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Ghone DA, Evans EL, Bandini M, Stephenson KG, Sherer NM, Suzuki A. HIV-1 Vif disrupts phosphatase feedback regulation at the kinetochore, leading to a pronounced pseudo-metaphase arrest. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.30.605839. [PMID: 39131328 PMCID: PMC11312601 DOI: 10.1101/2024.07.30.605839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/13/2024]
Abstract
The human immunodeficiency virus type 1 (HIV-1) Virion Infectivity Factor (Vif) targets and degrades cellular APOBEC3 proteins, key regulators of intrinsic and innate antiretroviral immune responses, thereby facilitating HIV-1 infection. While Vif's role in degrading APOBEC3G is well-studied, Vif is also known to cause cell cycle arrest but the detailed nature of Vif's effects on the cell cycle has yet to be delineated. In this study, we employed high-temporal single-cell live imaging and super-resolution microscopy to monitor individual cells during Vif-induced cell cycle arrest. Our findings reveal that Vif does not affect the G2/M boundary as previously thought. Instead, Vif triggers a unique and robust pseudo-metaphase arrest, which is markedly distinct from the mild prometaphase arrest induced by the HIV-1 accessory protein, Vpr, known for modulating the cell cycle. During Vif-mediated arrest, chromosomes align properly to form a metaphase plate but later disassemble, resulting in polar chromosomes. Notably, unlike Vpr, Vif significantly reduces the levels of both Phosphatase 1 (PP1) and 2 (PP2) at kinetochores, which are key regulators of chromosome-microtubule interactions. These results reveal a novel function of Vif in kinetochore regulation that governs the spatial organization of chromosomes during mitosis.
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Affiliation(s)
- Dhaval A Ghone
- McArdle Laboratory for Cancer Research, Department of Oncology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Biophysics Graduate Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
- These authors contributed equally
| | - Edward L Evans
- McArdle Laboratory for Cancer Research, Department of Oncology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Cancer Biology Graduate Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
- These authors contributed equally
- Present address: Laboratory for Optical and Computational Instrumentation, University of Wisconsin-Madison, Madison, Wisconsin, 53705, USA
| | - Madison Bandini
- McArdle Laboratory for Cancer Research, Department of Oncology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Cancer Biology Graduate Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Kaelyn G Stephenson
- McArdle Laboratory for Cancer Research, Department of Oncology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Nathan M Sherer
- McArdle Laboratory for Cancer Research, Department of Oncology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Carbone Comprehensive Cancer Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Aussie Suzuki
- McArdle Laboratory for Cancer Research, Department of Oncology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Carbone Comprehensive Cancer Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
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2
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Corno A, Cordeiro MH, Allan LA, Lim Q, Harrington E, Smith RJ, Saurin AT. A bifunctional kinase-phosphatase module balances mitotic checkpoint strength and kinetochore-microtubule attachment stability. EMBO J 2023; 42:e112630. [PMID: 37712330 PMCID: PMC10577578 DOI: 10.15252/embj.2022112630] [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: 09/16/2022] [Revised: 08/23/2023] [Accepted: 08/28/2023] [Indexed: 09/16/2023] Open
Abstract
Two major mechanisms safeguard genome stability during mitosis: the mitotic checkpoint delays mitosis until all chromosomes have attached to microtubules, and the kinetochore-microtubule error-correction pathway keeps this attachment process free from errors. We demonstrate here that the optimal strength and dynamics of these processes are set by a kinase-phosphatase pair (PLK1-PP2A) that engage in negative feedback from adjacent phospho-binding motifs on the BUB complex. Uncoupling this feedback to skew the balance towards PLK1 produces a strong checkpoint, hypostable microtubule attachments and mitotic delays. Conversely, skewing the balance towards PP2A causes a weak checkpoint, hyperstable microtubule attachments and chromosome segregation errors. These phenotypes are associated with altered BUB complex recruitment to KNL1-MELT motifs, implicating PLK1-PP2A in controlling auto-amplification of MELT phosphorylation. In support, KNL1-BUB disassembly becomes contingent on PLK1 inhibition when KNL1 is engineered to contain excess MELT motifs. This elevates BUB-PLK1/PP2A complex levels on metaphase kinetochores, stabilises kinetochore-microtubule attachments, induces chromosome segregation defects and prevents KNL1-BUB disassembly at anaphase. Together, these data demonstrate how a bifunctional PLK1/PP2A module has evolved together with the MELT motifs to optimise BUB complex dynamics and ensure accurate chromosome segregation.
