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Xu J, Smith L. Curating models from BioModels: Developing a workflow for creating OMEX files. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.15.585236. [PMID: 38559029 PMCID: PMC10979985 DOI: 10.1101/2024.03.15.585236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
The reproducibility of computational biology models can be greatly facilitated by widely adopted standards and public repositories. We examined 50 models from the BioModels Database and attempted to validate the original curation and correct some of them if necessary. For each model, we reproduced these published results using Tellurium. Once reproduced we manually created a new set of files, with the model information stored by the Systems Biology Markup Language (SBML), and simulation instructions stored by the Simulation Experiment Description Markup Language (SED-ML), and everything included in an Open Modeling EXchange (OMEX) file, which could be used with a variety of simulators to reproduce the same results. On the one hand, the reproducibility procedure of 50 models developed a manual workflow that we would use to build an automatic platform to help users more easily curate and verify models in the future. On the other hand, these exercises allowed us to find the limitations and possible enhancement of the current curation and tooling to verify and curate models.
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DeMarco AG, Dibble MG, Hall MC. Inducible degradation-coupled phosphoproteomics identifies PP2A Rts1 as a novel eisosome regulator. Front Cell Dev Biol 2024; 12:1451027. [PMID: 39234563 PMCID: PMC11371571 DOI: 10.3389/fcell.2024.1451027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2024] [Accepted: 08/02/2024] [Indexed: 09/06/2024] Open
Abstract
Introduction Reversible protein phosphorylation is an abundant post-translational modification dynamically regulated by opposing kinases and phosphatases. Protein phosphorylation has been extensively studied in cell division, where waves of cyclin-dependent kinase activity, peaking in mitosis, drive the sequential stages of the cell cycle. Here we developed and employed a strategy to specifically probe kinase or phosphatase substrates at desired times or experimental conditions in the model organism Saccharomyces cerevisiae. Methods We combined auxin-inducible degradation (AID) with mass spectrometry-based phosphoproteomics, which allowed us to arrest physiologically normal cultures in mitosis prior to rapid phosphatase degradation and phosphoproteome analysis. Results and discussion Our results revealed that protein phosphatase 2A coupled with its B56 regulatory subunit, Rts1 (PP2ARts1), is involved in dephosphorylation of numerous proteins in mitosis, highlighting the need for phosphatases to selectively maintain certain proteins in a hypophosphorylated state in the face of high mitotic kinase activity. Unexpectedly, we observed elevated phosphorylation at many sites on several subunits of the fungal eisosome complex following rapid Rts1 degradation. Eisosomes are dynamic polymeric assemblies that create furrows in the plasma membrane important in regulating nutrient import, lipid metabolism, and stress responses, among other things. We found that PP2ARts1-mediated dephosphorylation of eisosomes promotes their plasma membrane association and we provide evidence that this regulation impacts eisosome roles in metabolic homeostasis. The combination of rapid, inducible protein degradation with proteomic profiling offers several advantages over common protein disruption methods for characterizing substrates of regulatory enzymes involved in dynamic biological processes.
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Affiliation(s)
- Andrew G DeMarco
- Department of Biochemistry, Purdue University, West Lafayette, IN, United States
| | - Marcella G Dibble
- Department of Biochemistry, Purdue University, West Lafayette, IN, United States
| | - Mark C Hall
- Department of Biochemistry, Purdue University, West Lafayette, IN, United States
- Institute for Cancer Research, Purdue University, West Lafayette, IN, United States
- Institute for Drug Discovery, Purdue University, West Lafayette, IN, United States
- Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN, United States
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Ravi J, Samart K, Zwolak J. Modeling the START transition in the budding yeast cell cycle. PLoS Comput Biol 2024; 20:e1012048. [PMID: 39093881 PMCID: PMC11324117 DOI: 10.1371/journal.pcbi.1012048] [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: 11/12/2023] [Revised: 08/14/2024] [Accepted: 04/02/2024] [Indexed: 08/04/2024] Open
Abstract
Budding yeast, Saccharomyces cerevisiae, is widely used as a model organism to study the genetics underlying eukaryotic cellular processes and growth critical to cancer development, such as cell division and cell cycle progression. The budding yeast cell cycle is also one of the best-studied dynamical systems owing to its thoroughly resolved genetics. However, the dynamics underlying the crucial cell cycle decision point called the START transition, at which the cell commits to a new round of DNA replication and cell division, are under-studied. The START machinery involves a central cyclin-dependent kinase; cyclins responsible for starting the transition, bud formation, and initiating DNA synthesis; and their transcriptional regulators. However, evidence has shown that the mechanism is more complicated than a simple irreversible transition switch. Activating a key transcription regulator SBF requires the phosphorylation of its inhibitor, Whi5, or an SBF/MBF monomeric component, Swi6, but not necessarily both. Also, the timing and mechanism of the inhibitor Whi5's nuclear export, while important, are not critical for the timing and execution of START. Therefore, there is a need for a consolidated model for the budding yeast START transition, reconciling regulatory and spatial dynamics. We built a detailed mathematical model (START-BYCC) for the START transition in the budding yeast cell cycle based on established molecular interactions and experimental phenotypes. START-BYCC recapitulates the underlying dynamics and correctly emulates key phenotypic traits of ~150 known START mutants, including regulation of size control, localization of inhibitor/transcription factor complexes, and the nutritional effects on size control. Such a detailed mechanistic understanding of the underlying dynamics gets us closer towards deconvoluting the aberrant cellular development in cancer.
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Affiliation(s)
- Janani Ravi
- Department of Biomedical Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
| | - Kewalin Samart
- Department of Biomedical Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
- Computational Bioscience program, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
| | - Jason Zwolak
- InSilica Labs, Asheville, North Carolina, United States of America
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Gutierrez-Morton E, Haluska C, Collins L, Rizkallah R, Tomko RJ, Wang Y. The polySUMOylation axis promotes nucleolar release of Tof2 for mitotic exit. Cell Rep 2024; 43:114492. [PMID: 39002125 PMCID: PMC11298248 DOI: 10.1016/j.celrep.2024.114492] [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: 12/22/2023] [Revised: 05/02/2024] [Accepted: 06/26/2024] [Indexed: 07/15/2024] Open
Abstract
In budding yeast, the nucleolus serves as the site to sequester Cdc14, a phosphatase essential for mitotic exit. Nucleolar proteins Tof2, Net1, and Fob1 are required for this sequestration. Although it is known that these nucleolar proteins are SUMOylated, how SUMOylation regulates their activity remains unknown. Here, we show that Tof2 exhibits cell-cycle-regulated nucleolar delocalization and turnover. Depletion of the nuclear small ubiquitin-like modifier (SUMO) protease Ulp2 not only causes Tof2 polySUMOylation, nucleolar delocalization, and degradation but also leads to Cdc14 nucleolar release and activation. This outcome depends on polySUMOylation and the activity of downstream enzymes, including SUMO-targeted ubiquitin ligase and Cdc48/p97 segregase. We further developed a system to tether SUMO machinery to Tof2 and generated a SUMO-deficient tof2 mutant, and the results indicate that Tof2 polySUMOylation is necessary and sufficient for its nucleolar delocalization and degradation. Together, our work reveals a polySUMO-dependent mechanism that delocalizes Tof2 from the nucleolus to facilitate mitotic exit.
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Affiliation(s)
- Emily Gutierrez-Morton
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306, USA
| | - Cory Haluska
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Liam Collins
- College of Arts and Sciences, Florida State University, Tallahassee, FL 32306, USA
| | - Raed Rizkallah
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306, USA
| | - Robert J Tomko
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306, USA
| | - Yanchang Wang
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306, USA.
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5
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Durant M, Mucelli X, Huang LS. Meiotic Cytokinesis in Saccharomyces cerevisiae: Spores That Just Need Closure. J Fungi (Basel) 2024; 10:132. [PMID: 38392804 PMCID: PMC10890087 DOI: 10.3390/jof10020132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 01/30/2024] [Accepted: 02/04/2024] [Indexed: 02/24/2024] Open
Abstract
In the budding yeast Saccharomyces cerevisiae, sporulation occurs during starvation of a diploid cell and results in the formation of four haploid spores forming within the mother cell ascus. Meiosis divides the genetic material that is encapsulated by the prospore membrane that grows to surround the haploid nuclei; this membrane will eventually become the plasma membrane of the haploid spore. Cellularization of the spores occurs when the prospore membrane closes to capture the haploid nucleus along with some cytoplasmic material from the mother cell, and thus, closure of the prospore membrane is the meiotic cytokinetic event. This cytokinetic event involves the removal of the leading-edge protein complex, a complex of proteins that localizes to the leading edge of the growing prospore membrane. The development and closure of the prospore membrane must be coordinated with other meiotic exit events such as spindle disassembly. Timing of the closure of the prospore membrane depends on the meiotic exit pathway, which utilizes Cdc15, a Hippo-like kinase, and Sps1, an STE20 family GCKIII kinase, acting in parallel to the E3 ligase Ama1-APC/C. This review describes the sporulation process and focuses on the development of the prospore membrane and the regulation of prospore membrane closure.
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Affiliation(s)
- Matthew Durant
- Department of Biology, University of Massachusetts Boston, Boston, MA 02125, USA
| | - Xheni Mucelli
- Department of Biology, University of Massachusetts Boston, Boston, MA 02125, USA
| | - Linda S Huang
- Department of Biology, University of Massachusetts Boston, Boston, MA 02125, USA
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6
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DeMarco AG, Dibble MG, Hall MC. Inducible degradation-coupled phosphoproteomics identifies PP2A Rts1 as a novel eisosome regulator. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.24.563668. [PMID: 37961087 PMCID: PMC10634780 DOI: 10.1101/2023.10.24.563668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Reversible protein phosphorylation is an abundant post-translational modification dynamically regulated by opposing kinases and phosphatases. Protein phosphorylation has been extensively studied in cell division, where waves of cyclin-dependent kinase activity, peaking in mitosis, drive the sequential stages of the cell cycle. Here we developed and employed a strategy to specifically probe kinase or phosphatase substrates at desired times or experimental conditions in the model organism Saccharomyces cerevisiae. We combined auxin-inducible degradation (AID) with mass spectrometry-based phosphoproteomics, which allowed us to arrest physiologically normal cultures in mitosis prior to rapid phosphatase degradation and phosphoproteome analysis. Our results revealed that protein phosphatase 2A coupled with its B56 regulatory subunit, Rts1 (PP2ARts1), is involved in dephosphorylation of numerous proteins in mitosis, highlighting the need for phosphatases to selectively maintain certain proteins in a hypophosphorylated state in the face of high mitotic kinase activity. Unexpectedly, we observed elevated phosphorylation at many sites on several subunits of the fungal eisosome complex following rapid Rts1 degradation. Eisosomes are dynamic polymeric assemblies that create furrows in the plasma membrane important in regulating nutrient import, lipid metabolism, and stress responses, among other things. We found that PP2ARts1-mediated dephosphorylation of eisosomes promotes their plasma membrane association and we provide evidence that this regulation impacts eisosome roles in metabolic homeostasis. The combination of rapid, inducible protein degradation with proteomic profiling offers several advantages over common protein disruption methods for characterizing substrates of regulatory enzymes involved in dynamic biological processes.
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Affiliation(s)
- Andrew G. DeMarco
- Department of Biochemistry, Purdue University, West Lafayette, IN, 47907
| | - Marcella G. Dibble
- Department of Biochemistry, Purdue University, West Lafayette, IN, 47907
| | - Mark C. Hall
- Department of Biochemistry, Purdue University, West Lafayette, IN, 47907
- Institute for Cancer Research, Purdue University, West Lafayette, IN, 47907
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7
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Keaton JM, Workman BG, Xie L, Paulson JR. Analog-sensitive Cdk1 as a tool to study mitotic exit: protein phosphatase 1 is required downstream from Cdk1 inactivation in budding yeast. Chromosome Res 2023; 31:27. [PMID: 37690059 DOI: 10.1007/s10577-023-09736-6] [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: 04/06/2023] [Revised: 08/17/2023] [Accepted: 08/23/2023] [Indexed: 09/12/2023]
Abstract
We show that specific inactivation of the protein kinase Cdk1/cyclin B (Cdc28/Clb2) triggers exit from mitosis in the budding yeast Saccharomyces cerevisiae. Cells carrying the allele cdc28-as1, which makes Cdk1 (Cdc28) uniquely sensitive to the ATP analog 1NM-PP1, were arrested with spindle poisons and then treated with 1NM-PP1 to inhibit Cdk1. This caused the cells to leave mitosis and enter G1-phase as shown by initiation of rebudding (without cytokinesis), induction of mating projections ("shmoos") by α-factor, stabilization of Sic1, and degradation of Clb2. It is known that Cdk1 must be inactivated for cells to exit mitosis, but our results show that inactivation of Cdk1 is not only necessary but also sufficient to initiate the transition from mitosis to G1-phase. This result suggests a system in which to test requirements for particular gene products downstream from Cdk1 inactivation, for example, by combining cdc28-as1 with conditional mutations in the genes of interest. Using this approach, we demonstrate that protein phosphatase 1 (PPase1; Glc7 in S. cerevisiae) is required for mitotic exit and reestablishment of interphase following Cdk1 inactivation. This system could be used to test the need for other protein phosphatases downstream from Cdk1 inactivation, such as PPase 2A and Cdc14, and it could be combined with phosphoproteomics to gain information about the substrates that the various phosphatases act upon during mitotic exit.
