1
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Medley JC, Yim RN, DiPanni J, Sebou B, Shaffou B, Cramer E, Wu C, Kabara M, Song MH. Site-specific phosphorylation of ZYG-1 regulates ZYG-1 stability and centrosome number. iScience 2023; 26:108410. [PMID: 38034351 PMCID: PMC10687292 DOI: 10.1016/j.isci.2023.108410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 08/21/2023] [Accepted: 11/03/2023] [Indexed: 12/02/2023] Open
Abstract
Spindle bipolarity is critical for genomic integrity. As centrosome number often dictates bipolarity, tight control of centrosome assembly is vital for faithful cell division. The master centrosome regulator ZYG-1/Plk4 plays a pivotal role in this process. In C. elegans, casein kinase II (CK2) negatively regulates centrosome duplication by controlling centrosome-associated ZYG-1 levels. Here, we investigated CK2 as a regulator of ZYG-1 and its impact on centrosome assembly. We show that CK2 phosphorylates ZYG-1 in vitro and physically interacts with ZYG-1 in vivo. Depleting CK2 or blocking ZYG-1 phosphorylation at CK2 target sites leads to centrosome amplification. Non-phosphorylatable ZYG-1 mutants exhibit elevated ZYG-1 levels, leading to increased ZYG-1 and downstream factors at centrosomes, thus driving centrosome amplification. Moreover, inhibiting the 26S proteasome prevents degradation of the phospho-mimetic ZYG-1. Our findings suggest that CK2-dependent phosphorylation of ZYG-1 controls ZYG-1 levels via proteasomal degradation to limit centrosome number.
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Affiliation(s)
- Jeffrey C. Medley
- Department of Biological Sciences, Oakland University, Rochester, MI, USA
| | - Rachel N. Yim
- Department of Biological Sciences, Oakland University, Rochester, MI, USA
| | - Joseph DiPanni
- Department of Biological Sciences, Oakland University, Rochester, MI, USA
| | - Brandon Sebou
- Department of Biological Sciences, Oakland University, Rochester, MI, USA
| | - Blake Shaffou
- Department of Biological Sciences, Oakland University, Rochester, MI, USA
| | - Evan Cramer
- Department of Chemistry, Oakland University, Rochester, MI, USA
| | - Colin Wu
- Department of Chemistry, Oakland University, Rochester, MI, USA
| | - Megan Kabara
- Department of Biological Sciences, Oakland University, Rochester, MI, USA
- University of Connecticut School of Medicine, Office of Graduate Medical Education, Farmington, CT, USA
| | - Mi Hye Song
- Department of Biological Sciences, Oakland University, Rochester, MI, USA
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2
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Whyte D, Skalka G, Walsh P, Wilczynska A, Paul NR, Mitchell C, Nixon C, Clarke W, Bushell M, Morton JP, Murphy DJ, Muthalagu N. NUAK1 governs centrosome replication in pancreatic cancer via MYPT1/PP1β and GSK3β-dependent regulation of PLK4. Mol Oncol 2023; 17:1212-1227. [PMID: 36975767 PMCID: PMC10323901 DOI: 10.1002/1878-0261.13425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 03/08/2023] [Accepted: 03/24/2023] [Indexed: 03/29/2023] Open
Abstract
The AMP-activated protein kinase (AMPK)-related kinase NUAK1 (NUAK family SNF1-like kinase 1) has emerged as a potential vulnerability in MYC-dependent cancer but the biological roles of NUAK1 in different settings are poorly characterised, and the spectrum of cancer types that exhibit a requirement for NUAK1 is unknown. Unlike canonical oncogenes, NUAK1 is rarely mutated in cancer and appears to function as an obligate facilitator rather than a cancer driver per se. Although numerous groups have developed small-molecule NUAK inhibitors, the circumstances that would trigger their use and the unwanted toxicities that may arise as a consequence of on-target activity are thus undetermined. Reasoning that MYC is a key effector of RAS pathway signalling and the GTPase KRAS is almost uniformly mutated in pancreatic ductal adenocarcinoma (PDAC), we investigated whether this cancer type exhibits a functional requirement for NUAK1. Here, we show that high NUAK1 expression is associated with reduced overall survival in PDAC and that inhibition or depletion of NUAK1 suppresses growth of PDAC cells in culture. We identify a previously unknown role for NUAK1 in regulating accurate centrosome duplication and show that loss of NUAK1 triggers genomic instability. The latter activity is conserved in primary fibroblasts, raising the possibility of undesirable genotoxic effects of NUAK1 inhibition.