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Affiliation(s)
- Andrea Corno
- Cellular and Systems Medicine, School of MedicineUniversity of DundeeDundeeUK
| | - Marilia H Cordeiro
- Cellular and Systems Medicine, School of MedicineUniversity of DundeeDundeeUK
| | - Lindsey A Allan
- Cellular and Systems Medicine, School of MedicineUniversity of DundeeDundeeUK
| | - Qian‐Wei Lim
- Cellular and Systems Medicine, School of MedicineUniversity of DundeeDundeeUK
| | - Elena Harrington
- Cellular and Systems Medicine, School of MedicineUniversity of DundeeDundeeUK
| | - Richard J Smith
- Cellular and Systems Medicine, School of MedicineUniversity of DundeeDundeeUK
| | - Adrian T Saurin
- Cellular and Systems Medicine, School of MedicineUniversity of DundeeDundeeUK
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3
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Camlin NJ, Venkatachalam I, Evans JP. Oscillations in PP1 activity are essential for accurate progression through mammalian oocyte meiosis. Cell Cycle 2023; 22:1614-1636. [PMID: 37340734 PMCID: PMC10361142 DOI: 10.1080/15384101.2023.2225924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 04/17/2023] [Accepted: 06/12/2023] [Indexed: 06/22/2023] Open
Abstract
Tightly controlled fluctuations in kinase and phosphatase activity play important roles in regulating M-phase transitions. Protein Phosphatase 1 (PP1) is one of these phosphatases, with oscillations in PP1 activity driving mitotic M-phase. Evidence from a variety of experimental systems also points to roles in meiosis. Here, we report that PP1 is important for M-phase transitions through mouse oocyte meiosis. We employed a unique small-molecule approach to inhibit or activate PP1 at distinct phases of mouse oocyte meiosis. These studies show that temporal control of PP1 activity is essential for the G2/M transition, metaphase I/anaphase I transition, and the formation of a normal metaphase II oocyte. Our data also reveal that inappropriate activation of PP1 is more deleterious at the G2/M transition than at prometaphase I-to-metaphase I, and that an active pool of PP1 during prometaphase is vital for metaphase I/anaphase I transition and metaphase II chromosome alignment. Taken together, these results establish that loss of oscillations in PP1 activity causes a range of severe meiotic defects, pointing to essential roles for PP1 in female fertility, and more broadly, M-phase regulation.
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Affiliation(s)
- Nicole J. Camlin
- Department of Biological Sciences, Purdue University, West Lafayette, INUnited States
| | - Ilakkiya Venkatachalam
- Department of Biological Sciences, Purdue University, West Lafayette, INUnited States
- Department of Human Genetics, University of Michigan, Ann Arbor, MIUnited States
| | - Janice P. Evans
- Department of Biological Sciences, Purdue University, West Lafayette, INUnited States
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4
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Fu Y, Jia X, Yuan J, Yang Y, Zhang T, Yu Q, Zhou J, Wang T. Fam72a functions as a cell-cycle-controlled gene during proliferation and antagonizes apoptosis through reprogramming PP2A substrates. Dev Cell 2023; 58:398-415.e7. [PMID: 36868233 DOI: 10.1016/j.devcel.2023.02.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 06/28/2022] [Accepted: 02/09/2023] [Indexed: 03/05/2023]
Abstract
The cell cycle is key to life. After decades of research, it is unclear whether any parts of this process have yet to be identified. Fam72a is a poorly characterized gene and is evolutionarily conserved across multicellular organisms. Here, we have found that Fam72a is a cell-cycle-regulated gene that is transcriptionally and post-transcriptionally regulated by FoxM1 and APC/C, respectively. Functionally, Fam72a directly binds to tubulin and both the Aα and B56 subunits of PP2A-B56 to modulate tubulin and Mcl1 phosphorylation, which in turn affects the progression of the cell cycle and signaling of apoptosis. Moreover, Fam72a is involved in early responses to chemotherapy, and it efficiently antagonizes various anticancer compounds such as CDK and Bcl2 inhibitors. Thus, Fam72a switches the tumor-suppressive PP2A to be oncogenic by reprogramming its substrates. These findings identify a regulatory axis of PP2A and a protein member in the cell cycle and tumorigenesis regulatory network in human cells.