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Affiliation(s)
- Jason M Keaton
- Acacia Safety Consulting, Inc, P.O. Box 342603, Milwaukee, WI, 53234, USA
- Department of Chemistry, University of Wisconsin-Oshkosh, Oshkosh, WI, 54901, USA
| | - Benjamin G Workman
- Department of Chemistry, University of Wisconsin-Oshkosh, Oshkosh, WI, 54901, USA
| | - Linfeng Xie
- Department of Chemistry, University of Wisconsin-Oshkosh, Oshkosh, WI, 54901, USA
| | - James R Paulson
- Department of Chemistry, University of Wisconsin-Oshkosh, Oshkosh, WI, 54901, USA.
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8
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Sherwin D, Gutierrez-Morton E, Bokros M, Haluska C, Wang Y. A new layer of regulation of chromosomal passenger complex (CPC) translocation in budding yeast. Mol Biol Cell 2023; 34:ar97. [PMID: 37405742 PMCID: PMC10551702 DOI: 10.1091/mbc.e23-02-0063] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 06/27/2023] [Accepted: 06/28/2023] [Indexed: 07/06/2023] Open
Abstract
The conserved chromosomal passenger complex (CPC) consists of Ipl1Aurora-B, Sli15INCENP, Bir1Survivin, and Nbl1Borealin, and localizes at the kinetochore/centromere to correct kinetochore attachment errors and to prevent checkpoint silencing. After anaphase entry, the CPC moves from the kinetochore/centromere to the spindle. In budding yeast, CPC subunit Sli15 is phosphorylated by both cyclin-dependent kinase (CDK) and Ipl1 kinase. Following anaphase onset, activated Cdc14 phosphatase reverses Sli15 phosphorylation imposed by CDK to promote CPC translocation. Although abolished Sli15 phosphorylation imposed by Ipl1 also causes CPC translocation, the regulation of Ipl1-imposed Sli15 phosphorylation remains unclear. In addition to Sli15, Cdc14 also dephosphorylates Fin1, a regulatory subunit of protein phosphatase 1 (PP1), to enable kinetochore localization of Fin1-PP1. Here, we present evidence supporting the notion that kinetochore-localized Fin1-PP1 likely reverses Ipl1-imposed Sli15 phosphorylation to promote CPC translocation from the kinetochore/centromere to the spindle. Importantly, premature Fin1 kinetochore localization or phospho-deficient sli15 mutation causes checkpoint defects in response to tensionless attachments, resulting in chromosome missegregation. In addition, our data indicate that reversion of CDK- and Ipl1-imposed Sli15 phosphorylation shows an additive effect on CPC translocation. Together, these results reveal a previously unidentified pathway to regulate CPC translocation, which is important for accurate chromosome segregation.
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Affiliation(s)
- Delaney Sherwin
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306-4300
| | - Emily Gutierrez-Morton
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306-4300
| | - Michael Bokros
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306-4300
| | - Cory Haluska
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306-4300
| | - Yanchang Wang
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306-4300
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9
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Foltman M, Mendez I, Bech-Serra JJ, de la Torre C, Brace JL, Weiss EL, Lucas M, Queralt E, Sanchez-Diaz A. TOR complex 1 negatively regulates NDR kinase Cbk1 to control cell separation in budding yeast. PLoS Biol 2023; 21:e3002263. [PMID: 37647291 PMCID: PMC10468069 DOI: 10.1371/journal.pbio.3002263] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 07/19/2023] [Indexed: 09/01/2023] Open
Abstract
The target of rapamycin (TOR) signalling pathway plays a key role in the coordination between cellular growth and the cell cycle machinery in eukaryotes. The underlying molecular mechanisms by which TOR might regulate events after anaphase remain unknown. We show for the first time that one of the 2 TOR complexes in budding yeast, TORC1, blocks the separation of cells following cytokinesis by phosphorylation of a member of the NDR (nuclear Dbf2-related) protein-kinase family, the protein Cbk1. We observe that TORC1 alters the phosphorylation pattern of Cbk1 and we identify a residue within Cbk1 activation loop, T574, for which a phosphomimetic substitution makes Cbk1 catalytically inactive and, indeed, reproduces TORC1 control over cell separation. In addition, we identify the exocyst component Sec3 as a key substrate of Cbk1, since Sec3 activates the SNARE complex to promote membrane fusion. TORC1 activity ultimately compromises the interaction between Sec3 and a t-SNARE component. Our data indicate that TORC1 negatively regulates cell separation in budding yeast by participating in Cbk1 phosphorylation, which in turn controls the fusion of secretory vesicles transporting hydrolase at the site of division.
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Affiliation(s)
- Magdalena Foltman
- Mechanisms and Regulation of Cell Division Research Unit, Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-CSIC, Santander, Spain
- Departamento de Biología Molecular, Facultad de Medicina, Universidad de Cantabria, Santander, Spain
| | - Iván Mendez
- Departamento de Biología Molecular, Facultad de Medicina, Universidad de Cantabria, Santander, Spain
- Structural Biology of Macromolecular Complexes Research Unit, Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-CSIC, Santander, Spain
| | - Joan J. Bech-Serra
- Josep Carreras Leukaemia Research Institute, IJC Building, Campus ICO-Germans Trias i Pujol, Barcelona, Spain
| | - Carolina de la Torre
- Josep Carreras Leukaemia Research Institute, IJC Building, Campus ICO-Germans Trias i Pujol, Barcelona, Spain
| | - Jennifer L. Brace
- Department of Biochemistry, Molecular Biology, and Cell Biology, Northwestern University, Evanston, Illinois, United States of America
| | - Eric L. Weiss
- Department of Biochemistry, Molecular Biology, and Cell Biology, Northwestern University, Evanston, Illinois, United States of America
| | - María Lucas
- Departamento de Biología Molecular, Facultad de Medicina, Universidad de Cantabria, Santander, Spain
- Structural Biology of Macromolecular Complexes Research Unit, Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-CSIC, Santander, Spain
| | - Ethel Queralt
- Instituto de Biomedicina de Valencia (IBV-CSIC), Valencia, Spain
| | - Alberto Sanchez-Diaz
- Mechanisms and Regulation of Cell Division Research Unit, Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-CSIC, Santander, Spain
- Departamento de Biología Molecular, Facultad de Medicina, Universidad de Cantabria, Santander, Spain
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10
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El Dika M, Dudka D, Kloc M, Kubiak JZ. CDC6 as a Key Inhibitory Regulator of CDK1 Activation Dynamics and the Timing of Mitotic Entry and Progression. BIOLOGY 2023; 12:855. [PMID: 37372141 DOI: 10.3390/biology12060855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 06/08/2023] [Accepted: 06/09/2023] [Indexed: 06/29/2023]
Abstract
Timely mitosis is critically important for early embryo development. It is regulated by the activity of the conserved protein kinase CDK1. The dynamics of CDK1 activation must be precisely controlled to assure physiologic and timely entry into mitosis. Recently, a known S-phase regulator CDC6 emerged as a key player in mitotic CDK1 activation cascade in early embryonic divisions, operating together with Xic1 as a CDK1 inhibitor upstream of the Aurora A and PLK1, both CDK1 activators. Herein, we review the molecular mechanisms that underlie the control of mitotic timing, with special emphasis on how CDC6/Xic1 function impacts CDK1 regulatory network in the Xenopus system. We focus on the presence of two independent mechanisms inhibiting the dynamics of CDK1 activation, namely Wee1/Myt1- and CDC6/Xic1-dependent, and how they cooperate with CDK1-activating mechanisms. As a result, we propose a comprehensive model integrating CDC6/Xic1-dependent inhibition into the CDK1-activation cascade. The physiological dynamics of CDK1 activation appear to be controlled by the system of multiple inhibitors and activators, and their integrated modulation ensures concomitantly both the robustness and certain flexibility of the control of this process. Identification of multiple activators and inhibitors of CDK1 upon M-phase entry allows for a better understanding of why cells divide at a specific time and how the pathways involved in the timely regulation of cell division are all integrated to precisely tune the control of mitotic events.
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Affiliation(s)
- Mohammed El Dika
- Department of Biochemistry, Larner College of Medicine, UVM Cancer Center, University of Vermont, Burlington, VT 05405, USA
| | - Damian Dudka
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Malgorzata Kloc
- The Houston Methodist Research Institute, Transplant Immunology, Houston, TX 77030, USA
- Department of Surgery, The Houston Methodist Hospital, Houston, TX 77030, USA
- Department of Genetics, MD Anderson Cancer Center, The University of Texas, Houston, TX 77030, USA
| | - Jacek Z Kubiak
- Laboratory of Molecular Oncology and Innovative Therapies, Military Institute of Medicine-National Research Institute (WIM-PIB), Szaserow 128, 04-141 Warsaw, Poland
- Dynamics and Mechanics of Epithelia Group, Faculty of Medicine, Institute of Genetics and Development of Rennes, University of Rennes, CNRS, UMR 6290, 35043 Rennes, France
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11
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Keaton JM, Workman BG, Xie L, Paulson JR. Exit from Mitosis in Budding Yeast: Protein Phosphatase 1 is Required Downstream from Cdk1 Inactivation. RESEARCH SQUARE 2023:rs.3.rs-2787001. [PMID: 37090579 PMCID: PMC10120774 DOI: 10.21203/rs.3.rs-2787001/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
We show that inactivation of the protein kinase Cdk1/Cyclin B (Cdc28/Clb 2 in the budding yeast Saccharomyces cerevisiae ) is not only necessary for cells to leave mitosis, as is well known, but also sufficient to trigger mitotic exit. Cells carrying the mutation cdc28-as1 , which makes Cdc28 (Cdk1) uniquely sensitive to the ATP analog 1NM-PP1, were arrested with spindle poisons and then treated with 1NM-PP1 to inhibit Cdk1. This treatment caused the cells to exit mitosis and enter G1-phase as shown by initiation of rebudding (without cytokinesis), production of "shmoos" (when α-factor was present), stabilization of Sic1, and degradation of Clb2. This result provides a system in which to test whether particular gene products are required downstream from Cdk1 inactivation in exit from mitosis. In this system, the mutation cdc28-as1 is combined with a conditional mutation in the gene of interest. Using this approach, we demonstrate that Protein Phosphatase 1 (PPase1; Glc7 in S. cerevisiae ) is required for reestablishment of G1-phase following Cdk1 inactivation. This system could be used to test whether other protein phosphatases are also needed downstream from Cdk1 inactivation, and it could be combined with phosphoproteomics to gain information about the substrates those phosphatases act on during mitotic exit.
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12
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Coutelier H, Ilioaia O, Le Peillet J, Hamon M, D’Amours D, Teixeira MT, Xu Z. The Polo kinase Cdc5 is regulated at multiple levels in the adaptation response to telomere dysfunction. Genetics 2022; 223:6808627. [PMID: 36342193 PMCID: PMC9836022 DOI: 10.1093/genetics/iyac171] [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: 06/24/2022] [Accepted: 11/02/2022] [Indexed: 11/09/2022] Open
Abstract
Telomere dysfunction activates the DNA damage checkpoint to induce a cell cycle arrest. After an extended period of time, however, cells can bypass the arrest and undergo cell division despite the persistence of the initial damage, a process called adaptation to DNA damage. The Polo kinase Cdc5 in Saccharomyces cerevisiae is essential for adaptation and for many other cell cycle processes. How the regulation of Cdc5 in response to telomere dysfunction relates to adaptation is not clear. Here, we report that Cdc5 protein level decreases after telomere dysfunction in a Mec1-, Rad53- and Ndd1-dependent manner. This regulation of Cdc5 is important to maintain long-term cell cycle arrest but not for the initial checkpoint arrest. We find that both Cdc5 and the adaptation-deficient mutant protein Cdc5-ad are heavily phosphorylated and several phosphorylation sites modulate adaptation efficiency. The PP2A phosphatases are involved in Cdc5-ad phosphorylation status and contribute to adaptation mechanisms. We finally propose that Cdc5 orchestrates multiple cell cycle pathways to promote adaptation.
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Affiliation(s)
| | | | | | - Marion Hamon
- Sorbonne Université, PSL, CNRS, FR550, Institut de Biologie Physico-Chimique, 75005 Paris, France
| | - Damien D’Amours
- Ottawa Institute of Systems Biology, Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Maria Teresa Teixeira
- Sorbonne Université, PSL, CNRS, UMR8226, Institut de Biologie Physico-Chimique, Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes, 75005 Paris, France
| | - Zhou Xu
- Corresponding author: Sorbonne Université, CNRS, UMR7238, Institut de Biologie Paris‐Seine, Laboratory of Computational and Quantitative Biology, 75005 Paris, France.
