1
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Rowland RJ, Korolchuk S, Salamina M, Tatum NJ, Ault JR, Hart S, Turkenburg JP, Blaza JN, Noble MEM, Endicott JA. Cryo-EM structure of the CDK2-cyclin A-CDC25A complex. Nat Commun 2024; 15:6807. [PMID: 39122719 PMCID: PMC11316097 DOI: 10.1038/s41467-024-51135-w] [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: 09/29/2023] [Accepted: 07/22/2024] [Indexed: 08/12/2024] Open
Abstract
The cell division cycle 25 phosphatases CDC25A, B and C regulate cell cycle transitions by dephosphorylating residues in the conserved glycine-rich loop of CDKs to activate their activity. Here, we present the cryo-EM structure of CDK2-cyclin A in complex with CDC25A at 2.7 Å resolution, providing a detailed structural analysis of the overall complex architecture and key protein-protein interactions that underpin this 86 kDa complex. We further identify a CDC25A C-terminal helix that is critical for complex formation. Sequence conservation analysis suggests CDK1/2-cyclin A, CDK1-cyclin B and CDK2/3-cyclin E are suitable binding partners for CDC25A, whilst CDK4/6-cyclin D complexes appear unlikely substrates. A comparative structural analysis of CDK-containing complexes also confirms the functional importance of the conserved CDK1/2 GDSEID motif. This structure improves our understanding of the roles of CDC25 phosphatases in CDK regulation and may inform the development of CDC25-targeting anticancer strategies.
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Affiliation(s)
- Rhianna J Rowland
- Translational and Clinical Research Institute, Newcastle University Centre for Cancer, Newcastle University, Paul O'Gorman Building, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Svitlana Korolchuk
- Translational and Clinical Research Institute, Newcastle University Centre for Cancer, Newcastle University, Paul O'Gorman Building, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
- Fujifilm, Belasis Ave, Stockton-on-Tees, Billingham, TS23 1LH, UK
| | - Marco Salamina
- Translational and Clinical Research Institute, Newcastle University Centre for Cancer, Newcastle University, Paul O'Gorman Building, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
- Evotec (UK) Ltd., Milton, Abingdon, OX14 4RZ, UK
| | - Natalie J Tatum
- Translational and Clinical Research Institute, Newcastle University Centre for Cancer, Newcastle University, Paul O'Gorman Building, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - James R Ault
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Sam Hart
- York Structural Biology Laboratory and York Biomedical Research Institute, Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK
| | - Johan P Turkenburg
- York Structural Biology Laboratory and York Biomedical Research Institute, Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK
| | - James N Blaza
- York Structural Biology Laboratory and York Biomedical Research Institute, Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK
| | - Martin E M Noble
- Translational and Clinical Research Institute, Newcastle University Centre for Cancer, Newcastle University, Paul O'Gorman Building, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK.
| | - Jane A Endicott
- Translational and Clinical Research Institute, Newcastle University Centre for Cancer, Newcastle University, Paul O'Gorman Building, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK.
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2
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Chen Y, Li X, Yang M, Liu SB. Research progress on morphology and mechanism of programmed cell death. Cell Death Dis 2024; 15:327. [PMID: 38729953 PMCID: PMC11087523 DOI: 10.1038/s41419-024-06712-8] [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: 12/18/2023] [Revised: 04/17/2024] [Accepted: 04/29/2024] [Indexed: 05/12/2024]
Abstract
Programmed cell death (PCD) is a basic process of life that is closely related to the growth, development, aging and disease of organisms and is one of the hotspots of life science research today. PCD is a kind of genetic control, autonomous and orderly important cell death that involves the activation, expression, and regulation of a series of genes. In recent years, with the deepening of research in this field, new mechanisms of multiple PCD pathways have been revealed. This article reviews and summarizes the multiple PCD pathways that have been discovered, analyses and compares the morphological characteristics and biomarkers of different types of PCD, and briefly discusses the role of various types of PCD in the diagnosis and treatment of different diseases, especially malignant tumors.
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Grants
- Jiangsu higher education institution innovative research team for science and technology (2021), Program of Jiangsu vocational college engineering technology research center (2023), Key technology progrom of Suzhou people’s livelihood technology projects (Grant No. SKY2021029), the Open Project of Jiangsu Biobank of Clinical Resources (TC2021B009), the Project of State Key Laboratory of Radiation Medicine and Protection, Soochow University, (No. GZK12023013), Programs of the Suzhou Vocational Health College (SZWZYTD202201), Qing‐Lan Project of Jiangsu Province in China (2021).
- Programs of the Suzhou Vocational Health College (szwzy 202210), Qing‐Lan Project of Jiangsu Province in China (2022).
- the Project of State Key Laboratory of Radiation Medicine and Protection, Soochow University, (No. GZK12023013)
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Affiliation(s)
- Yao Chen
- Suzhou Key Laboratory of Medical Biotechnology, Suzhou Vocational Health College, Suzhou, China
| | - Xiaohua Li
- Department of Thyroid and Breast Surgery, Wuzhong People's Hospital of Suzhou City, Suzhou, China
| | - Minfeng Yang
- School of Public Health, Nantong University, Nantong, 226019, China.
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China.
| | - Song-Bai Liu
- Suzhou Key Laboratory of Medical Biotechnology, Suzhou Vocational Health College, Suzhou, China.
- State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, 215123, China.
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3
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Basier C, Nurse P. TOR regulates variability of protein synthesis rates. EMBO J 2024; 43:1618-1633. [PMID: 38499788 PMCID: PMC11021518 DOI: 10.1038/s44318-024-00075-8] [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: 10/23/2023] [Revised: 02/20/2024] [Accepted: 02/23/2024] [Indexed: 03/20/2024] Open
Abstract
Cellular processes are subject to inherent variability, but the extent to which cells can regulate this variability has received little investigation. Here, we explore the characteristics of the rate of cellular protein synthesis in single cells of the eukaryote fission yeast. Strikingly, this rate is highly variable despite protein synthesis being dependent on hundreds of reactions which might be expected to average out at the overall cellular level. The rate is variable over short time scales, and exhibits homoeostatic behaviour at the population level. Cells can regulate the level of variability through processes involving the TOR pathway, suggesting there is an optimal level of variability conferring a selective advantage. While this could be an example of bet-hedging, but we propose an alternative explanation: regulated 'loose' control of complex processes of overall cellular metabolism such as protein synthesis, may lead to this variability. This could ensure cells are fluid in control and agile in response to changing conditions, and may constitute a novel organisational principle of complex metabolic cellular systems.
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Affiliation(s)
- Clovis Basier
- Cell Cycle Laboratory, The Francis Crick Institute, London, NW1 1AT, UK.
| | - Paul Nurse
- Cell Cycle Laboratory, The Francis Crick Institute, London, NW1 1AT, UK
- Laboratory of Yeast Genetics and Cell Biology, Rockefeller University, New York, NY, 10065, USA
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4
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Sugiyama H, Goto Y, Kondo Y, Coudreuse D, Aoki K. Live-cell imaging defines a threshold in CDK activity at the G2/M transition. Dev Cell 2024; 59:545-557.e4. [PMID: 38228139 DOI: 10.1016/j.devcel.2023.12.014] [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: 04/12/2023] [Revised: 10/05/2023] [Accepted: 12/21/2023] [Indexed: 01/18/2024]
Abstract
Cyclin-dependent kinase (CDK) determines the temporal ordering of the cell cycle phases. However, despite significant progress in studying regulators of CDK and phosphorylation patterns of CDK substrates at the population level, it remains elusive how CDK regulators coordinately affect CDK activity at the single-cell level and how CDK controls the temporal order of cell cycle events. Here, we elucidate the dynamics of CDK activity in fission yeast and mammalian cells by developing a CDK activity biosensor, Eevee-spCDK. We find that although CDK activity does not necessarily correlate with cyclin levels, it converges to the same level around mitotic onset in several mutant backgrounds, including pom1Δ cells and wee1 or cdc25 overexpressing cells. These data provide direct evidence that cells enter the M phase when CDK activity reaches a high threshold, consistent with the quantitative model of cell cycle progression in fission yeast.
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Affiliation(s)
- Hironori Sugiyama
- Quantitative Biology Research Group, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan
| | - Yuhei Goto
- Quantitative Biology Research Group, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan; Division of Quantitative Biology, National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan; Basic Biology Program, Graduate Institute for Advanced Studies, SOKENDAI, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan
| | - Yohei Kondo
- Quantitative Biology Research Group, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan; Division of Quantitative Biology, National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan; Basic Biology Program, Graduate Institute for Advanced Studies, SOKENDAI, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan
| | - Damien Coudreuse
- Institute of Biochemistry and Cellular Genetics, UMR 5095, CNRS, Bordeaux University, 33077 Bordeaux, France
| | - Kazuhiro Aoki
- Quantitative Biology Research Group, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan; Division of Quantitative Biology, National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan; Basic Biology Program, Graduate Institute for Advanced Studies, SOKENDAI, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan.
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5
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Dakilah I, Harb A, Abu-Gharbieh E, El-Huneidi W, Taneera J, Hamoudi R, Semreen MH, Bustanji Y. Potential of CDC25 phosphatases in cancer research and treatment: key to precision medicine. Front Pharmacol 2024; 15:1324001. [PMID: 38313315 PMCID: PMC10834672 DOI: 10.3389/fphar.2024.1324001] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 01/04/2024] [Indexed: 02/06/2024] Open
Abstract
The global burden of cancer continues to rise, underscoring the urgency of developing more effective and precisely targeted therapies. This comprehensive review explores the confluence of precision medicine and CDC25 phosphatases in the context of cancer research. Precision medicine, alternatively referred to as customized medicine, aims to customize medical interventions by taking into account the genetic, genomic, and epigenetic characteristics of individual patients. The identification of particular genetic and molecular drivers driving cancer helps both diagnostic accuracy and treatment selection. Precision medicine utilizes sophisticated technology such as genome sequencing and bioinformatics to elucidate genetic differences that underlie the proliferation of cancer cells, hence facilitating the development of customized therapeutic interventions. CDC25 phosphatases, which play a crucial role in governing the progression of the cell cycle, have garnered significant attention as potential targets for cancer treatment. The dysregulation of CDC25 is a characteristic feature observed in various types of malignancies, hence classifying them as proto-oncogenes. The proteins in question, which operate as phosphatases, play a role in the activation of Cyclin-dependent kinases (CDKs), so promoting the advancement of the cell cycle. CDC25 inhibitors demonstrate potential as therapeutic drugs for cancer treatment by specifically blocking the activity of CDKs and modulating the cell cycle in malignant cells. In brief, precision medicine presents a potentially fruitful option for augmenting cancer research, diagnosis, and treatment, with an emphasis on individualized care predicated upon patients' genetic and molecular profiles. The review highlights the significance of CDC25 phosphatases in the advancement of cancer and identifies them as promising candidates for therapeutic intervention. This statement underscores the significance of doing thorough molecular profiling in order to uncover the complex molecular characteristics of cancer cells.
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Affiliation(s)
- Ibraheem Dakilah
- Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah, United Arab Emirates
| | - Amani Harb
- Department of Basic Sciences, Faculty of Arts and Sciences, Al-Ahliyya Amman University, Amman, Jordan
| | - Eman Abu-Gharbieh
- Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah, United Arab Emirates
- College of Medicine, University of Sharjah, Sharjah, United Arab Emirates
| | - Waseem El-Huneidi
- Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah, United Arab Emirates
- College of Medicine, University of Sharjah, Sharjah, United Arab Emirates
| | - Jalal Taneera
- Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah, United Arab Emirates
- College of Medicine, University of Sharjah, Sharjah, United Arab Emirates
| | - Rifat Hamoudi
- Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah, United Arab Emirates
- College of Medicine, University of Sharjah, Sharjah, United Arab Emirates
- Division of Surgery and Interventional Science, University College London, London, United Kingdom
| | - Mohammed H Semreen
- College of Pharmacy, University of Sharjah, Sharjah, United Arab Emirates
| | - Yasser Bustanji
- Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah, United Arab Emirates
- College of Medicine, University of Sharjah, Sharjah, United Arab Emirates
- School of Pharmacy, The University of Jordan, Amman, Jordan
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6
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Mallipattu SK. The loss of profilin1 is catastrophic to podocytes. J Clin Invest 2023; 133:e175594. [PMID: 38099501 PMCID: PMC10721137 DOI: 10.1172/jci175594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2023] Open
Abstract
Profilin1 belongs to a family of small monomeric actin-binding proteins with diverse roles in fundamental actin-dependent cellular processes required for cell survival. Podocytes are postmitotic visceral epithelial cells critical for the structure and function of the kidney filtration barrier. There is emerging evidence that the actin-related mode of cell death known as mitotic catastrophe is an important pathway involved in podocyte loss. In this issue of the JCI, Tian, Pedigo, and colleagues demonstrate that profilin1 deficiency in podocytes triggered cell cycle reentry, resulting in abortive cytokinesis with a loss in ribosomal RNA processing that leads to podocyte loss and glomerulosclerosis. This study demonstrates the essential role of actin dynamics in mediating this fundamental mode of podocyte cell death.
