network yielded functional kinetochores. These results provide a quantitative picture of the linkages between centromeric chromatin and the microtubule-binding Ndc80 complex at the human kinetochore.
Collapse
|
32
|
Bertalan Z, La Porta CAM, Maiato H, Zapperi S. Conformational mechanism for the stability of microtubule-kinetochore attachments. Biophys J 2015; 107:289-300. [PMID: 25028871 DOI: 10.1016/j.bpj.2014.06.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 05/26/2014] [Accepted: 06/09/2014] [Indexed: 01/09/2023] Open
Abstract
Regulating the stability of microtubule (MT)-kinetochore attachments is fundamental to avoiding mitotic errors and ensuring proper chromosome segregation during cell division. Although biochemical factors involved in this process have been identified, their mechanics still need to be better understood. Here we introduce and simulate a mechanical model of MT-kinetochore interactions in which the stability of the attachment is ruled by the geometrical conformations of curling MT-protofilaments entangled in kinetochore fibrils. The model allows us to reproduce, with good accuracy, in vitro experimental measurements of the detachment times of yeast kinetochores from MTs under external pulling forces. Numerical simulations suggest that geometrical features of MT-protofilaments may play an important role in the switch between stable and unstable attachments.
Collapse
Affiliation(s)
- Zsolt Bertalan
- Institute for Scientific Interchange Foundation, Torino, Italy
| | | | - Helder Maiato
- Chromosome Instability and Dynamics Laboratory, Instituto de Biologia Molecular e Celular, University of Porto, Porto, Portugal; Cell Division Unit, Department of Experimental Biology, Faculty of Medicine, University of Porto, Porto, Portugal
| | - Stefano Zapperi
- Institute for Scientific Interchange Foundation, Torino, Italy; National Research Council of Italy, Istituto per l'Energetica e le Interfasi, Milano, Italy.
| |
Collapse
|
33
|
Samejima K, Platani M, Wolny M, Ogawa H, Vargiu G, Knight PJ, Peckham M, Earnshaw WC. The Inner Centromere Protein (INCENP) Coil Is a Single α-Helix (SAH) Domain That Binds Directly to Microtubules and Is Important for Chromosome Passenger Complex (CPC) Localization and Function in Mitosis. J Biol Chem 2015; 290:21460-72. [PMID: 26175154 PMCID: PMC4571873 DOI: 10.1074/jbc.m115.645317] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Indexed: 11/06/2022] Open
Abstract
The chromosome passenger complex (CPC) is a master regulator of mitosis. Inner centromere protein (INCENP) acts as a scaffold regulating CPC localization and activity. During early mitosis, the N-terminal region of INCENP forms a three-helix bundle with Survivin and Borealin, directing the CPC to the inner centromere where it plays essential roles in chromosome alignment and the spindle assembly checkpoint. The C-terminal IN box region of INCENP is responsible for binding and activating Aurora B kinase. The central region of INCENP has been proposed to comprise a coiled coil domain acting as a spacer between the N- and C-terminal domains that is involved in microtubule binding and regulation of the spindle checkpoint. Here we show that the central region (213 residues) of chicken INCENP is not a coiled coil but a ∼ 32-nm-long single α-helix (SAH) domain. The N-terminal half of this domain directly binds to microtubules in vitro. By analogy with previous studies of myosin 10, our data suggest that the INCENP SAH might stretch up to ∼ 80 nm under physiological forces. Thus, the INCENP SAH could act as a flexible "dog leash," allowing Aurora B to phosphorylate dynamic substrates localized in the outer kinetochore while at the same time being stably anchored to the heterochromatin of the inner centromere. Furthermore, by achieving this flexibility via an SAH domain, the CPC avoids a need for dimerization (required for coiled coil formation), which would greatly complicate regulation of the proximity-induced trans-phosphorylation that is critical for Aurora B activation.