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Affiliation(s)
- Declan Whyte
- School of Cancer SciencesUniversity of GlasgowUK
- CRUK Beatson InstituteGlasgowUK
| | - George Skalka
- School of Cancer SciencesUniversity of GlasgowUK
- CRUK Beatson InstituteGlasgowUK
| | - Peter Walsh
- School of Cancer SciencesUniversity of GlasgowUK
- CRUK Beatson InstituteGlasgowUK
| | | | | | | | | | | | - Martin Bushell
- School of Cancer SciencesUniversity of GlasgowUK
- CRUK Beatson InstituteGlasgowUK
| | - Jennifer P. Morton
- School of Cancer SciencesUniversity of GlasgowUK
- CRUK Beatson InstituteGlasgowUK
| | - Daniel J. Murphy
- School of Cancer SciencesUniversity of GlasgowUK
- CRUK Beatson InstituteGlasgowUK
| | - Nathiya Muthalagu
- School of Cancer SciencesUniversity of GlasgowUK
- CRUK Beatson InstituteGlasgowUK
- Present address:
Indian Institute of TechnologyMadrasIndia
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3
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Medley JC, Yim N, DiPanni J, Sebou B, Shaffou B, Cramer E, Wu C, Kabara M, Song MH. Site-Specific Phosphorylation of ZYG-1 Regulates ZYG-1 Stability and Centrosome Number. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.07.539463. [PMID: 37333374 PMCID: PMC10274923 DOI: 10.1101/2023.05.07.539463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Spindle bipolarity is critical for genomic integrity. Given that centrosome number often dictates mitotic bipolarity, tight control of centrosome assembly is vital for the fidelity of cell division. The kinase ZYG-1/Plk4 is a master centrosome factor that is integral for controlling centrosome number and is modulated by protein phosphorylation. While autophosphorylation of Plk4 has been extensively studied in other systems, the mechanism of ZYG-1 phosphorylation in C. elegans remains largely unexplored. In C. elegans, Casein Kinase II (CK2) negatively regulates centrosome duplication by controlling centrosome-associated ZYG-1 levels. In this study, we investigated ZYG-1 as a potential substrate of CK2 and the functional impact of ZYG-1 phosphorylation on centrosome assembly. First, we show that CK2 directly phosphorylates ZYG-1 in vitro and physically interacts with ZYG-1 in vivo. Intriguingly, depleting CK2 or blocking ZYG-1 phosphorylation at putative CK2 target sites leads to centrosome amplification. In the non-phosphorylatable (NP)-ZYG-1 mutant embryo, the overall levels of ZYG-1 are elevated, leading to an increase in centrosomal ZYG-1 and downstream factors, providing a possible mechanism of the NP-ZYG-1 mutation to drive centrosome amplification. Moreover, inhibiting the 26S proteasome blocks degradation of the phospho-mimetic (PM)-ZYG-1, while the NP-ZYG-1 mutant shows partial resistance to proteasomal degradation. Our findings suggest that site-specific phosphorylation of ZYG-1, partly mediated by CK2, controls ZYG-1 levels via proteasomal degradation, limiting centrosome number. We provide a mechanism linking CK2 kinase activity to centrosome duplication through direct phosphorylation of ZYG-1, which is critical for the integrity of centrosome number.
