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Szulc NA, Stefaniak F, Piechota M, Soszyńska A, Piórkowska G, Cappannini A, Bujnicki J, Maniaci C, Pokrzywa W. DEGRONOPEDIA: a web server for proteome-wide inspection of degrons. Nucleic Acids Res 2024; 52:W221-W232. [PMID: 38567734 PMCID: PMC11223883 DOI: 10.1093/nar/gkae238] [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: 02/02/2024] [Revised: 03/12/2024] [Accepted: 03/20/2024] [Indexed: 07/06/2024] Open
Abstract
E3 ubiquitin ligases recognize substrates through their short linear motifs termed degrons. While degron-signaling has been a subject of extensive study, resources for its systematic screening are limited. To bridge this gap, we developed DEGRONOPEDIA, a web server that searches for degrons and maps them to nearby residues that can undergo ubiquitination and disordered regions, which may act as protein unfolding seeds. Along with an evolutionary assessment of degron conservation, the server also reports on post-translational modifications and mutations that may modulate degron availability. Acknowledging the prevalence of degrons at protein termini, DEGRONOPEDIA incorporates machine learning to assess N-/C-terminal stability, supplemented by simulations of proteolysis to identify degrons in newly formed termini. An experimental validation of a predicted C-terminal destabilizing motif, coupled with the confirmation of a post-proteolytic degron in another case, exemplifies its practical application. DEGRONOPEDIA can be freely accessed at degronopedia.com.
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Affiliation(s)
- Natalia A Szulc
- Laboratory of Protein Metabolism, International Institute of Molecular and Cell Biology in Warsaw, 4 Ks. Trojdena Str., 02-109 Warsaw, Poland
| | - Filip Stefaniak
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, 4 Ks. Trojdena Str., 02-109 Warsaw, Poland
| | - Małgorzata Piechota
- Laboratory of Protein Metabolism, International Institute of Molecular and Cell Biology in Warsaw, 4 Ks. Trojdena Str., 02-109 Warsaw, Poland
| | - Anna Soszyńska
- Laboratory of Protein Metabolism, International Institute of Molecular and Cell Biology in Warsaw, 4 Ks. Trojdena Str., 02-109 Warsaw, Poland
| | - Gabriela Piórkowska
- Laboratory of Protein Metabolism, International Institute of Molecular and Cell Biology in Warsaw, 4 Ks. Trojdena Str., 02-109 Warsaw, Poland
| | - Andrea Cappannini
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, 4 Ks. Trojdena Str., 02-109 Warsaw, Poland
| | - Janusz M Bujnicki
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, 4 Ks. Trojdena Str., 02-109 Warsaw, Poland
| | - Chiara Maniaci
- Medical Research Council (MRC) Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Wojciech Pokrzywa
- Laboratory of Protein Metabolism, International Institute of Molecular and Cell Biology in Warsaw, 4 Ks. Trojdena Str., 02-109 Warsaw, Poland
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2
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Ostapenko D, Solomon MJ. APC Cdh1-mediated degradation of Cdh1 is necessary for faithful meiotic chromosome segregation in S. cerevisiae. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.01.601619. [PMID: 39005361 PMCID: PMC11245022 DOI: 10.1101/2024.07.01.601619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
The Anaphase-Promoting Complex/Cyclosome (APC/C) is a ubiquitin ligase that promotes the ubiquitination and subsequent degradation of numerous cell cycle regulators during mitosis and in G1. Proteins are recruited to the APC/C by activator proteins such as Cdh1. During the cell cycle, Cdh1 is subject to precise regulation so that substrates are not degraded prematurely. We have explored the regulation of Cdh1 during the developmental transition into meiosis and sporulation in the budding yeast S. cerevisiae. Transition to sporulation medium triggers the degradation of Cdh1. Cdh1 degradation is mediated by the APC/C itself in a "trans" mechanism in which one molecule of Cdh1 recruits a second molecule of Cdh1 to the APC/C for ubiquitination. Degradation requires an intact glucose-sensing SNF1 protein kinase complex (orthologous to the mammalian AMPK nutritional sensor), which directly phosphorylates Cdh1 on Ser-200 within an unstructured N-terminal region. In the absence of phosphorylation, expression of a Cdh1-S200A mutant is fully stabilized, leading to chromosome instability and loss of viability. We hypothesize that Cdh1 degradation is necessary for the preservation of cell cycle regulators and chromosome cohesion proteins between the reductional and equational meiotic divisions, which occur without the intervening Gap or S phases found in mitotic cell cycles.
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Affiliation(s)
- Denis Ostapenko
- Yale University, Department of Molecular Biophysics and Biochemistry, 266 Whitney Avenue, New Haven, CT 06520-8114
| | - Mark J. Solomon
- Yale University, Department of Molecular Biophysics and Biochemistry, 266 Whitney Avenue, New Haven, CT 06520-8114
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3
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Xu H, Hu R, Zhao Z. DegronMD: Leveraging Evolutionary and Structural Features for Deciphering Protein-Targeted Degradation, Mutations, and Drug Response to Degrons. Mol Biol Evol 2023; 40:msad253. [PMID: 37992195 DOI: 10.1093/molbev/msad253] [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: 07/03/2023] [Revised: 10/18/2023] [Accepted: 11/09/2023] [Indexed: 11/24/2023] Open
Abstract
Protein-targeted degradation is an emerging and promising therapeutic approach. The specificity of degradation and the maintenance of cellular homeostasis are determined by the interactions between E3 ubiquitin ligase and degradation signals, known as degrons. The human genome encodes over 600 E3 ligases; however, only a small number of targeted degron instances have been identified so far. In this study, we introduced DegronMD, an open knowledgebase designed for the investigation of degrons, their associated dysfunctional events, and drug responses. We revealed that degrons are evolutionarily conserved and tend to occur near the sites of protein translational modifications, particularly in the regions of disordered structure and higher solvent accessibility. Through pattern recognition and machine learning techniques, we constructed the degrome landscape across the human proteome, yielding over 18,000 new degrons for targeted protein degradation. Furthermore, dysfunction of degrons disrupts the degradation process and leads to the abnormal accumulation of proteins; this process is associated with various types of human cancers. Based on the estimated phenotypic changes induced by somatic mutations, we systematically quantified and assessed the impact of mutations on degron function in pan-cancers; these results helped to build a global mutational map on human degrome, including 89,318 actionable mutations that may induce the dysfunction of degrons and disrupt protein degradation pathways. Multiomics integrative analysis unveiled over 400 drug resistance events associated with the mutations in functional degrons. DegronMD, accessible at https://bioinfo.uth.edu/degronmd, is a useful resource to explore the biological mechanisms, infer protein degradation, and assist with drug discovery and design on degrons.
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Affiliation(s)
- Haodong Xu
- Department of Orthopaedics, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China
- Center for Precision Health, School of Biomedical Informatics, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Ruifeng Hu
- Center for Precision Health, School of Biomedical Informatics, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
- Center for Advanced Parkinson Research, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Genomics and Bioinformatics Hub, Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Zhongming Zhao
- Center for Precision Health, School of Biomedical Informatics, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
- MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX 77030, USA
- Human Genetics Center, School of Public Health, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
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4
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Houston J, Ohta M, Gómez-Cavazos JS, Deep A, Corbett KD, Oegema K, Lara-Gonzalez P, Kim T, Desai A. BUB-1-bound PLK-1 directs CDC-20 kinetochore recruitment to ensure timely embryonic mitoses. Curr Biol 2023; 33:2291-2299.e10. [PMID: 37137308 PMCID: PMC10270731 DOI: 10.1016/j.cub.2023.04.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 03/13/2023] [Accepted: 04/12/2023] [Indexed: 05/05/2023]
Abstract
During mitosis, chromosomes assemble kinetochores to dynamically couple with spindle microtubules.1,2 Kinetochores also function as signaling hubs directing mitotic progression by recruiting and controlling the fate of the anaphase promoting complex/cyclosome (APC/C) activator CDC-20.3,4,5 Kinetochores either incorporate CDC-20 into checkpoint complexes that inhibit the APC/C or dephosphorylate CDC-20, which allows it to interact with and activate the APC/C.4,6 The importance of these two CDC-20 fates likely depends on the biological context. In human somatic cells, the major mechanism controlling mitotic progression is the spindle checkpoint. By contrast, progression through mitosis during the cell cycles of early embryos is largely checkpoint independent.7,8,9,10 Here, we first show that CDC-20 phosphoregulation controls mitotic duration in the C. elegans embryo and defines a checkpoint-independent temporal mitotic optimum for robust embryogenesis. CDC-20 phosphoregulation occurs at kinetochores and in the cytosol. At kinetochores, the flux of CDC-20 for local dephosphorylation requires an ABBA motif on BUB-1 that directly interfaces with the structured WD40 domain of CDC-20.6,11,12,13 We next show that a conserved "STP" motif in BUB-1 that docks the mitotic kinase PLK-114 is necessary for CDC-20 kinetochore recruitment and timely mitotic progression. The kinase activity of PLK-1 is required for CDC-20 to localize to kinetochores and phosphorylates the CDC-20-binding ABBA motif of BUB-1 to promote BUB-1-CDC-20 interaction and mitotic progression. Thus, the BUB-1-bound pool of PLK-1 ensures timely mitosis during embryonic cell cycles by promoting CDC-20 recruitment to the vicinity of kinetochore-localized phosphatase activity.
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Affiliation(s)
- Jack Houston
- Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA; Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Ludwig Institute for Cancer Research, La Jolla, CA 92093, USA
| | - Midori Ohta
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Ludwig Institute for Cancer Research, La Jolla, CA 92093, USA
| | - J Sebastián Gómez-Cavazos
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Department of Cell and Developmental Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Amar Deep
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kevin D Corbett
- Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA; Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Karen Oegema
- Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA; Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Ludwig Institute for Cancer Research, La Jolla, CA 92093, USA; Department of Cell and Developmental Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Pablo Lara-Gonzalez
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Ludwig Institute for Cancer Research, La Jolla, CA 92093, USA; Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA
| | - Taekyung Kim
- Ludwig Institute for Cancer Research, La Jolla, CA 92093, USA; Department of Biology Education, Pusan National University, Busan 46241, Republic of Korea.
| | - Arshad Desai
- Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA; Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Ludwig Institute for Cancer Research, La Jolla, CA 92093, USA; Department of Cell and Developmental Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA.
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5
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Willems A, Liang Y, Heyman J, Depuydt T, Eekhout T, Canher B, Van den Daele H, Vercauteren I, Vandepoele K, De Veylder L. Plant lineage-specific PIKMIN1 drives APC/CCCS52A2 E3-ligase activity-dependent cell division. PLANT PHYSIOLOGY 2023; 191:1574-1595. [PMID: 36423220 PMCID: PMC10022622 DOI: 10.1093/plphys/kiac528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 11/18/2022] [Indexed: 06/16/2023]
Abstract
The anaphase-promoting complex/cyclosome (APC/C) marks key cell cycle proteins for proteasomal breakdown, thereby ensuring unidirectional progression through the cell cycle. Its target recognition is temporally regulated by activating subunits, one of which is called CELL CYCLE SWITCH 52 A2 (CCS52A2). We sought to expand the knowledge on the APC/C by using the severe growth phenotypes of CCS52A2-deficient Arabidopsis (Arabidopsis thaliana) plants as a readout in a suppressor mutagenesis screen, resulting in the identification of the previously undescribed gene called PIKMIN1 (PKN1). PKN1 deficiency rescues the disorganized root stem cell phenotype of the ccs52a2-1 mutant, whereas an excess of PKN1 inhibits the growth of ccs52a2-1 plants, indicating the need for control of PKN1 abundance for proper development. Accordingly, the lack of PKN1 in a wild-type background negatively impacts cell division, while its systemic overexpression promotes proliferation. PKN1 shows a cell cycle phase-dependent accumulation pattern, localizing to microtubular structures, including the preprophase band, the mitotic spindle, and the phragmoplast. PKN1 is conserved throughout the plant kingdom, with its function in cell division being evolutionarily conserved in the liverwort Marchantia polymorpha. Our data thus demonstrate that PKN1 represents a novel, plant-specific protein with a role in cell division that is likely proteolytically controlled by the CCS52A2-activated APC/C.