Collapse
Affiliation(s)
- Kumiko Samejima
- From The Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, Scotland, United Kingdom and
| | - Melpomeni Platani
- From The Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, Scotland, United Kingdom and
| | - Marcin Wolny
- The Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Hiromi Ogawa
- From The Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, Scotland, United Kingdom and
| | - Giulia Vargiu
- From The Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, Scotland, United Kingdom and
| | - Peter J Knight
- The Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Michelle Peckham
- The Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - William C Earnshaw
- From The Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, Scotland, United Kingdom and
| |
Collapse
|
34
|
The Mps1 kinase modulates the recruitment and activity of Cnn1(CENP-T) at Saccharomyces cerevisiae kinetochores. Genetics 2015; 200:79-90. [PMID: 25716979 DOI: 10.1534/genetics.115.175786] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 02/24/2015] [Indexed: 02/04/2023] Open
Abstract
Kinetochores are conserved protein complexes that bind the replicated chromosomes to the mitotic spindle and then direct their segregation. To better comprehend Saccharomyces cerevisiae kinetochore function, we dissected the phospho-regulated dynamic interaction between conserved kinetochore protein Cnn1(CENP-T), the centromere region, and the Ndc80 complex through the cell cycle. Cnn1 localizes to kinetochores at basal levels from G1 through metaphase but accumulates abruptly at anaphase onset. How Cnn1 is recruited and which activities regulate its dynamic localization are unclear. We show that Cnn1 harbors two kinetochore-localization activities: a C-terminal histone-fold domain (HFD) that associates with the centromere region and a N-terminal Spc24/Spc25 interaction sequence that mediates linkage to the microtubule-binding Ndc80 complex. We demonstrate that the established Ndc80 binding site in the N terminus of Cnn1, Cnn1(60-84), should be extended with flanking residues, Cnn1(25-91), to allow near maximal binding affinity to Ndc80. Cnn1 localization was proposed to depend on Mps1 kinase activity at Cnn1-S74, based on in vitro experiments demonstrating the Cnn1-Ndc80 complex interaction. We demonstrate that from G1 through metaphase, Cnn1 localizes via both its HFD and N-terminal Spc24/Spc25 interaction sequence, and deletion or mutation of either region results in anomalous Cnn1 kinetochore levels. At anaphase onset (when Mps1 activity decreases) Cnn1 becomes enriched mainly via the N-terminal Spc24/Spc25 interaction sequence. In sum, we provide the first in vivo evidence of Cnn1 preanaphase linkages with the kinetochore and enrichment of the linkages during anaphase.
Collapse
|
35
|
Doherty K, Meere M, Piiroinen PT. Some mathematical models of intermolecular autophosphorylation. J Theor Biol 2015; 370:27-38. [PMID: 25636493 DOI: 10.1016/j.jtbi.2015.01.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 01/08/2015] [Accepted: 01/15/2015] [Indexed: 11/26/2022]
Abstract
Intermolecular autophosphorylation refers to the process whereby a molecule of an enzyme phosphorylates another molecule of the same enzyme. The enzyme thereby catalyses its own phosphorylation. In the present paper, we develop two generic models of intermolecular autophosphorylation that also include dephosphorylation by a phosphatase of constant concentration. The first of these, a solely time-dependent model, is written as one ordinary differential equation that relies upon mass-action and Michaelis-Menten kinetics. Beginning with the enzyme in its dephosphorylated state, it predicts a lag before the enzyme becomes significantly phosphorylated, for suitable parameter values. It also predicts that there exists a threshold concentration for the phosphorylation of enzyme and that for suitable parameter values, a continuous or discontinuous switch in the phosphorylation of enzyme are possible. The model developed here has the advantage that it is relatively easy to analyse compared with most existing models for autophosphorylation and can qualitatively describe many different systems. We also extend our time-dependent model of autophosphorylation to include a spatial dependence, as well as localised binding reactions. This spatio-temporal model consists of a system of partial differential equations that describe a soluble autophosphorylating enzyme in a spherical geometry. We use the spatio-temporal model to describe the phosphorylation of an enzyme throughout the cell due to an increase in local concentration by binding. Using physically realistic values for model parameters, our results provide a proof-of-concept of the process of activation by local concentration and suggest that, in the presence of a phosphatase, this activation can be irreversible.