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13
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Boukaba A, Wu Q, Liu J, Chen C, Liang J, Li J, Strunnikov A. Mapping separase-mediated cleavage in situ. NAR Genom Bioinform 2022; 4:lqac085. [PMID: 36415827 PMCID: PMC9673495 DOI: 10.1093/nargab/lqac085] [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: 05/26/2022] [Revised: 10/13/2022] [Accepted: 10/25/2022] [Indexed: 11/21/2022] Open
Abstract
Separase is a protease that performs critical functions in the maintenance of genetic homeostasis. Among them, the cleavage of the meiotic cohesin during meiosis is a key step in producing gametes in eukaryotes. However, the exact chromosomal localization of this proteolytic cleavage was not addressed due to the lack of experimental tools. To this end, we developed a method based on monoclonal antibodies capable of recognizing the predicted neo-epitopes produced by separase-mediated proteolysis in the RAD21 and REC8 cohesin subunits. To validate the epigenomic strategy of mapping cohesin proteolysis, anti-RAD21 neo-epitopes antibodies were used in ChIP-On-ChEPseq analysis of human cells undergoing mitotic anaphase. Second, a similar analysis applied for mapping of REC8 cleavage in germline cells in Macaque showed a correlation with a subset of alpha-satellites and other repeats, directly demonstrating that the site-specific mei-cohesin proteolysis hotspots are coincident but not identical with centromeres. The sequences for the corresponding immunoglobulin genes show a convergence of antibodies with close specificity. This approach could be potentially used to investigate cohesin ring opening events in other chromosomal locations, if applied to single cells.
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Affiliation(s)
- Abdelhalim Boukaba
- Molecular Epigenetics Laboratory, Guangzhou Institutes of Biomedicine and Health , Guangzhou , Guangdong , 510530 , China
| | - Qiongfang Wu
- Molecular Epigenetics Laboratory, Guangzhou Institutes of Biomedicine and Health , Guangzhou , Guangdong , 510530 , China
| | - Jian Liu
- Molecular Epigenetics Laboratory, Guangzhou Institutes of Biomedicine and Health , Guangzhou , Guangdong , 510530 , China
| | - Cheng Chen
- Molecular Epigenetics Laboratory, Guangzhou Institutes of Biomedicine and Health , Guangzhou , Guangdong , 510530 , China
| | - Jierong Liang
- Molecular Epigenetics Laboratory, Guangzhou Institutes of Biomedicine and Health , Guangzhou , Guangdong , 510530 , China
| | - Jingjing Li
- Molecular Epigenetics Laboratory, Guangzhou Institutes of Biomedicine and Health , Guangzhou , Guangdong , 510530 , China
| | - Alexander V Strunnikov
- Molecular Epigenetics Laboratory, Guangzhou Institutes of Biomedicine and Health , Guangzhou , Guangdong , 510530 , China
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14
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Deng DJ, Wang X, Yue KY, Wang Y, Jin QW. Analysis of the potential role of fission yeast PP2A in spindle assembly checkpoint inactivation. FASEB J 2022; 36:e22524. [PMID: 36006032 DOI: 10.1096/fj.202101884r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 07/26/2022] [Accepted: 08/17/2022] [Indexed: 11/11/2022]
Abstract
As a surveillance mechanism, the activated spindle assembly checkpoint (SAC) potently inhibits the E3 ubiquitin ligase APC/C (anaphase-promoting complex/cyclosome) to ensure accurate chromosome segregation. Although the protein phosphatase 2A (PP2A) has been proposed to be both, directly and indirectly, involved in spindle assembly checkpoint inactivation in mammalian cells, whether it is similarly operating in the fission yeast Schizosaccharomycer pombe has never been demonstrated. Here, we investigated whether fission yeast PP2A is involved in SAC silencing by following the rate of cyclin B (Cdc13) destruction at SPBs during the recovery phase in nda3-KM311 cells released from the inhibition of APC/C by the activated spindle checkpoint. The timing of the SAC inactivation is only slightly delayed when two B56 regulatory subunits (Par1 and Par2) of fission yeast PP2A are absent. Overproduction of individual PP2A subunits either globally in the nda3-KM311 arrest-and-release system or locally in the synthetic spindle checkpoint activation system only slightly suppresses the SAC silencing defects in PP1 deletion (dis2Δ) cells. Our study thus demonstrates that the fission yeast PP2A is not a key regulator actively involved in SAC inactivation.
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Affiliation(s)
- Da-Jie Deng
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Xi Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Kai-Ye Yue
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Yamei Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
| | - Quan-Wen Jin
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, China
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15
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Chica N, Portantier M, Nyquist-Andersen M, Espada-Burriel S, Lopez-Aviles S. Uncoupling of Mitosis and Cytokinesis Upon a Prolonged Arrest in Metaphase Is Influenced by Protein Phosphatases and Mitotic Transcription in Fission Yeast. Front Cell Dev Biol 2022; 10:876810. [PMID: 35923846 PMCID: PMC9340479 DOI: 10.3389/fcell.2022.876810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 05/11/2022] [Indexed: 11/22/2022] Open
Abstract
Depletion of the Anaphase-Promoting Complex/Cyclosome (APC/C) activator Cdc20 arrests cells in metaphase with high levels of the mitotic cyclin (Cyclin B) and the Separase inhibitor Securin. In mammalian cells this arrest has been exploited for the treatment of cancer with drugs that engage the spindle assembly checkpoint and, recently, with chemical inhibitors of the APC/C. While most cells arrested in mitosis for prolonged periods undergo apoptosis, others skip cytokinesis and enter G1 with unsegregated chromosomes. This process, known as mitotic slippage, generates aneuploidy and increases genomic instability in the cancer cell. Here, we analyze the behavior of fission yeast cells arrested in mitosis through the transcriptional silencing of the Cdc20 homolog slp1. While depletion of slp1 readily halts cells in metaphase, this arrest is only transient and a majority of cells eventually undergo cytokinesis and show steady mitotic dephosphorylation. Notably, this occurs in the absence of Cyclin B (Cdc13) degradation. We investigate the involvement of phosphatase activity in these events and demonstrate that PP2A-B55Pab1 is required to prevent septation and, during the arrest, its CDK-mediated inhibition facilitates the induction of cytokinesis. In contrast, deletion of PP2A-B56Par1 completely abrogates septation. We show that this effect is partly due to this mutant entering mitosis with reduced CDK activity. Interestingly, both PP2A-B55Pab1 and PP2A-B56Par1, as well as Clp1 (the homolog of the budding yeast mitotic phosphatase Cdc14) are required for the dephosphorylation of mitotic substrates during the escape. Finally, we show that the mitotic transcriptional wave controlled by the RFX transcription factor Sak1 facilitates the induction of cytokinesis and also requires the activity of PP2A-B56Par1 in a mechanism independent of CDK.
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Affiliation(s)
- Nathalia Chica
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL partnership, Faculty of Medicine, University of Oslo, Oslo, Norway
- *Correspondence: Sandra Lopez-Aviles, ; Nathalia Chica,
| | - Marina Portantier
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL partnership, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Mari Nyquist-Andersen
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL partnership, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Silvia Espada-Burriel
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL partnership, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Sandra Lopez-Aviles
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL partnership, Faculty of Medicine, University of Oslo, Oslo, Norway
- Institute of Biosciences (IBV), Faculty of Mathematics and Natural Sciences, University of Oslo, Oslo, Norway
- *Correspondence: Sandra Lopez-Aviles, ; Nathalia Chica,
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16
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Adler SO, Spiesser TW, Uschner F, Münzner U, Hahn J, Krantz M, Klipp E. A yeast cell cycle model integrating stress, signaling, and physiology. FEMS Yeast Res 2022; 22:6592118. [PMID: 35617157 PMCID: PMC9246278 DOI: 10.1093/femsyr/foac026] [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: 01/14/2022] [Revised: 04/22/2022] [Accepted: 05/23/2022] [Indexed: 11/25/2022] Open
Abstract
The cell division cycle in eukaryotic cells is a series of highly coordinated molecular interactions that ensure that cell growth, duplication of genetic material, and actual cell division are precisely orchestrated to give rise to two viable progeny cells. Moreover, the cell cycle machinery is responsible for incorporating information about external cues or internal processes that the cell must keep track of to ensure a coordinated, timely progression of all related processes. This is most pronounced in multicellular organisms, but also a cardinal feature in model organisms such as baker's yeast. The complex and integrative behavior is difficult to grasp and requires mathematical modeling to fully understand the quantitative interplay of the single components within the entire system. Here, we present a self-oscillating mathematical model of the yeast cell cycle that comprises all major cyclins and their main regulators. Furthermore, it accounts for the regulation of the cell cycle machinery by a series of external stimuli such as mating pheromones and changes in osmotic pressure or nutrient quality. We demonstrate how the external perturbations modify the dynamics of cell cycle components and how the cell cycle resumes after adaptation to or relief from stress.
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Affiliation(s)
- Stephan O Adler
- Theoretical Biophysics, Humboldt-Universität zu Berlin, Invalidenstr. 42, 10115 Berlin, Germany
| | - Thomas W Spiesser
- Theoretical Biophysics, Humboldt-Universität zu Berlin, Invalidenstr. 42, 10115 Berlin, Germany
| | - Friedemann Uschner
- Theoretical Biophysics, Humboldt-Universität zu Berlin, Invalidenstr. 42, 10115 Berlin, Germany.,Institute for Medical Informatics and Biometry, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Sachsen, Germany
| | - Ulrike Münzner
- Theoretical Biophysics, Humboldt-Universität zu Berlin, Invalidenstr. 42, 10115 Berlin, Germany.,Laboratory of Cell Systems, Institute for Protein Research, Osaka University, 3-2 Yamadaoka, 565-0871, Suita, Osaka, Japan
| | - Jens Hahn
- Theoretical Biophysics, Humboldt-Universität zu Berlin, Invalidenstr. 42, 10115 Berlin, Germany
| | - Marcus Krantz
- Theoretical Biophysics, Humboldt-Universität zu Berlin, Invalidenstr. 42, 10115 Berlin, Germany
| | - Edda Klipp
- Theoretical Biophysics, Humboldt-Universität zu Berlin, Invalidenstr. 42, 10115 Berlin, Germany
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17
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Moyano-Rodríguez Y, Vaquero D, Vilalta-Castany O, Foltman M, Sanchez-Diaz A, Queralt E. PP2A-Cdc55 phosphatase regulates actomyosin ring contraction and septum formation during cytokinesis. Cell Mol Life Sci 2022; 79:165. [PMID: 35230542 PMCID: PMC8888506 DOI: 10.1007/s00018-022-04209-1] [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: 09/01/2021] [Revised: 02/11/2022] [Accepted: 02/13/2022] [Indexed: 11/03/2022]
Abstract
Eukaryotic cells divide and separate all their components after chromosome segregation by a process called cytokinesis to complete cell division. Cytokinesis is highly regulated by the recruitment of the components to the division site and through post-translational modifications such as phosphorylations. The budding yeast mitotic kinases Cdc28-Clb2, Cdc5, and Dbf2-Mob1 phosphorylate several cytokinetic proteins contributing to the regulation of cytokinesis. The PP2A-Cdc55 phosphatase regulates mitosis counteracting Cdk1- and Cdc5-dependent phosphorylation. This prompted us to propose that PP2A-Cdc55 could also be counteracting the mitotic kinases during cytokinesis. Here we show that in the absence of Cdc55, AMR contraction and the primary septum formation occur asymmetrically to one side of the bud neck supporting a role for PP2A-Cdc55 in cytokinesis regulation. In addition, by in vivo and in vitro assays, we show that PP2A-Cdc55 dephosphorylates the chitin synthase II (Chs2 in budding yeast) a component of the Ingression Progression Complexes (IPCs) involved in cytokinesis. Interestingly, the non-phosphorylable version of Chs2 rescues the asymmetric AMR contraction and the defective septa formation observed in cdc55∆ mutant cells. Therefore, timely dephosphorylation of the Chs2 by PP2A-Cdc55 is crucial for proper actomyosin ring contraction. These findings reveal a new mechanism of cytokinesis regulation by the PP2A-Cdc55 phosphatase and extend our knowledge of the involvement of multiple phosphatases during cytokinesis.
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Affiliation(s)
- Yolanda Moyano-Rodríguez
- Cell Cycle Group, Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), Av. Gran Via de L'Hospitalet 199-203, L'Hospitalet de Llobregat, Barcelona, Spain
| | - David Vaquero
- Cell Cycle Group, Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), Av. Gran Via de L'Hospitalet 199-203, L'Hospitalet de Llobregat, Barcelona, Spain.,Instituto de Biomedicina de Valencia (IBV-CSIC), C/ Jaume Roig 11, Valencia, Spain
| | - Odena Vilalta-Castany
- Cell Cycle Group, Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), Av. Gran Via de L'Hospitalet 199-203, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Magdalena Foltman
- Instituto de Biomedicina y Biotecnología de Cantabria, Universidad de Cantabria, CSIC, Santander, Spain.,Departamento de Biología Molecular, Facultad de Medicina, Universidad de Cantabria, Santander, Spain
| | - Alberto Sanchez-Diaz
- Instituto de Biomedicina y Biotecnología de Cantabria, Universidad de Cantabria, CSIC, Santander, Spain.,Departamento de Biología Molecular, Facultad de Medicina, Universidad de Cantabria, Santander, Spain
| | - Ethel Queralt
- Cell Cycle Group, Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), Av. Gran Via de L'Hospitalet 199-203, L'Hospitalet de Llobregat, Barcelona, Spain. .,Instituto de Biomedicina de Valencia (IBV-CSIC), C/ Jaume Roig 11, Valencia, Spain.