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Affiliation(s)
- Alex Willems
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent B-9052, Belgium
- Center for Plant Systems Biology, VIB, Ghent B-9052, Belgium
| | - Yuanke Liang
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent B-9052, Belgium
- Center for Plant Systems Biology, VIB, Ghent B-9052, Belgium
| | - Jefri Heyman
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent B-9052, Belgium
- Center for Plant Systems Biology, VIB, Ghent B-9052, Belgium
| | - Thomas Depuydt
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent B-9052, Belgium
- Center for Plant Systems Biology, VIB, Ghent B-9052, Belgium
| | - Thomas Eekhout
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent B-9052, Belgium
- Center for Plant Systems Biology, VIB, Ghent B-9052, Belgium
| | - Balkan Canher
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent B-9052, Belgium
- Center for Plant Systems Biology, VIB, Ghent B-9052, Belgium
| | - Hilde Van den Daele
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent B-9052, Belgium
- Center for Plant Systems Biology, VIB, Ghent B-9052, Belgium
| | - Ilse Vercauteren
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent B-9052, Belgium
- Center for Plant Systems Biology, VIB, Ghent B-9052, Belgium
| | - Klaas Vandepoele
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent B-9052, Belgium
- Center for Plant Systems Biology, VIB, Ghent B-9052, Belgium
| | - Lieven De Veylder
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent B-9052, Belgium
- Center for Plant Systems Biology, VIB, Ghent B-9052, Belgium
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6
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Barbhuiya TK, Fisher M, Boittier ED, Bolderson E, O'Byrne KJ, Richard DJ, Adams MN, Gandhi NS. Structural investigation of CDCA3-Cdh1 protein-protein interactions using in vitro studies and molecular dynamics simulation. Protein Sci 2023; 32:e4572. [PMID: 36691744 PMCID: PMC9926468 DOI: 10.1002/pro.4572] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 01/11/2023] [Accepted: 01/16/2023] [Indexed: 01/25/2023]
Abstract
The anaphase-promoting complex/cyclosome (APC/C) ubiquitin ligase and its cofactor, Cdh1, regulate the expression of several cell-cycle proteins and their functions during mitosis. Levels of the protein cell division cycle-associated protein 3 (CDCA3), which is functionally required for mitotic entry, are regulated by APC/CCdh1 . CDCA3 is an intrinsically disordered protein and contains both C-terminal KEN box and D-box recognition motifs, enabling binding to Cdh1. Our previous findings demonstrate that CDCA3 has a phosphorylation-dependent non-canonical ABBA-like motif within the linker region bridging these two recognition motifs and is required for efficient binding to Cdh1. Here, we sought to identify and further characterize additional residues that participate within this ABBA-like motif using detailed in vitro experiments and in silico modeling studies. We identified the role of H-bonds, hydrophobic and ionic interactions across the CDCA3 ABBA-like motif in the linker region between KEN and D-box motifs. This linker region adopts a well-defined structure when bound to Cdh1 in the presence of phosphorylation. Upon alanine mutation, the structure of this region is lost, leading to higher flexibility, and alteration in affinities due to binding to alternate sites on Cdh1. Our findings identify roles for the anchoring residues in the non-canonical ABBA-like motif to promote binding to the APC/CCdh1 and regulation of CDCA3 protein levels.
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Affiliation(s)
- Tabassum Khair Barbhuiya
- Centre for Genomics and Personalised Health, and School of Chemistry and Physics, Faculty of Science, Queensland University of Technology, Brisbane, Queensland, Australia.,Cancer and Ageing Research Program, Woolloongabba, Queensland, Australia
| | - Mark Fisher
- Cancer and Ageing Research Program, Woolloongabba, Queensland, Australia.,Centre for Genomics and Personalised Health, and School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Kelvin Grove, Queensland, Australia
| | - Eric D Boittier
- Department of Chemistry, University of Basel, Basel, Switzerland
| | - Emma Bolderson
- Cancer and Ageing Research Program, Woolloongabba, Queensland, Australia.,Centre for Genomics and Personalised Health, and School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Kelvin Grove, Queensland, Australia
| | - Kenneth J O'Byrne
- Cancer and Ageing Research Program, Woolloongabba, Queensland, Australia.,Centre for Genomics and Personalised Health, and School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Kelvin Grove, Queensland, Australia
| | - Derek J Richard
- Cancer and Ageing Research Program, Woolloongabba, Queensland, Australia.,Centre for Genomics and Personalised Health, and School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Kelvin Grove, Queensland, Australia
| | - Mark Nathaniel Adams
- Cancer and Ageing Research Program, Woolloongabba, Queensland, Australia.,Centre for Genomics and Personalised Health, and School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Kelvin Grove, Queensland, Australia
| | - Neha S Gandhi
- Centre for Genomics and Personalised Health, and School of Chemistry and Physics, Faculty of Science, Queensland University of Technology, Brisbane, Queensland, Australia.,Cancer and Ageing Research Program, Woolloongabba, Queensland, Australia
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7
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Zhang S, You X, Zheng Y, Shen Y, Xiong X, Sun Y. The UBE2C/CDH1/DEPTOR axis is an oncogene and tumor suppressor cascade in lung cancer cells. J Clin Invest 2023; 133:162434. [PMID: 36548081 PMCID: PMC9927933 DOI: 10.1172/jci162434] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 12/20/2022] [Indexed: 12/24/2022] Open
Abstract
Ubiquitin-conjugating enzyme E2C (UBE2C) mediates ubiquitylation chain formation via the K11 linkage. While previous in vitro studies showed that UBE2C plays a growth-promoting role in cancer cell lines, the underlying mechanism remains elusive. Still unknown is whether and how UBE2C plays a promoting role in vivo. Here we report that UBE2C was indeed essential for growth and survival of lung cancer cells harboring Kras mutations, and UBE2C was required for KrasG12D-induced lung tumorigenesis, since Ube2c deletion significantly inhibited tumor formation and extended the lifespan of mice. Mechanistically, KrasG12D induced expression of UBE2C, which coupled with APC/CCDH1 E3 ligase to promote ubiquitylation and degradation of DEPTOR, leading to activation of mTORC signaling. Importantly, DEPTOR levels fluctuated during cell cycle progression in a manner dependent on UBE2C and CDH1, indicating their physiological connection. Finally, Deptor deletion fully rescued the tumor inhibitory effect of Ube2c deletion in the KrasG12D lung tumor model, indicating a causal role of Deptor. Taken together, our study shows that the UBE2C/CDH1/DEPTOR axis forms an oncogene and tumor suppressor cascade that regulates cell cycle progression and autophagy and validates UBE2C an attractive target for lung cancer associated with Kras mutations.
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Affiliation(s)
- Shizhen Zhang
- Cancer Institute and.,Department of Breast Surgery and Oncology, Key Laboratory of Cancer Prevention and Intervention, Ministry of Education, the Second Affiliated Hospital, and
| | - Xiahong You
- Cancer Institute and.,Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Yawen Zheng
- Cancer Institute and.,Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Yanwen Shen
- Cancer Institute and.,Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiufang Xiong
- Cancer Institute and.,Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Yi Sun
- Cancer Institute and.,Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China.,Zhejiang University Cancer Center, Hangzhou, China.,Research Center for Life Science and Human Health, Binjiang Institute of Zhejiang University, Hangzhou, China
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8
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Abdelbaki A, Ascanelli C, Okoye CN, Akman HB, Janson G, Min M, Marcozzi C, Hagting A, Grant R, De Luca M, Asteriti IA, Guarguaglini G, Paiardini A, Lindon C. Revisiting degron motifs in human AURKA required for its targeting by APC/C FZR1. Life Sci Alliance 2023; 6:6/2/e202201372. [PMID: 36450448 PMCID: PMC9713472 DOI: 10.26508/lsa.202201372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Revised: 11/17/2022] [Accepted: 11/18/2022] [Indexed: 12/02/2022] Open
Abstract
Mitotic kinase Aurora A (AURKA) diverges from other kinases in its multiple active conformations that may explain its interphase roles and the limited efficacy of drugs targeting the kinase pocket. Regulation of AURKA activity by the cell is critically dependent on destruction mediated by the anaphase-promoting complex (APC/CFZR1) during mitotic exit and G1 phase and requires an atypical N-terminal degron in AURKA called the "A-box" in addition to a reported canonical D-box degron in the C-terminus. Here, we find that the reported C-terminal D-box of AURKA does not act as a degron and instead mediates essential structural features of the protein. In living cells, the N-terminal intrinsically disordered region of AURKA containing the A-box is sufficient to confer FZR1-dependent mitotic degradation. Both in silico and in cellulo assays predict the QRVL short linear interacting motif of the A-box to be a phospho-regulated D-box. We propose that degradation of full-length AURKA also depends on an intact C-terminal domain because of critical conformational parameters permissive for both activity and mitotic degradation of AURKA.
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Affiliation(s)
- Ahmed Abdelbaki
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | | | - Cynthia N Okoye
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - H Begum Akman
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Giacomo Janson
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | - Mingwei Min
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Chiara Marcozzi
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Anja Hagting
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Rhys Grant
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Maria De Luca
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Italia Anna Asteriti
- Institute of Molecular Biology and Pathology, National Research Council of Italy, c/o Sapienza University of Rome, Rome, Italy
| | - Giulia Guarguaglini
- Institute of Molecular Biology and Pathology, National Research Council of Italy, c/o Sapienza University of Rome, Rome, Italy
| | | | - Catherine Lindon
- Department of Pharmacology, University of Cambridge, Cambridge, UK
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9
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Fischer ES. Kinetochore‐catalyzed MCC
formation: A structural perspective. IUBMB Life 2022; 75:289-310. [PMID: 36518060 DOI: 10.1002/iub.2697] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 11/08/2022] [Indexed: 12/23/2022]
Abstract
The spindle assembly checkpoint (SAC) is a cellular surveillance mechanism that functions to ensure accurate chromosome segregation during mitosis. Macromolecular complexes known as kinetochores, act as the interface of sister chromatid attachment to spindle microtubules. In response to unattached kinetochores, the SAC activates its effector, the mitotic checkpoint complex (MCC), which delays mitotic exit until all sister chromatid pairs have achieved successful attachment to the bipolar mitotic spindle. Formation of the MCC (composed of Mad2, BubR1, Bub3 and Cdc20) is regulated by an Mps1 kinase-dependent phosphorylation signaling cascade which assembles and repositions components of the MCC onto a catalytic scaffold. This scaffold functions to catalyze the conversion of the HORMA-domain protein Mad2 from an "inactive" open-state (O-Mad2) into an "active" closed-Mad2 (C-Mad2), and simultaneous Cdc20 binding. Here, our current understanding of the molecular mechanisms underlying the kinetic barrier to C-Mad2:Cdc20 formation will be reviewed. Recent progress in elucidating the precise molecular choreography orchestrated by the catalytic scaffold to rapidly assemble the MCC will be examined, and unresolved questions will be highlighted. Ultimately, understanding how the SAC rapidly activates the checkpoint not only provides insights into how cells maintain genomic integrity during mitosis, but also provides a paradigm for how cells can utilize molecular switches, including other HORMA domain-containing proteins, to make rapid changes to a cell's physiological state.
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Affiliation(s)
- Elyse S. Fischer
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus Cambridge UK
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10
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STYK1/NOK affects cell cycle late mitosis and directly interacts with anaphase-promoting complex activator CDH1. Heliyon 2022; 8:e12058. [PMID: 36506394 PMCID: PMC9732331 DOI: 10.1016/j.heliyon.2022.e12058] [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: 12/14/2021] [Revised: 02/25/2022] [Accepted: 11/25/2022] [Indexed: 12/07/2022] Open
Abstract
The novel oncogene STYK1/NOK plays critical roles in cancer development. However, its regulation during cell division is less defined. In this paper, we show that over-expression of STYK1/NOK caused mitotic arrest and cytokinesis defects. The protein level of STYK/NOK fluctuated during the cell cycle, with a peak at mitosis and a quick reduction upon mitotic exit. The cell cycle-related expression pattern of STYK1/NOK resembled the one of aurora kinases and polo-like kinase 1. Depletion of APC3 led to accumulation of STYK1/NOK and to the G2/M arrest. Co-immunoprecipitation experiment demonstrated the direct interaction of STYK1/NOK with CDH1. Overexpression of CDH1 shortened the half-life of STYK1/NOK. The kinase domain, but not the five D boxes, of STYK1/NOK was responsible for the interaction with CDH1. Altogether, our data demonstrated for the first time that STYK1/NOK could affect cell division, probably by directly targeting key components of APC/C such as CDH1 at late mitosis. Current study may provide a vital mechanistic clue for understanding the roles of STYK1/NOK in mitosis and cytokinesis during STYK1NOK mediated genomic instability and oncogenesis.