Collapse
Affiliation(s)
- Kevin Doherty
- School of Mathematics, Statistics and Applied Mathematics, National University of Ireland, Galway, University Road, Galway, Ireland; AgroParisTech, CRNH-IdF, UMR914, Nutrition Physiology and Ingestive Behavior, F-75005 Paris, France; INRA, CRNH-IdF, UMR914 Nutrition Physiology and Ingestive Behavior, F-75005 Paris, France.
| | - Martin Meere
- School of Mathematics, Statistics and Applied Mathematics, National University of Ireland, Galway, University Road, Galway, Ireland.
| | - Petri T Piiroinen
- School of Mathematics, Statistics and Applied Mathematics, National University of Ireland, Galway, University Road, Galway, Ireland.
| |
Collapse
|
36
|
Abstract
Kinetochores orchestrate chromosome segregation during mitosis and must cope with dynamic forces generated by attached microtubules. In this issue of Developmental Cell, Suzuki et al. (2014) demonstrate that the constitutive centromere-associated network (CCAN) displays a complex architecture that plays a crucial role in resisting these forces.
Collapse
|
37
|
The architecture of CCAN proteins creates a structural integrity to resist spindle forces and achieve proper Intrakinetochore stretch. Dev Cell 2014; 30:717-30. [PMID: 25268173 DOI: 10.1016/j.devcel.2014.08.003] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 05/26/2014] [Accepted: 08/04/2014] [Indexed: 12/12/2022]
Abstract
Constitutive centromere-associated network (CCAN) proteins, particularly CENP-C, CENP-T, and the CENP-H/-I complex, mechanically link CENP-A-containing centromeric chromatin within the inner kinetochore to outer kinetochore proteins, such as the Ndc80 complex, that bind kinetochore microtubules. Accuracy of chromosome segregation depends critically upon Aurora B phosphorylation of Ndc80/Hec1. To determine how CCAN protein architecture mechanically constrains intrakinetochore stretch between CENP-A and Ndc80/Hec1 for proper Ndc80/Hec1 phosphorylation, we used super-resolution fluorescence microscopy and selective protein depletion. We found that at bi-oriented chromosomes in late prometaphase cells, CENP-T is stretched ∼16 nm to the inner end of Ndc80/Hec1, much less than expected for full-length CENP-T. Depletion of various CCAN linker proteins induced hyper-intrakinetochore stretch (an additional 20-60 nm) with corresponding significant decreases in Aurora B phosphorylation of Ndc80/Hec1. Thus, proper intrakinetochore stretch is required for normal kinetochore function and depends critically on all the CCAN mechanical linkers to the Ndc80 complex.
Collapse
|
38
|
Abstract
Since discovery of the centromere-specific histone H3 variant CENP-A, centromeres have come to be defined as chromatin structures that establish the assembly site for the complex kinetochore machinery. In most organisms, centromere activity is defined epigenetically, rather than by specific DNA sequences. In this review, we describe selected classic work and recent progress in studies of centromeric chromatin with a focus on vertebrates. We consider possible roles for repetitive DNA sequences found at most centromeres, chromatin factors and modifications that assemble and activate CENP-A chromatin for kinetochore assembly, plus the use of artificial chromosomes and kinetochores to study centromere function.
Collapse
Affiliation(s)
- Tatsuo Fukagawa
- Department of Molecular Genetics, National Institute of Genetics and Graduate University for Advanced Studies (SOKENDAI), Mishima, Shizuoka 411-8540, Japan.
| | - William C Earnshaw
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Mayfield Road, Edinburgh, EH9 3JR, UK.