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18
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Philip J, Örd M, Silva A, Singh S, Diffley JFX, Remus D, Loog M, Ikui AE. Cdc6 is sequentially regulated by PP2A-Cdc55, Cdc14, and Sic1 for origin licensing in S. cerevisiae. eLife 2022; 11:e74437. [PMID: 35142288 PMCID: PMC8830886 DOI: 10.7554/elife.74437] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 12/15/2021] [Indexed: 01/31/2023] Open
Abstract
Cdc6, a subunit of the pre-replicative complex (pre-RC), contains multiple regulatory cyclin-dependent kinase (Cdk1) consensus sites, SP or TP motifs. In Saccharomyces cerevisiae, Cdk1 phosphorylates Cdc6-T7 to recruit Cks1, the Cdk1 phospho-adaptor in S phase, for subsequent multisite phosphorylation and protein degradation. Cdc6 accumulates in mitosis and is tightly bound by Clb2 through N-terminal phosphorylation in order to prevent premature origin licensing and degradation. It has been extensively studied how Cdc6 phosphorylation is regulated by the cyclin-Cdk1 complex. However, a detailed mechanism on how Cdc6 phosphorylation is reversed by phosphatases has not been elucidated. Here, we show that PP2ACdc55 dephosphorylates Cdc6 N-terminal sites to release Clb2. Cdc14 dephosphorylates the C-terminal phospho-degron, leading to Cdc6 stabilization in mitosis. In addition, Cdk1 inhibitor Sic1 releases Clb2·Cdk1·Cks1 from Cdc6 to load Mcm2-7 on the chromatin upon mitotic exit. Thus, pre-RC assembly and origin licensing are promoted by phosphatases through the attenuation of distinct Cdk1-dependent Cdc6 inhibitory mechanisms.
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Affiliation(s)
- Jasmin Philip
- The PhD Program in Biochemistry, The Graduate Center, CUNYBrooklynUnited States
- Brooklyn CollegeBrooklynUnited States
| | | | - Andriele Silva
- The PhD Program in Biochemistry, The Graduate Center, CUNYBrooklynUnited States
- Brooklyn CollegeBrooklynUnited States
| | - Shaneen Singh
- The PhD Program in Biochemistry, The Graduate Center, CUNYBrooklynUnited States
- Brooklyn CollegeBrooklynUnited States
| | | | - Dirk Remus
- Memorial Sloan-Kettering Cancer CenterNew YorkUnited States
| | | | - Amy E Ikui
- The PhD Program in Biochemistry, The Graduate Center, CUNYBrooklynUnited States
- Brooklyn CollegeBrooklynUnited States
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19
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The CWI Pathway: A Versatile Toolbox to Arrest Cell-Cycle Progression. J Fungi (Basel) 2021; 7:jof7121041. [PMID: 34947023 PMCID: PMC8704918 DOI: 10.3390/jof7121041] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 11/29/2021] [Accepted: 12/02/2021] [Indexed: 02/02/2023] Open
Abstract
Cell-signaling pathways are essential for cells to respond and adapt to changes in their environmental conditions. The cell-wall integrity (CWI) pathway of Saccharomyces cerevisiae is activated by environmental stresses, compounds, and morphogenetic processes that compromise the cell wall, orchestrating the appropriate cellular response to cope with these adverse conditions. During cell-cycle progression, the CWI pathway is activated in periods of polarized growth, such as budding or cytokinesis, regulating cell-wall biosynthesis and the actin cytoskeleton. Importantly, accumulated evidence has indicated a reciprocal regulation of the cell-cycle regulatory system by the CWI pathway. In this paper, we describe how the CWI pathway regulates the main cell-cycle transitions in response to cell-surface perturbance to delay cell-cycle progression. In particular, it affects the Start transcriptional program and the initiation of DNA replication at the G1/S transition, and entry and progression through mitosis. We also describe the involvement of the CWI pathway in the response to genotoxic stress and its connection with the DNA integrity checkpoint, the mechanism that ensures the correct transmission of genetic material and cell survival. Thus, the CWI pathway emerges as a master brake that stops cell-cycle progression when cells are coping with distinct unfavorable conditions.
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20
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Haluska C, Jin F, Wang Y. Protein phosphatase 2A (PP2A) promotes anaphase entry after DNA replication stress in budding yeast. Mol Biol Cell 2021; 32:ar36. [PMID: 34668760 PMCID: PMC8694091 DOI: 10.1091/mbc.e21-04-0222] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 10/01/2021] [Accepted: 10/05/2021] [Indexed: 12/31/2022] Open
Abstract
DNA replication stress activates the S-phase checkpoint that arrests the cell cycle, but it is poorly understood how cells recover from this arrest. Cyclin-dependent kinase (CDK) and protein phosphatase 2A (PP2A) are key cell cycle regulators, and Cdc55 is a regulatory subunit of PP2A in budding yeast. We found that yeast cells lacking functional PP2ACdc55 showed slow growth in the presence of hydroxyurea (HU), a DNA synthesis inhibitor, without obvious viability loss. Moreover, PP2A mutants exhibited delayed anaphase entry and sustained levels of anaphase inhibitor Pds1 after HU treatment. A DNA damage checkpoint Chk1 phosphorylates and stabilizes Pds1. We show that chk1Δ and mutation of the Chk1 phosphorylation sites in Pds1 largely restored efficient anaphase entry in PP2A mutants after HU treatment. In addition, deletion of SWE1, which encodes the inhibitory kinase for CDK or mutation of the Swe1 phosphorylation site in CDK (cdc28F19), also suppressed the anaphase entry delay in PP2A mutants after HU treatment. Our genetic data suggest that Swe1/CDK acts upstream of Pds1. Surprisingly, cdc55Δ showed significant suppression to the viability loss of S-phase checkpoint mutants during DNA synthesis block. Together, our results uncover a PP2A-Swe1-CDK-Chk1-Pds1 axis that promotes recovery from DNA replication stress.
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Affiliation(s)
- Cory Haluska
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306-4300
| | - Fengzhi Jin
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306-4300
| | - Yanchang Wang
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306-4300
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21
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Hollenstein DM, Gérecová G, Romanov N, Ferrari J, Veis J, Janschitz M, Beyer R, Schüller C, Ogris E, Hartl M, Ammerer G, Reiter W. A phosphatase-centric mechanism drives stress signaling response. EMBO Rep 2021; 22:e52476. [PMID: 34558777 PMCID: PMC8567219 DOI: 10.15252/embr.202152476] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 08/27/2021] [Accepted: 09/03/2021] [Indexed: 12/14/2022] Open
Abstract
Changing environmental cues lead to the adjustment of cellular physiology by phosphorylation signaling networks that typically center around kinases as active effectors and phosphatases as antagonistic elements. Here, we report a signaling mechanism that reverses this principle. Using the hyperosmotic stress response in Saccharomyces cerevisiae as a model system, we find that a phosphatase-driven mechanism causes induction of phosphorylation. The key activating step that triggers this phospho-proteomic response is the Endosulfine-mediated inhibition of protein phosphatase 2A-Cdc55 (PP2ACdc55 ), while we do not observe concurrent kinase activation. In fact, many of the stress-induced phosphorylation sites appear to be direct substrates of the phosphatase, rendering PP2ACdc55 the main downstream effector of a signaling response that operates in parallel and independent of the well-established kinase-centric stress signaling pathways. This response affects multiple cellular processes and is required for stress survival. Our results demonstrate how a phosphatase can assume the role of active downstream effectors during signaling and allow re-evaluating the impact of phosphatases on shaping the phosphorylome.
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Affiliation(s)
- David Maria Hollenstein
- Department of Biochemistry and Cell BiologyMax Perutz LabsVienna BioCenter (VBC)University of ViennaViennaAustria
| | - Gabriela Gérecová
- Department of Biochemistry and Cell BiologyMax Perutz LabsVienna BioCenter (VBC)University of ViennaViennaAustria
| | | | - Jessica Ferrari
- Department of Biochemistry and Cell BiologyMax Perutz LabsVienna BioCenter (VBC)University of ViennaViennaAustria
| | - Jiri Veis
- Department of Biochemistry and Cell BiologyMax Perutz LabsVienna BioCenter (VBC)University of ViennaViennaAustria
- Center for Medical BiochemistryMax Perutz Labs, Vienna BioCenterMedical University of ViennaViennaAustria
| | - Marion Janschitz
- Department of Biochemistry and Cell BiologyMax Perutz LabsVienna BioCenter (VBC)University of ViennaViennaAustria
| | - Reinhard Beyer
- Department of Applied Genetics and Cell Biology (DAGZ)University of Natural Resources and Life Sciences (BOKU)ViennaAustria
- Research Platform Bioactive Microbial Metabolites (BiMM)Tulln a.d. DonauAustria
| | - Christoph Schüller
- Department of Applied Genetics and Cell Biology (DAGZ)University of Natural Resources and Life Sciences (BOKU)ViennaAustria
- Research Platform Bioactive Microbial Metabolites (BiMM)Tulln a.d. DonauAustria
| | - Egon Ogris
- Center for Medical BiochemistryMax Perutz Labs, Vienna BioCenterMedical University of ViennaViennaAustria
| | - Markus Hartl
- Department of Biochemistry and Cell BiologyMax Perutz LabsVienna BioCenter (VBC)University of ViennaViennaAustria
- Mass Spectrometry FacilityMax Perutz Labs, Vienna BioCenterUniversity of ViennaViennaAustria
| | - Gustav Ammerer
- Department of Biochemistry and Cell BiologyMax Perutz LabsVienna BioCenter (VBC)University of ViennaViennaAustria
| | - Wolfgang Reiter
- Department of Biochemistry and Cell BiologyMax Perutz LabsVienna BioCenter (VBC)University of ViennaViennaAustria
- Mass Spectrometry FacilityMax Perutz Labs, Vienna BioCenterUniversity of ViennaViennaAustria
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22
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Alonso-Ramos P, Álvarez-Melo D, Strouhalova K, Pascual-Silva C, Garside GB, Arter M, Bermejo T, Grigaitis R, Wettstein R, Fernández-Díaz M, Matos J, Geymonat M, San-Segundo PA, Carballo JA. The Cdc14 Phosphatase Controls Resolution of Recombination Intermediates and Crossover Formation during Meiosis. Int J Mol Sci 2021; 22:ijms22189811. [PMID: 34575966 PMCID: PMC8470964 DOI: 10.3390/ijms22189811] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 09/06/2021] [Accepted: 09/08/2021] [Indexed: 12/15/2022] Open
Abstract
Meiotic defects derived from incorrect DNA repair during gametogenesis can lead to mutations, aneuploidies and infertility. The coordinated resolution of meiotic recombination intermediates is required for crossover formation, ultimately necessary for the accurate completion of both rounds of chromosome segregation. Numerous master kinases orchestrate the correct assembly and activity of the repair machinery. Although much less is known, the reversal of phosphorylation events in meiosis must also be key to coordinate the timing and functionality of repair enzymes. Cdc14 is a crucial phosphatase required for the dephosphorylation of multiple CDK1 targets in many eukaryotes. Mutations that inactivate this phosphatase lead to meiotic failure, but until now it was unknown if Cdc14 plays a direct role in meiotic recombination. Here, we show that the elimination of Cdc14 leads to severe defects in the processing and resolution of recombination intermediates, causing a drastic depletion in crossovers when other repair pathways are compromised. We also show that Cdc14 is required for the correct activity and localization of the Holliday Junction resolvase Yen1/GEN1. We reveal that Cdc14 regulates Yen1 activity from meiosis I onwards, and this function is essential for crossover resolution in the absence of other repair pathways. We also demonstrate that Cdc14 and Yen1 are required to safeguard sister chromatid segregation during the second meiotic division, a late action that is independent of the earlier role in crossover formation. Thus, this work uncovers previously undescribed functions of the evolutionary conserved Cdc14 phosphatase in the regulation of meiotic recombination.
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Affiliation(s)
- Paula Alonso-Ramos
- Center for Biological Research Margarita Salas, Department of Cellular and Molecular Biology, Spanish National Research Council (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain; (P.A.-R.); (D.Á.-M.); (K.S.); (C.P.-S.); (T.B.); (M.F.-D.)
| | - David Álvarez-Melo
- Center for Biological Research Margarita Salas, Department of Cellular and Molecular Biology, Spanish National Research Council (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain; (P.A.-R.); (D.Á.-M.); (K.S.); (C.P.-S.); (T.B.); (M.F.-D.)
| | - Katerina Strouhalova
- Center for Biological Research Margarita Salas, Department of Cellular and Molecular Biology, Spanish National Research Council (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain; (P.A.-R.); (D.Á.-M.); (K.S.); (C.P.-S.); (T.B.); (M.F.-D.)
