1
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Bai S, Sun L, Wang X, Wang SM, Luo ZQ, Wang Y, Jin QW. Recovery from spindle checkpoint-mediated arrest requires a novel Dnt1-dependent APC/C activation mechanism. PLoS Genet 2022; 18:e1010397. [PMID: 36108046 PMCID: PMC9514617 DOI: 10.1371/journal.pgen.1010397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 09/27/2022] [Accepted: 08/24/2022] [Indexed: 11/19/2022] Open
Abstract
The activated spindle assembly checkpoint (SAC) potently inhibits the anaphase-promoting complex/cyclosome (APC/C) to ensure accurate chromosome segregation at anaphase. Early studies have recognized that the SAC should be silenced within minutes to enable rapid APC/C activation and synchronous segregation of chromosomes once all kinetochores are properly attached, but the underlying silencers are still being elucidated. Here, we report that the timely silencing of SAC in fission yeast requires dnt1+, which causes severe thiabendazole (TBZ) sensitivity and increased rate of lagging chromosomes when deleted. The absence of Dnt1 results in prolonged inhibitory binding of mitotic checkpoint complex (MCC) to APC/C and attenuated protein levels of Slp1Cdc20, consequently slows the degradation of cyclin B and securin, and eventually delays anaphase entry in cells released from SAC activation. Interestingly, Dnt1 physically associates with APC/C upon SAC activation. We propose that this association may fend off excessive and prolonged MCC binding to APC/C and help to maintain Slp1Cdc20 stability. This may allow a subset of APC/C to retain activity, which ensures rapid anaphase onset and mitotic exit once SAC is inactivated. Therefore, our study uncovered a new player in dictating the timing and efficacy of APC/C activation, which is actively required for maintaining cell viability upon recovery from the inhibition of APC/C by spindle checkpoint.
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Affiliation(s)
- Shuang Bai
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Li Sun
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Xi Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Shuang-min Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Zhou-qing Luo
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian, China
- * E-mail: (ZL); (YW); (QJ)
| | - Yamei Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian, China
- * E-mail: (ZL); (YW); (QJ)
| | - Quan-wen Jin
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian, China
- * E-mail: (ZL); (YW); (QJ)
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2
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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: 56] [Impact Index Per Article: 14.0] [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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3
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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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4
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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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5
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Watson ER, Brown NG, Peters JM, Stark H, Schulman BA. Posing the APC/C E3 Ubiquitin Ligase to Orchestrate Cell Division. Trends Cell Biol 2018; 29:117-134. [PMID: 30482618 DOI: 10.1016/j.tcb.2018.09.007] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 09/23/2018] [Accepted: 09/25/2018] [Indexed: 01/01/2023]
Abstract
The anaphase promoting complex/cyclosome (APC/C) E3 ligase controls mitosis and nonmitotic pathways through interactions with proteins that coordinate ubiquitylation. Since the discovery that the catalytic subunits of APC/C are conformationally dynamic cullin and RING proteins, many unexpected and intricate regulatory mechanisms have emerged. Here, we review structural knowledge of this regulation, focusing on: (i) coactivators, E2 ubiquitin (Ub)-conjugating enzymes, and inhibitors engage or influence multiple sites on APC/C including the cullin-RING catalytic core; and (ii) the outcomes of these interactions rely on mobility of coactivators and cullin-RING domains, which permits distinct conformations specifying different functions. Thus, APC/C is not simply an interaction hub, but is instead a dynamic, multifunctional molecular machine whose structure is remodeled by binding partners to achieve temporal ubiquitylation regulating cell division.