| |
Collapse
|
39
|
Ando T. High-speed AFM imaging. Curr Opin Struct Biol 2014; 28:63-8. [DOI: 10.1016/j.sbi.2014.07.011] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 07/22/2014] [Accepted: 07/22/2014] [Indexed: 11/26/2022]
|
40
|
Nannas NJ, Murray AW. Tethering sister centromeres to each other suggests the spindle checkpoint detects stretch within the kinetochore. PLoS Genet 2014; 10:e1004492. [PMID: 25101645 PMCID: PMC4125069 DOI: 10.1371/journal.pgen.1004492] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 05/22/2014] [Indexed: 11/18/2022] Open
Abstract
The spindle checkpoint ensures that newly born cells receive one copy of each chromosome by preventing chromosomes from segregating until they are all correctly attached to the spindle. The checkpoint monitors tension to distinguish between correctly aligned chromosomes and those with both sisters attached to the same spindle pole. Tension arises when sister kinetochores attach to and are pulled toward opposite poles, stretching the chromatin around centromeres and elongating kinetochores. We distinguished between two hypotheses for where the checkpoint monitors tension: between the kinetochores, by detecting alterations in the distance between them, or by responding to changes in the structure of the kinetochore itself. To distinguish these models, we inhibited chromatin stretch by tethering sister chromatids together by binding a tetrameric form of the Lac repressor to arrays of the Lac operator located on either side of a centromere. Inhibiting chromatin stretch did not activate the spindle checkpoint; these cells entered anaphase at the same time as control cells that express a dimeric version of the Lac repressor, which cannot cross link chromatids, and cells whose checkpoint has been inactivated. There is no dominant checkpoint inhibition when sister kinetochores are held together: cells expressing the tetrameric Lac repressor still arrest in response to microtubule-depolymerizing drugs. Tethering chromatids together does not disrupt kinetochore function; chromosomes are successfully segregated to opposite poles of the spindle. Our results indicate that the spindle checkpoint does not monitor inter-kinetochore separation, thus supporting the hypothesis that tension is measured within the kinetochore. The spindle checkpoint monitors tension on chromosomes to distinguish between chromosomes that are correctly and incorrectly attached to the spindle. Tension is generated across a correctly attached chromosome as microtubules from opposite poles attach to and pull kinetochores apart, but are resisted by the cohesin that holds sister chromatids together. This tension generates separation between kinetochores as pericentric chromatin stretches and it also elongates the kinetochores. To monitor tension, the checkpoint could measure the separation between kinetochores or the stretch within them. We inhibited the ability of pericentric chromatin to stretch by tethering sister centromeres to each other, and we asked whether the resulting reduction in inter-kinetochore separation artificially activated the spindle checkpoint. Inhibiting inter-kinetochore separation does not delay anaphase, and the timing of mitosis was the same in cells with or without the spindle checkpoint, showing that the checkpoint is not activated. Inhibiting chromatin stretch does not alter the function of kinetochores as chromosomes are still segregated correctly, nor does it hinder the checkpoint. Cells whose sister kinetochores are held together can still activate the checkpoint in response to microtubule depolymerization. Our results indicate the spindle checkpoint does not monitor inter-kinetochore separation and likely monitors tension within kinetochores.
Collapse
Affiliation(s)
- Natalie J. Nannas
- Molecular and Cellular Biology Department, Harvard University, Cambridge, Massachusetts, United States of America
- FAS Center for Systems Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Andrew W. Murray
- Molecular and Cellular Biology Department, Harvard University, Cambridge, Massachusetts, United States of America
- FAS Center for Systems Biology, Harvard University, Cambridge, Massachusetts, United States of America
- * E-mail:
| |
Collapse
|
41
|
Basilico F, Maffini S, Weir JR, Prumbaum D, Rojas AM, Zimniak T, De Antoni A, Jeganathan S, Voss B, van Gerwen S, Krenn V, Massimiliano L, Valencia A, Vetter IR, Herzog F, Raunser S, Pasqualato S, Musacchio A. The pseudo GTPase CENP-M drives human kinetochore assembly. eLife 2014; 3:e02978. [PMID: 25006165 PMCID: PMC4080450 DOI: 10.7554/elife.02978] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Kinetochores, multi-subunit complexes that assemble at the interface with centromeres, bind spindle microtubules to ensure faithful delivery of chromosomes during cell division. The configuration and function of the kinetochore-centromere interface is poorly understood. We report that a protein at this interface, CENP-M, is structurally and evolutionarily related to small GTPases but is incapable of GTP-binding and conformational switching. We show that CENP-M is crucially required for the assembly and stability of a tetramer also comprising CENP-I, CENP-H, and CENP-K, the HIKM complex, which we extensively characterize through a combination of structural, biochemical, and cell biological approaches. A point mutant affecting the CENP-M/CENP-I interaction hampers kinetochore assembly and chromosome alignment and prevents kinetochore recruitment of the CENP-T/W complex, questioning a role of CENP-T/W as founder of an independent axis of kinetochore assembly. Our studies identify a single pathway having CENP-C as founder, and CENP-H/I/K/M and CENP-T/W as CENP-C-dependent followers.DOI: http://dx.doi.org/10.7554/eLife.02978.001.