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Affiliation(s)
| | - Nahyun Yim
- Department of Biological Sciences, Oakland University, MI, USA
| | - Joseph DiPanni
- Department of Biological Sciences, Oakland University, MI, USA
| | - Brandon Sebou
- Department of Biological Sciences, Oakland University, MI, USA
| | - Blake Shaffou
- Department of Biological Sciences, Oakland University, MI, USA
| | - Evan Cramer
- Department of Chemistry, Oakland University, MI, USA
| | - Colin Wu
- Department of Chemistry, Oakland University, MI, USA
| | - Megan Kabara
- Department of Biological Sciences, Oakland University, MI, USA
- University of Connecticut School of Medicine, Office of Graduate Medical Education, Farmington, CT, USA
| | - Mi Hye Song
- Department of Biological Sciences, Oakland University, MI, USA
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4
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Kalous J, Aleshkina D. Multiple Roles of PLK1 in Mitosis and Meiosis. Cells 2023; 12:cells12010187. [PMID: 36611980 PMCID: PMC9818836 DOI: 10.3390/cells12010187] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/22/2022] [Accepted: 12/23/2022] [Indexed: 01/05/2023] Open
Abstract
Cells are equipped with a diverse network of signaling and regulatory proteins that function as cell cycle regulators and checkpoint proteins to ensure the proper progression of cell division. A key regulator of cell division is polo-like kinase 1 (PLK1), a member of the serine/threonine kinase family that plays an important role in regulating the mitotic and meiotic cell cycle. The phosphorylation of specific substrates mediated by PLK1 controls nuclear envelope breakdown (NEBD), centrosome maturation, proper spindle assembly, chromosome segregation, and cytokinesis. In mammalian oogenesis, PLK1 is essential for resuming meiosis before ovulation and for establishing the meiotic spindle. Among other potential roles, PLK1 regulates the localized translation of spindle-enriched mRNAs by phosphorylating and thereby inhibiting the translational repressor 4E-BP1, a downstream target of the mTOR (mammalian target of rapamycin) pathway. In this review, we summarize the functions of PLK1 in mitosis, meiosis, and cytokinesis and focus on the role of PLK1 in regulating mRNA translation. However, knowledge of the role of PLK1 in the regulation of meiosis remains limited.
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5
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Panchal NK, Mohanty S, Prince SE. NIMA-related kinase-6 (NEK6) as an executable target in cancer. CLINICAL & TRANSLATIONAL ONCOLOGY : OFFICIAL PUBLICATION OF THE FEDERATION OF SPANISH ONCOLOGY SOCIETIES AND OF THE NATIONAL CANCER INSTITUTE OF MEXICO 2023; 25:66-77. [PMID: 36074296 DOI: 10.1007/s12094-022-02926-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 08/09/2022] [Indexed: 01/07/2023]
Abstract
Cancer is a disease that develops when cells begin to divide uncontrollably and spreads to other parts of the body. Proliferation and invasion of cancerous cells are generally known to be influenced by cell cycle-related proteins in human malignancies. Therefore, in this review, we have emphasized on the serine/threonine kinase named NEK6. NEK6 is been deliberated to play a critical role in mitosis progression that includes mitotic spindle formation, metaphase to anaphase transition, and centrosome separation. Moreover, it has a mechanistic role in DNA repair and can cause apoptosis when inhibited. Past studies have connected NEK6 protein expression to cancer cell senescence. Besides, there are reports relating NEK6 to a range of malignancies including breast, lung, ovarian, prostate, kidney, liver, and others. Given its significance, this review attempts to describe the structural and functional aspects of NEK6 in various cellular processes, as well as how it is linked to different forms of cancer. Lastly, we have accentuated, on some of the plausible inhibitors that have been explored against NEK6 overexpression.
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Affiliation(s)
- Nagesh Kishan Panchal
- Department of Biomedical Sciences, School of Biosciences and Technology, Vellore Institute of Technology, Vellore, 632014, India
| | - Shruti Mohanty
- Department of Biomedical Sciences, School of Biosciences and Technology, Vellore Institute of Technology, Vellore, 632014, India
| | - Sabina Evan Prince
- Department of Biomedical Sciences, School of Biosciences and Technology, Vellore Institute of Technology, Vellore, 632014, India.