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Affiliation(s)
- Edmond R Watson
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, 82152, Germany
| | - Nicholas G Brown
- Department of Pharmacology and Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Jan-Michael Peters
- Research Institute of Molecular Pathology (IMP), Campus Vienna Biocenter (VBC) 1, 1030 Vienna, Austria
| | - Holger Stark
- Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Brenda A Schulman
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, 82152, Germany; Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
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6
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Alfieri C, Zhang S, Barford D. Visualizing the complex functions and mechanisms of the anaphase promoting complex/cyclosome (APC/C). Open Biol 2017; 7:170204. [PMID: 29167309 PMCID: PMC5717348 DOI: 10.1098/rsob.170204] [Citation(s) in RCA: 104] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 10/10/2017] [Indexed: 12/17/2022] Open
Abstract
The anaphase promoting complex or cyclosome (APC/C) is a large multi-subunit E3 ubiquitin ligase that orchestrates cell cycle progression by mediating the degradation of important cell cycle regulators. During the two decades since its discovery, much has been learnt concerning its role in recognizing and ubiquitinating specific proteins in a cell-cycle-dependent manner, the mechanisms governing substrate specificity, the catalytic process of assembling polyubiquitin chains on its target proteins, and its regulation by phosphorylation and the spindle assembly checkpoint. The past few years have witnessed significant progress in understanding the quantitative mechanisms underlying these varied APC/C functions. This review integrates the overall functions and properties of the APC/C with mechanistic insights gained from recent cryo-electron microscopy (cryo-EM) studies of reconstituted human APC/C complexes.
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Affiliation(s)
- Claudio Alfieri
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Suyang Zhang
- 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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7
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Takizawa Y, Binshtein E, Erwin AL, Pyburn TM, Mittendorf KF, Ohi MD. While the revolution will not be crystallized, biochemistry reigns supreme. Protein Sci 2016; 26:69-81. [PMID: 27673321 DOI: 10.1002/pro.3054] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 09/22/2016] [Indexed: 12/14/2022]
Abstract
Single-particle cryo-electron microscopy (EM) is currently gaining attention for the ability to calculate structures that reach sub-5 Å resolutions; however, the technique is more than just an alternative approach to X-ray crystallography. Molecular machines work via dynamic conformational changes, making structural flexibility the hallmark of function. While the dynamic regions in molecules are essential, they are also the most challenging to structurally characterize. Single-particle EM has the distinct advantage of being able to directly visualize purified molecules without the formation of ordered arrays of molecules locked into identical conformations. Additionally, structures determined using single-particle EM can span resolution ranges from very low- to atomic-levels (>30-1.8 Å), sometimes even in the same structure. The ability to accommodate various resolutions gives single-particle EM the unique capacity to structurally characterize dynamic regions of biological molecules, thereby contributing essential structural information needed for the development of molecular models that explain function. Further, many important molecular machines are intrinsically dynamic and compositionally heterogeneous. Structures of these complexes may never reach sub-5 Å resolutions due to this flexibility required for function. Thus, the biochemical quality of the sample, as well as, the calculation and interpretation of low- to mid-resolution cryo-EM structures (30-8 Å) remains critical for generating insights into the architecture of many challenging biological samples that cannot be visualized using alternative techniques.
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Affiliation(s)
- Yoshimasa Takizawa
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, 37232.,Center for Structural Biology Vanderbilt University, Nashville, Tennessee, 37232
| | - Elad Binshtein
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, 37232.,Center for Structural Biology Vanderbilt University, Nashville, Tennessee, 37232
| | - Amanda L Erwin
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, 37232.,Center for Structural Biology Vanderbilt University, Nashville, Tennessee, 37232
| | - Tasia M Pyburn
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, 37232.,Center for Structural Biology Vanderbilt University, Nashville, Tennessee, 37232
| | - Kathleen F Mittendorf
- Vanderbilt-Ingram Cancer Center Vanderbilt University Medical Center, Nashville, Tennessee, 37232
| | - Melanie D Ohi
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, 37232.,Center for Structural Biology Vanderbilt University, Nashville, Tennessee, 37232
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8
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Abstract
In this review, Huang and Bonni discuss the functions and mechanisms of the anaphase-promoting complex in neurogenesis; glial differentiation and migration; neuronal survival, metabolism, and morphogenesis; synapse formation and plasticity; and learning and memory. Control of protein abundance by the ubiquitin–proteasome system is essential for normal brain development and function. Just over a decade ago, the first post-mitotic function of the anaphase-promoting complex, a major cell cycle-regulated E3 ubiquitin ligase, was discovered in the control of axon growth and patterning in the mammalian brain. Since then, a large number of studies have identified additional novel roles for the anaphase-promoting complex in diverse aspects of neuronal connectivity and plasticity in the developing and mature nervous system. In this review, we discuss the functions and mechanisms of the anaphase-promoting complex in neurogenesis, glial differentiation and migration, neuronal survival and metabolism, neuronal morphogenesis, synapse formation and plasticity, and learning and memory. We also provide a perspective on future investigations of the anaphase-promoting complex in neurobiology.