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11
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Intrinsically Disordered Proteins: An Overview. Int J Mol Sci 2022; 23:ijms232214050. [PMID: 36430530 PMCID: PMC9693201 DOI: 10.3390/ijms232214050] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Revised: 11/07/2022] [Accepted: 11/08/2022] [Indexed: 11/16/2022] Open
Abstract
Many proteins and protein segments cannot attain a single stable three-dimensional structure under physiological conditions; instead, they adopt multiple interconverting conformational states. Such intrinsically disordered proteins or protein segments are highly abundant across proteomes, and are involved in various effector functions. This review focuses on different aspects of disordered proteins and disordered protein regions, which form the basis of the so-called "Disorder-function paradigm" of proteins. Additionally, various experimental approaches and computational tools used for characterizing disordered regions in proteins are discussed. Finally, the role of disordered proteins in diseases and their utility as potential drug targets are explored.
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12
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A Degradation Motif in STAU1 Defines a Novel Family of Proteins Involved in Inflammation. Int J Mol Sci 2022; 23:ijms231911588. [PMID: 36232890 PMCID: PMC9569955 DOI: 10.3390/ijms231911588] [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: 08/17/2022] [Revised: 09/24/2022] [Accepted: 09/26/2022] [Indexed: 11/21/2022] Open
Abstract
Cancer development is regulated by inflammation. Staufen1 (STAU1) is an RNA-binding protein whose expression level is critical in cancer cells as it is related to cell proliferation or cell death. STAU1 protein levels are downregulated during mitosis due to its degradation by the E3 ubiquitin ligase anaphase-promoting complex/cyclosome (APC/C). In this paper, we map the molecular determinant involved in STAU1 degradation to amino acids 38-50, and by alanine scanning, we shorten the motif to F39PxPxxLxxxxL50 (FPL-motif). Mutation of the FPL-motif prevents STAU1 degradation by APC/C. Interestingly, a search in databases reveals that the FPL-motif is shared by 15 additional proteins, most of them being involved in inflammation. We show that one of these proteins, MAP4K1, is indeed degraded via the FPL-motif; however, it is not a target of APC/C. Using proximity labeling with STAU1, we identify TRIM25, an E3 ubiquitin ligase involved in the innate immune response and interferon production, as responsible for STAU1 and MAP4K1 degradation, dependent on the FPL-motif. These results are consistent with previous studies that linked STAU1 to cancer-induced inflammation and identified a novel degradation motif that likely coordinates a novel family of proteins involved in inflammation. Data are available via ProteomeXchange with the identifier PXD036675.
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13
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Okoye CN, Rowling PJE, Itzhaki LS, Lindon C. Counting Degrons: Lessons From Multivalent Substrates for Targeted Protein Degradation. Front Physiol 2022; 13:913063. [PMID: 35860655 PMCID: PMC9289945 DOI: 10.3389/fphys.2022.913063] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 06/08/2022] [Indexed: 11/18/2022] Open
Abstract
E3s comprise a structurally diverse group of at least 800 members, most of which target multiple substrates through specific and regulated protein-protein interactions. These interactions typically rely on short linear motifs (SLiMs), called "degrons", in an intrinsically disordered region (IDR) of the substrate, with variable rules of engagement governing different E3-docking events. These rules of engagement are of importance to the field of targeted protein degradation (TPD), where substrate ubiquitination and destruction require tools to effectively harness ubiquitin ligases (E3s). Substrates are often found to contain multiple degrons, or multiple copies of a degron, contributing to the affinity and selectivity of the substrate for its E3. One important paradigm for E3-substrate docking is presented by the Anaphase-Promoting Complex/Cyclosome (APC/C), a multi-subunit E3 ligase that targets hundreds of proteins for destruction during mitotic exit. APC/C substrate targeting takes place in an ordered manner thought to depend on tightly regulated interactions of substrates, with docking sites provided by the substoichiometric APC/C substrate adaptors and coactivators, Cdc20 or Cdh1/FZR1. Both structural and functional studies of individual APC/C substrates indicate that productive ubiquitination usually requires more than one degron, and that degrons are of different types docking to distinct sites on the coactivators. However, the dynamic nature of APC/C substrate recruitment, and the influence of multiple degrons, remains poorly understood. Here we review the significance of multiple degrons in a number of E3-substrate interactions that have been studied in detail, illustrating distinct kinetic effects of multivalency and allovalency, before addressing the role of multiple degrons in APC/C substrates, key to understanding ordered substrate destruction by APC/C. Lastly, we consider how lessons learnt from these studies can be applied in the design of TPD tools.
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Affiliation(s)
| | | | | | - Catherine Lindon
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom
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14
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Lee SB, Garofano L, Ko A, D'Angelo F, Frangaj B, Sommer D, Gan Q, Kim K, Cardozo T, Iavarone A, Lasorella A. Regulated interaction of ID2 with the anaphase-promoting complex links progression through mitosis with reactivation of cell-type-specific transcription. Nat Commun 2022; 13:2089. [PMID: 35440621 PMCID: PMC9018835 DOI: 10.1038/s41467-022-29502-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 03/13/2022] [Indexed: 12/05/2022] Open
Abstract
Tissue-specific transcriptional activity is silenced in mitotic cells but it remains unclear whether the mitotic regulatory machinery interacts with tissue-specific transcriptional programs. We show that such cross-talk involves the controlled interaction between core subunits of the anaphase-promoting complex (APC) and the ID2 substrate. The N-terminus of ID2 is independently and structurally compatible with a pocket composed of core APC/C subunits that may optimally orient ID2 onto the APCCDH1 complex. Phosphorylation of serine-5 by CDK1 prevented the association of ID2 with core APC, impaired ubiquitylation and stabilized ID2 protein at the mitosis-G1 transition leading to inhibition of basic Helix-Loop-Helix (bHLH)-mediated transcription. The serine-5 phospho-mimetic mutant of ID2 that inefficiently bound core APC remained stable during mitosis, delayed exit from mitosis and reloading of bHLH transcription factors on chromatin. It also locked cells into a "mitotic stem cell" transcriptional state resembling the pluripotent program of embryonic stem cells. The substrates of APCCDH1 SKP2 and Cyclin B1 share with ID2 the phosphorylation-dependent, D-box-independent interaction with core APC. These results reveal a new layer of control of the mechanism by which substrates are recognized by APC.
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Affiliation(s)
- Sang Bae Lee
- Institute for Cancer Genetics, Columbia University Medical Center, New York, 10032, USA.
- Division of Life Sciences, Jeonbuk National University, Jeonju, 54896, Republic of Korea.
| | - Luciano Garofano
- Institute for Cancer Genetics, Columbia University Medical Center, New York, 10032, USA
| | - Aram Ko
- Institute for Cancer Genetics, Columbia University Medical Center, New York, 10032, USA
| | - Fulvio D'Angelo
- Institute for Cancer Genetics, Columbia University Medical Center, New York, 10032, USA
| | - Brulinda Frangaj
- Institute for Cancer Genetics, Columbia University Medical Center, New York, 10032, USA
| | - Danika Sommer
- Institute for Cancer Genetics, Columbia University Medical Center, New York, 10032, USA
| | - Qiwen Gan
- Institute for Cancer Genetics, Columbia University Medical Center, New York, 10032, USA
| | - KyeongJin Kim
- Department of Biomedical Sciences, College of Medicine, Inha University, Incheon, Republic of Korea
| | - Timothy Cardozo
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, NYU Langone Health, New York, NY, 10016, USA
| | - Antonio Iavarone
- Institute for Cancer Genetics, Columbia University Medical Center, New York, 10032, USA.
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, 10032, USA.
- Department of Neurology, Columbia University Medical Center, New York, 10032, USA.
- Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, 10032, USA.
| | - Anna Lasorella
- Institute for Cancer Genetics, Columbia University Medical Center, New York, 10032, USA.
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, 10032, USA.
- Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, 10032, USA.
- Department of Pediatrics, Columbia University Medical Center, New York, 10032, USA.
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15
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Elowe S, Bolanos-Garcia VM. The spindle checkpoint proteins BUB1 and BUBR1: (SLiM)ming down to the basics. Trends Biochem Sci 2022; 47:352-366. [DOI: 10.1016/j.tibs.2022.01.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 01/19/2022] [Accepted: 01/20/2022] [Indexed: 12/16/2022]
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16
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Hartooni N, Sung J, Jain A, Morgan DO. Single-molecule analysis of specificity and multivalency in binding of short linear substrate motifs to the APC/C. Nat Commun 2022; 13:341. [PMID: 35039540 PMCID: PMC8764033 DOI: 10.1038/s41467-022-28031-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 01/05/2022] [Indexed: 11/09/2022] Open
Abstract
Robust regulatory signals in the cell often depend on interactions between short linear motifs (SLiMs) and globular proteins. Many of these interactions are poorly characterized because the binding proteins cannot be produced in the amounts needed for traditional methods. To address this problem, we developed a single-molecule off-rate (SMOR) assay based on microscopy of fluorescent ligand binding to immobilized protein partners. We used it to characterize substrate binding to the Anaphase-Promoting Complex/Cyclosome (APC/C), a ubiquitin ligase that triggers chromosome segregation. We find that SLiMs in APC/C substrates (the D box and KEN box) display distinct affinities and specificities for the substrate-binding subunits of the APC/C, and we show that multiple SLiMs in a substrate generate a high-affinity multivalent interaction. The remarkably adaptable substrate-binding mechanisms of the APC/C have the potential to govern the order of substrate destruction in mitosis.
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Affiliation(s)
- Nairi Hartooni
- Department of Physiology, University of California, San Francisco, CA, 94143, USA.,Tetrad Graduate Program, University of California, San Francisco, CA, 94143, USA
| | - Jongmin Sung
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA, 94143, USA.,Howard Hughes Medical Institute, University of California, San Francisco, CA, 94143, USA.,Roche Sequencing Solutions, Santa Clara, CA, 95050, USA
| | - Ankur Jain
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA, 94143, USA.,Howard Hughes Medical Institute, University of California, San Francisco, CA, 94143, USA.,Whitehead Institute for Biomedical Research, Cambridge, MA, 02142, USA
| | - David O Morgan
- Department of Physiology, University of California, San Francisco, CA, 94143, USA. .,Tetrad Graduate Program, University of California, San Francisco, CA, 94143, USA.
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17
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Manford AG, Mena EL, Shih KY, Gee CL, McMinimy R, Martínez-González B, Sherriff R, Lew B, Zoltek M, Rodríguez-Pérez F, Woldesenbet M, Kuriyan J, Rape M. Structural basis and regulation of the reductive stress response. Cell 2021; 184:5375-5390.e16. [PMID: 34562363 PMCID: PMC8810291 DOI: 10.1016/j.cell.2021.09.002] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 06/27/2021] [Accepted: 08/31/2021] [Indexed: 12/30/2022]
Abstract
Although oxidative phosphorylation is best known for producing ATP, it also yields reactive oxygen species (ROS) as invariant byproducts. Depletion of ROS below their physiological levels, a phenomenon known as reductive stress, impedes cellular signaling and has been linked to cancer, diabetes, and cardiomyopathy. Cells alleviate reductive stress by ubiquitylating and degrading the mitochondrial gatekeeper FNIP1, yet it is unknown how the responsible E3 ligase CUL2FEM1B can bind its target based on redox state and how this is adjusted to changing cellular environments. Here, we show that CUL2FEM1B relies on zinc as a molecular glue to selectively recruit reduced FNIP1 during reductive stress. FNIP1 ubiquitylation is gated by pseudosubstrate inhibitors of the BEX family, which prevent premature FNIP1 degradation to protect cells from unwarranted ROS accumulation. FEM1B gain-of-function mutation and BEX deletion elicit similar developmental syndromes, showing that the zinc-dependent reductive stress response must be tightly regulated to maintain cellular and organismal homeostasis.