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7
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Tian X, Pedigo CE, Li K, Ma X, Bunda P, Pell J, Lek A, Gu J, Zhang Y, Medina Rangel PX, Li W, Schwartze E, Nagata S, Lerner G, Perincheri S, Priyadarshini A, Zhao H, Lek M, Menon MC, Fu R, Ishibe S. Profilin1 is required for prevention of mitotic catastrophe in murine and human glomerular diseases. J Clin Invest 2023; 133:e171237. [PMID: 37847555 PMCID: PMC10721156 DOI: 10.1172/jci171237] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 10/12/2023] [Indexed: 10/18/2023] Open
Abstract
The progression of proteinuric kidney diseases is associated with podocyte loss, but the mechanisms underlying this process remain unclear. Podocytes reenter the cell cycle to repair double-stranded DNA breaks. However, unsuccessful repair can result in podocytes crossing the G1/S checkpoint and undergoing abortive cytokinesis. In this study, we identified Pfn1 as indispensable in maintaining glomerular integrity - its tissue-specific loss in mouse podocytes resulted in severe proteinuria and kidney failure. Our results suggest that this phenotype is due to podocyte mitotic catastrophe (MC), characterized histologically and ultrastructurally by abundant multinucleated cells, irregular nuclei, and mitotic spindles. Podocyte cell cycle reentry was identified using FUCCI2aR mice, and we observed altered expression of cell-cycle associated proteins, such as p21, p53, cyclin B1, and cyclin D1. Podocyte-specific translating ribosome affinity purification and RNA-Seq revealed the downregulation of ribosomal RNA-processing 8 (Rrp8). Overexpression of Rrp8 in Pfn1-KO podocytes partially rescued the phenotype in vitro. Clinical and ultrastructural tomographic analysis of patients with diverse proteinuric kidney diseases further validated the presence of MC podocytes and reduction in podocyte PFN1 expression within kidney tissues. These results suggest that profilin1 is essential in regulating the podocyte cell cycle and its disruption leads to MC and subsequent podocyte loss.
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Affiliation(s)
- Xuefei Tian
- Section of Nephrology, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut, USA
| | - Christopher E. Pedigo
- Section of Nephrology, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut, USA
| | - Ke Li
- Department of Nephrology, Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Xiaotao Ma
- Department of Nephrology, Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Patricia Bunda
- Section of Nephrology, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut, USA
| | - John Pell
- Section of Nephrology, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut, USA
| | | | - Jianlei Gu
- Department of Biostatistics, Yale School of Public Health, New Haven, Connecticut, USA
| | - Yan Zhang
- Bioinformation Department, Suzhou SITRI Institute of Immunology Co. Ltd., Suzhou, Jiangsu, China
| | - Paulina X. Medina Rangel
- Section of Nephrology, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut, USA
| | - Wei Li
- Section of Nephrology, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut, USA
| | - Eike Schwartze
- Section of Nephrology, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut, USA
| | - Soichiro Nagata
- Section of Nephrology, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut, USA
| | - Gabriel Lerner
- Departments of Surgical Pathology and Laboratory Medicine, Yale School of Medicine, New Haven, Connecticut, USA
| | - Sudhir Perincheri
- Departments of Surgical Pathology and Laboratory Medicine, Yale School of Medicine, New Haven, Connecticut, USA
| | - Anupama Priyadarshini
- Section of Nephrology, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut, USA
| | - Hongyu Zhao
- Department of Biostatistics, Yale School of Public Health, New Haven, Connecticut, USA
| | | | - Madhav C. Menon
- Section of Nephrology, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut, USA
| | - Rongguo Fu
- Department of Nephrology, Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Shuta Ishibe
- Section of Nephrology, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut, USA
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8
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Saunders H, Dias WB, Slawson C. Growing and dividing: how O-GlcNAcylation leads the way. J Biol Chem 2023; 299:105330. [PMID: 37820866 PMCID: PMC10641531 DOI: 10.1016/j.jbc.2023.105330] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 09/27/2023] [Accepted: 10/02/2023] [Indexed: 10/13/2023] Open
Abstract
Cell cycle errors can lead to mutations, chromosomal instability, or death; thus, the precise control of cell cycle progression is essential for viability. The nutrient-sensing posttranslational modification, O-GlcNAc, regulates the cell cycle allowing one central control point directing progression of the cell cycle. O-GlcNAc is a single N-acetylglucosamine sugar modification to intracellular proteins that is dynamically added and removed by O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA), respectively. These enzymes act as a rheostat to fine-tune protein function in response to a plethora of stimuli from nutrients to hormones. O-GlcNAc modulates mitogenic growth signaling, senses nutrient flux through the hexosamine biosynthetic pathway, and coordinates with other nutrient-sensing enzymes to progress cells through Gap phase 1 (G1). At the G1/S transition, O-GlcNAc modulates checkpoint control, while in S Phase, O-GlcNAcylation coordinates the replication fork. DNA replication errors activate O-GlcNAcylation to control the function of the tumor-suppressor p53 at Gap Phase 2 (G2). Finally, in mitosis (M phase), O-GlcNAc controls M phase progression and the organization of the mitotic spindle and midbody. Critical for M phase control is the interplay between OGT and OGA with mitotic kinases. Importantly, disruptions in OGT and OGA activity induce M phase defects and aneuploidy. These data point to an essential role for the O-GlcNAc rheostat in regulating cell division. In this review, we highlight O-GlcNAc nutrient sensing regulating G1, O-GlcNAc control of DNA replication and repair, and finally, O-GlcNAc organization of mitotic progression and spindle dynamics.
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Affiliation(s)
- Harmony Saunders
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Wagner B Dias
- Federal University of Rio De Janeiro, Rio De Janeiro, Brazil; Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Chad Slawson
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, Kansas, USA.
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9
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Miller KE, Vargas-Garcia C, Singh A, Moseley JB. The fission yeast cell size control system integrates pathways measuring cell surface area, volume, and time. Curr Biol 2023; 33:3312-3324.e7. [PMID: 37463585 PMCID: PMC10529673 DOI: 10.1016/j.cub.2023.06.054] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 06/01/2023] [Accepted: 06/20/2023] [Indexed: 07/20/2023]
Abstract
Eukaryotic cells tightly control their size, but the relevant aspect of size is unknown in most cases. Fission yeast divide at a threshold cell surface area (SA) due, in part, to the protein kinase Cdr2. We find that fission yeast cells only divide by SA under a size threshold. Mutants that divide at a larger size shift to volume-based divisions. Diploid cells divide at a larger size than haploid cells do, but they maintain SA-based divisions, and this indicates that the size threshold for changing from surface-area-based to volume-based control is set by ploidy. Within this size control system, we found that the mitotic activator Cdc25 accumulates like a volume-based sizer molecule, whereas the mitotic cyclin Cdc13 accumulates in the nucleus as a timer. We propose an integrated model for cell size control based on multiple signaling pathways that report on distinct aspects of cell size and growth, including cell SA (Cdr2), cell volume (Cdc25), and time (Cdc13). Combined modeling and experiments show how this system can generate both sizer- and adder-like properties.
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Affiliation(s)
- Kristi E Miller
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Cesar Vargas-Garcia
- Grupo de Investigación en Sistemas Agropecuarios Sostenibles, Corporación Colombiana de Investigación Agropecuaria - AGROSAVIA, Bogotá 250047, Colombia
| | - Abhyudai Singh
- Department of Electrical and Computer Engineering, University of Delaware, Newark, DE 19716, USA
| | - James B Moseley
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA.
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10
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Bradley RA, Wolff ID, Cohen PE, Gray S. Dynamic regulatory phosphorylation of mouse CDK2 occurs during meiotic prophase I. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.24.550435. [PMID: 37546989 PMCID: PMC10402020 DOI: 10.1101/2023.07.24.550435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
During prophase I of meiosis, DNA double-strand breaks form throughout the genome, with a subset repairing as crossover events, enabling the accurate segregation of homologous chromosomes during the first meiotic division. The mechanism by which DSBs become selected to repair as crossovers is unknown, although the crossover positioning and levels in each cell indicate it is a highly regulated process. One of the proteins that localises to crossover sites is the serine/threonine cyclin-dependent kinase CDK2. Regulation of CDK2 occurs via phosphorylation at tyrosine 15 (Y15) and threonine 160 (T160) inhibiting and activating the kinase, respectively. In this study we use a combination of immunofluorescence staining on spread spermatocytes and fixed testis sections, and STA-PUT gravitational sedimentation to isolate cells at different developmental stages to further investigate the temporal phospho regulation of CDK2 during prophase I. Western blotting reveals differential levels of the two CDK2 isoforms (CDK233kDa and CDK239kDa) throughout prophase I, with inhibitory phosphorylation of CDK2 at Y15 occurring early in prophase I, localising to telomeres and diminishing as cells enter pachynema. Conversely, the activatory phosphorylation on T160 occurs later, specifically the CDK233kDa isoform, and T160 signal is detected in spermatogonia and pachytene spermatocytes, where it co-localises with the Class I crossover protein MLH3. Taken together, our data reveals intricate control of CDK2 both with regards to levels of the two CDK2 isoforms, and differential regulation via inhibitory and activatory phosphorylation.
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Affiliation(s)
- Rachel A. Bradley
- Department of Biomedical Sciences and Cornell Reproductive Sciences Center (CoRe), Cornell University, Ithaca, NY, 14853, United States of America
| | - Ian D. Wolff
- Department of Biomedical Sciences and Cornell Reproductive Sciences Center (CoRe), Cornell University, Ithaca, NY, 14853, United States of America
| | - Paula E. Cohen
- Department of Biomedical Sciences and Cornell Reproductive Sciences Center (CoRe), Cornell University, Ithaca, NY, 14853, United States of America
| | - Stephen Gray
- Queen’s Medical Centre, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, United Kingdom
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11
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Jain I, Tran PT. Prolongation of mitosis is associated with enhanced endogenous DNA damage in fission yeast. MICROPUBLICATION BIOLOGY 2023; 2023:10.17912/micropub.biology.000911. [PMID: 37521138 PMCID: PMC10375284 DOI: 10.17912/micropub.biology.000911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 07/13/2023] [Accepted: 07/12/2023] [Indexed: 08/01/2023]
Abstract
Mitosis is usually shorter than other phases of the cell cycle and maintains a consistent duration despite variations in cell size and spindle size. This suggests the existence of a compensatory mechanism that ensures a short duration, possibly as a protective measure against irreversible damage, such as DNA damage. To explore the link between prolonged mitosis and DNA damage, we develop a microscopy-based assay utilizing Rad52-GFP as a marker for mitotic DNA damage. Through this assay, we provide evidence that mutants with prolonged mitosis exhibit increased Rad52 puncta, indicating an elevation in endogenous DNA damage.
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Affiliation(s)
- Ishutesh Jain
- Institut Curie, PSL Université, Sorbonne Université, CNRS UMR 144, Paris 75005, France
- Simons Centre for the Study of Living Machines, National Centre for Biological Sciences - TIFR, Bangalore 560065, India
| | - Phong T. Tran
- Institut Curie, PSL Université, Sorbonne Université, CNRS UMR 144, Paris 75005, France
- University of Pennsylvania, Department of Cell and Developmental Biology, Philadelphia, PA 19104, USA
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12
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González-Martín E, Jiménez J, Tallada VA. BiFCo: visualizing cohesin assembly/disassembly cycle in living cells. Life Sci Alliance 2023; 6:e202301945. [PMID: 37160310 PMCID: PMC10172768 DOI: 10.26508/lsa.202301945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 04/13/2023] [Accepted: 04/17/2023] [Indexed: 05/11/2023] Open
Abstract
Cohesin is a highly conserved, ring-shaped protein complex found in all eukaryotes. It consists of at least two structural maintenance of chromosomes (SMC) proteins, SMC1 and SMC3 in humans (Psm1 and Psm3 in fission yeast), and the kleisin RAD21 (Rad21 in fission yeast). Mutations in its components or regulators can lead to genetic syndromes, known as cohesinopathies, and various types of cancer. Studies in several organisms have shown that only a small fraction of each subunit assembles into complexes, making it difficult to investigate dynamic chromatin loading and unloading using fluorescent fusions in vivo because of excess soluble components. In this study, we introduce bimolecular fluorescent cohesin (BiFCo), based on bimolecular fluorescent complementation in the fission yeast Schizosaccharomyces pombe BiFCo selectively excludes signals from individual proteins, enabling the monitoring of complex assembly and disassembly within a physiological context throughout the entire cell cycle in living cells. This versatile system can be expanded and adapted for various genetic backgrounds and other eukaryotic models, including human cells.