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6
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Vázquez-Blomquist D, Hardy-Sosa A, Baez SC, Besada V, Palomares S, Guirola O, Ramos Y, Wiśniewski JR, González LJ, Bello-Rivero I. Proteomics and Phospho-Proteomics Profiling of the Co-Formulation of Type I and II Interferons, HeberFERON, in the Glioblastoma-Derived Cell Line U-87 MG. Cells 2022; 11:cells11244068. [PMID: 36552831 PMCID: PMC9776974 DOI: 10.3390/cells11244068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 12/09/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022] Open
Abstract
HeberFERON, a co-formulation of Interferon (IFN)-α2b and IFN-γ, has effects on skin cancer and other solid tumors. It has antiproliferative effects over glioblastoma multiform (GBM) clones and cultured cell lines, including U-87 MG. Here, we report the first label-free quantitative proteomic and phospho-proteomic analyses to evaluate changes induced by HeberFERON after 72 h incubation of U-87 MG that can explain the effect on cellular proliferation. LC-MS/MS, functional enrichment and networking analysis were performed. We identified 7627 proteins; 122 and 211 were down- and up-regulated by HeberFERON (fold change > 2; p < 0.05), respectively. We identified 23,549 peptides (5692 proteins) and 8900 phospho-peptides; 523 of these phospho-peptides (359 proteins) were differentially modified. Proteomic enrichment showed IFN signaling and its control, direct and indirect antiviral mechanisms were the main modulated processes. Phospho-proteome enrichment displayed the cell cycle as one of the most commonly targeted events together with cytoskeleton organization; translation/RNA splicing, autophagy and DNA repair, as represented biological processes. There is a high interconnection of phosphoproteins in a molecular network; mTOR occupies a centric hub with interactions with translation machinery, cytoskeleton and autophagy components. Novel phosphosites and others with unknown biological functionality in key players in the aforementioned processes were regulated by HeberFERON and involved CDK and ERK kinases. These findings open new experimental hypotheses regarding HeberFERON action. The results obtained contribute to a better understanding of HeberFERON effector mechanisms in the context of GBM treatment.
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Affiliation(s)
- Dania Vázquez-Blomquist
- Pharmacogenomic Group, Department of System Biology, Biomedical Research Division, Center for Genetic Engineering and Biotechnology, Havana 10600, Cuba
- Correspondence:
| | | | - Saiyet C. Baez
- Département de Neurosciences, Université de Montréal, Montréal, QC H2L0A9, Canada
| | - Vladimir Besada
- Proteomics Group, Department of System Biology, Biomedical Research Division, Center for Genetic Engineering and Biotechnology, Havana 10600, Cuba
| | - Sucel Palomares
- Proteomics Group, Department of System Biology, Biomedical Research Division, Center for Genetic Engineering and Biotechnology, Havana 10600, Cuba
| | - Osmany Guirola
- Proteomics Group, Department of System Biology, Biomedical Research Division, Center for Genetic Engineering and Biotechnology, Havana 10600, Cuba
| | - Yassel Ramos
- Proteomics Group, Department of System Biology, Biomedical Research Division, Center for Genetic Engineering and Biotechnology, Havana 10600, Cuba
| | - Jacek R. Wiśniewski
- Biochemical Proteomics Group, Department of Proteomics and Signal Transduction, Max-Planck Institute of Biochemistry, 82152 Munich, Germany
| | - Luis Javier González
- Proteomics Group, Department of System Biology, Biomedical Research Division, Center for Genetic Engineering and Biotechnology, Havana 10600, Cuba
| | - Iraldo Bello-Rivero
- Clinical Assays Direction, Center for Genetic Engineering and Biotechnology, Havana 10600, Cuba
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7
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Archambault V, Li J, Emond-Fraser V, Larouche M. Dephosphorylation in nuclear reassembly after mitosis. Front Cell Dev Biol 2022; 10:1012768. [PMID: 36268509 PMCID: PMC9576876 DOI: 10.3389/fcell.2022.1012768] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 08/31/2022] [Indexed: 11/13/2022] Open
Abstract
In most animal cell types, the interphase nucleus is largely disassembled during mitotic entry. The nuclear envelope breaks down and chromosomes are compacted into separated masses. Chromatin organization is also mostly lost and kinetochores assemble on centromeres. Mitotic protein kinases play several roles in inducing these transformations by phosphorylating multiple effector proteins. In many of these events, the mechanistic consequences of phosphorylation have been characterized. In comparison, how the nucleus reassembles at the end of mitosis is less well understood in mechanistic terms. In recent years, much progress has been made in deciphering how dephosphorylation of several effector proteins promotes nuclear envelope reassembly, chromosome decondensation, kinetochore disassembly and interphase chromatin organization. The precise roles of protein phosphatases in this process, in particular of the PP1 and PP2A groups, are emerging. Moreover, how these enzymes are temporally and spatially regulated to ensure that nuclear reassembly progresses in a coordinated manner has been partly uncovered. This review provides a global view of nuclear reassembly with a focus on the roles of dephosphorylation events. It also identifies important open questions and proposes hypotheses.