Collapse
Affiliation(s)
- Federica Basilico
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany Department of Experimental Oncology, European Institute of Oncology, Milan, Italy
| | - Stefano Maffini
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - John R Weir
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Daniel Prumbaum
- Department of Physical Biochemistry, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Ana M Rojas
- Computational Biology and Bioinformatics Group, Institute of Biomedicine of Seville, Campus Hospital Universitario Virgen del Rocio, Seville, Spain
| | - Tomasz Zimniak
- Department of Biochemistry and Gene Center, Ludwig-Maximilians-Universität, München, Munich, Germany
| | - Anna De Antoni
- Department of Experimental Oncology, European Institute of Oncology, Milan, Italy
| | - Sadasivam Jeganathan
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Beate Voss
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Suzan van Gerwen
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Veronica Krenn
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany Department of Experimental Oncology, European Institute of Oncology, Milan, Italy
| | - Lucia Massimiliano
- Department of Experimental Oncology, European Institute of Oncology, Milan, Italy
| | - Alfonso Valencia
- Structural Biology and Biocomputing Programme, Spanish National Cancer Centre-CNIO, Madrid, Spain
| | - Ingrid R Vetter
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Franz Herzog
- Department of Biochemistry and Gene Center, Ludwig-Maximilians-Universität, München, Munich, Germany
| | - Stefan Raunser
- Department of Physical Biochemistry, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | | | - Andrea Musacchio
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany Centre for Medical Biotechnology, Faculty of Biology, University of Duisburg-Essen, Essen, Germany
| |
Collapse
|
42
|
Malvezzi F, Westermann S. "Uno, nessuno e centomila": the different faces of the budding yeast kinetochore. Chromosoma 2014; 123:447-57. [PMID: 24964966 DOI: 10.1007/s00412-014-0472-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Revised: 06/10/2014] [Accepted: 06/10/2014] [Indexed: 12/28/2022]
Abstract
"One, no one and one hundred thousand" is a masterpiece of Italian literature, written by Luigi Pirandello. The central theme is that in each individual there are multiple personalities, since one's perception of one's self differs from the view of others. As a consequence, a unique identity does not exist, but rather one hundred thousand. This concept can be very well applied to the kinetochore, one of the largest macromolecular complexes conserved in eukaryotes. The kinetochore is essential during cell division and fulfills different sophisticated functions, including linking chromosomes to spindle microtubules and delaying anaphase onset in case of incorrect bi-orientation. In order to perform these tasks, the kinetochore shapes its structure by recruiting different subunits, such as the components of the spindle assembly checkpoint (SAC) or the monopolin complex during meiosis. It also modifies its internal organization by rearranging intramolecular connections and acquiring a distinct identity at different time points of cell division. In this review, we describe recent insights into the changes in composition and configuration of the kinetochore in mitosis and meiosis, focusing on the kinetochore of Saccharomyces cerevisiae.