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Affiliation(s)
- Emilio González-Martín
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas-Junta de Andalucía, Seville, Spain
| | - Juan Jiménez
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas-Junta de Andalucía, Seville, Spain
| | - Víctor A Tallada
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas-Junta de Andalucía, Seville, Spain
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13
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Jain I, Rao M, Tran PT. Reliable and robust control of nucleus centering is contingent on nonequilibrium force patterns. iScience 2023; 26:106665. [PMID: 37182105 PMCID: PMC10173738 DOI: 10.1016/j.isci.2023.106665] [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: 07/18/2022] [Revised: 02/23/2023] [Accepted: 04/09/2023] [Indexed: 05/16/2023] Open
Abstract
Cell centers their division apparatus to ensure symmetric cell division, a challenging task when the governing dynamics is stochastic. Using fission yeast, we show that the patterning of nonequilibrium polymerization forces of microtubule (MT) bundles controls the precise localization of spindle pole body (SPB), and hence the division septum, at the onset of mitosis. We define two cellular objectives, reliability, the mean SPB position relative to the geometric center, and robustness, the variance of the SPB position, which are sensitive to genetic perturbations that change cell length, MT bundle number/orientation, and MT dynamics. We show that simultaneous control of reliability and robustness is required to minimize septum positioning error achieved by the wild type (WT). A stochastic model for the MT-based nucleus centering, with parameters measured directly or estimated using Bayesian inference, recapitulates the maximum fidelity of WT. Using this, we perform a sensitivity analysis of the parameters that control nuclear centering.
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Affiliation(s)
- Ishutesh Jain
- Institut Curie, PSL Universite, Sorbonne Universite, CNRS UMR 144, 75005 Paris, France
- Simons Centre for the Study of Living Machines, National Centre for Biological Sciences - TIFR, Bangalore 560065, India
| | - Madan Rao
- Simons Centre for the Study of Living Machines, National Centre for Biological Sciences - TIFR, Bangalore 560065, India
- Corresponding author
| | - Phong T. Tran
- Institut Curie, PSL Universite, Sorbonne Universite, CNRS UMR 144, 75005 Paris, France
- Department of Cell and Developmental Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
- Corresponding author
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14
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Pramanik SK, Sanphui P, Das AK, Banerji B, Biswas SC. Small-Molecule Cdc25A Inhibitors Protect Neuronal Cells from Death Evoked by NGF Deprivation and 6-Hydroxydopamine. ACS Chem Neurosci 2023; 14:1226-1237. [PMID: 36942687 DOI: 10.1021/acschemneuro.2c00474] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023] Open
Abstract
Alzheimer's disease (AD) and Parkinson's disease (PD) are the two most common neurodegenerative diseases that are presently incurable. There have been reports of aberrant activation of cell cycle pathways in neurodegenerative diseases. Previously, we have found that Cdc25A is activated in models of neurodegenerative diseases, including AD and PD. In the present study, we have synthesized a small library of molecules targeting Cdc25A and tested their neuroprotective potential in cellular models of neurodegeneration. The Buchwald reaction and amide coupling were crucial steps in synthesizing the Cdc25A-targeting molecules. Several of these small-molecule inhibitors significantly prevented neuronal cell death induced by nerve growth factor (NGF) deprivation as well as 6-hydroxydopamine (6-OHDA) treatment. Lack of NGF signaling leads to neuron death during development and has been associated with AD pathogenesis. The NGF receptor TrkA has been reported to be downregulated at the early stages of AD, and its reduction is linked to cognitive failure. 6-OHDA, a PD mimic, is a highly oxidizable dopamine analogue that can be taken up by the dopamine transporters in catecholaminergic neurons and can induce cell death by reactive oxygen species (ROS) generation. Some of our newly synthesized molecules inhibit Cdc25A phosphatase activity, block loss of mitochondrial activity, and inhibit caspase-3 activation caused by NGF deprivation and 6-OHDA. Hence, it may be proposed that Cdc25A inhibition could be a therapeutic possibility for neurodegenerative diseases and these Cdc25A inhibitors could be effective treatments for AD and PD.
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15
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Al-Rawi A, Kaye E, Korolchuk S, Endicott JA, Ly T. Cyclin A and Cks1 promote kinase consensus switching to non-proline-directed CDK1 phosphorylation. Cell Rep 2023; 42:112139. [PMID: 36840943 DOI: 10.1016/j.celrep.2023.112139] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 11/17/2022] [Accepted: 02/02/2023] [Indexed: 02/26/2023] Open
Abstract
Ordered protein phosphorylation by CDKs is a key mechanism for regulating the cell cycle. How temporal order is enforced in mammalian cells remains unclear. Using a fixed cell kinase assay and phosphoproteomics, we show how CDK1 activity and non-catalytic CDK1 subunits contribute to the choice of substrate and site of phosphorylation. Increases in CDK1 activity alter substrate choice, with intermediate- and low-sensitivity CDK1 substrates enriched in DNA replication and mitotic functions, respectively. This activity dependence is shared between Cyclin A- and Cyclin B-CDK1. Cks1 has a proteome-wide role as an enhancer of multisite CDK1 phosphorylation. Contrary to the model of CDK1 as an exclusively proline-directed kinase, we show that Cyclin A and Cks1 enhance non-proline-directed phosphorylation, preferably on sites with a +3 lysine residue. Indeed, 70% of cell-cycle-regulated phosphorylations, where the kinase carrying out this modification has not been identified, are non-proline-directed CDK1 sites.
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Affiliation(s)
- Aymen Al-Rawi
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK; Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Edward Kaye
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | | | - Jane A Endicott
- Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK; Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Tony Ly
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK; Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK.
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16
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Regulation of cell size and Wee1 kinase by elevated levels of the cell cycle regulatory protein kinase Cdr2. J Biol Chem 2022; 299:102831. [PMID: 36574843 PMCID: PMC9860436 DOI: 10.1016/j.jbc.2022.102831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/12/2022] [Accepted: 12/15/2022] [Indexed: 12/25/2022] Open
Abstract
Many cell cycle regulatory proteins catalyze cell cycle progression in a concentration-dependent manner. In the fission yeast Schizosaccharomyces pombe, the protein kinase Cdr2 promotes mitotic entry by organizing cortical oligomeric nodes that lead to inhibition of Wee1, which itself inhibits the cyclin-dependent kinase Cdk1. cdr2Δ cells lack nodes and divide at increased size due to overactive Wee1, but it has not been known how increased Cdr2 levels might impact Wee1 and cell size. It also has not been clear if and how Cdr2 might regulate Wee1 in the absence of the related kinase Cdr1/Nim1. Using a tetracycline-inducible expression system, we found that a 6× increase in Cdr2 expression caused hyperphosphorylation of Wee1 and reduction in cell size even in the absence of Cdr1/Nim1. This overexpressed Cdr2 formed clusters that sequestered Wee1 adjacent to the nuclear envelope. Cdr2 mutants that disrupt either kinase activity or clustering ability failed to sequester Wee1 and to reduce cell size. We propose that Cdr2 acts as a dosage-dependent regulator of cell size by sequestering its substrate Wee1 in cytoplasmic clusters, away from Cdk1 in the nucleus. This mechanism has implications for other clustered kinases, which may act similarly by sequestering substrates.
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17
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Sayyad WA, Pollard TD. The number of cytokinesis nodes in mitotic fission yeast scales with cell size. eLife 2022; 11:76249. [PMID: 36093997 PMCID: PMC9467510 DOI: 10.7554/elife.76249] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 08/18/2022] [Indexed: 11/22/2022] Open
Abstract
Cytokinesis nodes are assemblies of stoichiometric ratios of proteins associated with the plasma membrane, which serve as precursors for the contractile ring during cytokinesis by fission yeast. The total number of nodes is uncertain, because of the limitations of the methods used previously. Here, we used the ~140 nm resolution of Airyscan super-resolution microscopy to measure the fluorescence intensity of small, single cytokinesis nodes marked with Blt1-mEGFP in live fission yeast cells early in mitosis. The ratio of the total Blt1-mEGFP fluorescence in the broad band of cytokinesis nodes to the average fluorescence of a single node gives about 190 single cytokinesis nodes in wild-type fission yeast cells early in mitosis. Most, but not all of these nodes condense into a contractile ring. The number of cytokinesis nodes scales with cell size in four strains tested, although large diameter rga4Δ mutant cells form somewhat fewer cytokinesis nodes than expected from the overall trend. The Pom1 kinase restricts cytokinesis nodes from the ends of cells, but the surface density of Pom1 on the plasma membrane around the equators of cells is similar with a wide range of node numbers, so Pom1 does not control cytokinesis node number. However, when the concentrations of either kinase Pom1 or kinase Cdr2 were varied with the nmt1 promoter, the numbers of cytokinesis nodes increased above a baseline of about ~190 with the total cellular concentration of either kinase.
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Affiliation(s)
- Wasim A Sayyad
- Department of Molecular Cellular and Developmental Biology,Yale University, New Haven, United States
| | - Thomas D Pollard
- Department of Molecular Cellular and Developmental Biology,Yale University, New Haven, United States.,Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, United States.,Department of Cell Biology,Yale University, New Haven, United States
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18
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Curran S, Dey G, Rees P, Nurse P. A quantitative and spatial analysis of cell cycle regulators during the fission yeast cycle. Proc Natl Acad Sci U S A 2022; 119:e2206172119. [PMID: 36037351 PMCID: PMC9457408 DOI: 10.1073/pnas.2206172119] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 07/27/2022] [Indexed: 11/23/2022] Open
Abstract
We have carried out a systems-level analysis of the spatial and temporal dynamics of cell cycle regulators in the fission yeast Schizosaccharomyces pombe. In a comprehensive single-cell analysis, we have precisely quantified the levels of 38 proteins previously identified as regulators of the G2 to mitosis transition and of 7 proteins acting at the G1- to S-phase transition. Only 2 of the 38 mitotic regulators exhibit changes in concentration at the whole-cell level: the mitotic B-type cyclin Cdc13, which accumulates continually throughout the cell cycle, and the regulatory phosphatase Cdc25, which exhibits a complex cell cycle pattern. Both proteins show similar patterns of change within the nucleus as in the whole cell but at higher concentrations. In addition, the concentrations of the major fission yeast cyclin-dependent kinase (CDK) Cdc2, the CDK regulator Suc1, and the inhibitory kinase Wee1 also increase in the nucleus, peaking at mitotic onset, but are constant in the whole cell. The significant increase in concentration with size for Cdc13 supports the view that mitotic B-type cyclin accumulation could act as a cell size sensor. We propose a two-step process for the control of mitosis. First, Cdc13 accumulates in a size-dependent manner, which drives increasing CDK activity. Second, from mid-G2, the increasing nuclear accumulation of Cdc25 and the counteracting Wee1 introduce a bistability switch that results in a rapid rise of CDK activity at the end of G2 and thus, brings about an orderly progression into mitosis.