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Affiliation(s)
- Yuan Fu
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China; Department of Thoracic Oncology, Tianjin Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Tianjin Lung Cancer Center, Tianjin Medical University, Tianjin 300070, China.
| | - Xiaofan Jia
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China
| | - Jinwei Yuan
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China
| | - Yuting Yang
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China
| | - Teng Zhang
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China
| | - Qiujing Yu
- Department of Immunology and Key Laboratory of Immune Microenvironment and Disease, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China
| | - Jun Zhou
- Department of Genetics and Cell Biology, State Key Laboratory of Medicinal Chemical Biology, Haihe Laboratory of Cell Ecosystem, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Ting Wang
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China; Department of Thoracic Oncology, Tianjin Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Tianjin Lung Cancer Center, Tianjin Medical University, Tianjin 300070, China.
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5
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Lee HS, Min S, Jung YE, Chae S, Heo J, Lee JH, Kim T, Kang HC, Nakanish M, Cha SS, Cho H. Spatiotemporal coordination of the RSF1-PLK1-Aurora B cascade establishes mitotic signaling platforms. Nat Commun 2021; 12:5931. [PMID: 34635673 PMCID: PMC8505570 DOI: 10.1038/s41467-021-26220-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 09/15/2021] [Indexed: 12/03/2022] Open
Abstract
The chromatin remodeler RSF1 enriched at mitotic centromeres is essential for proper chromosome alignment and segregation and underlying mechanisms remain to be disclosed. We here show that PLK1 recruitment by RSF1 at centromeres creates an activating phosphorylation on Thr236 in the activation loop of Aurora B and this is indispensable for the Aurora B activation. In structural modeling the phosphorylated Thr236 enhances the base catalysis by Asp200 nearby, facilitating the Thr232 autophosphorylation. Accordingly, RSF1-PLK1 is central for Aurora B-mediated microtubule destabilization in error correction. However, under full microtubule-kinetochore attachment RSF1-PLK1 positions at kinetochores, halts activating Aurora B and phosphorylates BubR1, regardless of tension. Spatial movement of RSF1-PLK1 to kinetochores is triggered by Aurora B-mediated phosphorylation of centromeric histone H3 on Ser28. We propose a regulatory RSF1-PLK1 axis that spatiotemporally controls on/off switch on Aurora B. This feedback circuit among RSF1-PLK1-Aurora B may coordinate dynamic microtubule-kinetochore attachment in early mitosis when full tension yet to be generated.
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Affiliation(s)
- Ho-Soo Lee
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, Suwon, 16499, Korea.
| | - Sunwoo Min
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, Suwon, 16499, Korea
| | - Ye-Eun Jung
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Sunyoung Chae
- Institute of Medical Science, Ajou University School of Medicine, Suwon, 16499, Korea
| | - June Heo
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, Suwon, 16499, Korea
- Department of Biomedical Sciences, Graduate School of Ajou University, Suwon, 16499, Korea
| | - Jae-Ho Lee
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, Suwon, 16499, Korea
- Institute of Medical Science, Ajou University School of Medicine, Suwon, 16499, Korea
| | - TaeSoo Kim
- Department of Life Science, Ewha Womans University, Seoul, 03760, Korea
| | - Ho-Chul Kang
- Department of Physiology, Ajou University School of Medicine, Suwon, Korea
| | - Makoto Nakanish
- Division of Cancer Cell Biology, The University of Tokyo, Tokyo, 108-8639, Japan
| | - Sun-Shin Cha
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Hyeseong Cho
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, Suwon, 16499, Korea.