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Affiliation(s)
- Andrew G Manford
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Elijah L Mena
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Karen Y Shih
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Christine L Gee
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Rachael McMinimy
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Brenda Martínez-González
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Rumi Sherriff
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Brandon Lew
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Madeline Zoltek
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Fernando Rodríguez-Pérez
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Makda Woldesenbet
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - John Kuriyan
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California at Berkeley, Berkeley, CA 94720, USA; California Institute for Quantitative Biosciences (QB3), University of California at Berkeley, Berkeley, CA 94720, USA; Molecular Biophysics and Integrative Bio-Imaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Department of Chemistry, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Michael Rape
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California at Berkeley, Berkeley, CA 94720, USA; California Institute for Quantitative Biosciences (QB3), University of California at Berkeley, Berkeley, CA 94720, USA.
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18
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Lara-Gonzalez P, Pines J, Desai A. Spindle assembly checkpoint activation and silencing at kinetochores. Semin Cell Dev Biol 2021; 117:86-98. [PMID: 34210579 PMCID: PMC8406419 DOI: 10.1016/j.semcdb.2021.06.009] [Citation(s) in RCA: 103] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/17/2021] [Accepted: 06/17/2021] [Indexed: 01/01/2023]
Abstract
The spindle assembly checkpoint (SAC) is a surveillance mechanism that promotes accurate chromosome segregation in mitosis. The checkpoint senses the attachment state of kinetochores, the proteinaceous structures that assemble onto chromosomes in mitosis in order to mediate their interaction with spindle microtubules. When unattached, kinetochores generate a diffusible inhibitor that blocks the activity of the anaphase-promoting complex/cyclosome (APC/C), an E3 ubiquitin ligase required for sister chromatid separation and exit from mitosis. Work from the past decade has greatly illuminated our understanding of the mechanisms by which the diffusible inhibitor is assembled and how it inhibits the APC/C. However, less is understood about how SAC proteins are recruited to kinetochores in the absence of microtubule attachment, how the kinetochore catalyzes formation of the diffusible inhibitor, and how attachments silence the SAC at the kinetochore. Here, we summarize current understanding of the mechanisms that activate and silence the SAC at kinetochores and highlight open questions for future investigation.
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Affiliation(s)
- Pablo Lara-Gonzalez
- Ludwig Institute for Cancer Research, USA; Department of Cellular & Molecular Medicine, University of California San Diego, La Jolla, CA 92093, USA.
| | | | - Arshad Desai
- Ludwig Institute for Cancer Research, USA; Department of Cellular & Molecular Medicine, University of California San Diego, La Jolla, CA 92093, USA.
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19
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Thomas C, Wetherall B, Levasseur MD, Harris RJ, Kerridge ST, Higgins JMG, Davies OR, Madgwick S. A prometaphase mechanism of securin destruction is essential for meiotic progression in mouse oocytes. Nat Commun 2021; 12:4322. [PMID: 34262048 PMCID: PMC8280194 DOI: 10.1038/s41467-021-24554-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 06/24/2021] [Indexed: 11/10/2022] Open
Abstract
Successful cell division relies on the timely removal of key cell cycle proteins such as securin. Securin inhibits separase, which cleaves the cohesin rings holding chromosomes together. Securin must be depleted before anaphase to ensure chromosome segregation occurs with anaphase. Here we find that in meiosis I, mouse oocytes contain an excess of securin over separase. We reveal a mechanism that promotes excess securin destruction in prometaphase I. Importantly, this mechanism relies on two phenylalanine residues within the separase-interacting segment (SIS) of securin that are only exposed when securin is not bound to separase. We suggest that these residues facilitate the removal of non-separase-bound securin ahead of metaphase, as inhibiting this period of destruction by mutating both residues causes the majority of oocytes to arrest in meiosis I. We further propose that cellular securin levels exceed the amount an oocyte is capable of removing in metaphase alone, such that the prometaphase destruction mechanism identified here is essential for correct meiotic progression in mouse oocytes.
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Affiliation(s)
- Christopher Thomas
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK. .,Max Planck Institute for Biophysical Chemistry, Gottingen, Germany.
| | - Benjamin Wetherall
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Mark D Levasseur
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Rebecca J Harris
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Scott T Kerridge
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Jonathan M G Higgins
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Owen R Davies
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK.,Institute of Cell Biology, University of Edinburgh, Michael Swann Building, Max Born Crescent, Edinburgh, UK
| | - Suzanne Madgwick
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK.
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20
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Fukumoto Y, Ikeuchi M, Qu L, Hoshino T, Yamaguchi N, Nakayama Y, Ogra Y. Nuclear translocation promotes proteasomal degradation of human Rad17 protein through the N-terminal destruction boxes. J Biol Chem 2021; 297:100831. [PMID: 34174284 PMCID: PMC8318897 DOI: 10.1016/j.jbc.2021.100831] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/17/2021] [Accepted: 05/24/2021] [Indexed: 12/15/2022] Open
Abstract
The ATR pathway is one of the major DNA damage checkpoints, and Rad17 is a DNA-binding protein that is phosphorylated upon DNA damage by ATR kinase. Rad17 recruits the 9-1-1 complex that mediates the checkpoint activation, and proteasomal degradation of Rad17 is important for recovery from the ATR pathway. Here, we identified several Rad17 mutants deficient in nuclear localization and resistant to proteasomal degradation. The nuclear localization signal was identified in the central basic domain of Rad17. Rad17 Δ230–270 and R240A/L243A mutants that were previously postulated to lack the destruction box, a sequence that is recognized by the ubiquitin ligase/anaphase-promoting complex that mediates degradation of Rad17, also showed cytoplasmic localization. Our data indicate that the nuclear translocation of Rad17 is functionally linked to the proteasomal degradation. The ATP-binding activity of Rad17, but not hydrolysis, is essential for the nuclear translocation, and the ATPase domain orchestrates the nuclear translocation, the proteasomal degradation, as well as the interaction with the 9-1-1 complex. The Rad17 mutant that lacked a nuclear localization signal was proficient in the interaction with the 9-1-1 complex, suggesting cytosolic association of Rad17 and the 9-1-1 complex. Finally, we identified two tandem canonical and noncanonical destruction boxes in the N-terminus of Rad17 as the bona fide destruction box, supporting the role of anaphase-promoting complex in the degradation of Rad17. We propose a model in which Rad17 is activated in the cytoplasm for translocation into the nucleus and continuously degraded in the nucleus even in the absence of exogenous DNA damage.
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Affiliation(s)
- Yasunori Fukumoto
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan.
| | - Masayoshi Ikeuchi
- Department of Biochemistry & Molecular Biology, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Liang Qu
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
| | - Tyuji Hoshino
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
| | - Naoto Yamaguchi
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
| | - Yuji Nakayama
- Department of Biochemistry & Molecular Biology, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Yasumitsu Ogra
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
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21
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Koliopoulos MG, Alfieri C. Cell cycle regulation by complex nanomachines. FEBS J 2021; 289:5100-5120. [PMID: 34143558 DOI: 10.1111/febs.16082] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 05/05/2021] [Accepted: 05/17/2021] [Indexed: 12/13/2022]
Abstract
The cell cycle is the essential biological process where one cell replicates its genome and segregates the resulting two copies into the daughter cells during mitosis. Several aspects of this process have fascinated humans since the nineteenth century. Today, the cell cycle is exhaustively investigated because of its profound connections with human diseases and cancer. At the heart of the molecular network controlling the cell cycle, we find the cyclin-dependent kinases (CDKs) acting as an oscillator to impose an orderly and highly regulated progression through the different cell cycle phases. This oscillator integrates both internal and external signals via a multitude of signalling pathways involving posttranslational modifications including phosphorylation, protein ubiquitination and mechanisms of transcriptional regulation. These tasks are specifically performed by multi-subunit complexes, which are intensively studied both biochemically and structurally with the aim to unveil mechanistic insights into their molecular function. The scope of this review is to summarise the structural biology of the cell cycle machinery, with specific focus on the core cell cycle machinery involving the CDK-cyclin oscillator. We highlight the contribution of cryo-electron microscopy, which has started to revolutionise our understanding of the molecular function and dynamics of the key players of the cell cycle.
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Affiliation(s)
- Marios G Koliopoulos
- Chester Beatty Laboratories, Structural Biology Division, Institute of Cancer Research, London, UK
| | - Claudio Alfieri
- Chester Beatty Laboratories, Structural Biology Division, Institute of Cancer Research, London, UK
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22
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Zhang S, Shen Y, Li H, Bi C, Sun Y, Xiong X, Wei W, Sun Y. The Negative Cross-Talk between SAG/RBX2/ROC2 and APC/C E3 Ligases in Regulation of Cell Cycle Progression and Drug Resistance. Cell Rep 2021; 32:108102. [PMID: 32905768 PMCID: PMC7505520 DOI: 10.1016/j.celrep.2020.108102] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 07/05/2020] [Accepted: 08/11/2020] [Indexed: 01/08/2023] Open
Abstract
Anaphase-promoting complex/cyclosome (APC/C) is a well-characterized E3 ligase that couples with UBE2C and UBE2S E2s for substrate ubiquitylation by the K11 linkage. Our recent data show that SAG/RBX2/ROC2, a RING component of Cullin-RING E3 ligase, also complexes with these E2s for K11-linked substrate polyubiquitylation. Whether these two E3s cross-talk with each other was previously unknown. Here, we report that SAG competes with APC2 for UBE2C/UBE2S binding to act as a potential endogenous inhibitor of APC/C, thereby regulating the G2-to-M progression. As such, SAG knockdown triggers premature activation of APC/C, leading to mitotic slippage and resistance to anti-microtubule drugs. On the other hand, SAG itself is a substrate of APC/CCDH1 for targeted degradation at the G1 phase. The degradation-resistant mutant of SAG-R98A/L101A accelerates the G1-to-S progression. Our study reveals that the negative cross-talk between SAG and APC/C is likely a mechanism to ensure the fidelity of cell cycle progression. Zhang et al. provide a mechanistic insight of how negative cross-talk between E3 ligases SAG and APC/C ensures proper cell cycle progression. SAG knockdown prematurely activates APC/C to promote mitotic progression and trigger anti-microtubule drugs resistance, whereas SAG degradation by APC/CCDH1 mainly occurs in G1 phase for proper G1-to-S transition.
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Affiliation(s)
- Shizhen Zhang
- Cancer Institute of the Second Affiliated Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310029, China
| | - Yanwen Shen
- Cancer Institute of the Second Affiliated Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310029, China
| | - Hua Li
- Division of Radiation and Cancer Biology, Department of Radiation Oncology, University of Michigan, 4424B MS-1, 1301 Catherine Street, Ann Arbor, MI 48109, USA
| | - Chao Bi
- Cancer Institute of the Second Affiliated Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310029, China
| | - Yilun Sun
- Division of Radiation and Cancer Biology, Department of Radiation Oncology, University of Michigan, 4424B MS-1, 1301 Catherine Street, Ann Arbor, MI 48109, USA
| | - Xiufang Xiong
- Cancer Institute of the Second Affiliated Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310029, China
| | - Wenyi Wei
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Yi Sun
- Cancer Institute of the Second Affiliated Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310029, China.