- Department of Cell Biology, Charles University, Viničná 7, 12843 Prague, Czech Republic
| | - Carolina Pascual-Silva
- Center for Biological Research Margarita Salas, Department of Cellular and Molecular Biology, Spanish National Research Council (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain; (P.A.-R.); (D.Á.-M.); (K.S.); (C.P.-S.); (T.B.); (M.F.-D.)
| | - George B. Garside
- Genome Damage and Stability Centre, University of Sussex, Brighton BN1 4DY, UK;
- Leibniz Institute for Age Research/Fritz Lipmann Institute (FLI), Beutenbergstr. 11, D-07745 Jena, Germany
| | - Meret Arter
- Institute of Biochemistry, HPM D6.5-ETH Zürich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland; (M.A.); (R.G.); (R.W.); (J.M.)
- Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Teresa Bermejo
- Center for Biological Research Margarita Salas, Department of Cellular and Molecular Biology, Spanish National Research Council (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain; (P.A.-R.); (D.Á.-M.); (K.S.); (C.P.-S.); (T.B.); (M.F.-D.)
| | - Rokas Grigaitis
- Institute of Biochemistry, HPM D6.5-ETH Zürich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland; (M.A.); (R.G.); (R.W.); (J.M.)
- Max Perutz Labs, University of Vienna, Dr. Bohr-Gasse 9, 1030 Vienna, Austria
| | - Rahel Wettstein
- Institute of Biochemistry, HPM D6.5-ETH Zürich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland; (M.A.); (R.G.); (R.W.); (J.M.)
- Max Perutz Labs, University of Vienna, Dr. Bohr-Gasse 9, 1030 Vienna, Austria
| | - Marta Fernández-Díaz
- Center for Biological Research Margarita Salas, Department of Cellular and Molecular Biology, Spanish National Research Council (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain; (P.A.-R.); (D.Á.-M.); (K.S.); (C.P.-S.); (T.B.); (M.F.-D.)
| | - Joao Matos
- Institute of Biochemistry, HPM D6.5-ETH Zürich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland; (M.A.); (R.G.); (R.W.); (J.M.)
- Max Perutz Labs, University of Vienna, Dr. Bohr-Gasse 9, 1030 Vienna, Austria
| | - Marco Geymonat
- Department of Genetics, University of Cambridge, Downing Street, Cambridge CB2 3EH, UK;
| | - Pedro A. San-Segundo
- Institute of Functional Biology and Genomics (IBFG), Spanish National Research Council (CSIC) and University of Salamanca, 37007 Salamanca, Spain;
| | - Jesús A. Carballo
- Center for Biological Research Margarita Salas, Department of Cellular and Molecular Biology, Spanish National Research Council (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain; (P.A.-R.); (D.Á.-M.); (K.S.); (C.P.-S.); (T.B.); (M.F.-D.)
- Correspondence:
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23
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Pirincci Ercan D, Chrétien F, Chakravarty P, Flynn HR, Snijders AP, Uhlmann F. Budding yeast relies on G 1 cyclin specificity to couple cell cycle progression with morphogenetic development. SCIENCE ADVANCES 2021; 7:eabg0007. [PMID: 34088668 PMCID: PMC8177710 DOI: 10.1126/sciadv.abg0007] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 04/19/2021] [Indexed: 05/04/2023]
Abstract
Two models have been put forward for cyclin-dependent kinase (Cdk) control of the cell cycle. In the qualitative model, cell cycle events are ordered by distinct substrate specificities of successive cyclin waves. Alternatively, in the quantitative model, the gradual rise of Cdk activity from G1 phase to mitosis leads to ordered substrate phosphorylation at sequential thresholds. Here, we study the relative contributions of qualitative and quantitative Cdk control in Saccharomyces cerevisiae All S phase and mitotic cyclins can be replaced by a single mitotic cyclin, albeit at the cost of reduced fitness. A single cyclin can also replace all G1 cyclins to support ordered cell cycle progression, fulfilling key predictions of the quantitative model. However, single-cyclin cells fail to polarize or grow buds and thus cannot survive. Our results suggest that budding yeast has become dependent on G1 cyclin specificity to couple cell cycle progression to essential morphogenetic events.
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Affiliation(s)
| | - Florine Chrétien
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, UK
| | - Probir Chakravarty
- Bioinformatics and Biostatistics Science Technology Platform, The Francis Crick Institute, London, UK
| | - Helen R Flynn
- Proteomics Science Technology Platform, The Francis Crick Institute, London, UK
| | | | - Frank Uhlmann
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, UK.
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24
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Zhou X, Li W, Liu Y, Amon A. Cross-compartment signal propagation in the mitotic exit network. eLife 2021; 10:e63645. [PMID: 33481703 PMCID: PMC7822594 DOI: 10.7554/elife.63645] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 01/06/2021] [Indexed: 12/26/2022] Open
Abstract
In budding yeast, the mitotic exit network (MEN), a GTPase signaling cascade, integrates spatial and temporal cues to promote exit from mitosis. This signal integration requires transmission of a signal generated on the cytoplasmic face of spindle pole bodies (SPBs; yeast equivalent of centrosomes) to the nucleolus, where the MEN effector protein Cdc14 resides. Here, we show that the MEN activating signal at SPBs is relayed to Cdc14 in the nucleolus through the dynamic localization of its terminal kinase complex Dbf2-Mob1. Cdc15, the protein kinase that activates Dbf2-Mob1 at SPBs, also regulates its nuclear access. Once in the nucleus, priming phosphorylation of Cfi1/Net1, the nucleolar anchor of Cdc14, by the Polo-like kinase Cdc5 targets Dbf2-Mob1 to the nucleolus. Nucleolar Dbf2-Mob1 then phosphorylates Cfi1/Net1 and Cdc14, activating Cdc14. The kinase-primed transmission of the MEN signal from the cytoplasm to the nucleolus exemplifies how signaling cascades can bridge distant inputs and responses.
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Affiliation(s)
- Xiaoxue Zhou
- David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Wenxue Li
- Yale Cancer Biology Institute, Department of Pharmacology, Yale UniversityWest HavenUnited States
| | - Yansheng Liu
- Yale Cancer Biology Institute, Department of Pharmacology, Yale UniversityWest HavenUnited States
| | - Angelika Amon
- David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of TechnologyCambridgeUnited States
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25
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Abstract
Separase is a large cysteine protease in eukaryotes and has crucial roles in many cellular processes, especially chromosome segregation during mitosis and meiosis, apoptosis, DNA damage repair, centrosome disengagement and duplication, spindle stabilization and elongation. It dissolves the cohesion between sister chromatids by cleaving one of the subunits of the cohesin ring for chromosome segregation. The activity of separase is tightly controlled at many levels, through direct binding of inhibitory proteins as well as posttranslational modification. Dysregulation of separase activity is linked to cancer and genome instability, making it a target for drug discovery. One of the best-known inhibitors of separase is securin, which has been identified in yeast, plants, and animals. Securin forms a tight complex with separase and potently inhibits its catalytic activity. Recent structures of the separase-securin complex have revealed the molecular mechanism for the inhibitory activity of securin. A segment of securin is bound in the active site of separase, thereby blocking substrate binding. Securin itself is not cleaved by separase as its binding mode is not compatible with catalysis. Securin also has extensive interactions with separase outside the active site, consistent with its function as a chaperone to stabilize this enzyme.
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Affiliation(s)
- Shukun Luo
- Department of Biological Sciences, Columbia University, New York, NY, 10027, USA
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Liang Tong
- Department of Biological Sciences, Columbia University, New York, NY, 10027, USA.
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26
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Howell RSM, Klemm C, Thorpe PH, Csikász-Nagy A. Unifying the mechanism of mitotic exit control in a spatiotemporal logical model. PLoS Biol 2020; 18:e3000917. [PMID: 33180788 PMCID: PMC7685450 DOI: 10.1371/journal.pbio.3000917] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 11/24/2020] [Accepted: 10/09/2020] [Indexed: 11/18/2022] Open
Abstract
The transition from mitosis into the first gap phase of the cell cycle in budding yeast is controlled by the Mitotic Exit Network (MEN). The network interprets spatiotemporal cues about the progression of mitosis and ensures that release of Cdc14 phosphatase occurs only after completion of key mitotic events. The MEN has been studied intensively; however, a unified understanding of how localisation and protein activity function together as a system is lacking. In this paper, we present a compartmental, logical model of the MEN that is capable of representing spatial aspects of regulation in parallel to control of enzymatic activity. We show that our model is capable of correctly predicting the phenotype of the majority of mutants we tested, including mutants that cause proteins to mislocalise. We use a continuous time implementation of the model to demonstrate that Cdc14 Early Anaphase Release (FEAR) ensures robust timing of anaphase, and we verify our findings in living cells. Furthermore, we show that our model can represent measured cell-cell variation in Spindle Position Checkpoint (SPoC) mutants. This work suggests a general approach to incorporate spatial effects into logical models. We anticipate that the model itself will be an important resource to experimental researchers, providing a rigorous platform to test hypotheses about regulation of mitotic exit.
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Affiliation(s)
- Rowan S M Howell
- The Francis Crick Institute, London, United Kingdom.,Randall Centre for Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Cinzia Klemm
- School of Biological and Chemical Sciences, Queen Mary University, London, United Kingdom
| | - Peter H Thorpe
- School of Biological and Chemical Sciences, Queen Mary University, London, United Kingdom
| | - Attila Csikász-Nagy
- Randall Centre for Cell and Molecular Biophysics, King's College London, London, United Kingdom.,Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Budapest, Hungary
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27
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Hao J, Ci X, Wang Y, Choi SYC, Sullivan SE, Xue H, Wu R, Dong X, Haegert AM, Collins CC, Lin D, Wang Y. GRB10 sustains AR activity by interacting with PP2A in prostate cancer cells. Int J Cancer 2020; 148:469-480. [PMID: 33038264 DOI: 10.1002/ijc.33335] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 09/06/2020] [Accepted: 09/30/2020] [Indexed: 01/22/2023]
Abstract
Prostate cancer (PCa) progression is driven by androgen receptor (AR) signaling. Unfortunately, androgen-deprivation therapy and the use of even more potent AR pathway inhibitors (ARPIs) cannot bring about a cure. ARPI resistance (ie, castration-resistant PCa, CRPC) will inevitably develop. Previously, we demonstrated that GRB10 is an AR transcriptionally repressed gene that functionally contributes to CRPC development and ARPI resistance. GRB10 expression is elevated prior to CRPC development in our patient-derived xenograft models and is significantly upregulated in clinical CRPC samples. Here, we analyzed transcriptomic data from GRB10 knockdown in PCa cells and found that AR signaling is downregulated. While the mRNA expression of AR target genes decreased upon GRB10 knockdown, AR expression was not affected at the mRNA or protein level. We further found that phosphorylation of AR serine 81 (S81), which is critical for AR transcriptional activity, is decreased by GRB10 knockdown and increased by its overexpression. Luciferase assay using GRB10-knockdown cells also indicate reduced AR activity. Immunoprecipitation coupled with mass spectrometry revealed an interaction between GRB10 and the PP2A complex, which is a known phosphatase of AR. Further validations and analyses showed that GRB10 binds to the PP2Ac catalytic subunit with its PH domain. Mechanistically, GRB10 knockdown increased PP2Ac protein stability, which in turn decreased AR S81 phosphorylation and reduced AR activity. Our findings indicate a reciprocal feedback between GRB10 and AR signaling, implying the importance of GRB10 in PCa progression.
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Affiliation(s)
- Jun Hao
- Vancouver Prostate Centre, Department of Urologic Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Experimental Therapeutics, BC Cancer Agency, Vancouver, British Columbia, Canada
| | - Xinpei Ci
- Vancouver Prostate Centre, Department of Urologic Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Experimental Therapeutics, BC Cancer Agency, Vancouver, British Columbia, Canada
| | - Yong Wang
- Vancouver Prostate Centre, Department of Urologic Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Urology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Stephen Yiu Chuen Choi
- Vancouver Prostate Centre, Department of Urologic Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Experimental Therapeutics, BC Cancer Agency, Vancouver, British Columbia, Canada
| | - Sarah E Sullivan
- Vancouver Prostate Centre, Department of Urologic Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Kinesiology and Physical Education, McGill University, Quebec, Canada
| | - Hui Xue
- Department of Experimental Therapeutics, BC Cancer Agency, Vancouver, British Columbia, Canada
| | - Rebecca Wu
- Department of Experimental Therapeutics, BC Cancer Agency, Vancouver, British Columbia, Canada
| | - Xin Dong
- Department of Experimental Therapeutics, BC Cancer Agency, Vancouver, British Columbia, Canada
| | - Anne M Haegert
- Vancouver Prostate Centre, Department of Urologic Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Colin C Collins
- Vancouver Prostate Centre, Department of Urologic Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Dong Lin
- Vancouver Prostate Centre, Department of Urologic Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Experimental Therapeutics, BC Cancer Agency, Vancouver, British Columbia, Canada
| | - Yuzhuo Wang
- Vancouver Prostate Centre, Department of Urologic Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Experimental Therapeutics, BC Cancer Agency, Vancouver, British Columbia, Canada
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28
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Plank M, Berti M, Loewith R. Phosphoproteomic Effects of Acute Depletion of PP2A Regulatory Subunit Cdc55. Proteomics 2020; 21:e2000166. [PMID: 32970932 DOI: 10.1002/pmic.202000166] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 09/15/2020] [Indexed: 11/08/2022]
Abstract
Protein phosphatase regulatory subunits are increasingly recognized as promising drug targets. In the absence of an existing drug, inducible degradation provides a means of predicting candidate targets. Here auxin-inducible degradation of Saccharomyces cerevisiae PP2A regulatory subunit Cdc55 in combination with quantitative phosphoproteomics is employed. A prevalence of hyperphosphorylated phosphopeptides indicates that the approach successfully identified direct PP2ACdc55 targets. PRM follow up of data-dependent acquisition results confirmed that vacuolar amino acid transporters are among the proteins most strongly affected by Cdc55 depletion.