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Affiliation(s)
- Ju Huang
- Department of Neuroscience, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Azad Bonni
- Department of Neuroscience, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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9
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Sivakumar S, Gorbsky GJ. Spatiotemporal regulation of the anaphase-promoting complex in mitosis. Nat Rev Mol Cell Biol 2015; 16:82-94. [PMID: 25604195 DOI: 10.1038/nrm3934] [Citation(s) in RCA: 198] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The appropriate timing of events that lead to chromosome segregation during mitosis and cytokinesis is essential to prevent aneuploidy, and defects in these processes can contribute to tumorigenesis. Key mitotic regulators are controlled through ubiquitylation and proteasome-mediated degradation. The APC/C (anaphase-promoting complex; also known as the cyclosome) is an E3 ubiquitin ligase that has a crucial function in the regulation of the mitotic cell cycle, particularly at the onset of anaphase and during mitotic exit. Co-activator proteins, inhibitor proteins, protein kinases and phosphatases interact with the APC/C to temporally and spatially control its activity and thus ensure accurate timing of mitotic events.
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Affiliation(s)
- Sushama Sivakumar
- Cell Cycle and Cancer Biology, Oklahoma Medical Research Foundation, 825 NE 13th Street, Oklahoma City, Oklahoma 73104, USA
| | - Gary J Gorbsky
- Cell Cycle and Cancer Biology, Oklahoma Medical Research Foundation, 825 NE 13th Street, Oklahoma City, Oklahoma 73104, USA
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10
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Masuda K, Chiyoda T, Sugiyama N, Segura-Cabrera A, Kabe Y, Ueki A, Banno K, Suematsu M, Aoki D, Ishihama Y, Saya H, Kuninaka S. LATS1 and LATS2 phosphorylate CDC26 to modulate assembly of the tetratricopeptide repeat subcomplex of APC/C. PLoS One 2015; 10:e0118662. [PMID: 25723520 PMCID: PMC4344199 DOI: 10.1371/journal.pone.0118662] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Accepted: 01/09/2015] [Indexed: 12/15/2022] Open
Abstract
In budding yeast, the Mitotic Exit Network (MEN) regulates anaphase promoting complex/cyclosome (APC/C) via the Dbf2-Cdc14 signaling cascade. Dbf2 kinase phosphorylates and activates Cdc14 phosphatase, which removes the inhibitory phosphorylation of the APC/C cofactor Cdh1. Although each component of the MEN was highly conserved during evolution, there is presently no evidence supporting direct phosphorylation of CDC14 by large tumor suppressor kinase 1 (LATS1), the human counterpart of Dbf2; hence, it is unclear how LATS1 regulates APC/C. Here, we demonstrate that LATS1 phosphorylates the Thr7 (T7) residue of the APC/C component CDC26 directly. Nocodazole-induced phosphorylation of T7 was reduced by knockdown of LATS1 and LATS2 in HeLa cells, indicating that both of these kinases contribute to the phosphorylation of CDC26 in vivo. The T7 residue of CDC26 is critical for its interaction with APC6, a tetratricopeptide repeat-containing subunit of APC/C, and mutation of this residue to Asp (T7D) reduced the interaction of CDC26 with APC6. Replacement of endogenous CDC26 in HeLa cells with exogenous phosphor-mimic T7D-mutated CDC26 increased the elution size of APC/C subunits in a gel filtration assay, implying a change in the APC/C assembly upon phosphorylation of CDC26. Furthermore, T7D-mutated CDC26 promoted the ubiquitination of polo-like kinase 1, a well-known substrate of APC/C. Overall, these results suggest that LATS1/2 are novel kinases involved in APC/C phosphorylation and indicate a direct regulatory link between LATS1/2 and APC/C.