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Elevating CDCA3 levels in non-small cell lung cancer enhances sensitivity to platinum-based chemotherapy. Commun Biol 2021; 4:638. [PMID: 34050247 PMCID: PMC8163776 DOI: 10.1038/s42003-021-02136-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Accepted: 04/19/2021] [Indexed: 12/14/2022] Open
Abstract
Platinum-based chemotherapy remains the cornerstone of treatment for most non-small cell lung cancer (NSCLC) cases either as maintenance therapy or in combination with immunotherapy. However, resistance remains a primary issue. Our findings point to the possibility of exploiting levels of cell division cycle associated protein-3 (CDCA3) to improve response of NSCLC tumours to therapy. We demonstrate that in patients and in vitro analyses, CDCA3 levels correlate with measures of genome instability and platinum sensitivity, whereby CDCA3high tumours are sensitive to cisplatin and carboplatin. In NSCLC, CDCA3 protein levels are regulated by the ubiquitin ligase APC/C and cofactor Cdh1. Here, we identified that the degradation of CDCA3 is modulated by activity of casein kinase 2 (CK2) which promotes an interaction between CDCA3 and Cdh1. Supporting this, pharmacological inhibition of CK2 with CX-4945 disrupts CDCA3 degradation, elevating CDCA3 levels and increasing sensitivity to platinum agents. We propose that combining CK2 inhibitors with platinum-based chemotherapy could enhance platinum efficacy in CDCA3low NSCLC tumours and benefit patients. Kildey et al find that high levels of mitotic regulator CDCA3 correlates with sensitivity to platinum agents in non-small cell lung cancer patients and cell lines. They show that interfering with CDCA3 degradation through CK2 inhibition enhances CDCA3 levels and increases sensitivity to platinum agents suggesting a therapeutic route.
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24
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Ortolano NA, Romero-Morales AI, Rasmussen ML, Bodnya C, Kline LA, Joshi P, Connelly JP, Rose KL, Pruett-Miller SM, Gama V. A proteomics approach for the identification of cullin-9 (CUL9) related signaling pathways in induced pluripotent stem cell models. PLoS One 2021; 16:e0248000. [PMID: 33705438 PMCID: PMC7951927 DOI: 10.1371/journal.pone.0248000] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 02/17/2021] [Indexed: 12/13/2022] Open
Abstract
CUL9 is a non-canonical and poorly characterized member of the largest family of E3 ubiquitin ligases known as the Cullin RING ligases (CRLs). Most CRLs play a critical role in developmental processes, however, the role of CUL9 in neuronal development remains elusive. We determined that deletion or depletion of CUL9 protein causes aberrant formation of neural rosettes, an in vitro model of early neuralization. In this study, we applied mass spectrometric approaches in human pluripotent stem cells (hPSCs) and neural progenitor cells (hNPCs) to identify CUL9 related signaling pathways that may contribute to this phenotype. Through LC-MS/MS analysis of immunoprecipitated endogenous CUL9, we identified several subunits of the APC/C, a major cell cycle regulator, as potential CUL9 interacting proteins. Knockdown of the APC/C adapter protein FZR1 resulted in a significant increase in CUL9 protein levels, however, CUL9 does not appear to affect protein abundance of APC/C subunits and adapters or alter cell cycle progression. Quantitative proteomic analysis of CUL9 KO hPSCs and hNPCs identified protein networks related to metabolic, ubiquitin degradation, and transcriptional regulation pathways that are disrupted by CUL9 deletion in both hPSCs. No significant changes in oxygen consumption rates or ATP production were detected in either cell type. The results of our study build on current evidence that CUL9 may have unique functions in different cell types and that compensatory mechanisms may contribute to the difficulty of identifying CUL9 substrates.
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Affiliation(s)
- Natalya A. Ortolano
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Alejandra I. Romero-Morales
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Megan L. Rasmussen
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Caroline Bodnya
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Leigh A. Kline
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Piyush Joshi
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Jon P. Connelly
- Department of Cell & Molecular Biology, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
- Center for Advanced Genome Engineering, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Kristie L. Rose
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, United States of America
- Vanderbilt MSRC Proteomics Core, Nashville, Tennessee, United States of America
| | - Shondra M. Pruett-Miller
- Department of Cell & Molecular Biology, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
- Center for Advanced Genome Engineering, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Vivian Gama
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Vanderbilt Center for Stem Cell Biology, Nashville, Tennessee, United States of America
- Vanderbilt Brain Institute, Nashville, Tennessee, United States of America
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25
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In silico APC/C substrate discovery reveals cell cycle-dependent degradation of UHRF1 and other chromatin regulators. PLoS Biol 2020; 18:e3000975. [PMID: 33306668 PMCID: PMC7758050 DOI: 10.1371/journal.pbio.3000975] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 12/23/2020] [Accepted: 11/05/2020] [Indexed: 01/07/2023] Open
Abstract
The anaphase-promoting complex/cyclosome (APC/C) is an E3 ubiquitin ligase and critical regulator of cell cycle progression. Despite its vital role, it has remained challenging to globally map APC/C substrates. By combining orthogonal features of known substrates, we predicted APC/C substrates in silico. This analysis identified many known substrates and suggested numerous candidates. Unexpectedly, chromatin regulatory proteins are enriched among putative substrates, and we show experimentally that several chromatin proteins bind APC/C, oscillate during the cell cycle, and are degraded following APC/C activation, consistent with being direct APC/C substrates. Additional analysis revealed detailed mechanisms of ubiquitylation for UHRF1, a key chromatin regulator involved in histone ubiquitylation and DNA methylation maintenance. Disrupting UHRF1 degradation at mitotic exit accelerates G1-phase cell cycle progression and perturbs global DNA methylation patterning in the genome. We conclude that APC/C coordinates crosstalk between cell cycle and chromatin regulatory proteins. This has potential consequences in normal cell physiology, where the chromatin environment changes depending on proliferative state, as well as in disease.
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26
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Tatum NJ, Endicott JA. Chatterboxes: the structural and functional diversity of cyclins. Semin Cell Dev Biol 2020; 107:4-20. [PMID: 32414682 DOI: 10.1016/j.semcdb.2020.04.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 04/28/2020] [Accepted: 04/29/2020] [Indexed: 12/16/2022]
Abstract
Proteins of the cyclin family have divergent sequences and execute diverse roles within the cell while sharing a common fold: the cyclin box domain. Structural studies of cyclins have played a key role in our characterization and understanding of cellular processes that they control, though to date only ten of the 29 CDK-activating cyclins have been structurally characterized by X-ray crystallography or cryo-electron microscopy with or without their cognate kinases. In this review, we survey the available structures of human cyclins, highlighting their molecular features in the context of their cellular roles. We pay particular attention to how cyclin activity is regulated through fine control of degradation motif recognition and ubiquitination. Finally, we discuss the emergent roles of cyclins independent of their roles as cyclin-dependent protein kinase activators, demonstrating the cyclin box domain to be a versatile and generalized scaffolding domain for protein-protein interactions across the cellular machinery.
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Affiliation(s)
- Natalie J Tatum
- Cancer Research UK Newcastle Drug Discovery Unit, Newcastle Centre for Cancer, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Jane A Endicott
- Cancer Research UK Newcastle Drug Discovery Unit, Newcastle Centre for Cancer, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom.
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27
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Chen A, Bai L, Zhong K, Shu X, Wang A, Xiao Y, Zhang K, Shen C. APC2
CDH1
negatively regulates agrin signaling by promoting the ubiquitination and proteolytic degradation of DOK7. FASEB J 2020; 34:12009-12023. [PMID: 32687671 DOI: 10.1096/fj.202000485r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 06/24/2020] [Accepted: 06/25/2020] [Indexed: 01/28/2023]
Affiliation(s)
- Aizhong Chen
- The First Affiliated Hospital Institute of Translational Medicine School of Medicine Zhejiang University Zhejiang China
| | - Lei Bai
- The First Affiliated Hospital Institute of Translational Medicine School of Medicine Zhejiang University Zhejiang China
| | - Keke Zhong
- The First Affiliated Hospital Institute of Translational Medicine School of Medicine Zhejiang University Zhejiang China
| | - Xiaoqiu Shu
- The First Affiliated Hospital Institute of Translational Medicine School of Medicine Zhejiang University Zhejiang China
| | - Ailian Wang
- The First Affiliated Hospital Institute of Translational Medicine School of Medicine Zhejiang University Zhejiang China
| | - Yatao Xiao
- The First Affiliated Hospital Institute of Translational Medicine School of Medicine Zhejiang University Zhejiang China
| | - Kejing Zhang
- The First Affiliated Hospital Institute of Translational Medicine School of Medicine Zhejiang University Zhejiang China
| | - Chengyong Shen
- The First Affiliated Hospital Institute of Translational Medicine School of Medicine Zhejiang University Zhejiang China
- Department of Neurobiology Key Laboratory of Medical Neurobiology of Zhejiang Province School of Medicine Zhejiang University Zhejiang China
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28
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Abstract
The nucleus is enclosed by a double-membrane structure, the nuclear envelope, which separates the nucleoplasm from the cytoplasm. The outer nuclear membrane is continuous with the endoplasmic reticulum (ER), whereas the inner nuclear membrane (INM) is a specialized compartment with a unique proteome. In order to ensure compartmental homeostasis, INM-associated degradation (INMAD) is required for both protein quality control and regulated proteolysis of INM proteins. INMAD shares similarities with ER-associated degradation (ERAD). The mechanism of ERAD is well characterized, whereas the INMAD pathway requires further definition. Here we review the three different branches of INMAD, mediated by their respective E3 ubiquitin ligases: Doa10, Asi1-3, and APC/C. We clarify the distinction between ERAD and INMAD, their substrate recognition signals, and the subsequent processing by their respective degradation machineries. We also discuss the significance of cell-cycle and developmental regulation of protein clearance at the INM, and its relationship to human disease.
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Affiliation(s)
- Bailey Koch
- a Department of Biological Science, The Florida State University , Tallahassee , FL , USA
| | - Hong-Guo Yu
- a Department of Biological Science, The Florida State University , Tallahassee , FL , USA
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29
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Huang W, Ray P, Ji W, Wang Z, Nancarrow D, Chen G, Galbán S, Lawrence TS, Beer DG, Rehemtulla A, Ramnath N, Ray D. The cytochrome P450 enzyme CYP24A1 increases proliferation of mutant KRAS-dependent lung adenocarcinoma independent of its catalytic activity. J Biol Chem 2020; 295:5906-5917. [PMID: 32165494 DOI: 10.1074/jbc.ra119.011869] [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: 11/12/2019] [Revised: 03/05/2020] [Indexed: 11/06/2022] Open
Abstract
We previously reported that overexpression of cytochrome P450 family 24 subfamily A member 1 (CYP24A1) increases lung cancer cell proliferation by activating RAS signaling and that CYP24A1 knockdown inhibits tumor growth. However, the mechanism of CYP24A1-mediated cancer cell proliferation remains unclear. Here, we conducted cell synchronization and biochemical experiments in lung adenocarcinoma cells, revealing a link between CYP24A1 and anaphase-promoting complex (APC), a key cell cycle regulator. We demonstrate that CYP24A1 expression is cell cycle-dependent; it was higher in the G2-M phase and diminished upon G1 entry. CYP24A1 has a functional destruction box (D-box) motif that allows binding with two APC adaptors, CDC20-homologue 1 (CDH1) and cell division cycle 20 (CDC20). Unlike other APC substrates, however, CYP24A1 acted as a pseudo-substrate, inhibiting CDH1 activity and promoting mitotic progression. Conversely, overexpression of a CYP24A1 D-box mutant compromised CDH1 binding, allowing CDH1 hyperactivation, thereby hastening degradation of its substrates cyclin B1 and CDC20, and accumulation of the CDC20 substrate p21, prolonging mitotic exit. These activities also occurred with a CYP24A1 isoform 2 lacking the catalytic cysteine (Cys-462), suggesting that CYP24A1's oncogenic potential is independent of its catalytic activity. CYP24A1 degradation reduced clonogenic survival of mutant KRAS-driven lung cancer cells, and calcitriol treatment increased CYP24A1 levels and tumor burden in Lsl-KRASG12D mice. These results disclose a catalytic activity-independent growth-promoting role of CYP24A1 in mutant KRAS-driven lung cancer. This suggests that CYP24A1 could be therapeutically targeted in lung cancers in which its expression is high.