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Affiliation(s)
- Michael Plank
- Department of Molecular Biology, University of Geneva, Geneva, CH-1211, Switzerland.,National Centre of Competence in Research-Chemical Biology, University of Geneva, Geneva, CH-1211, Switzerland
| | - Marina Berti
- Department of Molecular Biology, University of Geneva, Geneva, CH-1211, Switzerland
| | - Robbie Loewith
- Department of Molecular Biology, University of Geneva, Geneva, CH-1211, Switzerland.,National Centre of Competence in Research-Chemical Biology, University of Geneva, Geneva, CH-1211, Switzerland
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29
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Touati SA, Hofbauer L, Jones AW, Snijders AP, Kelly G, Uhlmann F. Cdc14 and PP2A Phosphatases Cooperate to Shape Phosphoproteome Dynamics during Mitotic Exit. Cell Rep 2020; 29:2105-2119.e4. [PMID: 31722221 PMCID: PMC6857435 DOI: 10.1016/j.celrep.2019.10.041] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 09/27/2019] [Accepted: 10/10/2019] [Indexed: 12/22/2022] Open
Abstract
Temporal control over protein phosphorylation and dephosphorylation is crucial for accurate chromosome segregation and for completion of the cell division cycle during exit from mitosis. In budding yeast, the Cdc14 phosphatase is thought to be a major regulator at this time, while in higher eukaryotes PP2A phosphatases take a dominant role. Here, we use time-resolved phosphoproteome analysis in budding yeast to evaluate the respective contributions of Cdc14, PP2ACdc55, and PP2ARts1. This reveals an overlapping requirement for all three phosphatases during mitotic progression. Our time-resolved phosphoproteome resource reveals how Cdc14 instructs the sequential pattern of phosphorylation changes, in part through preferential recognition of serine-based cyclin-dependent kinase (Cdk) substrates. PP2ACdc55 and PP2ARts1 in turn exhibit a broad substrate spectrum with some selectivity for phosphothreonines and a role for PP2ARts1 in sustaining Aurora kinase activity. These results illustrate synergy and coordination between phosphatases as they orchestrate phosphoproteome dynamics during mitotic progression. Cdc14, PP2ACdc55, and PP2ARts1 phosphatases cooperate during budding yeast mitosis Cdc14 targets serine Cdk motifs for rapid dephosphorylation PP2ACdc55 dephosphorylates Cdk and Plk substrates on threonine residues PP2ARts1 displays regulatory crosstalk with Aurora kinase
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Affiliation(s)
- Sandra A Touati
- Chromosome Segregation Laboratory, The Francis Crick Institute, London NW1 1AT, UK.
| | - Lorena Hofbauer
- Chromosome Segregation Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Andrew W Jones
- Mass Spectrometry Proteomics Science Technology Platform, The Francis Crick Institute, London NW1 1AT, UK
| | - Ambrosius P Snijders
- Mass Spectrometry Proteomics Science Technology Platform, The Francis Crick Institute, London NW1 1AT, UK
| | - Gavin Kelly
- Bioinformatics & Biostatistics Science Technology Platform, The Francis Crick Institute, London NW1 1AT, UK
| | - Frank Uhlmann
- Chromosome Segregation Laboratory, The Francis Crick Institute, London NW1 1AT, UK.
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30
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Jiménez J, Queralt E, Posas F, de Nadal E. The regulation of Net1/Cdc14 by the Hog1 MAPK upon osmostress unravels a new mechanism regulating mitosis. Cell Cycle 2020; 19:2105-2118. [PMID: 32794416 PMCID: PMC7513861 DOI: 10.1080/15384101.2020.1804222] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
During evolution, cells have developed a plethora of mechanisms to optimize survival in a changing and unpredictable environment. In this regard, they have evolved networks that include environmental sensors, signaling transduction molecules and response mechanisms. Hog1 (yeast) and p38 (mammals) stress-activated protein kinases (SAPKs) are activated upon stress and they drive a full collection of cell adaptive responses aimed to maximize survival. SAPKs are extensively used to learn about the mechanisms through which cells adapt to changing environments. In addition to regulating gene expression and metabolism, SAPKs control cell cycle progression. In this review, we will discuss the latest findings related to the SAPK-driven regulation of mitosis upon osmostress in yeast.
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Affiliation(s)
- Javier Jiménez
- Departament De Ciències Experimentals I De La Salut, Universitat Pompeu Fabra (UPF) , Barcelona, Spain.,Department of Ciències Bàsiques, Facultat De Medicina I Ciències De La Salut, Universitat Internacional De Catalunya , Barcelona, Spain
| | - Ethel Queralt
- Cell Cycle Group, Institut d'Investigacions Biomèdica De Bellvitge (IDIBELL), L'Hospitalet De Llobregat , Barcelona, Spain
| | - Francesc Posas
- Departament De Ciències Experimentals I De La Salut, Universitat Pompeu Fabra (UPF) , Barcelona, Spain.,Institute for Research in Biomedicine (IRB Barcelona), the Barcelona Institute of Science and Technology , 08028 Barcelona, Spain
| | - Eulàlia de Nadal
- Departament De Ciències Experimentals I De La Salut, Universitat Pompeu Fabra (UPF) , Barcelona, Spain.,Institute for Research in Biomedicine (IRB Barcelona), the Barcelona Institute of Science and Technology , 08028 Barcelona, Spain
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31
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Khondker S, Kajjo S, Chandler-Brown D, Skotheim J, Rudner A, Ikui AE. PP2A Cdc55 dephosphorylates Pds1 and inhibits spindle elongation in S. cerevisiae. J Cell Sci 2020; 133:jcs243766. [PMID: 32591482 PMCID: PMC7406319 DOI: 10.1242/jcs.243766] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 06/11/2020] [Indexed: 11/20/2022] Open
Abstract
PP2ACdc55 (the form of protein phosphatase 2A containing Cdc55) regulates cell cycle progression by reversing cyclin-dependent kinase (CDK)- and polo-like kinase (Cdc5)-dependent phosphorylation events. In S. cerevisiae, Cdk1 phosphorylates securin (Pds1), which facilitates Pds1 binding and inhibits separase (Esp1). During anaphase, Esp1 cleaves the cohesin subunit Scc1 and promotes spindle elongation. Here, we show that PP2ACdc55 directly dephosphorylates Pds1 both in vivo and in vitro Pds1 hyperphosphorylation in a cdc55 deletion mutant enhanced the Pds1-Esp1 interaction, which played a positive role in Pds1 nuclear accumulation and in spindle elongation. We also show that nuclear PP2ACdc55 plays a role during replication stress to inhibit spindle elongation. This pathway acted independently of the known Mec1, Swe1 or spindle assembly checkpoint (SAC) checkpoint pathways. We propose a model where Pds1 dephosphorylation by PP2ACdc55 disrupts the Pds1-Esp1 protein interaction and inhibits Pds1 nuclear accumulation, which prevents spindle elongation, a process that is elevated during replication stress.
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Affiliation(s)
- Shoily Khondker
- Biology Department, Brooklyn College, The City University of New York, Brooklyn, NY 11238, USA
- Biology Program, CUNY Graduate Center, New York, NY 10016, USA
| | - Sam Kajjo
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, K1N 6N5, Canada
| | | | - Jan Skotheim
- Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Adam Rudner
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, K1N 6N5, Canada
| | - Amy E. Ikui
- Biology Department, Brooklyn College, The City University of New York, Brooklyn, NY 11238, USA
- Biology Program, CUNY Graduate Center, New York, NY 10016, USA
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32
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Yeast Sphingolipid Phospholipase Gene ISC1 Regulates the Spindle Checkpoint by a CDC55-Dependent Mechanism. Mol Cell Biol 2020; 40:MCB.00340-19. [PMID: 32205408 DOI: 10.1128/mcb.00340-19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 03/18/2020] [Indexed: 01/10/2023] Open
Abstract
Defects in the spindle assembly checkpoint (SAC) can lead to aneuploidy and cancer. Sphingolipids have important roles in many cellular functions, including cell cycle regulation and apoptosis. However, the specific mechanisms and functions of sphingolipids in cell cycle regulation have not been elucidated. Using analysis of concordance for synthetic lethality for the yeast sphingolipid phospholipase ISC1, we identified two groups of genes. The first comprises genes involved in chromosome segregation and stability (CSM3, CTF4, YKE2, DCC1, and GIM4) as synthetically lethal with ISC1 The second group, to which ISC1 belongs, comprises genes involved in the spindle checkpoint (BUB1, MAD1, BIM1, and KAR3), and they all share the same synthetic lethality with the first group. We demonstrate that spindle checkpoint genes act upstream of Isc1, and their deletion phenocopies that of ISC1 Reciprocally, ISC1 deletion mutants were sensitive to benomyl, indicating a SAC defect. Similar to BUB1 deletion, ISC1 deletion prevents spindle elongation in hydroxyurea-treated cells. Mechanistically, PP2A-Cdc55 ceramide-activated phosphatase was found to act downstream of Isc1, thus coupling the spindle checkpoint genes and Isc1 to CDC55-mediated nuclear functions.
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33
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Machín F, Ayra-Plasencia J. Are Anaphase Events Really Irreversible? The Endmost Stages of Cell Division and the Paradox of the DNA Double-Strand Break Repair. Bioessays 2020; 42:e2000021. [PMID: 32363600 DOI: 10.1002/bies.202000021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 03/16/2020] [Indexed: 12/25/2022]
Abstract
It has been recently demonstrated that yeast cells are able to partially regress chromosome segregation in telophase as a response to DNA double-strand breaks (DSBs), likely to find a donor sequence for homology-directed repair (HDR). This regression challenges the traditional concept that establishes anaphase events as irreversible, hence opening a new field of research in cell biology. Here, the nature of this new behavior in yeast is summarized and the underlying mechanisms are speculated about. It is also discussed whether it can be reproduced in other eukaryotes. Overall, this work brings forwards the need of understanding how cells attempt to repair DSBs when transiting the latest stages of mitosis, i.e., anaphase and telophase.
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Affiliation(s)
- Félix Machín
- Unidad de Investigación, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, 38010, Spain.,Instituto de Tecnologías Biomédicas, Universidad de La Laguna, Santa Cruz de Tenerife, 38200, Spain.,Universidad Fernando Pessoa Canarias, Las Palmas de Gran Canaria, 35450, Spain
| | - Jessel Ayra-Plasencia
- Unidad de Investigación, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, 38010, Spain.,Instituto de Tecnologías Biomédicas, Universidad de La Laguna, Santa Cruz de Tenerife, 38200, Spain
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34
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Abstract
Proper chromosome segregation is critical for the maintenance of genomic information in every cell division, which is required for cell survival. Cells have orchestrated a myriad of control mechanisms to guarantee proper chromosome segregation. Upon stress, cells induce a number of adaptive responses to maximize survival that range from regulation of gene expression to control of cell-cycle progression. We have found here that in response to osmostress, cells also regulate mitosis to ensure proper telomeric and rDNA segregation during adaptation. Osmostress induces a Hog1-dependent delay of cell-cycle progression in early mitosis by phosphorylating Net1, thereby impairing timely nucleolar release and activation of Cdc14, core elements of mitosis regulation. Thus, Hog1 activation prevents segregation defects to maximize survival. Adaptation to environmental changes is crucial for cell fitness. In Saccharomyces cerevisiae, variations in external osmolarity trigger the activation of the stress-activated protein kinase Hog1 (high-osmolarity glycerol 1), which regulates gene expression, metabolism, and cell-cycle progression. The activation of this kinase leads to the regulation of G1, S, and G2 phases of the cell cycle to prevent genome instability and promote cell survival. Here we show that Hog1 delays mitotic exit when cells are stressed during metaphase. Hog1 phosphorylates the nucleolar protein Net1, altering its affinity for the phosphatase Cdc14, whose activity is essential for mitotic exit and completion of the cell cycle. The untimely release of Cdc14 from the nucleolus upon activation of Hog1 is linked to a defect in ribosomal DNA (rDNA) and telomere segregation, and it ultimately delays cell division. A mutant of Net1 that cannot be phosphorylated by Hog1 displays reduced viability upon osmostress. Thus, Hog1 contributes to maximizing cell survival upon stress by regulating mitotic exit.