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Affiliation(s)
- Scott Curran
- Cell Cycle Laboratory, The Francis Crick Institute, London, NW1 1AT, United Kingdom
| | - Gautam Dey
- Medical Research Council Laboratory for Molecular Cell Biology, London, WC1E 6BT, United Kingdom
| | - Paul Rees
- College of Engineering, Swansea University, Swansea, SA1 8EN, United Kingdom
- Imaging Platform Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, MA 02142
| | - Paul Nurse
- Cell Cycle Laboratory, The Francis Crick Institute, London, NW1 1AT, United Kingdom
- Laboratory of Yeast Genetics and Cell Biology, Rockefeller University, New York, NY 10065
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19
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Kuenzel NA, Alcázar-Román AR, Saiardi A, Bartsch SM, Daunaraviciute S, Fiedler D, Fleig U. Inositol Pyrophosphate-Controlled Kinetochore Architecture and Mitotic Entry in S. pombe. J Fungi (Basel) 2022; 8:933. [PMID: 36135658 PMCID: PMC9506091 DOI: 10.3390/jof8090933] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 08/26/2022] [Accepted: 08/30/2022] [Indexed: 11/16/2022] Open
Abstract
Inositol pyrophosphates (IPPs) comprise a specific class of signaling molecules that regulate central biological processes in eukaryotes. The conserved Vip1/PPIP5K family controls intracellular IP8 levels, the highest phosphorylated form of IPPs present in yeasts, as it has both inositol kinase and pyrophosphatase activities. Previous studies have shown that the fission yeast S. pombe Vip1/PPIP5K family member Asp1 impacts chromosome transmission fidelity via the modulation of spindle function. We now demonstrate that an IP8 analogue is targeted by endogenous Asp1 and that cellular IP8 is subject to cell cycle control. Mitotic entry requires Asp1 kinase function and IP8 levels are increased at the G2/M transition. In addition, the kinetochore, the conductor of chromosome segregation that is assembled on chromosomes is modulated by IP8. Members of the yeast CCAN kinetochore-subcomplex such as Mal2/CENP-O localize to the kinetochore depending on the intracellular IP8-level: higher than wild-type IP8 levels reduce Mal2 kinetochore targeting, while a reduction in IP8 has the opposite effect. As our perturbations of the inositol polyphosphate and IPP pathways demonstrate that kinetochore architecture depends solely on IP8 and not on other IPPs, we conclude that chromosome transmission fidelity is controlled by IP8 via an interplay between entry into mitosis, kinetochore architecture, and spindle dynamics.
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Affiliation(s)
- Natascha Andrea Kuenzel
- Eukaryotic Microbiology, Institute of Functional Microbial Genomics, Heinrich-Heine-University, Universitätsstrasse 1, 40225 Düsseldorf, Germany
| | - Abel R. Alcázar-Román
- Eukaryotic Microbiology, Institute of Functional Microbial Genomics, Heinrich-Heine-University, Universitätsstrasse 1, 40225 Düsseldorf, Germany
| | - Adolfo Saiardi
- Medical Research Council Laboratory for Molecular Cell Biology, University College London, Gower St., London WC1E 6BT, UK
| | - Simon M. Bartsch
- Leibniz Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Straße 10, 13125 Berlin, Germany
- Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany
| | - Sarune Daunaraviciute
- Eukaryotic Microbiology, Institute of Functional Microbial Genomics, Heinrich-Heine-University, Universitätsstrasse 1, 40225 Düsseldorf, Germany
| | - Dorothea Fiedler
- Leibniz Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Straße 10, 13125 Berlin, Germany
- Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany
| | - Ursula Fleig
- Eukaryotic Microbiology, Institute of Functional Microbial Genomics, Heinrich-Heine-University, Universitätsstrasse 1, 40225 Düsseldorf, Germany
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20
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The Mis6 inner kinetochore subcomplex maintains CENP-A nucleosomes against centromeric non-coding transcription during mitosis. Commun Biol 2022; 5:818. [PMID: 35970865 PMCID: PMC9378642 DOI: 10.1038/s42003-022-03786-y] [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: 10/28/2021] [Accepted: 08/02/2022] [Indexed: 11/29/2022] Open
Abstract
Centromeres are established by nucleosomes containing the histone H3 variant CENP-A. CENP-A is recruited to centromeres by the Mis18–HJURP machinery. During mitosis, CENP-A recruitment ceases, implying the necessity of CENP-A maintenance at centromeres, although the exact underlying mechanism remains elusive. Herein, we show that the inner kinetochore protein Mis6 (CENP-I) and Mis15 (CENP-N) retain CENP-A during mitosis in fission yeast. Eliminating Mis6 or Mis15 during mitosis caused immediate loss of pre-existing CENP-A at centromeres. CENP-A loss occurred due to the transcriptional upregulation of non-coding RNAs at the central core region of centromeres, as confirmed by the observation RNA polymerase II inhibition preventing CENP-A loss from centromeres in the mis6 mutant. Thus, we concluded that the inner kinetochore complex containing Mis6–Mis15 blocks the indiscriminate transcription of non-coding RNAs at the core centromere, thereby retaining the epigenetic inheritance of CENP-A during mitosis. The kinetochore protein Mis6 (CENP-I) plays an important role in CENP-A maintenance during mitosis in fission yeast and blocks the indiscriminate transcription of non-coding RNAs at the core centromere to retain CENP-A during mitosis.
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21
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Cedeno-Rosario L, Honda D, Sunderland AM, Lewandowski MD, Taylor WR, Chadee DN. Phosphorylation of mixed lineage kinase MLK3 by cyclin-dependent kinases CDK1 and CDK2 controls ovarian cancer cell division. J Biol Chem 2022; 298:102263. [PMID: 35843311 PMCID: PMC9399292 DOI: 10.1016/j.jbc.2022.102263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 07/01/2022] [Accepted: 07/05/2022] [Indexed: 11/03/2022] Open
Abstract
Mixed lineage kinase 3 (MLK3) is a serine/threonine mitogen-activated protein kinase kinase kinase that promotes the activation of multiple mitogen-activated protein kinase pathways and is required for invasion and proliferation of ovarian cancer cells. Inhibition of MLK activity causes G2/M arrest in HeLa cells; however, the regulation of MLK3 during ovarian cancer cell cycle progression is not known. Here, we found that MLK3 is phosphorylated in mitosis and that inhibition of cyclin-dependent kinase 1 (CDK1) prevented MLK3 phosphorylation. In addition, we observed that c-Jun N-terminal kinase, a downstream target of MLK3 and a direct target of MKK4 (SEK1), was activated in G2 phase when CDK2 activity is increased and then inactivated at the beginning of mitosis concurrent with the increase in CDK1 and MLK3 phosphorylation. Using in vitro kinase assays and phosphomutants, we determined that CDK1 phosphorylates MLK3 on Ser548 and decreases MLK3 activity during mitosis, whereas CDK2 phosphorylates MLK3 on Ser770 and increases MLK3 activity during G1/S and G2 phases. We also found that MLK3 inhibition causes a reduction in cell proliferation and a cell cycle arrest in ovarian cancer cells, suggesting that MLK3 is required for ovarian cancer cell cycle progression. Taken together, our results suggest that phosphorylation of MLK3 by CDK1 and CDK2 is important for the regulation of MLK3 and c-Jun N-terminal kinase activities during G1/S, G2, and M phases in ovarian cancer cell division.
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Affiliation(s)
- Luis Cedeno-Rosario
- Department of Biological Sciences, College of Natural Sciences and Mathematics, The University of Toledo, Toledo, Ohio, USA
| | - David Honda
- Department of Biological Sciences, College of Natural Sciences and Mathematics, The University of Toledo, Toledo, Ohio, USA
| | - Autumn M Sunderland
- Department of Biological Sciences, College of Natural Sciences and Mathematics, The University of Toledo, Toledo, Ohio, USA
| | - Mark D Lewandowski
- Department of Biological Sciences, College of Natural Sciences and Mathematics, The University of Toledo, Toledo, Ohio, USA
| | - William R Taylor
- Department of Biological Sciences, College of Natural Sciences and Mathematics, The University of Toledo, Toledo, Ohio, USA
| | - Deborah N Chadee
- Department of Biological Sciences, College of Natural Sciences and Mathematics, The University of Toledo, Toledo, Ohio, USA.
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22
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Abstract
Upon DNA damage, complex transduction cascades are unleashed to locate, recognise and repair affected lesions. The process triggers a pause in the cell cycle until the damage is resolved. Even under physiologic conditions, this deliberate interruption of cell division is essential to ensure orderly DNA replication and chromosomal segregation. WEE1 is an established regulatory protein in this vast fidelity-monitoring machinery. Its involvement in the DNA damage response and cell cycle has been a subject of study for decades. Emerging studies have also implicated WEE1 directly and indirectly in other cellular functions, including chromatin remodelling and immune response. The expanding role of WEE1 in pathophysiology is matched by the keen surge of interest in developing WEE1-targeted therapeutic agents. This review summarises WEE1 involvement in the cell cycle checkpoints, epigenetic modification and immune signalling, as well as the current state of WEE1 inhibitors in cancer therapeutics.
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23
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From the Belousov-Zhabotinsky reaction to biochemical clocks, traveling waves and cell cycle regulation. Biochem J 2022; 479:185-206. [PMID: 35098993 DOI: 10.1042/bcj20210370] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 12/10/2021] [Accepted: 12/13/2021] [Indexed: 01/23/2023]
Abstract
In the last 20 years, a growing army of systems biologists has employed quantitative experimental methods and theoretical tools of data analysis and mathematical modeling to unravel the molecular details of biological control systems with novel studies of biochemical clocks, cellular decision-making, and signaling networks in time and space. Few people know that one of the roots of this new paradigm in cell biology can be traced to a serendipitous discovery by an obscure Russian biochemist, Boris Belousov, who was studying the oxidation of citric acid. The story is told here from an historical perspective, tracing its meandering path through glycolytic oscillations, cAMP signaling, and frog egg development. The connections among these diverse themes are drawn out by simple mathematical models (nonlinear differential equations) that share common structures and properties.
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24
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Liu K, Liu Q, Sun Y, Fan J, Zhang Y, Sakamoto N, Kuno T, Fang Y. Phosphoinositide-Dependent Protein Kinases Regulate Cell Cycle Progression Through the SAD Kinase Cdr2 in Fission Yeast. Front Microbiol 2022; 12:807148. [PMID: 35082773 PMCID: PMC8784684 DOI: 10.3389/fmicb.2021.807148] [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: 11/01/2021] [Accepted: 12/15/2021] [Indexed: 11/23/2022] Open
Abstract
Aberration in the control of cell cycle contributes to the development and progression of many diseases including cancers. Ksg1 is a Schizosaccharomyces pombe fission yeast homolog of mammalian phosphoinositide-dependent protein kinase 1 (PDK1) which is regarded as a signaling hub for human tumorigenesis. A previous study reported that Ksg1 plays an important role in cell cycle progression, however, the underlying mechanism remains elusive. Our genomic library screen for novel elements involved in Ksg1 function identified two serine/threonine kinases, namely SAD family kinase Cdr2 and another PDK1 homolog Ppk21, as multicopy suppressors of the thermosensitive phenotype of ksg1-208 mutant. We found that overexpression of Ppk21 or Cdr2 recovered the defective cell cycle transition of ksg1-208 mutant. In addition, ksg1-208 Δppk21 cells showed more marked defects in cell cycle transition than each single mutant. Moreover, overexpression of Ppk21 failed to recover the thermosensitive phenotype of the ksg1-208 mutant when Cdr2 was lacking. Notably, the ksg1-208 mutation resulted in abnormal subcellular localization and decreased abundance of Cdr2, and Ppk21 deletion exacerbated the decreased abundance of Cdr2 in the ksg1-208 mutant. Intriguingly, expression of a mitotic inducer Cdc25 was significantly decreased in ksg1-208, Δppk21, or Δcdr2 cells, and overexpression of Ppk21 or Cdr2 partially recovered the decreased protein level of Cdc25 in the ksg1-208 mutant. Altogether, our findings indicated that Cdr2 is a novel downstream effector of PDK1 homologs Ksg1 and Ppk21, both of which cooperatively participate in regulating cell cycle progression, and Cdc25 is involved in this process in fission yeast.