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Affiliation(s)
- Wei Huang
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Paramita Ray
- Department of Radiation Oncology, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Wenbin Ji
- Department of Radiation Oncology, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Zhuwen Wang
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Derek Nancarrow
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Guoan Chen
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Stefanie Galbán
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Theodore S Lawrence
- Department of Radiation Oncology, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - David G Beer
- Department of Radiation Oncology, University of Michigan Medical School, Ann Arbor, Michigan 48109; Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Alnawaz Rehemtulla
- Department of Radiation Oncology, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Nithya Ramnath
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan 48109; Veterans Administration, Ann Arbor Healthcare System, Ann Arbor, Michigan 48105.
| | - Dipankar Ray
- Department of Radiation Oncology, University of Michigan Medical School, Ann Arbor, Michigan 48109.
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30
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APC/C ubiquitin ligase: Functions and mechanisms in tumorigenesis. Semin Cancer Biol 2020; 67:80-91. [PMID: 32165320 DOI: 10.1016/j.semcancer.2020.03.001] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 02/24/2020] [Accepted: 03/02/2020] [Indexed: 12/18/2022]
Abstract
The anaphase promoting complex/ cyclosome (APC/C), is an evolutionarily conserved protein complex essential for cellular division due to its role in regulating the mitotic transition from metaphase to anaphase. In this review, we highlight recent work that has shed light on our understanding of the role of APC/C coactivators, Cdh1 and Cdc20, in cancer initiation and development. We summarize the current state of knowledge regarding APC/C structure and function, as well as the distinct ways Cdh1 and Cdc20 are dysregulated in human cancer. We also discuss APC/C inhibitors, novel approaches for targeting the APC/C as a cancer therapy, and areas for future work.
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31
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Manzione MG, Rombouts J, Steklov M, Pasquali L, Sablina A, Gelens L, Qian J, Bollen M. Co-regulation of the antagonistic RepoMan:Aurora-B pair in proliferating cells. Mol Biol Cell 2020; 31:419-438. [PMID: 31967936 PMCID: PMC7185888 DOI: 10.1091/mbc.e19-12-0698] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Chromosome segregation during mitosis is antagonistically regulated by the Aurora-B kinase and RepoMan (recruits PP1 onto mitotic chromatin at anaphase)-associated phosphatases PP1/PP2A. Aurora B is overexpressed in many cancers but, surprisingly, this only rarely causes lethal aneuploidy. Here we show that RepoMan abundance is regulated by the same mechanisms that control Aurora B, including FOXM1-regulated expression and proteasomal degradation following ubiquitination by APC/C-CDH1 or SCFFBXW7. The deregulation of these mechanisms can account for the balanced co-overexpression of Aurora B and RepoMan in many cancers, which limits chromosome segregation errors. In addition, Aurora B and RepoMan independently promote cancer cell proliferation by reducing checkpoint-induced cell-cycle arrest during interphase. The co–up-regulation of RepoMan and Aurora B in tumors is inversely correlated with patient survival, underscoring its potential importance for tumor progression. Finally, we demonstrate that high RepoMan levels sensitize cancer cells to Aurora-B inhibitors. Hence, the co–up-regulation of RepoMan and Aurora B is associated with tumor aggressiveness but also exposes a vulnerable target for therapeutic intervention.
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Affiliation(s)
| | - Jan Rombouts
- Laboratory of Dynamics in Biological Systems, Department of Cellular and Molecular Medicine, KU Leuven, B-3000 Leuven, Belgium
| | - Mikhail Steklov
- VIB-KU Leuven Center for Cancer Biology, VIB, 3000 Leuven, Belgium
| | - Lorenzo Pasquali
- Dermatology and Venereology Section, Department of Medicine Solna, Karolinska Institutet, SE-17176 Stockholm, Sweden
| | - Anna Sablina
- Department of Oncology, KU Leuven, B-3000 Leuven, Belgium.,VIB-KU Leuven Center for Cancer Biology, VIB, 3000 Leuven, Belgium
| | - Lendert Gelens
- Laboratory of Dynamics in Biological Systems, Department of Cellular and Molecular Medicine, KU Leuven, B-3000 Leuven, Belgium
| | - Junbin Qian
- Laboratory of Biosignaling & Therapeutics, KU Leuven, B-3000 Leuven, Belgium.,Laboratory for Translational Genetics, Department of Human Genetics, KU Leuven, B-3000 Leuven, Belgium.,VIB-KU Leuven Center for Cancer Biology, VIB, 3000 Leuven, Belgium
| | - Mathieu Bollen
- Laboratory of Biosignaling & Therapeutics, KU Leuven, B-3000 Leuven, Belgium
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32
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Palopoli N, Iserte JA, Chemes LB, Marino-Buslje C, Parisi G, Gibson TJ, Davey NE. The articles.ELM resource: simplifying access to protein linear motif literature by annotation, text-mining and classification. Database (Oxford) 2020; 2020:baaa040. [PMID: 32507889 PMCID: PMC7276420 DOI: 10.1093/database/baaa040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 04/24/2020] [Accepted: 05/06/2020] [Indexed: 11/12/2022]
Abstract
Modern biology produces data at a staggering rate. Yet, much of these biological data is still isolated in the text, figures, tables and supplementary materials of articles. As a result, biological information created at great expense is significantly underutilised. The protein motif biology field does not have sufficient resources to curate the corpus of motif-related literature and, to date, only a fraction of the available articles have been curated. In this study, we develop a set of tools and a web resource, 'articles.ELM', to rapidly identify the motif literature articles pertinent to a researcher's interest. At the core of the resource is a manually curated set of about 8000 motif-related articles. These articles are automatically annotated with a range of relevant biological data allowing in-depth search functionality. Machine-learning article classification is used to group articles based on their similarity to manually curated motif classes in the Eukaryotic Linear Motif resource. Articles can also be manually classified within the resource. The 'articles.ELM' resource permits the rapid and accurate discovery of relevant motif articles thereby improving the visibility of motif literature and simplifying the recovery of valuable biological insights sequestered within scientific articles. Consequently, this web resource removes a critical bottleneck in scientific productivity for the motif biology field. Database URL: http://slim.icr.ac.uk/articles/.
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Affiliation(s)
- N Palopoli
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, CONICET, Roque Saenz Peña 352, Bernal, Buenos Aires B1876BXD, Argentina
| | - J A Iserte
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires, CONICET, Av. Patricias Argentinas 435, Ciudad de Buenos Aires C1405BWE, Argentina
| | - L B Chemes
- Instituto de Investigaciones Biotecnológicas, Universidad Nacional de General San Martín, IIB-INTECH-CONICET, Av. 25 de Mayo y Francia, San Martín, Buenos Aires B1650, Argentina
| | - C Marino-Buslje
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires, CONICET, Av. Patricias Argentinas 435, Ciudad de Buenos Aires C1405BWE, Argentina
| | - G Parisi
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, CONICET, Roque Saenz Peña 352, Bernal, Buenos Aires B1876BXD, Argentina
| | - T J Gibson
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstraße 1, Heidelberg 69117, Germany
| | - N E Davey
- Division of Cancer Biology, The Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK
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33
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Bansal S, Tiwari S. Mechanisms for the temporal regulation of substrate ubiquitination by the anaphase-promoting complex/cyclosome. Cell Div 2019; 14:14. [PMID: 31889987 PMCID: PMC6927175 DOI: 10.1186/s13008-019-0057-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 12/04/2019] [Indexed: 12/16/2022] Open
Abstract
The anaphase-promoting complex/cyclosome (APC/C) is a multi-subunit, multifunctional ubiquitin ligase that controls the temporal degradation of numerous cell cycle regulatory proteins to direct the unidirectional cell cycle phases. Several different mechanisms contribute to ensure the correct order of substrate modification by the APC/C complex. Recent advances in biochemical, biophysical and structural studies of APC/C have provided a deep mechanistic insight into the working of this complex ubiquitin ligase. This complex displays remarkable conformational flexibility in response to various binding partners and post-translational modifications, which together regulate substrate selection and catalysis of APC/C. Apart from this, various features and modifications of the substrates also influence their recognition and affinity to APC/C complex. Ultimately, temporal degradation of substrates depends on the kind of ubiquitin modification received, the processivity of APC/C, and other extrinsic mechanisms. This review discusses our current understanding of various intrinsic and extrinsic mechanisms responsible for 'substrate ordering' by the APC/C complex.
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Affiliation(s)
- Shivangee Bansal
- School of Biotechnology, Jawaharlal Nehru University, New Delhi, 110067 India
| | - Swati Tiwari
- School of Biotechnology, Jawaharlal Nehru University, New Delhi, 110067 India
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34
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Mizrak A, Morgan DO. Polyanions provide selective control of APC/C interactions with the activator subunit. Nat Commun 2019; 10:5807. [PMID: 31862931 PMCID: PMC6925294 DOI: 10.1038/s41467-019-13864-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 12/04/2019] [Indexed: 01/18/2023] Open
Abstract
Transient interactions between the anaphase-promoting complex/cyclosome (APC/C) and its activator subunit Cdc20 or Cdh1 generate oscillations in ubiquitylation activity necessary to maintain the order of cell cycle events. Activator binds the APC/C with high affinity and exhibits negligible dissociation kinetics in vitro, and it is not clear how the rapid turnover of APC/C-activator complexes is achieved in vivo. Here, we describe a mechanism that controls APC/C-activator interactions based on the availability of substrates. We find that APC/C-activator dissociation is stimulated by abundant cellular polyanions such as nucleic acids and polyphosphate. Polyanions also interfere with substrate ubiquitylation. However, engagement with high-affinity substrate blocks the inhibitory effects of polyanions on activator binding and APC/C activity. We propose that this mechanism amplifies the effects of substrate affinity on APC/C function, stimulating processive ubiquitylation of high-affinity substrates and suppressing ubiquitylation of low-affinity substrates.
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Affiliation(s)
- Arda Mizrak
- Department of Physiology, University of California, San Francisco, CA, 94143, USA
| | - David O Morgan
- Department of Physiology, University of California, San Francisco, CA, 94143, USA.
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35
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Chen Q, Wan X, Chen Y, Liu C, Gu M, Wang Z. SGO1 induces proliferation and metastasis of prostate cancer through AKT-mediated signaling pathway. Am J Cancer Res 2019; 9:2693-2705. [PMID: 31911855 PMCID: PMC6943359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Accepted: 10/09/2018] [Indexed: 06/10/2023] Open
Abstract
Although studies have revealed some of the pathological causes associated with prostate cancer progression, further studies are still needed. Shugoshin 1 (SGO1) is a protein essential for precise chromosome segregation during mitosis and meiosis. However, the role and mechanism of SGO1 in tumors and even prostate cancer is not completely clear. In this study, expression of SGO1 in human prostate tumors were higher than that of adjacent normal tissues and were positively correlated with the poor prognosis of prostate cancer patients. SGO1 expression levels are also higher in several prostate cancer cell lines. In cell experiments, knockdown of SGO1 reduced cell proliferation, migration, and invasion in vitro and in vivo, and also inhibited cell cycle progression of prostate cancer cells. In contrast, ectopic expression of SGO1 has the opposite effects. In addition, knockdown of SGO1 induces apoptosis in prostate cancer cells by promoting cleaved caspase-3, caspase-9, and PARP. Importantly SGO1 function is dependent on AKT. Inhibition of AKT activity by AKT inhibitor abolished the role of SGO1 overexpression in promoting cell proliferation and metastasis. Therefore, SGO1 promotes the proliferation and metastasis of prostate cancer through the AKT pathway, and can be considered as an effective candidate for developing an effective prostate cancer treatment strategy.