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6
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Wartosch L, Schindler K, Schuh M, Gruhn JR, Hoffmann ER, McCoy RC, Xing J. Origins and mechanisms leading to aneuploidy in human eggs. Prenat Diagn 2021; 41:620-630. [PMID: 33860956 PMCID: PMC8237340 DOI: 10.1002/pd.5927] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 01/02/2021] [Accepted: 02/21/2021] [Indexed: 11/18/2022]
Abstract
The gain or loss of a chromosome-or aneuploidy-acts as one of the major triggers for infertility and pregnancy loss in humans. These chromosomal abnormalities affect more than 40% of eggs in women at both ends of the age spectrum, that is, young girls as well as women of advancing maternal age. Recent studies in human oocytes and embryos using genomics, cytogenetics, and in silico modeling all provide new insight into the rates and potential genetic and cellular factors associated with aneuploidy at varying stages of development. Here, we review recent studies that are shedding light on potential molecular mechanisms of chromosome missegregation in oocytes and embryos across the entire female reproductive life span.
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Affiliation(s)
- Lena Wartosch
- Department of MeiosisMax Planck Institute for Biophysical ChemistryGöttingenGermany
| | - Karen Schindler
- Department of GeneticsRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Human Genetics Institute of New JerseyRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - Melina Schuh
- Department of MeiosisMax Planck Institute for Biophysical ChemistryGöttingenGermany
| | - Jennifer R. Gruhn
- DNRF Center for Chromosome StabilityDepartment of Cellular and Molecular MedicineFaculty of Health and Medical SciencesUniversity of CopenhagenDenmark
| | - Eva R. Hoffmann
- DNRF Center for Chromosome StabilityDepartment of Cellular and Molecular MedicineFaculty of Health and Medical SciencesUniversity of CopenhagenDenmark
| | - Rajiv C. McCoy
- Department of BiologyJohns Hopkins UniversityBaltimoreMarylandUSA
| | - Jinchuan Xing
- Department of GeneticsRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Human Genetics Institute of New JerseyRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
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7
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Cell-cycle phospho-regulation of the kinetochore. Curr Genet 2021; 67:177-193. [PMID: 33221975 DOI: 10.1007/s00294-020-01127-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 10/27/2020] [Accepted: 10/29/2020] [Indexed: 02/07/2023]
Abstract
The kinetochore is a mega-dalton protein assembly that forms within centromeric regions of chromosomes and directs their segregation during cell division. Here we review cell cycle-mediated phosphorylation events at the kinetochore, with a focus on the budding yeast Saccharomyces cerevisiae and the insight gained from forced associations of kinases and phosphatases. The point centromeres found in the budding yeast S. cerevisiae are one of the simplest such structures found in eukaryotes. The S. cerevisiae kinetochore comprises a single nucleosome, containing a centromere-specific H3 variant Cse4CENP-A, bound to a set of kinetochore proteins that connect to a single microtubule. Despite the simplicity of the budding yeast kinetochore, the proteins are mostly homologous with their mammalian counterparts. In some cases, human proteins can complement their yeast orthologs. Like its mammalian equivalent, the regulation of the budding yeast kinetochore is complex: integrating signals from the cell cycle, checkpoints, error correction, and stress pathways. The regulatory signals from these diverse pathways are integrated at the kinetochore by post-translational modifications, notably phosphorylation and dephosphorylation, to control chromosome segregation. Here we highlight the complex interplay between the activity of the different cell-cycle kinases and phosphatases at the kinetochore, emphasizing how much more we have to understand this essential structure.