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35
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Mittal P, Ghule K, Trakroo D, Prajapati HK, Ghosh SK. Meiosis-Specific Functions of Kinesin Motors in Cohesin Removal and Maintenance of Chromosome Integrity in Budding Yeast. Mol Cell Biol 2020; 40:e00386-19. [PMID: 31964755 PMCID: PMC7108822 DOI: 10.1128/mcb.00386-19] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Revised: 09/20/2019] [Accepted: 12/26/2019] [Indexed: 12/31/2022] Open
Abstract
Kinesin motors provide the molecular forces at the kinetochore-microtubule interface and along the spindle to control chromosome segregation. During meiosis with two rounds of microtubule assembly-disassembly, the roles of motor proteins remain unexplored. We observed that in contrast to mitosis, Cin8 and Kip3 together are indispensable for meiosis. While examining meiosis in cin8Δ kip3Δ cells, we detected chromosome breakage in the meiosis II cells. The double mutant exhibits a delay in cohesin removal during anaphase I. Consequently, some cells fail to undergo meiosis II and form dyads, while some, as they progress through meiosis II, cause a defect in chromosome integrity. We believe that in the latter cells, an imbalance of spindle-mediated force and the simultaneous persistence of cohesin on chromosomes cause their breakage. We provide evidence that tension generated by Cin8 and Kip3 through microtubule cross-linking is essential for signaling efficient cohesin removal and the maintenance of chromosome integrity during meiosis.
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Affiliation(s)
- Priyanka Mittal
- National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Komal Ghule
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Bombay, Powai, Mumbai, India
| | - Deepika Trakroo
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Bombay, Powai, Mumbai, India
| | - Hemant Kumar Prajapati
- National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Santanu K Ghosh
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Bombay, Powai, Mumbai, India
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The Multiple Roles of the Cdc14 Phosphatase in Cell Cycle Control. Int J Mol Sci 2020; 21:ijms21030709. [PMID: 31973188 PMCID: PMC7038166 DOI: 10.3390/ijms21030709] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 01/17/2020] [Accepted: 01/20/2020] [Indexed: 12/20/2022] Open
Abstract
The Cdc14 phosphatase is a key regulator of mitosis in the budding yeast Saccharomyces cerevisiae. Cdc14 was initially described as playing an essential role in the control of cell cycle progression by promoting mitotic exit on the basis of its capacity to counteract the activity of the cyclin-dependent kinase Cdc28/Cdk1. A compiling body of evidence, however, has later demonstrated that this phosphatase plays other multiple roles in the regulation of mitosis at different cell cycle stages. Here, we summarize our current knowledge about the pivotal role of Cdc14 in cell cycle control, with a special focus in the most recently uncovered functions of the phosphatase.
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37
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Protein Phosphatases in G1 Regulation. Int J Mol Sci 2020; 21:ijms21020395. [PMID: 31936296 PMCID: PMC7013402 DOI: 10.3390/ijms21020395] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 12/29/2019] [Accepted: 12/31/2019] [Indexed: 01/15/2023] Open
Abstract
Eukaryotic cells make the decision to proliferate, to differentiate or to cease dividing during G1, before passage through the restriction point or Start. Keeping cyclin-dependent kinase (CDK) activity low during this period restricts commitment to a new cell cycle and is essential to provide the adequate timeframe for the sensing of environmental signals. Here, we review the role of protein phosphatases in the modulation of CDK activity and as the counteracting force for CDK-dependent substrate phosphorylation, in budding and fission yeast. Moreover, we discuss recent findings that place protein phosphatases in the interface between nutritional signalling pathways and the cell cycle machinery.
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PP2A Functions during Mitosis and Cytokinesis in Yeasts. Int J Mol Sci 2019; 21:ijms21010264. [PMID: 31906018 PMCID: PMC6981662 DOI: 10.3390/ijms21010264] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 12/23/2019] [Accepted: 12/24/2019] [Indexed: 12/13/2022] Open
Abstract
Protein phosphorylation is a common mechanism for the regulation of cell cycle progression. The opposing functions of cell cycle kinases and phosphatases are crucial for accurate chromosome segregation and exit from mitosis. Protein phosphatases 2A are heterotrimeric complexes that play essential roles in cell growth, proliferation, and regulation of the cell cycle. Here, we review the function of the protein phosphatase 2A family as the counteracting force for the mitotic kinases. We focus on recent findings in the regulation of mitotic exit and cytokinesis by PP2A phosphatases in S. cerevisiae and other fungal species.
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Sherwin D, Wang Y. The Opposing Functions of Protein Kinases and Phosphatases in Chromosome Bipolar Attachment. Int J Mol Sci 2019; 20:ijms20246182. [PMID: 31817904 PMCID: PMC6940769 DOI: 10.3390/ijms20246182] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 11/22/2019] [Accepted: 12/06/2019] [Indexed: 01/17/2023] Open
Abstract
Accurate chromosome segregation during cell division is essential to maintain genome integrity in all eukaryotic cells, and chromosome missegregation leads to aneuploidy and therefore represents a hallmark of many cancers. Accurate segregation requires sister kinetochores to attach to microtubules emanating from opposite spindle poles, known as bipolar attachment or biorientation. Recent studies have uncovered several mechanisms critical to chromosome bipolar attachment. First, a mechanism exists to ensure that the conformation of sister centromeres is biased toward bipolar attachment. Second, the phosphorylation of some kinetochore proteins destabilizes kinetochore attachment to facilitate error correction, but a protein phosphatase reverses this phosphorylation. Moreover, the activity of the spindle assembly checkpoint is regulated by kinases and phosphatases at the kinetochore, and this checkpoint prevents anaphase entry in response to faulty kinetochore attachment. The fine-tuned kinase/phosphatase balance at kinetochores is crucial for faithful chromosome segregation during both mitosis and meiosis. Here, we discuss the function and regulation of protein phosphatases in the establishment of chromosome bipolar attachment with a focus on the model organism budding yeast.
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Affiliation(s)
| | - Yanchang Wang
- Correspondence: ; Tel.: +1-850-644-0402; Fax: +1-850-644-5781
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40
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Játiva S, Calabria I, Moyano-Rodriguez Y, Garcia P, Queralt E. Cdc14 activation requires coordinated Cdk1-dependent phosphorylation of Net1 and PP2A-Cdc55 at anaphase onset. Cell Mol Life Sci 2019; 76:3601-3620. [PMID: 30927017 PMCID: PMC11105415 DOI: 10.1007/s00018-019-03086-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 03/04/2019] [Accepted: 03/25/2019] [Indexed: 01/21/2023]
Abstract
Exit from mitosis and completion of cytokinesis require the inactivation of mitotic cyclin-dependent kinase (Cdk) activity. In budding yeast, Cdc14 phosphatase is a key mitotic regulator that is activated in anaphase to counteract Cdk activity. In metaphase, Cdc14 is kept inactive in the nucleolus, where it is sequestered by its inhibitor, Net1. At anaphase onset, downregulation of PP2ACdc55 phosphatase by separase and Zds1 protein promotes Net1 phosphorylation and, consequently, Cdc14 release from the nucleolus. The mechanism by which PP2ACdc55 activity is downregulated during anaphase remains to be elucidated. Here, we demonstrate that Cdc55 regulatory subunit is phosphorylated in anaphase in a Cdk1-Clb2-dependent manner. Interestingly, cdc55-ED phosphomimetic mutant inactivates PP2ACdc55 phosphatase activity towards Net1 and promotes Cdc14 activation. Separase and Zds1 facilitate Cdk-dependent Net1 phosphorylation and Cdc14 release from the nucleolus by modulating PP2ACdc55 activity via Cdc55 phosphorylation. In addition, human Cdk1-CyclinB1 phosphorylates human B55, indicating that the mechanism is conserved in higher eukaryotes.
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Affiliation(s)
- Soraya Játiva
- Cell Cycle Group, Cancer Epigenetics and Biology Program (PEBC), Institut d'Investigacions Biomèdica de Bellvitge (IDIBELL), Av. Gran Via de L'Hospitalet 199-203, 08908, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Ines Calabria
- Cell Cycle Group, Cancer Epigenetics and Biology Program (PEBC), Institut d'Investigacions Biomèdica de Bellvitge (IDIBELL), Av. Gran Via de L'Hospitalet 199-203, 08908, L'Hospitalet de Llobregat, Barcelona, Spain
- Genomics Unit, Medical Research Institute La Fe, Valencia, Spain
| | - Yolanda Moyano-Rodriguez
- Cell Cycle Group, Cancer Epigenetics and Biology Program (PEBC), Institut d'Investigacions Biomèdica de Bellvitge (IDIBELL), Av. Gran Via de L'Hospitalet 199-203, 08908, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Patricia Garcia
- Cell Cycle Group, Cancer Epigenetics and Biology Program (PEBC), Institut d'Investigacions Biomèdica de Bellvitge (IDIBELL), Av. Gran Via de L'Hospitalet 199-203, 08908, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Ethel Queralt
- Cell Cycle Group, Cancer Epigenetics and Biology Program (PEBC), Institut d'Investigacions Biomèdica de Bellvitge (IDIBELL), Av. Gran Via de L'Hospitalet 199-203, 08908, L'Hospitalet de Llobregat, Barcelona, Spain.
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Abstract
Eukaryotic cell division has been studied thoroughly and is understood in great mechanistic detail. Paradoxically, however, we lack an understanding of its core control process, in which the master regulator of the cell cycle, cyclin-dependent kinase (CDK), temporally coordinates an array of complex molecular events. The core elements of the CDK control system are conserved in eukaryotic cells, which contain multiple cyclin–CDK forms that have poorly defined and partially overlapping responsibilities in the cell cycle. However, a single CDK can drive all events of cell division in both mammalian and yeast cells, and in fission yeast a single mitotic cyclin can drive the cell cycle without major problems. But how can the same CDK induce different events when activated at different times during the cell cycle? This question, which has bewildered cell cycle researchers for decades, now has a sufficiently clear mechanistic answer. This Perspective aims to provide a synthesis of recent data to facilitate a better understanding of this central cellular control system.
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Affiliation(s)
- Mihkel Örd
- Institute of Technology, University of Tartu, 50411 Tartu, Estonia
| | - Mart Loog
- Institute of Technology, University of Tartu, 50411 Tartu, Estonia
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42
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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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Örd M, Venta R, Möll K, Valk E, Loog M. Cyclin-Specific Docking Mechanisms Reveal the Complexity of M-CDK Function in the Cell Cycle. Mol Cell 2019; 75:76-89.e3. [PMID: 31101497 PMCID: PMC6620034 DOI: 10.1016/j.molcel.2019.04.026] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 03/28/2019] [Accepted: 04/19/2019] [Indexed: 11/20/2022]
Abstract
Cyclin-dependent kinases (CDKs) coordinate hundreds of molecular events during the cell cycle. Multiple cyclins are involved, but the global role of cyclin-specific phosphorylation has remained unsolved. We uncovered a cyclin docking motif, LxF, that mediates binding of replication factor Cdc6 to mitotic cyclin. This interaction leads to phospho-adaptor Cks1-mediated inhibition of M-CDK to facilitate Cdc6 accumulation and sequestration in mitosis. The LxF motif and Cks1 also mediate the mutual inhibition between M-CDK and the tyrosine kinase Swe1. Additionally, the LxF motif is critical for targeting M-CDK to phosphorylate several mitotic regulators; for example, Spo12 is targeted via LxF to release the phosphatase Cdc14. The results complete the full set of G1, S, and M-CDK docking mechanisms and outline the unified role of cyclin specificity and CDK activity thresholds. Cooperation of cyclin and Cks1 docking creates a variety of CDK thresholds and switching orders, including combinations of last in, first out (LIFO) and first in, first out (FIFO) ordering. Mitotic cyclin Clb2 binds a specific linear motif, LxF, in targets or inhibitors LxF interaction enhances mitotic CDK substrate phosphorylation Phospho-adaptor Cks1 and the LxF docking mediate CDK inhibition by Cdc6 and Swe1 Cyclin-specific targeting enables finetuning of CDK function
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Affiliation(s)
- Mihkel Örd
- Institute of Technology, University of Tartu, Tartu 50411, Estonia
| | - Rainis Venta
- Institute of Technology, University of Tartu, Tartu 50411, Estonia
| | - Kaidi Möll
- Institute of Technology, University of Tartu, Tartu 50411, Estonia
| | - Ervin Valk
- Institute of Technology, University of Tartu, Tartu 50411, Estonia
| | - Mart Loog
- Institute of Technology, University of Tartu, Tartu 50411, Estonia.
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44
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Ariño J, Velázquez D, Casamayor A. Ser/Thr protein phosphatases in fungi: structure, regulation and function. MICROBIAL CELL 2019; 6:217-256. [PMID: 31114794 PMCID: PMC6506691 DOI: 10.15698/mic2019.05.677] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Reversible phospho-dephosphorylation of proteins is a major mechanism for the control of cellular functions. By large, Ser and Thr are the most frequently residues phosphorylated in eukar-yotes. Removal of phosphate from these amino acids is catalyzed by a large family of well-conserved enzymes, collectively called Ser/Thr protein phosphatases. The activity of these enzymes has an enormous impact on cellular functioning. In this work we pre-sent the members of this family in S. cerevisiae and other fungal species, and review the most recent findings concerning their regu-lation and the roles they play in the most diverse aspects of cell biology.