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Affiliation(s)
- Kenta Masuda
- Division of Gene Regulation, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan
- Department of Obstetrics and Gynecology, Keio University School of Medicine, Tokyo, Japan
| | - Tatsuyuki Chiyoda
- Division of Gene Regulation, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan
- Department of Obstetrics and Gynecology, Keio University School of Medicine, Tokyo, Japan
| | - Naoyuki Sugiyama
- Department of Molecular & Cellular BioAnalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
| | - Aldo Segura-Cabrera
- Division of Experimental Hematology & Cancer Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Yasuaki Kabe
- Department of Biochemistry, Keio University School of Medicine, Tokyo, Japan
| | - Arisa Ueki
- Division of Gene Regulation, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan
- Department of Obstetrics and Gynecology, Keio University School of Medicine, Tokyo, Japan
| | - Koji Banno
- Department of Obstetrics and Gynecology, Keio University School of Medicine, Tokyo, Japan
| | - Makoto Suematsu
- Department of Biochemistry, Keio University School of Medicine, Tokyo, Japan
- CREST, Japan Science and Technology Agency, Tokyo, Japan
| | - Daisuke Aoki
- Department of Obstetrics and Gynecology, Keio University School of Medicine, Tokyo, Japan
| | - Yasushi Ishihama
- Department of Molecular & Cellular BioAnalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
| | - Hideyuki Saya
- Division of Gene Regulation, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan
- * E-mail: (SK); (HS)
| | - Shinji Kuninaka
- Division of Gene Regulation, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan
- * E-mail: (SK); (HS)
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11
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Yamaguchi M, Yu S, Qiao R, Weissmann F, Miller DJ, VanderLinden R, Brown NG, Frye JJ, Peters JM, Schulman BA. Structure of an APC3-APC16 complex: insights into assembly of the anaphase-promoting complex/cyclosome. J Mol Biol 2014; 427:1748-64. [PMID: 25490258 DOI: 10.1016/j.jmb.2014.11.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Revised: 11/14/2014] [Accepted: 11/15/2014] [Indexed: 01/05/2023]
Abstract
The anaphase-promoting complex/cyclosome (APC/C) is a massive E3 ligase that controls mitosis by catalyzing ubiquitination of key cell cycle regulatory proteins. The APC/C assembly contains two subcomplexes: the "Platform" centers around a cullin-RING-like E3 ligase catalytic core; the "Arc Lamp" is a hub that mediates transient association with regulators and ubiquitination substrates. The Arc Lamp contains the small subunits APC16, CDC26, and APC13, and tetratricopeptide repeat (TPR) proteins (APC7, APC3, APC6, and APC8) that homodimerize and stack with quasi-2-fold symmetry. Within the APC/C complex, APC3 serves as center for regulation. APC3's TPR motifs recruit substrate-binding coactivators, CDC20 and CDH1, via their C-terminal conserved Ile-Arg (IR) tail sequences. Human APC3 also binds APC16 and APC7 and contains a >200-residue loop that is heavily phosphorylated during mitosis, although the basis for APC3 interactions and whether loop phosphorylation is required for ubiquitination are unclear. Here, we map the basis for human APC3 assembly with APC16 and APC7, report crystal structures of APC3Δloop alone and in complex with the C-terminal domain of APC16, and test roles of APC3's loop and IR tail binding surfaces in APC/C-catalyzed ubiquitination. The structures show how one APC16 binds asymmetrically to the symmetric APC3 dimer and, together with biochemistry and prior data, explain how APC16 recruits APC7 to APC3, show how APC3's C-terminal domain is rearranged in the full APC/C assembly, and visualize residues in the IR tail binding cleft important for coactivator-dependent ubiquitination. Overall, the results provide insights into assembly, regulation, and interactions of TPR proteins and the APC/C.