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Affiliation(s)
- Vincent Archambault
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
- Département de Biochimie et Médecine Moléculaire, Université de Montréal, Montréal, QC, Canada
- *Correspondence: Vincent Archambault,
| | - Jingjing Li
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
- Département de Biochimie et Médecine Moléculaire, Université de Montréal, Montréal, QC, Canada
| | - Virginie Emond-Fraser
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
- Département de Biochimie et Médecine Moléculaire, Université de Montréal, Montréal, QC, Canada
| | - Myreille Larouche
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
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8
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Yoshino Y, Fang Z, Qi H, Kobayashi A, Chiba N. Dysregulation of the centrosome induced by BRCA1 deficiency contributes to tissue-specific carcinogenesis. Cancer Sci 2021; 112:1679-1687. [PMID: 33606355 PMCID: PMC8088922 DOI: 10.1111/cas.14859] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 02/11/2021] [Accepted: 02/16/2021] [Indexed: 12/12/2022] Open
Abstract
Alterations in breast cancer gene 1 (BRCA1), a tumor suppressor gene, increase the risk of breast and ovarian cancers. BRCA1 forms a heterodimer with BRCA1-associated RING domain protein 1 (BARD1) and functions in multiple cellular processes, including DNA repair and centrosome regulation. BRCA1 acts as a tumor suppressor by promoting homologous recombination (HR) repair, and alterations in BRCA1 cause HR deficiency, not only in breast and ovarian tissues but also in other tissues. The molecular mechanisms underlying BRCA1 alteration-induced carcinogenesis remain unclear. Centrosomes are the major microtubule-organizing centers and function in bipolar spindle formation. The regulation of centrosome number is critical for chromosome segregation in mitosis, which maintains genomic stability. BRCA1/BARD1 function in centrosome regulation together with Obg-like ATPase (OLA1) and receptor for activating protein C kinase 1 (RACK1). Cancer-derived variants of BRCA1, BARD1, OLA1, and RACK1 do not interact, and aberrant expression of these proteins results in abnormal centrosome duplication in mammary-derived cells, and rarely in other cell types. RACK1 is involved in centriole duplication in the S phase by promoting polo-like kinase 1 activation by Aurora A, which is critical for centrosome duplication. Centriole number is higher in cells derived from mammary tissues compared with in those derived from other tissues, suggesting that tissue-specific centrosome characterization may shed light on the tissue specificity of BRCA1-associated carcinogenesis. Here, we explored the role of the BRCA1-containing complex in centrosome regulation and the effect of its deficiency on tissue-specific carcinogenesis.
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Affiliation(s)
- Yuki Yoshino
- Department of Cancer BiologyInstitute of Aging, Development, and CancerTohoku UniversitySendaiJapan
- Laboratory of Cancer BiologyGraduate School of Life SciencesTohoku UniversitySendaiJapan
- Department of Cancer BiologyTohoku University Graduate School of MedicineSendaiJapan
| | - Zhenzhou Fang
- Department of Cancer BiologyInstitute of Aging, Development, and CancerTohoku UniversitySendaiJapan
- Department of Cancer BiologyTohoku University Graduate School of MedicineSendaiJapan
| | - Huicheng Qi
- Department of Cancer BiologyInstitute of Aging, Development, and CancerTohoku UniversitySendaiJapan
- Department of Cancer BiologyTohoku University Graduate School of MedicineSendaiJapan
| | - Akihiro Kobayashi
- Department of Cancer BiologyInstitute of Aging, Development, and CancerTohoku UniversitySendaiJapan
- Department of Cancer BiologyTohoku University Graduate School of MedicineSendaiJapan
| | - Natsuko Chiba
- Department of Cancer BiologyInstitute of Aging, Development, and CancerTohoku UniversitySendaiJapan
- Laboratory of Cancer BiologyGraduate School of Life SciencesTohoku UniversitySendaiJapan
- Department of Cancer BiologyTohoku University Graduate School of MedicineSendaiJapan
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9
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Guo X, Ramirez I, Garcia YA, Velasquez EF, Gholkar AA, Cohn W, Whitelegge JP, Tofig B, Damoiseaux R, Torres JZ. DUSP7 regulates the activity of ERK2 to promote proper chromosome alignment during cell division. J Biol Chem 2021; 296:100676. [PMID: 33865857 PMCID: PMC8131738 DOI: 10.1016/j.jbc.2021.100676] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 04/10/2021] [Accepted: 04/14/2021] [Indexed: 12/20/2022] Open
Abstract