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Affiliation(s)
- Joaquín Ariño
- Departament de Bioquímica i Biologia Molecular and Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona, Spain
| | - Diego Velázquez
- Departament de Bioquímica i Biologia Molecular and Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona, Spain
| | - Antonio Casamayor
- Departament de Bioquímica i Biologia Molecular and Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona, Spain
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45
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Münzner U, Klipp E, Krantz M. A comprehensive, mechanistically detailed, and executable model of the cell division cycle in Saccharomyces cerevisiae. Nat Commun 2019; 10:1308. [PMID: 30899000 PMCID: PMC6428898 DOI: 10.1038/s41467-019-08903-w] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Accepted: 01/24/2019] [Indexed: 01/31/2023] Open
Abstract
Understanding how cellular functions emerge from the underlying molecular mechanisms is a key challenge in biology. This will require computational models, whose predictive power is expected to increase with coverage and precision of formulation. Genome-scale models revolutionised the metabolic field and made the first whole-cell model possible. However, the lack of genome-scale models of signalling networks blocks the development of eukaryotic whole-cell models. Here, we present a comprehensive mechanistic model of the molecular network that controls the cell division cycle in Saccharomyces cerevisiae. We use rxncon, the reaction-contingency language, to neutralise the scalability issues preventing formulation, visualisation and simulation of signalling networks at the genome-scale. We use parameter-free modelling to validate the network and to predict genotype-to-phenotype relationships down to residue resolution. This mechanistic genome-scale model offers a new perspective on eukaryotic cell cycle control, and opens up for similar models-and eventually whole-cell models-of human cells.
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Affiliation(s)
- Ulrike Münzner
- Humboldt-Universität zu Berlin, Institute of Biology, Theoretical Biophysics, Berlin, 10099, Germany
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Kyoto, 611-0011, Japan
| | - Edda Klipp
- Humboldt-Universität zu Berlin, Institute of Biology, Theoretical Biophysics, Berlin, 10099, Germany
| | - Marcus Krantz
- Humboldt-Universität zu Berlin, Institute of Biology, Theoretical Biophysics, Berlin, 10099, Germany.
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46
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Campbell IW, Zhou X, Amon A. The Mitotic Exit Network integrates temporal and spatial signals by distributing regulation across multiple components. eLife 2019; 8:41139. [PMID: 30672733 PMCID: PMC6363386 DOI: 10.7554/elife.41139] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 01/10/2019] [Indexed: 12/30/2022] Open
Abstract
GTPase signal transduction pathways control cellular decision making by integrating multiple cellular events into a single signal. The Mitotic Exit Network (MEN), a Ras-like GTPase signaling pathway, integrates spatial and temporal cues to ensure that cytokinesis only occurs after the genome has partitioned between mother and daughter cells during anaphase. Here we show that signal integration does not occur at a single step of the pathway. Rather, sequential components of the pathway are controlled in series by different signals. The spatial signal, nuclear position, regulates the MEN GTPase Tem1. The temporal signal, commencement of anaphase, is mediated by mitotic cyclin-dependent kinase (CDK) phosphorylation of the GTPase's downstream kinases. We propose that integrating multiple signals through sequential steps in the GTPase pathway represents a generalizable principle in GTPase signaling and explains why intracellular signal transmission is a multi-step process. Serial signal integration rather than signal amplification makes multi-step signal transduction necessary.
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Affiliation(s)
- Ian Winsten Campbell
- David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, United States
| | - Xiaoxue Zhou
- David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, United States
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47
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Baro B, Játiva S, Calabria I, Vinaixa J, Bech-Serra JJ, de LaTorre C, Rodrigues J, Hernáez ML, Gil C, Barceló-Batllori S, Larsen MR, Queralt E. SILAC-based phosphoproteomics reveals new PP2A-Cdc55-regulated processes in budding yeast. Gigascience 2018; 7:4982941. [PMID: 29688323 PMCID: PMC5967524 DOI: 10.1093/gigascience/giy047] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 04/18/2018] [Indexed: 01/12/2023] Open
Abstract
Background Protein phosphatase 2A (PP2A) is a family of conserved serine/threonine phosphatases involved in several essential aspects of cell growth and proliferation. PP2ACdc55 phosphatase has been extensively related to cell cycle events in budding yeast; however, few PP2ACdc55 substrates have been identified. Here, we performed a quantitative mass spectrometry approach to reveal new substrates of PP2ACdc55 phosphatase and new PP2A-related processes in mitotic arrested cells. Results We identified 62 statistically significant PP2ACdc55 substrates involved mainly in actin-cytoskeleton organization. In addition, we validated new PP2ACdc55 substrates such as Slk19 and Lte1, involved in early and late anaphase pathways, and Zeo1, a component of the cell wall integrity pathway. Finally, we constructed docking models of Cdc55 and its substrate Mob1. We found that the predominant interface on Cdc55 is mediated by a protruding loop consisting of residues 84–90, thus highlighting the relevance of these aminoacids for substrate interaction. Conclusions We used phosphoproteomics of Cdc55-deficient cells to uncover new PP2ACdc55 substrates and functions in mitosis. As expected, several hyperphosphorylated proteins corresponded to Cdk1-dependent substrates, although other kinases’ consensus motifs were also enriched in our dataset, suggesting that PP2ACdc55 counteracts and regulates other kinases distinct from Cdk1. Indeed, Pkc1 emerged as a novel node of PP2ACdc55 regulation, highlighting a major role of PP2ACdc55 in actin cytoskeleton and cytokinesis, gene ontology terms significantly enriched in the PP2ACdc55-dependent phosphoproteome.
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Affiliation(s)
- Barbara Baro
- Cell Cycle Group, Cancer Epigenetics and Biology Program, Institut d'Investigacions Biomèdica de Bellvitge (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Spain
| | - Soraya Játiva
- Cell Cycle Group, Cancer Epigenetics and Biology Program, Institut d'Investigacions Biomèdica de Bellvitge (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Spain
| | - Inés Calabria
- Cell Cycle Group, Cancer Epigenetics and Biology Program, Institut d'Investigacions Biomèdica de Bellvitge (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Spain
| | - Judith Vinaixa
- Cell Cycle Group, Cancer Epigenetics and Biology Program, Institut d'Investigacions Biomèdica de Bellvitge (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Spain
| | - Joan-Josep Bech-Serra
- IDIBELL Proteomics Unit, Institut d'Investigacions Biomèdica de Bellvitge, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Carolina de LaTorre
- IDIBELL Proteomics Unit, Institut d'Investigacions Biomèdica de Bellvitge, L'Hospitalet de Llobregat, Barcelona, Spain
| | - João Rodrigues
- Structural Biology Department, School of Medicine, Stanford, California, USA
| | - María Luisa Hernáez
- Proteomics Unit, Parque Científico de Madrid, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain
| | - Concha Gil
- Proteomics Unit, Parque Científico de Madrid, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain
| | - Silvia Barceló-Batllori
- IDIBELL Proteomics Unit, Institut d'Investigacions Biomèdica de Bellvitge, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Martin R Larsen
- Department of Biochemistry and Molecular Biology, Odense M, Denmark
| | - Ethel Queralt
- Cell Cycle Group, Cancer Epigenetics and Biology Program, Institut d'Investigacions Biomèdica de Bellvitge (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Spain
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48
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Touati SA, Kataria M, Jones AW, Snijders AP, Uhlmann F. Phosphoproteome dynamics during mitotic exit in budding yeast. EMBO J 2018; 37:embj.201798745. [PMID: 29650682 PMCID: PMC5978319 DOI: 10.15252/embj.201798745] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 03/01/2018] [Accepted: 03/20/2018] [Indexed: 11/09/2022] Open
Abstract
The cell division cycle culminates in mitosis when two daughter cells are born. As cyclin-dependent kinase (Cdk) activity reaches its peak, the anaphase-promoting complex/cyclosome (APC/C) is activated to trigger sister chromatid separation and mitotic spindle elongation, followed by spindle disassembly and cytokinesis. Degradation of mitotic cyclins and activation of Cdk-counteracting phosphatases are thought to cause protein dephosphorylation to control these sequential events. Here, we use budding yeast to analyze phosphorylation dynamics of 3,456 phosphosites on 1,101 proteins with high temporal resolution as cells progress synchronously through mitosis. This reveals that successive inactivation of S and M phase Cdks and of the mitotic kinase Polo contributes to order these dephosphorylation events. Unexpectedly, we detect as many new phosphorylation events as there are dephosphorylation events. These correlate with late mitotic kinase activation and identify numerous candidate targets of these kinases. These findings revise our view of mitotic exit and portray it as a dynamic process in which a range of mitotic kinases contribute to order both protein dephosphorylation and phosphorylation.
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Affiliation(s)
- Sandra A Touati
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, UK
| | - Meghna Kataria
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, UK
| | - Andrew W Jones
- Mass Spectrometry Proteomics Science Technology Platform, The Francis Crick Institute, London, UK
| | - Ambrosius P Snijders
- Mass Spectrometry Proteomics Science Technology Platform, The Francis Crick Institute, London, UK
| | - Frank Uhlmann
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, UK
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49
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Lianga N, Doré C, Kennedy EK, Yeh E, Williams EC, Fortinez CM, Wang A, Bloom KS, Rudner AD. Cdk1 phosphorylation of Esp1/Separase functions with PP2A and Slk19 to regulate pericentric Cohesin and anaphase onset. PLoS Genet 2018; 14:e1007029. [PMID: 29561844 PMCID: PMC5880407 DOI: 10.1371/journal.pgen.1007029] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 04/02/2018] [Accepted: 09/17/2017] [Indexed: 12/27/2022] Open
Abstract
Anaphase onset is an irreversible cell cycle transition that is triggered by the activation of the protease Separase. Separase cleaves the Mcd1 (also known as Scc1) subunit of Cohesin, a complex of proteins that physically links sister chromatids, triggering sister chromatid separation. Separase is regulated by the degradation of the anaphase inhibitor Securin which liberates Separase from inhibitory Securin/Separase complexes. In many organisms, Securin is not essential suggesting that Separase is regulated by additional mechanisms. In this work, we show that in budding yeast Cdk1 activates Separase (Esp1 in yeast) through phosphorylation to trigger anaphase onset. Esp1 activation is opposed by protein phosphatase 2A associated with its regulatory subunit Cdc55 (PP2ACdc55) and the spindle protein Slk19. Premature anaphase spindle elongation occurs when Securin (Pds1 in yeast) is inducibly degraded in cells that also contain phospho-mimetic mutations in ESP1, or deletion of CDC55 or SLK19. This striking phenotype is accompanied by advanced degradation of Mcd1, disruption of pericentric Cohesin organization and chromosome mis-segregation. Our findings suggest that PP2ACdc55 and Slk19 function redundantly with Pds1 to inhibit Esp1 within pericentric chromatin, and both Pds1 degradation and Cdk1-dependent phosphorylation of Esp1 act together to trigger anaphase onset.
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Affiliation(s)
- Noel Lianga
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Carole Doré
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Erin K. Kennedy
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Elaine Yeh
- University of North Carolina, Chapel Hill, Department of Biology, Chapel Hill, NC, United States of America
| | - Elizabeth C. Williams
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Camille Marie Fortinez
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Alick Wang
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Kerry S. Bloom
- University of North Carolina, Chapel Hill, Department of Biology, Chapel Hill, NC, United States of America
| | - Adam D. Rudner
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
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50
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Botchkarev VV, Haber JE. Functions and regulation of the Polo-like kinase Cdc5 in the absence and presence of DNA damage. Curr Genet 2018; 64:87-96. [PMID: 28770345 PMCID: PMC6249032 DOI: 10.1007/s00294-017-0727-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 07/24/2017] [Accepted: 07/26/2017] [Indexed: 12/20/2022]
Abstract
Polo-like kinases are essential cell cycle regulators that are conserved from yeast to humans. Unlike higher eukaryotes, who express multiple Polo-like kinase family members that perform many important functions, budding yeast express only a single Polo-like kinase, Cdc5, which is the homolog of mammalian cell cycle master regulator Polo-like kinase 1. Cdc5 is a fascinating multifaceted protein that is programmed to target its many substrates in a timely, sequential manner to ensure proper cell cycle progression. Over the years, many lessons about Polo-like kinase 1 have been learned by studying Cdc5 in budding yeast. Cdc5 has been well documented in regulating mitotic entry, chromosome segregation, mitotic exit, and cytokinesis. Cdc5 also plays important roles during cell division after DNA damage. Here, we briefly review the many functions of Cdc5 and its regulation in the absence and presence of DNA damage.
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Affiliation(s)
- Vladimir V Botchkarev
- Department of Biology, Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, MA, 02454, USA
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, 02215, USA
- Department of Genetics, Harvard Medical School, Boston, MA, 02115, USA
| | - James E Haber
- Department of Biology, Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, MA, 02454, USA.
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