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Affiliation(s)
- Kun Liu
- Department of Microbial and Biochemical Pharmacy, School of Pharmacy, China Medical University, Shenyang, China
| | - Qiannan Liu
- Department of Microbial and Biochemical Pharmacy, School of Pharmacy, China Medical University, Shenyang, China
| | - Yanli Sun
- Department of Microbial and Biochemical Pharmacy, School of Pharmacy, China Medical University, Shenyang, China
| | - Jinwei Fan
- Department of Microbial and Biochemical Pharmacy, School of Pharmacy, China Medical University, Shenyang, China
| | - Yu Zhang
- Department of Microbial and Biochemical Pharmacy, School of Pharmacy, China Medical University, Shenyang, China
| | - Norihiro Sakamoto
- Division of Food and Drug Evaluation Science, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Takayoshi Kuno
- Department of Microbial and Biochemical Pharmacy, School of Pharmacy, China Medical University, Shenyang, China
- Division of Food and Drug Evaluation Science, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Yue Fang
- Department of Microbial and Biochemical Pharmacy, School of Pharmacy, China Medical University, Shenyang, China
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25
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Sazonova EV, Petrichuk SV, Kopeina GS, Zhivotovsky B. A link between mitotic defects and mitotic catastrophe: detection and cell fate. Biol Direct 2021; 16:25. [PMID: 34886882 PMCID: PMC8656038 DOI: 10.1186/s13062-021-00313-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Accepted: 11/14/2021] [Indexed: 02/08/2023] Open
Abstract
Although the phenomenon of mitotic catastrophe was first described more than 80 years ago, only recently has this term been used to explain a mechanism of cell death linked to delayed mitosis. Several mechanisms have been suggested for mitotic catastrophe development and cell fate. Depending on molecular perturbations, mitotic catastrophe can end in three types of cell death, namely apoptosis, necrosis, or autophagy. Moreover, mitotic catastrophe can be associated with different types of cell aging, the development of which negatively affects tumor elimination and, consequently, reduces the therapeutic effect. The effective triggering of mitotic catastrophe in clinical practice requires induction of DNA damage as well as inhibition of the molecular pathways that regulate cell cycle arrest and DNA repair. Here we discuss various methods to detect mitotic catastrophe, the mechanisms of its development, and the attempts to use this phenomenon in cancer treatment.
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Affiliation(s)
- Elena V Sazonova
- Faculty of Medicine, MV Lomonosov Moscow State University, Moscow, Russia, 119991
| | - Svetlana V Petrichuk
- Federal State Autonomous Institution "National Medical Research Center for Children's Health" of the Ministry of Health of the Russian Federation, Moscow, Russia, 119296
| | - Gelina S Kopeina
- Faculty of Medicine, MV Lomonosov Moscow State University, Moscow, Russia, 119991.
| | - Boris Zhivotovsky
- Faculty of Medicine, MV Lomonosov Moscow State University, Moscow, Russia, 119991.
- Division of Toxicology, Institute of Environmental Medicine, Karolinska Institute, Box 210, 17177, Stockholm, Sweden.
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26
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Jung Y, Kraikivski P, Shafiekhani S, Terhune SS, Dash RK. Crosstalk between Plk1, p53, cell cycle, and G2/M DNA damage checkpoint regulation in cancer: computational modeling and analysis. NPJ Syst Biol Appl 2021; 7:46. [PMID: 34887439 PMCID: PMC8660825 DOI: 10.1038/s41540-021-00203-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 11/03/2021] [Indexed: 12/21/2022] Open
Abstract
Different cancer cell lines can have varying responses to the same perturbations or stressful conditions. Cancer cells that have DNA damage checkpoint-related mutations are often more sensitive to gene perturbations including altered Plk1 and p53 activities than cancer cells without these mutations. The perturbations often induce a cell cycle arrest in the former cancer, whereas they only delay the cell cycle progression in the latter cancer. To study crosstalk between Plk1, p53, and G2/M DNA damage checkpoint leading to differential cell cycle regulations, we developed a computational model by extending our recently developed model of mitotic cell cycle and including these key interactions. We have used the model to analyze the cancer cell cycle progression under various gene perturbations including Plk1-depletion conditions. We also analyzed mutations and perturbations in approximately 1800 different cell lines available in the Cancer Dependency Map and grouped lines by genes that are represented in our model. Our model successfully explained phenotypes of various cancer cell lines under different gene perturbations. Several sensitivity analysis approaches were used to identify the range of key parameter values that lead to the cell cycle arrest in cancer cells. Our resulting model can be used to predict the effect of potential treatments targeting key mitotic and DNA damage checkpoint regulators on cell cycle progression of different types of cancer cells.
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Affiliation(s)
- Yongwoon Jung
- grid.30760.320000 0001 2111 8460Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, WI 53226 USA
| | - Pavel Kraikivski
- Academy of Integrated Science, Division of Systems Biology, Virginia Tech, Blacksburg, VA, 24061, USA.
| | - Sajad Shafiekhani
- grid.411705.60000 0001 0166 0922Department of Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Scott S. Terhune
- grid.30760.320000 0001 2111 8460Departments of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI 53226 USA ,grid.30760.320000 0001 2111 8460Center of Systems and Molecular Medicine, Medical College of Wisconsin, Milwaukee, WI 53226 USA
| | - Ranjan K. Dash
- grid.30760.320000 0001 2111 8460Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, WI 53226 USA ,grid.30760.320000 0001 2111 8460Center of Systems and Molecular Medicine, Medical College of Wisconsin, Milwaukee, WI 53226 USA ,grid.30760.320000 0001 2111 8460Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226 USA
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27
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Roy S, Rangasamy L, Nouar A, Koenig C, Pierroz V, Kaeppeli S, Ferrari S, Patra M, Gasser G. Synthesis and Biological Evaluation of Metallocene-Tethered Peptidyl Inhibitors of CDC25. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Saonli Roy
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Loganathan Rangasamy
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Assia Nouar
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Christiane Koenig
- Institute of Molecular Cancer Research, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Vanessa Pierroz
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
- Institute of Molecular Cancer Research, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Simon Kaeppeli
- Institute of Molecular Cancer Research, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Stefano Ferrari
- Institute of Molecular Cancer Research, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Malay Patra
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Laboratory of Medicinal Chemistry and Cell Biology, Homi Bhabha Road, Navy Nagar, 400005 Mumbai, India
| | - Gilles Gasser
- Chimie ParisTech, PSL University, CNRS, Institute of Chemistry for Life and Health Sciences, Laboratory for Inorganic Chemical Biology, F-75005 Paris, France
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28
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Patterson JO, Basu S, Rees P, Nurse P. CDK control pathways integrate cell size and ploidy information to control cell division. eLife 2021; 10:64592. [PMID: 34114564 PMCID: PMC8248981 DOI: 10.7554/elife.64592] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 05/24/2021] [Indexed: 12/27/2022] Open
Abstract
Maintenance of cell size homeostasis is a property that is conserved throughout eukaryotes. Cell size homeostasis is brought about by the co-ordination of cell division with cell growth and requires restriction of smaller cells from undergoing mitosis and cell division, whilst allowing larger cells to do so. Cyclin-CDK is the fundamental driver of mitosis and therefore ultimately ensures size homeostasis. Here we dissect determinants of CDK activity in vivo to investigate how cell size information is processed by the cell cycle network in fission yeast. We develop a high-throughput single-cell assay system of CDK activity in vivo and show that inhibitory tyrosine phosphorylation of CDK encodes cell size information, with the phosphatase PP2A aiding to set a size threshold for division. CDK inhibitory phosphorylation works synergistically with PP2A to prevent mitosis in smaller cells. Finally, we find that diploid cells of equivalent size to haploid cells exhibit lower CDK activity in response to equal cyclin-CDK enzyme concentrations, suggesting that CDK activity is reduced by increased DNA levels. Therefore, scaling of cyclin-CDK levels with cell size, CDK inhibitory phosphorylation, PP2A, and DNA-dependent inhibition of CDK activity, all inform the cell cycle network of cell size, thus contributing to cell size homeostasis.
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Affiliation(s)
- James Oliver Patterson
- Cell Cycle Laboratory, The Francis Crick Institute, London, United Kingdom.,College of Engineering, Swansea University, Swansea, United Kingdom
| | - Souradeep Basu
- Cell Cycle Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Paul Rees
- College of Engineering, Swansea University, Swansea, United Kingdom.,Imaging Platform, Broad Institute of Harvard and MIT, Cambridge, United States
| | - Paul Nurse
- Cell Cycle Laboratory, The Francis Crick Institute, London, United Kingdom.,Laboratory of Yeast Genetics and Cell Biology, Rockefeller University, New York, United States
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29
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Vyas A, Freitas AV, Ralston ZA, Tang Z. Fission Yeast Schizosaccharomyces pombe: A Unicellular "Micromammal" Model Organism. Curr Protoc 2021; 1:e151. [PMID: 34101381 PMCID: PMC8193909 DOI: 10.1002/cpz1.151] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The fission yeast Schizosaccharomyces pombe is a rod-shaped unicellular eukaryote, well known for its contributions as a model organism for our understanding of regulation and conservation of the eukaryotic cell cycle. As a yeast divergent from the budding yeast Saccharomyces cerevisiae, S. pombe shares more common features with humans including gene structures, chromatin dynamics, and the prevalence of introns, as well as the control of gene expression through pre-mRNA splicing, epigenetic gene silencing, and RNAi pathways. With the advent of new methodologies for research, S. pombe has become an increasingly used model to investigate various molecular and cellular processes over the last 50 years. Also, S. pombe serves as an excellent system for undergraduate students to obtain hands-on research experience. Versatile experimental approaches are amenable using the fission yeast system due to its relative ease of maintenance, its inherent cellular properties, its power in classic and molecular genetics, and its feasibility in genomics and proteomics analyses. This article provides an overview of S. pombe's rise as a valuable model organism and presents examples to highlight the significance of S. pombe as a unicellular "micromammal" in investigating biological questions. We especially focus on the advantages of and the advancements in using fission yeast for studying biological processes that are characteristic of metazoans to decipher the underlining molecular mechanisms fundamental to all eukaryotes. © 2021 Wiley Periodicals LLC.
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Affiliation(s)
- Aditi Vyas
- W.M. Keck Science Department, The Claremont Colleges, Claremont, CA 91711, USA
| | - Anna V. Freitas
- W.M. Keck Science Department, The Claremont Colleges, Claremont, CA 91711, USA
| | - Zachary A. Ralston
- W.M. Keck Science Department, The Claremont Colleges, Claremont, CA 91711, USA
| | - Zhaohua Tang
- W.M. Keck Science Department, The Claremont Colleges, Claremont, CA 91711, USA
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30
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In Silico Identification of Small Molecules as New Cdc25 Inhibitors through the Correlation between Chemosensitivity and Protein Expression Pattern. Int J Mol Sci 2021; 22:ijms22073714. [PMID: 33918281 PMCID: PMC8038176 DOI: 10.3390/ijms22073714] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 03/29/2021] [Accepted: 03/31/2021] [Indexed: 01/11/2023] Open
Abstract
The cell division cycle 25 (Cdc25) protein family plays a crucial role in controlling cell proliferation, making it an excellent target for cancer therapy. In this work, a set of small molecules were identified as Cdc25 modulators by applying a mixed ligand-structure-based approach and taking advantage of the correlation between the chemosensitivity of selected structures and the protein expression pattern of the proposed target. In the first step of the in silico protocol, a set of molecules acting as Cdc25 inhibitors were identified through a new ligand-based protocol and the evaluation of a large database of molecular structures. Subsequently, induced-fit docking (IFD) studies allowed us to further reduce the number of compounds biologically screened. In vitro antiproliferative and enzymatic inhibition assays on the selected compounds led to the identification of new structurally heterogeneous inhibitors of Cdc25 proteins. Among them, J3955, the most active inhibitor, showed concentration-dependent antiproliferative activity against HepG2 cells, with GI50 in the low micromolar range. When J3955 was tested in cell-cycle perturbation experiments, it caused mitotic failure by G2/M-phase cell-cycle arrest. Finally, Western blotting analysis showed an increment of phosphorylated Cdk1 levels in cells exposed to J3955, indicating its specific influence in cellular pathways involving Cdc25 proteins.
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31
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Gerganova V, Bhatia P, Vincenzetti V, Martin SG. Direct and indirect regulation of Pom1 cell size pathway by the protein phosphatase 2C Ptc1. Mol Biol Cell 2021; 32:703-711. [PMID: 33625871 PMCID: PMC8108516 DOI: 10.1091/mbc.e20-08-0508] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The fission yeast cells Schizosaccharomyces pombe divide at constant cell size regulated by environmental stimuli. An important pathway of cell size control involves the membrane-associated DYRK-family kinase Pom1, which forms decreasing concentration gradients from cell poles and inhibits mitotic inducers at midcell. Here, we identify the phosphatase 2C Ptc1 as negative regulator of Pom1. Ptc1 localizes to cell poles in a manner dependent on polarity and cell-wall integrity factors. We show that Ptc1 directly binds Pom1 and can dephosphorylate it in vitro but modulates Pom1 localization indirectly upon growth in low-glucose conditions by influencing microtubule stability. Thus, Ptc1 phosphatase plays both direct and indirect roles in the Pom1 cell size control pathway.