Collapse
Affiliation(s)
- Francesca Malvezzi
- Research Institute of Molecular Pathology (IMP), Dr. Bohr Gasse 7, 1030, Vienna, Austria
| | | |
Collapse
|
43
|
Ando T, Uchihashi T, Scheuring S. Filming biomolecular processes by high-speed atomic force microscopy. Chem Rev 2014; 114:3120-88. [PMID: 24476364 PMCID: PMC4076042 DOI: 10.1021/cr4003837] [Citation(s) in RCA: 231] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Indexed: 12/21/2022]
Affiliation(s)
- Toshio Ando
- Department of Physics, and Bio-AFM Frontier
Research Center, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
- CREST,
Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi 332-0012, Japan
| | - Takayuki Uchihashi
- Department of Physics, and Bio-AFM Frontier
Research Center, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
- CREST,
Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi 332-0012, Japan
| | - Simon Scheuring
- U1006
INSERM/Aix-Marseille Université, Parc Scientifique et Technologique
de Luminy Bâtiment Inserm TPR2 bloc 5, 163 avenue de Luminy, 13288 Marseille Cedex 9, France
| |
Collapse
|
44
|
Venkei Z, Przewloka MR, Ladak Y, Albadri S, Sossick A, Juhasz G, Novák B, Glover DM. Spatiotemporal dynamics of Spc105 regulates the assembly of the Drosophila kinetochore. Open Biol 2013; 2:110032. [PMID: 22645658 PMCID: PMC3352094 DOI: 10.1098/rsob.110032] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Accepted: 01/17/2012] [Indexed: 12/26/2022] Open
Abstract
The formation of kinetochores shortly before each cell division is a prerequisite for proper chromosome segregation. The synchronous mitoses of Drosophila syncytial embryos have provided an ideal in vivo system to follow kinetochore assembly kinetics and so address the question of how kinetochore formation is regulated. We found that the nuclear exclusion of the Spc105/KNL1 protein during interphase prevents precocious assembly of the Mis12 complex. The nuclear import of Spc105 in early prophase and its immediate association with the Mis12 complex on centromeres are thus the first steps in kinetochore assembly. The cumulative kinetochore levels of Spc105 and Mis12 complex then determine the rate of Ndc80 complex recruitment commencing only after nuclear envelope breakdown. The carboxy-terminal part of Spc105 directs its nuclear import and is sufficient for the assembly of all core kinetochore components and CENP-C, when localized ectopically to centrosomes. Super-resolution microscopy shows that carboxy-terminus of Spc105 lies at the junction of the Mis12 and Ndc80 complexes on stretched kinetochores. Our study thus indicates that physical accessibility of kinetochore components plays a crucial role in the regulation of Drosophila kinetochore assembly and leads us to a model in which Spc105 is a licensing factor for its onset.
Collapse
Affiliation(s)
- Zsolt Venkei
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH , UK
| | | | | | | | | | | | | | | |
Collapse
|
45
|
Westermann S, Schleiffer A. Family matters: structural and functional conservation of centromere-associated proteins from yeast to humans. Trends Cell Biol 2013; 23:260-9. [DOI: 10.1016/j.tcb.2013.01.010] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 01/22/2013] [Accepted: 01/31/2013] [Indexed: 01/19/2023]
|
46
|
Rago F, Cheeseman IM. Review series: The functions and consequences of force at kinetochores. ACTA ACUST UNITED AC 2013; 200:557-65. [PMID: 23460675 PMCID: PMC3587826 DOI: 10.1083/jcb.201211113] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Chromosome segregation requires the generation of force at the kinetochore—the multiprotein structure that facilitates attachment of chromosomes to spindle microtubules. This force is required both to move chromosomes and to signal the formation of proper bioriented attachments. To understand the role of force in these processes, it is critical to define how force is generated at kinetochores, the contributions of this force to chromosome movement, and how the kinetochore is structured and organized to withstand and respond to force. Classical studies and recent work provide a framework to dissect the mechanisms, functions, and consequences of force at kinetochores.
Collapse
Affiliation(s)
- Florencia Rago
- Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology, Cambridge, MA 0214, USA
| | | |
Collapse
|
47
|
Funabiki H, Wynne DJ. Making an effective switch at the kinetochore by phosphorylation and dephosphorylation. Chromosoma 2013; 122:135-58. [PMID: 23512483 DOI: 10.1007/s00412-013-0401-5] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Revised: 02/20/2013] [Accepted: 02/22/2013] [Indexed: 01/23/2023]
Abstract
The kinetochore, the proteinaceous structure on the mitotic centromere, functions as a mechanical latch that hooks onto microtubules to support directional movement of chromosomes. The structure also brings in a number of signaling molecules, such as kinases and phosphatases, which regulate microtubule dynamics and cell cycle progression. Erroneous microtubule attachment is destabilized by Aurora B-mediated phosphorylation of multiple microtubule-binding protein complexes at the kinetochore, such as the KMN network proteins and the Ska/Dam1 complex, while Plk-dependent phosphorylation of BubR1 stabilizes kinetochore-microtubule attachment by recruiting PP2A-B56. Spindle assembly checkpoint (SAC) signaling, which is activated by unattached kinetochores and inhibits the metaphase-to-anaphase transition, depends on kinetochore recruitment of the kinase Bub1 through Mps1-mediated phosphorylation of the kinetochore protein KNL1 (also known as Blinkin in mammals, Spc105 in budding yeast, and Spc7 in fission yeast). Recruitment of protein phosphatase 1 to KNL1 is necessary to silence the SAC upon bioriented microtubule attachment. One of the key unsolved questions in the mitosis field is how a mechanical change at the kinetochore upon microtubule attachment is converted to these and other chemical signals that control microtubule attachment and the SAC. Rapid progress in the field is revealing the existence of an intricate signaling network created right on the kinetochore. Here we review the current understanding of phosphorylation-mediated regulation of kinetochore functions and discuss how this signaling network generates an accurate switch that turns on and off the signaling output in response to kinetochore-microtubule attachment.