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8
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A stochastic model for error correction of kinetochore-microtubule attachments in budding yeast. PLoS One 2020; 15:e0236293. [PMID: 32760074 PMCID: PMC7410253 DOI: 10.1371/journal.pone.0236293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 07/01/2020] [Indexed: 12/05/2022] Open
Abstract
To divide replicated chromosomes equally between daughter cells, kinetochores must attach to microtubules emanating from opposite poles of the mitotic spindle (biorientation). An error correction mechanism facilitates this process by destabilizing erroneous kinetochore-microtubule attachments. Here we present a stochastic model of kinetochore-microtubule attachments, via an essential protein Ndc80 in budding yeast, Saccharomyces cerevisiae. Using the model, we calculate the stochastic dynamics of a pair of sister kinetochores as they transition among different attachment states. First of all, we determine the kinase-to-phosphatase balance point that maximizes the probability of biorientation, while starting from an erroneous attachment state. We find that the balance point is sensitive to the rates of microtubule-Ndc80 dissociation and derive an approximate analytical formula that defines the balance point. Secondly, we determine the probability of transition from low-tension amphitelic to monotelic attachment and find that, despite this probability being approximately 33%, biorientation can be achieved with high probability. Thirdly, we calculate the contribution of the geometrical orientation of sister kinetochores to the probability of biorientation and show that, in the absence of geometrical orientation, the biorientation error rate is much larger than that observed in experiments. Finally, we study the coupling of the error correction mechanism to the spindle assembly checkpoint by calculating the average binding of checkpoint-related proteins to the kinetochore during the error correction process.
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9
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Conti D, Gul P, Islam A, Martín-Durán JM, Pickersgill RW, Draviam VM. Kinetochores attached to microtubule-ends are stabilised by Astrin bound PP1 to ensure proper chromosome segregation. eLife 2019; 8:49325. [PMID: 31808746 PMCID: PMC6930079 DOI: 10.7554/elife.49325] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 12/01/2019] [Indexed: 12/12/2022] Open
Abstract
Microtubules segregate chromosomes by attaching to macromolecular kinetochores. Only microtubule-end attached kinetochores can be pulled apart; how these end-on attachments are selectively recognised and stabilised is not known. Using the kinetochore and microtubule-associated protein, Astrin, as a molecular probe, we show that end-on attachments are rapidly stabilised by spatially-restricted delivery of PP1 near the C-terminus of Ndc80, a core kinetochore-microtubule linker. PP1 is delivered by the evolutionarily conserved tail of Astrin and this promotes Astrin’s own enrichment creating a highly-responsive positive feedback, independent of biorientation. Abrogating Astrin:PP1-delivery disrupts attachment stability, which is not rescued by inhibiting Aurora-B, an attachment destabiliser, but is reversed by artificially tethering PP1 near the C-terminus of Ndc80. Constitutive Astrin:PP1-delivery disrupts chromosome congression and segregation, revealing a dynamic mechanism for stabilising attachments. Thus, Astrin-PP1 mediates a dynamic ‘lock’ that selectively and rapidly stabilises end-on attachments, independent of biorientation, and ensures proper chromosome segregation.
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Affiliation(s)
- Duccio Conti
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom.,Department of Genetics, University of Cambridge, Cambridge, United Kingdom
| | - Parveen Gul
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - Asifa Islam
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - José M Martín-Durán
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - Richard W Pickersgill
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - Viji M Draviam
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom.,Department of Genetics, University of Cambridge, Cambridge, United Kingdom
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10
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Moura M, Conde C. Phosphatases in Mitosis: Roles and Regulation. Biomolecules 2019; 9:E55. [PMID: 30736436 PMCID: PMC6406801 DOI: 10.3390/biom9020055] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 01/31/2019] [Accepted: 02/01/2019] [Indexed: 02/07/2023] Open
Abstract
Mitosis requires extensive rearrangement of cellular architecture and of subcellular structures so that replicated chromosomes can bind correctly to spindle microtubules and segregate towards opposite poles. This process originates two new daughter nuclei with equal genetic content and relies on highly-dynamic and tightly regulated phosphorylation of numerous cell cycle proteins. A burst in protein phosphorylation orchestrated by several conserved kinases occurs as cells go into and progress through mitosis. The opposing dephosphorylation events are catalyzed by a small set of protein phosphatases, whose importance for the accuracy of mitosis is becoming increasingly appreciated. This review will focus on the established and emerging roles of mitotic phosphatases, describe their structural and biochemical properties, and discuss recent advances in understanding the regulation of phosphatase activity and function.