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Affiliation(s)
- Veneta Gerganova
- Department of Fundamental Microbiology, University of Lausanne, 1015 Lausanne, Switzerland
| | - Payal Bhatia
- Department of Fundamental Microbiology, University of Lausanne, 1015 Lausanne, Switzerland
| | - Vincent Vincenzetti
- Department of Fundamental Microbiology, University of Lausanne, 1015 Lausanne, Switzerland
| | - Sophie G Martin
- Department of Fundamental Microbiology, University of Lausanne, 1015 Lausanne, Switzerland
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32
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Scotchman E, Kume K, Navarro FJ, Nurse P. Identification of mutants with increased variation in cell size at onset of mitosis in fission yeast. J Cell Sci 2021; 134:jcs251769. [PMID: 33419777 PMCID: PMC7888708 DOI: 10.1242/jcs.251769] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 12/10/2020] [Indexed: 12/19/2022] Open
Abstract
Fission yeast cells divide at a similar cell length with little variation about the mean. This is thought to be the result of a control mechanism that senses size and corrects for any deviations by advancing or delaying onset of mitosis. Gene deletions that advance cells into mitosis at a smaller size or delay cells entering mitosis have led to the identification of genes potentially involved in this mechanism. However, the molecular basis of this control is still not understood. In this work, we have screened for genes that when deleted increase the variability in size of dividing cells. The strongest candidate identified in this screen was mga2 The mga2 deletion strain shows a greater variation in cell length at division, with a coefficient of variation (CV) of 15-24%, while the wild-type strain has a CV of 5-8%. Furthermore, unlike wild-type cells, the mga2 deletion cells are unable to correct cell size deviations within one cell cycle. We show that the mga2 gene genetically interacts with nem1 and influences the nuclear membrane and the nuclear-cytoplasmic transport of CDK regulators.
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Affiliation(s)
| | - Kazunori Kume
- Cell Cycle Laboratory, The Francis Crick Institute, London NW1 1AT, UK
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8530, Japan
- Hiroshima Research Center for Healthy Aging (HiHA), Hiroshima University,Higashi-Hiroshima, Hiroshima 739-8530, Japan
| | | | - Paul Nurse
- Cell Cycle Laboratory, The Francis Crick Institute, London NW1 1AT, UK
- Laboratory of Yeast Genetics and Cell Biology, Rockefeller University, New York, NY 10065, USA
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33
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Novák B, Tyson JJ. Computational modeling of chromosome re-replication in mutant strains of fission yeast. Mol Biol Cell 2021; 32:830-841. [PMID: 33534609 PMCID: PMC8108527 DOI: 10.1091/mbc.e20-09-0610] [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] [Indexed: 11/28/2022] Open
Abstract
Typically cells replicate their genome only once per division cycle, but under some circumstances, both natural and unnatural, cells synthesize an overabundance of DNA, either in a disorganized manner (“overreplication”) or by a systematic doubling of chromosome number (“endoreplication”). These variations on the theme of DNA replication and division have been studied in strains of fission yeast, Schizosaccharomyces pombe, carrying mutations that interfere with the function of mitotic cyclin-dependent kinase (Cdk1:Cdc13) without impeding the roles of DNA-replication loading factor (Cdc18) and S-phase cyclin-dependent kinase (Cdk1:Cig2). Some of these mutations support endoreplication, and some overreplication. In this paper, we propose a dynamical model of the interactions among the proteins governing DNA replication and cell division in fission yeast. By computational simulations of the mathematical model, we account for the observed phenotypes of these re-replicating mutants, and by theoretical analysis of the dynamical system, we provide insight into the molecular distinctions between overreplicating and endoreplicating cells. In the case of induced overproduction of regulatory proteins, our model predicts that cells first switch from normal mitotic cell cycles to growth-controlled endoreplication, and ultimately to disorganized overreplication, parallel to the slow increase of protein to very high levels.
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Affiliation(s)
- Béla Novák
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
| | - John J Tyson
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
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34
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Galli M, Diani L, Quadri R, Nespoli A, Galati E, Panigada D, Plevani P, Muzi-Falconi M. Haspin Modulates the G2/M Transition Delay in Response to Polarization Failures in Budding Yeast. Front Cell Dev Biol 2021; 8:625717. [PMID: 33585466 PMCID: PMC7876276 DOI: 10.3389/fcell.2020.625717] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 12/28/2020] [Indexed: 01/25/2023] Open
Abstract
Symmetry breaking by cellular polarization is an exquisite requirement for the cell-cycle of Saccharomyces cerevisiae cells, as it allows bud emergence and growth. This process is based on the formation of polarity clusters at the incipient bud site, first, and the bud tip later in the cell-cycle, that overall promote bud emission and growth. Given the extreme relevance of this process, a surveillance mechanism, known as the morphogenesis checkpoint, has evolved to coordinate the formation of the bud and cell cycle progression, delaying mitosis in the presence of morphogenetic problems. The atypical protein kinase haspin is responsible for histone H3-T3 phosphorylation and, in yeast, for resolution of polarity clusters in mitosis. Here, we report a novel role for haspin in the regulation of the morphogenesis checkpoint in response to polarity insults. Particularly, we show that cells lacking the haspin ortholog Alk1 fail to achieve sustained checkpoint activation and enter mitosis even in the absence of a bud. In alk1Δ cells, we report a reduced phosphorylation of Cdc28-Y19, which stems from a premature activation of the Mih1 phosphatase. Overall, the data presented in this work define yeast haspin as a novel regulator of the morphogenesis checkpoint in Saccharomyces cerevisiae, where it monitors polarity establishment and it couples bud emergence to the G2/M cell cycle transition.
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Affiliation(s)
- Martina Galli
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milano, Italy
| | - Laura Diani
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milano, Italy
| | - Roberto Quadri
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milano, Italy
| | - Alessandro Nespoli
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milano, Italy
| | - Elena Galati
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milano, Italy
| | - Davide Panigada
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milano, Italy
| | - Paolo Plevani
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milano, Italy
| | - Marco Muzi-Falconi
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milano, Italy
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35
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Bravo-San Pedro JM, Kepp O, Sauvat A, Rello-Varona S, Kroemer G, Senovilla L. Clonogenic Assays to Detect Cell Fate in Mitotic Catastrophe. Methods Mol Biol 2021; 2267:227-239. [PMID: 33786796 DOI: 10.1007/978-1-0716-1217-0_16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Mitotic catastrophe (MC) is a cell death modality induced by DNA damage that involves the activation of cell cycle checkpoints such as the "DNA structure checkpoint" and "spindle assembly checkpoint" (SAC) leading to aberrant mitosis. Depending on the signal, MC can drive the cell to death or to senescence. The suppression of MC favors aneuploidy. Several cancer therapies, included microtubular poisons and radiations, trigger MC. The clonogenic assay has been used to study the capacity of single cells to proliferate and to generate macroscopic colonies and to evaluate the efficacy of anticancer drugs. Nevertheless, this method cannot analyze MC events. Here, we report an improved technique based on the use of human colon cancer HCT116 stable expressing histone H2B-GFP and DsRed-centrin proteins, allowing to determine the capacity of cells to proliferate, and to determine changes in the nucleus and centrosomes.
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Affiliation(s)
- José Manuel Bravo-San Pedro
- Centre de Recherche des Cordeliers, Sorbonne Université, Inserm, Université de Paris, Equipe 11 Labellisée par la Ligue Contre le Cancer, Paris, France.,Metabolomics and Cell Biology Platforms, Gustave Roussy Comprehensive Cancer Institute, Villejuif, France.,Departamento de Fisiología, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain
| | - Oliver Kepp
- Centre de Recherche des Cordeliers, Sorbonne Université, Inserm, Université de Paris, Equipe 11 Labellisée par la Ligue Contre le Cancer, Paris, France.,Metabolomics and Cell Biology Platforms, Gustave Roussy Comprehensive Cancer Institute, Villejuif, France
| | - Allan Sauvat
- Centre de Recherche des Cordeliers, Sorbonne Université, Inserm, Université de Paris, Equipe 11 Labellisée par la Ligue Contre le Cancer, Paris, France.,Metabolomics and Cell Biology Platforms, Gustave Roussy Comprehensive Cancer Institute, Villejuif, France
| | - Santiago Rello-Varona
- Centre de Recherche des Cordeliers, Sorbonne Université, Inserm, Université de Paris, Equipe 11 Labellisée par la Ligue Contre le Cancer, Paris, France.,Metabolomics and Cell Biology Platforms, Gustave Roussy Comprehensive Cancer Institute, Villejuif, France.,Cell Biology Department, School of Biological Sciences, Universidad Complutense de Madrid-UCM, Madrid, Spain.,Hospital La Paz Institute for Health Research-IdiPAZ, Madrid, Spain
| | - Guido Kroemer
- Centre de Recherche des Cordeliers, Sorbonne Université, Inserm, Université de Paris, Equipe 11 Labellisée par la Ligue Contre le Cancer, Paris, France. .,Metabolomics and Cell Biology Platforms, Gustave Roussy Comprehensive Cancer Institute, Villejuif, France. .,Pôle de Biologie, Hopitâl Européen George Pompidou, AP-HP, Paris, France. .,Center of Systems Medicine, Chinese Academy of Medical Science, Suzhou, China. .,Department of Women's and Children's Health, Karolinska University Hospital, Stockholm, Sweden.
| | - Laura Senovilla
- Centre de Recherche des Cordeliers, Sorbonne Université, Inserm, Université de Paris, Equipe 11 Labellisée par la Ligue Contre le Cancer, Paris, France. .,Metabolomics and Cell Biology Platforms, Gustave Roussy Comprehensive Cancer Institute, Villejuif, France.
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36
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Nurse P. Fission yeast cell cycle mutants and the logic of eukaryotic cell cycle control. Mol Biol Cell 2020; 31:2871-2873. [PMID: 33320707 PMCID: PMC7927194 DOI: 10.1091/mbc.e20-10-0623] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Cell cycle mutants in the budding and fission yeasts have played critical roles in working out how the eukaryotic cell cycle operates and is controlled. The starting point was Lee Hartwell’s 1970s landmark papers describing the first cell division cycle (CDC) mutants in budding yeast. These mutants were blocked at different cell cycle stages and so were unable to complete the cell cycle, thus defining genes necessary for successful cell division. Inspired by Hartwell’s work, I isolated CDC mutants in the very distantly related fission yeast. This started a program of searches for mutants in fission yeast that revealed a range of phenotypes informative about eukaryotic cell cycle control. These included mutants defining genes that were rate-limiting for the onset of mitosis and of the S-phase, that were responsible for there being only one S-phase in each cell cycle, and that ensured that mitosis only took place when S-phase was properly completed. This is a brief account of the discovery of these mutants and how they led to the identification of cyclin-dependent kinases as core to these cell cycle controls.
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Affiliation(s)
- Paul Nurse
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
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37
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Taheraly S, Ershov D, Dmitrieff S, Minc N. An image analysis method to survey the dynamics of polar protein abundance in the regulation of tip growth. J Cell Sci 2020; 133:133/22/jcs252064. [PMID: 33257499 DOI: 10.1242/jcs.252064] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 10/14/2020] [Indexed: 11/20/2022] Open
Abstract
Tip growth is critical for the lifestyle of many walled cells. In yeast and fungi, this process is typically associated with the polarized deposition of conserved tip factors, including landmarks, Rho GTPases, cytoskeleton regulators, and membrane and cell wall remodelers. Because tip growth speeds may vary extensively between life cycles or species, we asked whether the local amount of specific polar elements could determine or limit tip growth speeds. Using the model fission yeast, we developed a quantitative image analysis pipeline to dynamically correlate single tip elongation speeds and polar protein abundance in large data sets. We found that polarity landmarks are typically diluted by growth. In contrast, tip growth speed is positively correlated with the local amount of factors related to actin, secretion or cell wall remodeling, but, surprisingly, exhibits long saturation plateaus above certain concentrations of those factors. Similar saturation observed for Spitzenkörper components in much faster growing fungal hyphae suggests that elements independent of canonical surface remodelers may limit single tip growth. This work provides standardized methods and resources to decipher the complex mechanisms that control cell growth.This article has an associated First Person interview with Sarah Taheraly, joint first author of the paper.