Collapse
Affiliation(s)
- Hironori Funabiki
- Laboratory of Chromosome and Cell Biology, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA.
| | | |
Collapse
|
48
|
Tanaka K. Regulatory mechanisms of kinetochore-microtubule interaction in mitosis. Cell Mol Life Sci 2013; 70:559-79. [PMID: 22752158 PMCID: PMC11113415 DOI: 10.1007/s00018-012-1057-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 05/29/2012] [Accepted: 06/11/2012] [Indexed: 12/17/2022]
Abstract
Interaction of microtubules with kinetochores is fundamental to chromosome segregation. Kinetochores initially associate with lateral surfaces of microtubules and subsequently become attached to microtubule ends. During these interactions, kinetochores can move by sliding along microtubules or by moving together with depolymerizing microtubule ends. The interplay between kinetochores and microtubules leads to the establishment of bi-orientation, which is the attachment of sister kinetochores to microtubules from opposite spindle poles, and subsequent chromosome segregation. Molecular mechanisms underlying these processes have been intensively studied over the past 10 years. Emerging evidence suggests that the KNL1-Mis12-Ndc80 (KMN) network plays a central role in connecting kinetochores to microtubules, which is under fine regulation by a mitotic kinase, Aurora B. However, a growing number of additional molecules are being shown to be involved in the kinetochore-microtubule interaction. Here I overview the current range of regulatory mechanisms of the kinetochore-microtubule interaction, and discuss how these multiple molecules contribute cooperatively to allow faithful chromosome segregation.
Collapse
Affiliation(s)
- Kozo Tanaka
- Department of Molecular Oncology, Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Miyagi, Japan.
| |
Collapse
|
49
|
CENP-T provides a structural platform for outer kinetochore assembly. EMBO J 2013; 32:424-36. [PMID: 23334297 DOI: 10.1038/emboj.2012.348] [Citation(s) in RCA: 148] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Accepted: 12/14/2012] [Indexed: 11/09/2022] Open
Abstract
The kinetochore forms a dynamic interface with microtubules from the mitotic spindle during mitosis. The Ndc80 complex acts as the key microtubule-binding complex at kinetochores. However, it is unclear how the Ndc80 complex associates with the inner kinetochore proteins that assemble upon centromeric chromatin. Here, based on a high-resolution structural analysis, we demonstrate that the N-terminal region of vertebrate CENP-T interacts with the 'RWD' domain in the Spc24/25 portion of the Ndc80 complex. Phosphorylation of CENP-T strengthens a cryptic hydrophobic interaction between CENP-T and Spc25 resulting in a phospho-regulated interaction that occurs without direct recognition of the phosphorylated residue. The Ndc80 complex interacts with both CENP-T and the Mis12 complex, but we find that these interactions are mutually exclusive, supporting a model in which two distinct pathways target the Ndc80 complex to kinetochores. Our results provide a model for how the multiple protein complexes at kinetochores associate in a phospho-regulated manner.
Collapse
|
50
|
Ludueña RF. A Hypothesis on the Origin and Evolution of Tubulin. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 302:41-185. [DOI: 10.1016/b978-0-12-407699-0.00002-9] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|