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Affiliation(s)
- Qi Chen
- Department of Urology, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China
| | - Xiang Wan
- Department of Urology, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China
| | - Yanbo Chen
- Department of Urology, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China
| | - Chong Liu
- Department of Urology, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China
| | - Meng Gu
- Department of Urology, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China
| | - Zhong Wang
- Department of Urology, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China
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36
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Sequence and Structure Properties Uncover the Natural Classification of Protein Complexes Formed by Intrinsically Disordered Proteins via Mutual Synergistic Folding. Int J Mol Sci 2019; 20:ijms20215460. [PMID: 31683980 PMCID: PMC6862064 DOI: 10.3390/ijms20215460] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 10/28/2019] [Accepted: 10/30/2019] [Indexed: 12/17/2022] Open
Abstract
Intrinsically disordered proteins mediate crucial biological functions through their interactions with other proteins. Mutual synergistic folding (MSF) occurs when all interacting proteins are disordered, folding into a stable structure in the course of the complex formation. In these cases, the folding and binding processes occur in parallel, lending the resulting structures uniquely heterogeneous features. Currently there are no dedicated classification approaches that take into account the particular biological and biophysical properties of MSF complexes. Here, we present a scalable clustering-based classification scheme, built on redundancy-filtered features that describe the sequence and structure properties of the complexes and the role of the interaction, which is directly responsible for structure formation. Using this approach, we define six major types of MSF complexes, corresponding to biologically meaningful groups. Hence, the presented method also shows that differences in binding strength, subcellular localization, and regulation are encoded in the sequence and structural properties of proteins. While current protein structure classification methods can also handle complex structures, we show that the developed scheme is fundamentally different, and since it takes into account defining features of MSF complexes, it serves as a better representation of structures arising through this specific interaction mode.
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Qin L, Mizrak A, Guimarães DSPSF, Tambrin HM, Morgan DO, Hall MC. The pseudosubstrate inhibitor Acm1 inhibits the anaphase-promoting complex/cyclosome by combining high-affinity activator binding with disruption of Doc1/Apc10 function. J Biol Chem 2019; 294:17249-17261. [PMID: 31562243 DOI: 10.1074/jbc.ra119.009468] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 09/11/2019] [Indexed: 11/06/2022] Open
Abstract
The anaphase-promoting complex/cyclosome (APC/C) is a large, multisubunit ubiquitin ligase involved in regulation of cell division. APC/C substrate specificity arises from binding of short degron motifs in its substrates to transient activator subunits, Cdc20 and Cdh1. The destruction box (D-box) is the most common APC/C degron and plays a crucial role in substrate degradation by linking the activator to the Doc1/Apc10 subunit of core APC/C to stabilize the active holoenzyme and promote processive ubiquitylation. Degrons are also employed as pseudosubstrate motifs by APC/C inhibitors, and pseudosubstrates must bind their cognate activators tightly to outcompete substrate binding while blocking their own ubiquitylation. Here we examined how APC/C activity is suppressed by the small pseudosubstrate inhibitor Acm1 from budding yeast (Saccharomyces cerevisiae). Mutation of a conserved D-box converted Acm1 into an efficient ABBA (cyclin A, BubR1, Bub1, Acm1) motif-dependent APC/CCdh1 substrate in vivo, suggesting that this D-box somehow inhibits APC/C. We then identified a short conserved sequence at the C terminus of the Acm1 D-box that was necessary and sufficient for APC/C inhibition. In several APC/C substrates, the corresponding D-box region proved to be important for their degradation despite poor sequence conservation, redefining the D-box as a 12-amino acid motif. Biochemical analysis suggested that the Acm1 D-box extension inhibits reaction processivity by perturbing the normal interaction with Doc1/Apc10. Our results reveal a simple, elegant mode of pseudosubstrate inhibition that combines high-affinity activator binding with specific disruption of Doc1/Apc10 function in processive ubiquitylation.
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Affiliation(s)
- Liang Qin
- Department of Biochemistry and Center for Cancer Research, Purdue University, West Lafayette, Indiana 47907
| | - Arda Mizrak
- Department of Physiology, University of California, San Francisco, California 94143.,Department of Biochemistry and Biophysics, University of California, San Francisco, California 94143
| | | | - Hana M Tambrin
- Department of Biochemistry and Center for Cancer Research, Purdue University, West Lafayette, Indiana 47907
| | - David O Morgan
- Department of Physiology, University of California, San Francisco, California 94143.,Department of Biochemistry and Biophysics, University of California, San Francisco, California 94143
| | - Mark C Hall
- Department of Biochemistry and Center for Cancer Research, Purdue University, West Lafayette, Indiana 47907
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38
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Zhang S, Tischer T, Barford D. Cyclin A2 degradation during the spindle assembly checkpoint requires multiple binding modes to the APC/C. Nat Commun 2019; 10:3863. [PMID: 31455778 PMCID: PMC6712056 DOI: 10.1038/s41467-019-11833-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 07/29/2019] [Indexed: 12/19/2022] Open
Abstract
The anaphase-promoting complex/cyclosome (APC/C) orchestrates cell cycle progression by controlling the temporal degradation of specific cell cycle regulators. Although cyclin A2 and cyclin B1 are both targeted for degradation by the APC/C, during the spindle assembly checkpoint (SAC), the mitotic checkpoint complex (MCC) represses APC/C's activity towards cyclin B1, but not cyclin A2. Through structural, biochemical and in vivo analysis, we identify a non-canonical D box (D2) that is critical for cyclin A2 ubiquitination in vitro and degradation in vivo. During the SAC, cyclin A2 is ubiquitinated by the repressed APC/C-MCC, mediated by the cooperative engagement of its KEN and D2 boxes, ABBA motif, and the cofactor Cks. Once the SAC is satisfied, cyclin A2 binds APC/C-Cdc20 through two mutually exclusive binding modes, resulting in differential ubiquitination efficiency. Our findings reveal that a single substrate can engage an E3 ligase through multiple binding modes, affecting its degradation timing and efficiency.
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Affiliation(s)
- Suyang Zhang
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
- Max Planck Institute for Biophysical Chemistry, Göttingen, 37077, Germany
| | - Thomas Tischer
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - David Barford
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK.
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39
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Interplay between Phosphatases and the Anaphase-Promoting Complex/Cyclosome in Mitosis. Cells 2019; 8:cells8080814. [PMID: 31382469 PMCID: PMC6721574 DOI: 10.3390/cells8080814] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 07/25/2019] [Accepted: 08/01/2019] [Indexed: 12/14/2022] Open
Abstract
Accurate division of cells into two daughters is a process that is vital to propagation of life. Protein phosphorylation and selective degradation have emerged as two important mechanisms safeguarding the delicate choreography of mitosis. Protein phosphatases catalyze dephosphorylation of thousands of sites on proteins, steering the cells through establishment of the mitotic phase and exit from it. A large E3 ubiquitin ligase, the anaphase-promoting complex/cyclosome (APC/C) becomes active during latter stages of mitosis through G1 and marks hundreds of proteins for destruction. Recent studies have revealed the complex interregulation between these two classes of enzymes. In this review, we highlight the direct and indirect mechanisms by which phosphatases and the APC/C mutually influence each other to ensure accurate spatiotemporal and orderly progression through mitosis, with a particular focus on recent insights and conceptual advances.
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40
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Phospho-peptide binding domains in S. cerevisiae model organism. Biochimie 2019; 163:117-127. [PMID: 31194995 DOI: 10.1016/j.biochi.2019.06.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Accepted: 06/06/2019] [Indexed: 02/07/2023]
Abstract
Protein phosphorylation is one of the main mechanisms by which signals are transmitted in eukaryotic cells, and it plays a crucial regulatory role in almost all cellular processes. In yeast, more than half of the proteins are phosphorylated in at least one site, and over 20,000 phosphopeptides have been experimentally verified. However, the functional consequences of these phosphorylation events for most of the identified phosphosites are unknown. A family of protein interaction domains selectively recognises phosphorylated motifs to recruit regulatory proteins and activate signalling pathways. Nine classes of dedicated modules are coded by the yeast genome: 14-3-3, FHA, WD40, BRCT, WW, PBD, and SH2. The recognition specificity relies on a few residues on the target protein and has coevolved with kinase specificity. In the present study, we review the current knowledge concerning yeast phospho-binding domains and their networks. We emphasise the relevance of both positive and negative amino acid selection to orchestrate the highly regulated outcomes of inter- and intra-molecular interactions. Finally, we hypothesise that only a small fraction of yeast phosphorylation events leads to the creation of a docking site on the target molecule, while many have a direct effect on the protein or, as has been proposed, have no function at all.
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41
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Wood DJ, Endicott JA. Structural insights into the functional diversity of the CDK-cyclin family. Open Biol 2019; 8:rsob.180112. [PMID: 30185601 PMCID: PMC6170502 DOI: 10.1098/rsob.180112] [Citation(s) in RCA: 141] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 08/10/2018] [Indexed: 12/17/2022] Open
Abstract
Since their characterization as conserved modules that regulate progression through the eukaryotic cell cycle, cyclin-dependent protein kinases (CDKs) in higher eukaryotic cells are now also emerging as significant regulators of transcription, metabolism and cell differentiation. The cyclins, though originally characterized as CDK partners, also have CDK-independent roles that include the regulation of DNA damage repair and transcriptional programmes that direct cell differentiation, apoptosis and metabolic flux. This review compares the structures of the members of the CDK and cyclin families determined by X-ray crystallography, and considers what mechanistic insights they provide to guide functional studies and distinguish CDK- and cyclin-specific activities. Aberrant CDK activity is a hallmark of a number of diseases, and structural studies can provide important insights to identify novel routes to therapy.
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Affiliation(s)
- Daniel J Wood
- Newcastle Cancer Centre, Northern Institute for Cancer Research, Medical School, Newcastle University, Paul O'Gorman Building, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Jane A Endicott
- Newcastle Cancer Centre, Northern Institute for Cancer Research, Medical School, Newcastle University, Paul O'Gorman Building, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
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42
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Koch BA, Jin H, Tomko RJ, Yu HG. The anaphase-promoting complex regulates the degradation of the inner nuclear membrane protein Mps3. J Cell Biol 2019; 218:839-854. [PMID: 30737264 PMCID: PMC6400550 DOI: 10.1083/jcb.201808024] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 12/04/2018] [Accepted: 01/09/2019] [Indexed: 01/08/2023] Open
Abstract
How resident inner nuclear membrane (INM) proteins are turned over is unclear. Koch et al. identify an APC/C-dependent mechanism controlling the degradation of Mps3, a conserved integral protein of the INM. The nucleus is enclosed by the inner nuclear membrane (INM) and the outer nuclear membrane (ONM). While the ONM is continuous with the endoplasmic reticulum (ER), the INM is independent and separates the nucleoplasm from the ER lumen. Turnover of ER proteins has been well characterized by the ER-associated protein degradation (ERAD) pathway, but very little is known about turnover of resident INM proteins. Here we show that the anaphase-promoting complex/cyclosome (APC/C), an E3 ubiquitin ligase, regulates the degradation of Mps3, a conserved integral protein of the INM. Turnover of Mps3 requires the ubiquitin-conjugating enzyme Ubc7, but was independent of the known ERAD ubiquitin ligases Doa10 and Hrd1 as well as the recently discovered Asi1–Asi3 complex. Using a genetic approach, we have found that Cdh1, a coactivator of APC/C, modulates Mps3 stability. APC/C controls Mps3 degradation through Mps3’s N terminus, which resides in the nucleoplasm and possesses two putative APC/C-dependent destruction motifs. Accumulation of Mps3 at the INM impairs nuclear morphological changes and cell division. Our findings therefore reveal an unexpected mechanism of APC/C-mediated protein degradation at the INM that coordinates nuclear morphogenesis and cell cycle progression.