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Affiliation(s)
- Sarah Taheraly
- Université de Paris, CNRS, Institut Jacques Monod, 75013, Paris, France
| | - Dmitry Ershov
- Université de Paris, CNRS, Institut Jacques Monod, 75013, Paris, France
| | - Serge Dmitrieff
- Université de Paris, CNRS, Institut Jacques Monod, 75013, Paris, France
| | - Nicolas Minc
- Université de Paris, CNRS, Institut Jacques Monod, 75013, Paris, France
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38
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Kulkarni A, Lopez DH, Extavour CG. Shared Cell Biological Functions May Underlie Pleiotropy of Molecular Interactions in the Germ Lines and Nervous Systems of Animals. Front Ecol Evol 2020. [DOI: 10.3389/fevo.2020.00215] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
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39
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Du LL. Resurrection from lethal knockouts: Bypass of gene essentiality. Biochem Biophys Res Commun 2020; 528:405-412. [PMID: 32507598 DOI: 10.1016/j.bbrc.2020.05.207] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 05/27/2020] [Indexed: 01/03/2023]
Abstract
Understanding genotype-phenotype relationships is a central pursuit in biology. Gene knockout generates a complete loss-of-function genotype and is a commonly used approach for probing gene functions. The most severe phenotypic consequence of gene knockout is lethality. Genes with a lethal knockout phenotype are called essential genes. Based on genome-wide knockout analyses in yeasts, up to approximately a quarter of genes in a genome can be essential. Like other genotype-phenotype relationships, gene essentiality is subject to background effects and can vary due to gene-gene interactions. In particular, for some essential genes, lethality caused by knockout can be rescued by extragenic suppressors. Such "bypass of essentiality" (BOE) gene-gene interactions have been an understudied type of genetic suppression. A recent systematic analysis revealed that, remarkably, the essentiality of nearly 30% of essential genes in the fission yeast Schizosaccharomyces pombe can be bypassed by BOE interactions. Here, I review the history and recent progress on uncovering and understanding the bypass of gene essentiality.
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Affiliation(s)
- Li-Lin Du
- National Institute of Biological Sciences, Beijing, 102206, China; Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing, 100084, China.
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40
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CDK Regulation of Meiosis: Lessons from S. cerevisiae and S. pombe. Genes (Basel) 2020; 11:genes11070723. [PMID: 32610611 PMCID: PMC7397238 DOI: 10.3390/genes11070723] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 06/26/2020] [Accepted: 06/26/2020] [Indexed: 12/13/2022] Open
Abstract
Meiotic progression requires precise orchestration, such that one round of DNA replication is followed by two meiotic divisions. The order and timing of meiotic events is controlled through the modulation of the phosphorylation state of proteins. Key components of this phospho-regulatory system include cyclin-dependent kinase (CDK) and its cyclin regulatory subunits. Over the past two decades, studies in budding and fission yeast have greatly informed our understanding of the role of CDK in meiotic regulation. In this review, we provide an overview of how CDK controls meiotic events in both budding and fission yeast. We discuss mechanisms of CDK regulation through post-translational modifications and changes in the levels of cyclins. Finally, we highlight the similarities and differences in CDK regulation between the two yeast species. Since CDK and many meiotic regulators are highly conserved, the findings in budding and fission yeasts have revealed conserved mechanisms of meiotic regulation among eukaryotes.
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41
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Liao Y, Xiao H, Cheng M, Fan X. Bioinformatics Analysis Reveals Biomarkers With Cancer Stem Cell Characteristics in Lung Squamous Cell Carcinoma. Front Genet 2020; 11:427. [PMID: 32528520 PMCID: PMC7247832 DOI: 10.3389/fgene.2020.00427] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 04/06/2020] [Indexed: 12/18/2022] Open
Abstract
Background Tumor stem cells play important roles in the survival, proliferation, metastasis and recurrence of tumors. We aimed to identify new prognostic biomarkers for lung squamous cell carcinoma (LUSC) based on the cancer stem cell theory. Methods RNA-seq data and relevant clinical information were downloaded from The Cancer Genome Atlas (TCGA) database. Weighted gene coexpression network analysis (WGCNA) was applied to identify significant modules and hub genes, and prognostic signatures were constructed with the prognostic hub genes. Results LUSC patients in the TCGA database have higher mRNA expression-based stemness index (mRNAsi) in tumor tissue than in adjacent normal tissue. In addition, some clinical features and outcomes were highly correlated with the mRNAsi. WGCNA revealed that the pink and yellow modules were the most significant modules related to the mRNAsi; the top 10 hub genes in the pink module were enriched mostly in epidermal development, the secretory granule membrane, receptor regulator activity and the cytokine-cytokine receptor interaction. The protein–protein interaction (PPI) network revealed that the top 10 hub genes were significantly correlated with each other at the transcriptional level. In addition, the top 10 hub genes were all highly expressed in LUSC, and some were differentially expressed in different TNM stages. Regarding the survival analysis, the nomogram of a prognostic signature with three hub genes showed high predictive value. Conclusion mRNAsi-related hub genes could be a potential biomarker of LUSC.
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Affiliation(s)
- Yi Liao
- Department of Respiratory and Critical Care Medicine II, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Hua Xiao
- Department of Respiratory and Critical Care Medicine II, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Mengqing Cheng
- Department of Respiratory and Critical Care Medicine II, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Xianming Fan
- Department of Respiratory and Critical Care Medicine II, The Affiliated Hospital of Southwest Medical University, Luzhou, China
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42
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Juric V, Murphy B. Cyclin-dependent kinase inhibitors in brain cancer: current state and future directions. CANCER DRUG RESISTANCE (ALHAMBRA, CALIF.) 2020; 3:48-62. [PMID: 35582046 PMCID: PMC9094053 DOI: 10.20517/cdr.2019.105] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 12/11/2019] [Accepted: 12/20/2019] [Indexed: 12/12/2022]
Abstract
Cyclin-dependent kinases (CDKs) are important regulatory enzymes in the normal physiological processes that drive cell-cycle transitions and regulate transcription. Virtually all cancers harbour genomic alterations that lead to the constitutive activation of CDKs, resulting in the proliferation of cancer cells. CDK inhibitors (CKIs) are currently in clinical use for the treatment of breast cancer, combined with endocrine therapy. In this review, we describe the potential of CKIs for the treatment of cancer with specific focus on glioblastoma (GBM), the most common and aggressive primary brain tumour in adults. Despite intense effort to combat GBM with surgery, radiation and temozolomide chemotherapy, the median survival for patients is 15 months and the majority of patients experience disease recurrence within 6-8 months of treatment onset. Novel therapeutic approaches are urgently needed for both newly diagnosed and recurrent GBM patients. In this review, we summarise the current preclinical and clinical findings emphasising that CKIs could represent an exciting novel approach for GBM treatment.
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Affiliation(s)
- Viktorija Juric
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin D02, Ireland
| | - Brona Murphy
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin D02, Ireland
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43
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Ko CS, Kalakuntla P, Martin AC. Apical Constriction Reversal upon Mitotic Entry Underlies Different Morphogenetic Outcomes of Cell Division. Mol Biol Cell 2020; 31:1663-1674. [PMID: 32129704 PMCID: PMC7521848 DOI: 10.1091/mbc.e19-12-0673] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
During development, coordinated cell shape changes and cell divisions sculpt tissues. While these individual cell behaviors have been extensively studied, how cell shape changes and cell divisions that occur concurrently in epithelia influence tissue shape is less understood. We addressed this question in two contexts of the early Drosophila embryo: premature cell division during mesoderm invagination, and native ectodermal cell divisions with ectopic activation of apical contractility. Using quantitative live-cell imaging, we demonstrated that mitotic entry reverses apical contractility by interfering with medioapical RhoA signaling. While premature mitotic entry inhibits mesoderm invagination, which relies on apical constriction, mitotic entry in an artificially contractile ectoderm induced ectopic tissue invaginations. Ectopic invaginations resulted from medioapical myosin loss in neighboring mitotic cells. This myosin loss enabled nonmitotic cells to apically constrict through mitotic cell stretching. Thus, the spatial pattern of mitotic entry can differentially regulate tissue shape through signal interference between apical contractility and mitosis.
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Affiliation(s)
- Clint S Ko
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142
| | - Prateek Kalakuntla
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142
| | - Adam C Martin
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142
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44
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Lam CW, Fong NC, Chan TYC, Lau KC, Ling TK, Mak DWY, Cheng X, Law CY. Centrosome-associated CDC25B is a novel disease-causing gene for a syndrome with cataracts, dilated cardiomyopathy, and multiple endocrinopathies. Clin Chim Acta 2020; 504:81-87. [PMID: 32027886 DOI: 10.1016/j.cca.2020.01.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 01/07/2020] [Accepted: 01/17/2020] [Indexed: 11/16/2022]
Abstract
We describe a unique Chinese girl who presented with intrauterine growth retardation, delayed development, bilateral cataracts, hypothyroidism, growth hormone deficiency, and juvenile dilated cardiomyopathy. She was born to consanguineous parents with a history of one fetal and one infantile death in the family. She died from cardiac failure at the age of 12. In the pursuit of a diagnosis, the family was referred to the Clinics for Rare Diseases Referral and the University of Hong Kong Undiagnosed Disease Program. Whole-exome sequencing analysis revealed a homozygous non-sense variant, NM_021873:c.313G > T (p.Glu105*), in the CDC25B gene, a key regulator of the cell cycle. This variant was located in a region of homozygosity of 25 Mb on chromosome 20. Her parents and two asymptomatic sisters were confirmed to be carriers and one brother did not carry the variant. This is the first report of a natural human knockout of the CDC25B gene. Multiple endocrinopathies and fatal juvenile dilated cardiomyopathy suggests the potential for unfavorable complications in oncology patients receiving CDC25B inhibitors as an emerging targeted therapy.
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Affiliation(s)
- Ching-Wan Lam
- Department of Pathology, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China.
| | - Nai-Chung Fong
- Department of Paediatrics & Adolescent Medicine, Princess Margaret Hospital, Hong Kong, China
| | | | - Kwai-Cheung Lau
- Department of Pathology, Princess Margaret Hospital, Hong Kong, China
| | - Tsz-Ki Ling
- Division of Chemical Pathology, Department of Pathology, Queen Mary Hospital, Hong Kong, China
| | - Daniel Wai-Yau Mak
- Department of Paediatrics & Adolescent Medicine, Princess Margaret Hospital, Hong Kong, China
| | - Xinqi Cheng
- Department of Clinical Laboratory, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Chun-Yiu Law
- Division of Chemical Pathology, Department of Pathology, Queen Mary Hospital, Hong Kong, China
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45
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Opalko HE, Nasa I, Kettenbach AN, Moseley JB. A mechanism for how Cdr1/Nim1 kinase promotes mitotic entry by inhibiting Wee1. Mol Biol Cell 2019; 30:3015-3023. [PMID: 31644361 PMCID: PMC6880885 DOI: 10.1091/mbc.e19-08-0430] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
To enter into mitosis, cells must shut off the cell cycle inhibitor Wee1. SAD family protein kinases regulate Wee1 signaling in yeast and humans. In Schizosaccharomyces pombe, two SAD kinases (Cdr1/Nim1 and Cdr2) act as upstream inhibitors of Wee1. Previous studies found that S. pombe Cdr1/Nim1 directly phosphorylates and inhibits Wee1 in vitro, but different results were obtained for budding yeast and human SAD kinases. Without a full understanding of Cdr1 action on Wee1, it has been difficult to assess the in vivo relevance and conservation of this mechanism. Here, we show that both Cdr1 and Cdr2 promote Wee1 phosphorylation in cells, but only Cdr1 inhibits Wee1 kinase activity. Inhibition occurs when Cdr1 phosphorylates a cluster of serine residues linking α-helices G and H of the Wee1 kinase domain. This region is highly divergent among different Wee1 proteins, consistent with distinct regulatory mechanisms. A wee(4A) mutant that impairs phosphorylation by Cdr1 delays mitotic entry and causes elongated cells. By disrupting and retargeting Cdr1 localization, we show that Cdr1 inhibition of Wee1 occurs in cells at cortical nodes formed by Cdr2. On the basis of our results, we propose a two-step model for inhibition of Wee1 by Cdr1 and Cdr2 at nodes.