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Affiliation(s)
- Margarida Moura
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal.
- i3S-Instituto de Investigação e Inovação em Saúde da Universidade do Porto, 4200-135, Porto, Portugal.
- Programa Doutoral em Biologia Molecular e Celular (MCbiology), Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, 4050-313 Porto, Portugal.
| | - Carlos Conde
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal.
- i3S-Instituto de Investigação e Inovação em Saúde da Universidade do Porto, 4200-135, Porto, Portugal.
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11
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Gil RS, Vagnarelli P. Protein phosphatases in chromatin structure and function. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1866:90-101. [PMID: 30036566 PMCID: PMC6227384 DOI: 10.1016/j.bbamcr.2018.07.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 06/29/2018] [Accepted: 07/18/2018] [Indexed: 12/19/2022]
Abstract
Chromatin structure and dynamics are highly controlled and regulated processes that play an essential role in many aspects of cell biology. The chromatin transition stages and the factors that control this process are regulated by post-translation modifications, including phosphorylation. While the role of protein kinases in chromatin dynamics has been quite well studied, the nature and regulation of the counteracting phosphatases represent an emerging field but are still at their infancy. In this review we summarize the current literature on phosphatases involved in the regulation of chromatin structure and dynamics, with emphases on the major knowledge gaps that should require attention and more investigation.
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Affiliation(s)
- Raquel Sales Gil
- Colleges of Health and Life Science, Research Institute for Environment Health and Society, Brunel University London, London UB8 3PH, UK
| | - Paola Vagnarelli
- Colleges of Health and Life Science, Research Institute for Environment Health and Society, Brunel University London, London UB8 3PH, UK.
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12
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Saurin AT. Kinase and Phosphatase Cross-Talk at the Kinetochore. Front Cell Dev Biol 2018; 6:62. [PMID: 29971233 PMCID: PMC6018199 DOI: 10.3389/fcell.2018.00062] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 05/31/2018] [Indexed: 01/26/2023] Open
Abstract
Multiple kinases and phosphatases act on the kinetochore to control chromosome segregation: Aurora B, Mps1, Bub1, Plk1, Cdk1, PP1, and PP2A-B56, have all been shown to regulate both kinetochore-microtubule attachments and the spindle assembly checkpoint. Given that so many kinases and phosphatases converge onto two key mitotic processes, it is perhaps not surprising to learn that they are, quite literally, entangled in cross-talk. Inhibition of any one of these enzymes produces secondary effects on all the others, which results in a complicated picture that is very difficult to interpret. This review aims to clarify this picture by first collating the direct effects of each enzyme into one overarching schematic of regulation at the Knl1/Mis12/Ndc80 (KMN) network (a major signaling hub at the outer kinetochore). This schematic will then be used to discuss the implications of the cross-talk that connects these enzymes; both in terms of why it may be needed to produce the right type of kinetochore signals and why it nevertheless complicates our interpretations about which enzymes control what processes. Finally, some general experimental approaches will be discussed that could help to characterize kinetochore signaling by dissociating the direct from indirect effect of kinase or phosphatase inhibition in vivo. Together, this review should provide a framework to help understand how a network of kinases and phosphatases cooperate to regulate two key mitotic processes.
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Affiliation(s)
- Adrian T. Saurin
- Jacqui Wood Cancer Centre, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, United Kingdom
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