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Affiliation(s)
- Bailey A Koch
- Department of Biological Science, Florida State University, Tallahassee, FL
| | - Hui Jin
- Department of Biological Science, Florida State University, Tallahassee, FL
| | - Robert J Tomko
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL
| | - Hong-Guo Yu
- Department of Biological Science, Florida State University, Tallahassee, FL
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43
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Levasseur MD, Thomas C, Davies OR, Higgins JMG, Madgwick S. Aneuploidy in Oocytes Is Prevented by Sustained CDK1 Activity through Degron Masking in Cyclin B1. Dev Cell 2019; 48:672-684.e5. [PMID: 30745144 PMCID: PMC6416240 DOI: 10.1016/j.devcel.2019.01.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 10/22/2018] [Accepted: 12/29/2018] [Indexed: 01/10/2023]
Abstract
Successful mitosis requires that cyclin B1:CDK1 kinase activity remains high until chromosomes are correctly aligned on the mitotic spindle. It has therefore been unclear why, in mammalian oocyte meiosis, cyclin B1 destruction begins before chromosome alignment is complete. Here, we resolve this paradox and show that mouse oocytes exploit an imbalance in the ratio of cyclin B1 to CDK1 to control CDK1 activity; early cyclin B1 destruction reflects the loss of an excess of non-CDK1-bound cyclin B1 in late prometaphase, while CDK1-bound cyclin B1 is destroyed only during metaphase. The ordered destruction of the two forms of cyclin B1 is brought about by a previously unidentified motif that is accessible in free cyclin B1 but masked when cyclin B1 is in complex with CDK1. This protects the CDK1-bound fraction from destruction in prometaphase, ensuring a period of prolonged CDK1 activity sufficient to achieve optimal chromosome alignment and prevent aneuploidy. In mouse oocytes, an excess of cyclin B1 preserves CDK1 activity A motif in non-CDK1-bound cyclin B1 confers preferential APC/C targeting Non-CDK1-bound cyclin B1 is gradually destroyed before CDK1-bound cyclin B1 Prolonged CDK1 activity assists the spindle checkpoint and prevents aneuploidy
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Affiliation(s)
- Mark D Levasseur
- Cell Division Biology Group, Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Christopher Thomas
- Cell Division Biology Group, Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Owen R Davies
- Cell Division Biology Group, Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Jonathan M G Higgins
- Cell Division Biology Group, Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Suzanne Madgwick
- Cell Division Biology Group, Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.
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44
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Abstract
The separation of sister chromatids at anaphase, which is regulated by an E3 ubiquitin ligase called the anaphase-promoting complex/cyclosome (APC/C), is arguably the most important irrevocable event during the cell cycle. The APC/C and cyclin-dependent kinase 1 (Cdk1) are just two of the many significant cell cycle regulators and exert control through ubiquitylation and phosphorylation, respectively. The temporal and spatial regulation of the APC/C is achieved by multiple mechanisms, including phosphorylation, interaction with the structurally related co-activators Cdc20 and Cdh1, loading of distinct E2 ubiquitin-conjugating enzymes, binding with inhibitors and differential affinities for various substrates. Since the discovery of APC/C 25 years ago, intensive studies have uncovered many aspects of APC/C regulation, but we are still far from a full understanding of this important cellular machinery. Recent high-resolution cryogenic electron microscopy analysis and reconstitution of the APC/C have greatly advanced our understanding of molecular mechanisms underpinning the enzymatic properties of APC/C. In this review, we will examine the historical background and current understanding of APC/C regulation.
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Affiliation(s)
- Hiroyuki Yamano
- Cell Cycle Control Group, UCL Cancer Institute, University College London, Paul O’Gorman Building, 72 Huntley Street, London, WC1E 6DD, UK
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45
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Curtis NL, Bolanos-Garcia VM. The Anaphase Promoting Complex/Cyclosome (APC/C): A Versatile E3 Ubiquitin Ligase. Subcell Biochem 2019; 93:539-623. [PMID: 31939164 DOI: 10.1007/978-3-030-28151-9_18] [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] [Indexed: 03/25/2023]
Abstract
In the present chapter we discuss the essential roles of the human E3 ubiquitin ligase Anaphase Promoting Complex/Cyclosome (APC/C) in mitosis as well as the emerging evidence of important APC/C roles in cellular processes beyond cell division control such as regulation of genomic integrity and cell differentiation of the nervous system. We consider the potential incipient role of APC/C dysregulation in the pathophysiology of the neurological disorder Alzheimer's disease (AD). We also discuss how certain Deoxyribonucleic Acid (DNA) and Ribonucleic Acid (RNA) viruses take control of the host's cell division regulatory system through harnessing APC/C ubiquitin ligase activity and hypothesise the plausible molecular mechanisms underpinning virus manipulation of the APC/C. We also examine how defects in the function of this multisubunit protein assembly drive abnormal cell proliferation and lastly argue the potential of APC/C as a promising therapeutic target for the development of innovative therapies for the treatment of chronic malignancies such as cancer.
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Affiliation(s)
- Natalie L Curtis
- Faculty of Health and Life Sciences, Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, OX3 0BP, England, UK
| | - Victor M Bolanos-Garcia
- Faculty of Health and Life Sciences, Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, OX3 0BP, England, UK.
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46
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Bonacci T, Suzuki A, Grant GD, Stanley N, Cook JG, Brown NG, Emanuele MJ. Cezanne/OTUD7B is a cell cycle-regulated deubiquitinase that antagonizes the degradation of APC/C substrates. EMBO J 2018; 37:embj.201798701. [PMID: 29973362 DOI: 10.15252/embj.201798701] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 06/14/2018] [Accepted: 06/15/2018] [Indexed: 11/09/2022] Open
Abstract
The anaphase-promoting complex/cyclosome (APC/C) is an E3 ubiquitin ligase and key regulator of cell cycle progression. Since APC/C promotes the degradation of mitotic cyclins, it controls cell cycle-dependent oscillations in cyclin-dependent kinase (CDK) activity. Both CDKs and APC/C control a large number of substrates and are regulated by analogous mechanisms, including cofactor-dependent activation. However, whereas substrate dephosphorylation is known to counteract CDK, it remains largely unknown whether deubiquitinating enzymes (DUBs) antagonize APC/C substrate ubiquitination during mitosis. Here, we demonstrate that Cezanne/OTUD7B is a cell cycle-regulated DUB that opposes the ubiquitination of APC/C targets. Cezanne is remarkably specific for K11-linked ubiquitin chains, which are formed by APC/C in mitosis. Accordingly, Cezanne binds established APC/C substrates and reverses their APC/C-mediated ubiquitination. Cezanne depletion accelerates APC/C substrate degradation and causes errors in mitotic progression and formation of micronuclei. These data highlight the importance of tempered APC/C substrate destruction in maintaining chromosome stability. Furthermore, Cezanne is recurrently amplified and overexpressed in numerous malignancies, suggesting a potential role in genome maintenance and cancer cell proliferation.
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Affiliation(s)
- Thomas Bonacci
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Aussie Suzuki
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Gavin D Grant
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,Department of Biochemistry and Biophysics, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Natalie Stanley
- Curriculum in Bioinformatics and Computational Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Jeanette G Cook
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,Department of Biochemistry and Biophysics, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Nicholas G Brown
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Michael J Emanuele
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA .,Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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47
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Atkins KC, Cross FR. Interregulation of CDKA/CDK1 and the Plant-Specific Cyclin-Dependent Kinase CDKB in Control of the Chlamydomonas Cell Cycle. THE PLANT CELL 2018; 30:429-446. [PMID: 29367304 PMCID: PMC5868683 DOI: 10.1105/tpc.17.00759] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Revised: 11/17/2017] [Accepted: 01/24/2018] [Indexed: 05/09/2023]
Abstract
The cyclin-dependent kinase CDK1 is essential for mitosis in fungi and animals. Plant genomes contain the CDK1 ortholog CDKA and a plant kingdom-specific relative, CDKB. The green alga Chlamydomonas reinhardtii has a long G1 growth period followed by rapid cycles of DNA replication and cell division. We show that null alleles of CDKA extend the growth period prior to the first division cycle and modestly extend the subsequent division cycles, but do not prevent cell division, indicating at most a minor role for the CDK1 ortholog in mitosis in Chlamydomonas. A null allele of cyclin A has a similar though less extreme phenotype. In contrast, both CDKB and cyclin B are essential for mitosis. CDK kinase activity measurements imply that the predominant in vivo complexes are probably cyclin A-CDKA and cyclin B-CDKB. We propose a negative feedback loop: CDKA activates cyclin B-CDKB. Cyclin B-CDKB in turn promotes mitotic entry and inactivates cyclin A-CDKA. Cyclin A-CDKA and cyclin B-CDKB may redundantly promote DNA replication. We show that the anaphase-promoting complex is required for inactivation of both CDKA and CDKB and is essential for anaphase. These results are consistent with findings in Arabidopsis thaliana and may delineate the core of plant kingdom cell cycle control that, compared with the well-studied yeast and animal systems, exhibits deep conservation in some respects and striking divergence in others.
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Degradation of FBXO31 by APC/C is regulated by AKT- and ATM-mediated phosphorylation. Proc Natl Acad Sci U S A 2018; 115:998-1003. [PMID: 29343641 DOI: 10.1073/pnas.1705954115] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The F-box protein FBXO31 is a tumor suppressor that is encoded in 16q24.3, for which there is loss of heterozygosity in various solid tumors. FBXO31 serves as the substrate-recognition component of the SKP/Cullin/F-box protein class of E3 ubiquitin ligases and has been shown to direct degradation of pivotal cell-cycle regulatory proteins including cyclin D1 and the p53 antagonist MDM2. FBXO31 levels are normally low but increase substantially following genotoxic stress through a mechanism that remains to be determined. Here we show that the low levels of FBXO31 are maintained through proteasomal degradation by anaphase-promoting complex/cyclosome (APC/C). We find that the APC/C coactivators CDH1 and CDC20 bind to a destruction-box (D-box) motif present in FBXO31 to promote its polyubiquitination and degradation in a cell-cycle-regulated manner, which requires phosphorylation of FBXO31 on serine-33 by the prosurvival kinase AKT. Following genotoxic stress, phosphorylation of FBXO31 on serine-278 by another kinase, the DNA damage kinase ATM, results in disruption of its interaction with CDH1 and CDC20, thereby preventing FBXO31 degradation. Collectively, our results reveal how alterations in FBXO31 phosphorylation, mediated by AKT and ATM, underlie physiological regulation of FBXO31 levels in unstressed and genotoxically stressed cells.
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49
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APC/C FZR-1 Controls SAS-5 Levels To Regulate Centrosome Duplication in Caenorhabditis elegans. G3-GENES GENOMES GENETICS 2017; 7:3937-3946. [PMID: 29030390 PMCID: PMC5714490 DOI: 10.1534/g3.117.300260] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
As the primary microtubule-organizing center, centrosomes play a key role in establishing mitotic bipolar spindles that secure correct transmission of genomic content. For the fidelity of cell division, centrosome number must be strictly controlled by duplicating only once per cell cycle. Proper levels of centrosome proteins are shown to be critical for normal centrosome number and function. Overexpressing core centrosome factors leads to extra centrosomes, while depleting these factors results in centrosome duplication failure. In this regard, protein turnover by the ubiquitin-proteasome system provides a vital mechanism for the regulation of centrosome protein levels. Here, we report that FZR-1, the Caenorhabditis elegans homolog of Cdh1/Hct1/Fzr, a coactivator of the anaphase promoting complex/cyclosome (APC/C), an E3 ubiquitin ligase, functions as a negative regulator of centrosome duplication in the C. elegans embryo. During mitotic cell division in the early embryo, FZR-1 is associated with centrosomes and enriched at nuclei. Loss of fzr-1 function restores centrosome duplication and embryonic viability to the hypomorphic zyg-1(it25) mutant, in part, through elevated levels of SAS-5 at centrosomes. Our data suggest that the APC/CFZR-1 regulates SAS-5 levels by directly recognizing the conserved KEN-box motif, contributing to proper centrosome duplication. Together, our work shows that FZR-1 plays a conserved role in regulating centrosome duplication in C. elegans.
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50
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Taming the Beast: Control of APC/C Cdc20-Dependent Destruction. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2017; 82:111-121. [PMID: 29133301 DOI: 10.1101/sqb.2017.82.033712] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The anaphase-promoting complex/cyclosome (APC/C) is a large multisubunit ubiquitin ligase that triggers the metaphase-to-anaphase transition in the cell cycle by targeting the substrates cyclin B and securin for destruction. APC/C activity toward these two key substrates requires the coactivator Cdc20. To ensure that cells enter mitosis and partition their duplicated genome with high accuracy, APC/CCdc20 activity must be tightly controlled. Here, we discuss the mechanisms that regulate APC/CCdc20 activity both before and during mitosis. We focus our discussion primarily on the chromosomal pathways that both accelerate and delay APC/C activation by targeting Cdc20 to opposing fates. The findings discussed provide an overview of how cells control the activation of this major cell cycle regulator to ensure both accurate and timely cell division.
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