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Affiliation(s)
- Hannah E Opalko
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH 03755
| | - Isha Nasa
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH 03755.,Norris Cotton Cancer Center, The Geisel School of Medicine at Dartmouth, Lebanon, NH 03756
| | - Arminja N Kettenbach
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH 03755.,Norris Cotton Cancer Center, The Geisel School of Medicine at Dartmouth, Lebanon, NH 03756
| | - James B Moseley
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, NH 03755
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46
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Lewis CW, Bukhari AB, Xiao EJ, Choi WS, Smith JD, Homola E, Mackey JR, Campbell SD, Gamper AM, Chan GK. Upregulation of Myt1 Promotes Acquired Resistance of Cancer Cells to Wee1 Inhibition. Cancer Res 2019; 79:5971-5985. [PMID: 31594837 DOI: 10.1158/0008-5472.can-19-1961] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 09/04/2019] [Accepted: 10/04/2019] [Indexed: 11/16/2022]
Abstract
Adavosertib (also known as AZD1775 or MK1775) is a small-molecule inhibitor of the protein kinase Wee1, with single-agent activity in multiple solid tumors, including sarcoma, glioblastoma, and head and neck cancer. Adavosertib also shows promising results in combination with genotoxic agents such as ionizing radiation or chemotherapy. Previous studies have investigated molecular mechanisms of primary resistance to Wee1 inhibition. Here, we investigated mechanisms of acquired resistance to Wee1 inhibition, focusing on the role of the Wee1-related kinase Myt1. Myt1 and Wee1 kinases were both capable of phosphorylating and inhibiting Cdk1/cyclin B, the key enzymatic complex required for mitosis, demonstrating their functional redundancy. Ectopic activation of Cdk1 induced aberrant mitosis and cell death by mitotic catastrophe. Cancer cells with intrinsic adavosertib resistance had higher levels of Myt1 compared with sensitive cells. Furthermore, cancer cells that acquired resistance following short-term adavosertib treatment had higher levels of Myt1 compared with mock-treated cells. Downregulating Myt1 enhanced ectopic Cdk1 activity and restored sensitivity to adavosertib. These data demonstrate that upregulating Myt1 is a mechanism by which cancer cells acquire resistance to adavosertib. SIGNIFICANCE: Myt1 is a candidate predictive biomarker of acquired resistance to the Wee1 kinase inhibitor adavosertib.
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Affiliation(s)
- Cody W Lewis
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada.,Experimental Oncology, Cross Cancer Institute, Edmonton, Alberta, Canada.,Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, Alberta, Canada
| | - Amirali B Bukhari
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada.,Experimental Oncology, Cross Cancer Institute, Edmonton, Alberta, Canada.,Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, Alberta, Canada
| | - Edric J Xiao
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada.,Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, Alberta, Canada
| | - Won-Shik Choi
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada.,Experimental Oncology, Cross Cancer Institute, Edmonton, Alberta, Canada.,Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, Alberta, Canada
| | - Joanne D Smith
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada.,Experimental Oncology, Cross Cancer Institute, Edmonton, Alberta, Canada.,Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, Alberta, Canada
| | - Ellen Homola
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - John R Mackey
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada.,Medical Oncology, Cross Cancer Institute, Edmonton, Alberta, Canada
| | - Shelagh D Campbell
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Armin M Gamper
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada.,Experimental Oncology, Cross Cancer Institute, Edmonton, Alberta, Canada.,Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, Alberta, Canada
| | - Gordon K Chan
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada. .,Experimental Oncology, Cross Cancer Institute, Edmonton, Alberta, Canada.,Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, Alberta, Canada
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47
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Cerchia C, Nasso R, Mori M, Villa S, Gelain A, Capasso A, Aliotta F, Simonetti M, Rullo R, Masullo M, De Vendittis E, Ruocco MR, Lavecchia A. Discovery of Novel Naphthylphenylketone and Naphthylphenylamine Derivatives as Cell Division Cycle 25B (CDC25B) Phosphatase Inhibitors: Design, Synthesis, Inhibition Mechanism, and in Vitro Efficacy against Melanoma Cell Lines. J Med Chem 2019; 62:7089-7110. [PMID: 31294975 DOI: 10.1021/acs.jmedchem.9b00632] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
CDC25 phosphatases play a critical role in the regulation of the cell cycle and thus represent attractive cancer therapeutic targets. We previously discovered the 4-(2-carboxybenzoyl)phthalic acid (NSC28620) as a new CDC25 inhibitor endowed with promising anticancer activity in breast, prostate, and leukemia cells. Herein, we report a structure-based optimization of NSC28620, leading to the identification of a series of novel naphthylphenylketone and naphthylphenylamine derivatives as CDC25B inhibitors. Compounds 7j, 7i, 6e, 7f, and 3 showed higher inhibitory activity than the initial lead, with Ki values in the low micromolar range. Kinetic analysis, intrinsic fluorescence studies, and induced fit docking simulations provided a mechanistic understanding of the activity of these derivatives. All compounds were tested in the highly aggressive human melanoma cell lines A2058 and A375. Compound 4a potently inhibited cell proliferation and colony formation, causing an increase of the G2/M phase and a reduction of the G0/G1 phase of the cell cycle in both cell lines.
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Affiliation(s)
- Carmen Cerchia
- Department of Pharmacy, "Drug Discovery" Laboratory , University of Naples Federico II , Via D. Montesano, 49 , 80131 Naples , Italy
| | - Rosarita Nasso
- Department of Molecular Medicine and Medical Biotechnology , University of Naples Federico II , Via S. Pansini 5 , 80131 Naples , Italy.,Department of Movement Sciences and Wellness , University of Naples "Parthenope" , 80133 Naples , Italy
| | - Matteo Mori
- Department of Pharmaceutical Sciences , University of Milan , Via Mangiagalli, 25 , 20133 Milan , Italy
| | - Stefania Villa
- Department of Pharmaceutical Sciences , University of Milan , Via Mangiagalli, 25 , 20133 Milan , Italy
| | - Arianna Gelain
- Department of Pharmaceutical Sciences , University of Milan , Via Mangiagalli, 25 , 20133 Milan , Italy
| | - Alessandra Capasso
- Department of Molecular Medicine and Medical Biotechnology , University of Naples Federico II , Via S. Pansini 5 , 80131 Naples , Italy
| | - Federica Aliotta
- Department of Molecular Medicine and Medical Biotechnology , University of Naples Federico II , Via S. Pansini 5 , 80131 Naples , Italy
| | - Martina Simonetti
- Department of Molecular Medicine and Medical Biotechnology , University of Naples Federico II , Via S. Pansini 5 , 80131 Naples , Italy
| | - Rosario Rullo
- Department of Molecular Medicine and Medical Biotechnology , University of Naples Federico II , Via S. Pansini 5 , 80131 Naples , Italy.,Institute for the Animal Production Systems in the Mediterranean Environment , Via Argine 1085 , 80147 Naples , Italy
| | - Mariorosario Masullo
- Department of Movement Sciences and Wellness , University of Naples "Parthenope" , 80133 Naples , Italy
| | - Emmanuele De Vendittis
- Department of Molecular Medicine and Medical Biotechnology , University of Naples Federico II , Via S. Pansini 5 , 80131 Naples , Italy
| | - Maria Rosaria Ruocco
- Department of Molecular Medicine and Medical Biotechnology , University of Naples Federico II , Via S. Pansini 5 , 80131 Naples , Italy
| | - Antonio Lavecchia
- Department of Pharmacy, "Drug Discovery" Laboratory , University of Naples Federico II , Via D. Montesano, 49 , 80131 Naples , Italy
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48
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Siciliano I, Lentz Grønlund A, Ševčíková H, Spadafora ND, Rafiei G, Francis D, Herbert RJ, Bitonti MB, Rogers HJ, Lipavská H. Expression of Arabidopsis WEE1 in tobacco induces unexpected morphological and developmental changes. Sci Rep 2019; 9:8695. [PMID: 31213651 PMCID: PMC6581958 DOI: 10.1038/s41598-019-45015-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 05/24/2019] [Indexed: 11/08/2022] Open
Abstract
WEE1 regulates the cell cycle by inactivating cyclin dependent protein kinases (CDKs) via phosphorylation. In yeast and animal cells, CDC25 phosphatase dephosphorylates the CDK releasing cells into mitosis, but in plants, its role is less clear. Expression of fission yeast CDC25 (Spcdc25) in tobacco results in small cell size, premature flowering and increased shoot morphogenetic capacity in culture. When Arath;WEE1 is over-expressed in Arabidopsis, root apical meristem cell size increases, and morphogenetic capacity of cultured hypocotyls is reduced. However expression of Arath;WEE1 in tobacco plants resulted in precocious flowering and increased shoot morphogenesis of stem explants, and in BY2 cultures cell size was reduced. This phenotype is similar to expression of Spcdc25 and is consistent with a dominant negative effect on WEE1 action. Consistent with this putative mechanism, WEE1 protein levels fell and CDKB levels rose prematurely, coinciding with early mitosis. The phenotype is not due to sense-mediated silencing of WEE1, as overall levels of WEE1 transcript were not reduced in BY2 lines expressing Arath;WEE1. However the pattern of native WEE1 transcript accumulation through the cell cycle was altered by Arath;WEE1 expression, suggesting feedback inhibition of native WEE1 transcription.
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Affiliation(s)
- Ilario Siciliano
- School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AT, UK
- School of Science and the Environment, University of Worcester, Henwick Grove, Worcester, WR2 6AJ, UK
| | - Anne Lentz Grønlund
- School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AT, UK
| | - Hana Ševčíková
- Department of Experimental Plant Biology, Charles University, Faculty of Science, Viničná 5, 128 43, Praha 2, Czech Republic
| | - Natasha D Spadafora
- School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AT, UK
- School of Science and the Environment, University of Worcester, Henwick Grove, Worcester, WR2 6AJ, UK
| | - Golnaz Rafiei
- School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AT, UK
| | - Dennis Francis
- School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AT, UK
| | - Robert J Herbert
- School of Science and the Environment, University of Worcester, Henwick Grove, Worcester, WR2 6AJ, UK
| | - M Beatrice Bitonti
- Department of Biology, Ecology and Earth Sciences, University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - Hilary J Rogers
- School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AT, UK.
| | - Helena Lipavská
- Department of Experimental Plant Biology, Charles University, Faculty of Science, Viničná 5, 128 43, Praha 2, Czech Republic
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49
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Abstract
Cell division is a highly regulated and carefully orchestrated process. Understanding the mechanisms that promote proper cell division is an important step toward unraveling important questions in cell biology and human health. Early studies seeking to dissect the mechanisms of cell division used classical genetics approaches to identify genes involved in mitosis and deployed biochemical approaches to isolate and identify proteins critical for cell division. These studies underscored that post-translational modifications and cyclin-kinase complexes play roles at the heart of the cell division program. Modern approaches for examining the mechanisms of cell division, including the use of high-throughput methods to study the effects of RNAi, cDNA, and chemical libraries, have evolved to encompass a larger biological and chemical space. Here, we outline some of the classical studies that established a foundation for the field and provide an overview of recent approaches that have advanced the study of cell division.
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Affiliation(s)
- Joseph Y Ong
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095
| | - Jorge Z Torres
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095 .,The Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, California 90095.,Molecular Biology Institute, UCLA, Los Angeles, California 90095
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50
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Allard CAH, Opalko HE, Moseley JB. Stable Pom1 clusters form a glucose-modulated concentration gradient that regulates mitotic entry. eLife 2019; 8:e46003. [PMID: 31050341 PMCID: PMC6524964 DOI: 10.7554/elife.46003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 05/02/2019] [Indexed: 12/12/2022] Open
Abstract
Control of cell size requires molecular size sensors that are coupled to the cell cycle. Rod-shaped fission yeast cells divide at a threshold size partly due to Cdr2 kinase, which forms nodes at the medial cell cortex where it inhibits the Cdk1-inhibitor Wee1. Pom1 kinase phosphorylates and inhibits Cdr2, and forms cortical concentration gradients from cell poles. Pom1 inhibits Cdr2 signaling to Wee1 specifically in small cells, but the time and place of their regulatory interactions were unclear. We show that Pom1 forms stable oligomeric clusters that dynamically sample the cell cortex. Binding frequency is patterned into a concentration gradient by the polarity landmarks Tea1 and Tea4. Pom1 clusters colocalize with Cdr2 nodes, forming a glucose-modulated inhibitory threshold against node activation. Our work reveals how Pom1-Cdr2-Wee1 operates in multiprotein clusters at the cortex to promote mitotic entry at a cell size that can be modified by nutrient availability.
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Affiliation(s)
- Corey A H Allard
- Department of Biochemistry and Cell BiologyThe Geisel School of Medicine at DartmouthHanoverUnited States
| | - Hannah E Opalko
- Department of Biochemistry and Cell BiologyThe Geisel School of Medicine at DartmouthHanoverUnited States
| | - James B Moseley
- Department of Biochemistry and Cell BiologyThe Geisel School of Medicine at DartmouthHanoverUnited States
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