Human cell division is a highly regulated process that relies on the accurate capture and movement of chromosomes to the metaphase plate. Errors in the fidelity of chromosome congression and alignment can lead to improper chromosome segregation, which is correlated with aneuploidy and tumorigenesis. These processes are known to be regulated by extracellular signal-regulated kinase 2 (ERK2) in other species, but the role of ERK2 in mitosis in mammals remains unclear. Here, we have identified the dual-specificity phosphatase 7 (DUSP7), known to display selectivity for ERK2, as important in regulating chromosome alignment. During mitosis, DUSP7 bound to ERK2 and regulated the abundance of active phospho-ERK2 through its phosphatase activity. Overexpression of DUSP7, but not catalytically inactive mutants, led to a decrease in the levels of phospho-ERK2 and mitotic chromosome misalignment, while knockdown of DUSP7 also led to defective chromosome congression that resulted in a prolonged mitosis. Consistently, knockdown or chemical inhibition of ERK2 or chemical inhibition of the MEK kinase that phosphorylates ERK2 led to chromosome alignment defects. Our results support a model wherein MEK-mediated phosphorylation and DUSP7-mediated dephosphorylation regulate the levels of active phospho-ERK2 to promote proper cell division.
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Affiliation(s)
- Xiao Guo
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California, USA
| | - Ivan Ramirez
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California, USA
| | - Yenni A Garcia
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California, USA
| | - Erick F Velasquez
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California, USA
| | - Ankur A Gholkar
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California, USA
| | - Whitaker Cohn
- Pasarow Mass Spectrometry Laboratory, The Jane and Terry Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| | - Julian P Whitelegge
- Pasarow Mass Spectrometry Laboratory, The Jane and Terry Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California, Los Angeles, California, USA; Molecular Biology Institute, University of California, Los Angeles, California, USA; Jonsson Comprehensive Cancer Center, University of California, Los Angeles, California, USA
| | - Bobby Tofig
- California NanoSystems Institute, University of California, Los Angeles, California, USA
| | - Robert Damoiseaux
- California NanoSystems Institute, University of California, Los Angeles, California, USA; Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California, USA
| | - Jorge Z Torres
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California, USA; Molecular Biology Institute, University of California, Los Angeles, California, USA; Jonsson Comprehensive Cancer Center, University of California, Los Angeles, California, USA.
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10
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Ong JY, Bradley MC, Torres JZ. Phospho-regulation of mitotic spindle assembly. Cytoskeleton (Hoboken) 2020; 77:558-578. [PMID: 33280275 PMCID: PMC7898546 DOI: 10.1002/cm.21649] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 10/08/2020] [Accepted: 12/02/2020] [Indexed: 12/23/2022]
Abstract
The assembly of the bipolar mitotic spindle requires the careful orchestration of a myriad of enzyme activities like protein posttranslational modifications. Among these, phosphorylation has arisen as the principle mode for spatially and temporally activating the proteins involved in early mitotic spindle assembly processes. Here, we review key kinases, phosphatases, and phosphorylation events that regulate critical aspects of these processes. We highlight key phosphorylation substrates that are important for ensuring the fidelity of centriole duplication, centrosome maturation, and the establishment of the bipolar spindle. We also highlight techniques used to understand kinase-substrate relationships and to study phosphorylation events. We conclude with perspectives on the field of posttranslational modifications in early mitotic spindle assembly.
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Affiliation(s)
- Joseph Y Ong
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California, USA
| | - Michelle C Bradley
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California, USA
| | - Jorge Z Torres
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California, USA.,Molecular Biology Institute, University of California, Los Angeles, California, USA.,Jonsson Comprehensive Cancer Center, University of California, Los Angeles, California, USA
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