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Affiliation(s)
- Masaya Yamaguchi
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Shanshan Yu
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Renping Qiao
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), 1030 Vienna, Austria
| | - Florian Weissmann
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), 1030 Vienna, Austria
| | - Darcie J Miller
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Ryan VanderLinden
- Howard Hughes Medical Institute, St. Jude Children's Research Hospital, Memphis, TN 38105 USA
| | - Nicholas G Brown
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Jeremiah J Frye
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Jan-Michael Peters
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), 1030 Vienna, Austria
| | - Brenda A Schulman
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA; Howard Hughes Medical Institute, St. Jude Children's Research Hospital, Memphis, TN 38105 USA.
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12
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Chang L, Barford D. Insights into the anaphase-promoting complex: a molecular machine that regulates mitosis. Curr Opin Struct Biol 2014; 29:1-9. [PMID: 25174288 DOI: 10.1016/j.sbi.2014.08.003] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 08/01/2014] [Accepted: 08/05/2014] [Indexed: 12/13/2022]
Abstract
The anaphase-promoting complex/cyclosome (APC/C) is a large multimeric complex that functions as a RING domain E3 ubiquitin ligase to regulate ordered transitions through the cell cycle. It does so by controlling the ubiquitin-mediated proteolysis of cell cycle proteins, notably cyclins and securins, whose degradation triggers sister chromatid disjunction and mitotic exit. Regulation of APC/C activity and modulation of its substrate specificity are subject to intricate cell cycle checkpoints and control mechanisms involving the switching of substrate-specifying cofactors, association of regulatory protein complexes and post-translational modifications. This review discusses the recent progress towards understanding the overall architecture of the APC/C, the molecular basis for degron recognition and ubiquitin chain synthesis, and how these activities are regulated.
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Affiliation(s)
- Leifu Chang
- 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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13
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Chang LF, Zhang Z, Yang J, McLaughlin SH, Barford D. Molecular architecture and mechanism of the anaphase-promoting complex. Nature 2014; 513:388-393. [PMID: 25043029 PMCID: PMC4456660 DOI: 10.1038/nature13543] [Citation(s) in RCA: 157] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 05/28/2014] [Indexed: 12/12/2022]
Abstract
The ubiquitination of cell cycle regulatory proteins by the anaphase-promoting complex/cyclosome (APC/C) controls sister chromatid segregation, cytokinesis and the establishment of the G1 phase of the cell cycle. The APC/C is an unusually large multimeric cullin-RING ligase. Its activity is strictly dependent on regulatory coactivator subunits that promote APC/C-substrate interactions and stimulate its catalytic reaction. Because the structures of many APC/C subunits and their organization within the assembly are unknown, the molecular basis for these processes is poorly understood. Here, from a cryo-electron microscopy reconstruction of a human APC/C-coactivator-substrate complex at 7.4 Å resolution, we have determined the complete secondary structural architecture of the complex. With this information we identified protein folds for structurally uncharacterized subunits, and the definitive location of all 20 APC/C subunits within the 1.2 MDa assembly. Comparison with apo APC/C shows that the coactivator promotes a profound allosteric transition involving displacement of the cullin-RING catalytic subunits relative to the degron-recognition module of coactivator and APC10. This transition is accompanied by increased flexibility of the cullin-RING subunits and enhanced affinity for UBCH10-ubiquitin, changes which may contribute to coactivator-mediated stimulation of APC/C E3 ligase activity.
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Affiliation(s)
- Lei-Fu Chang
- Division of Structural Biology, Institute of Cancer Research, 237 Fulham Road, London, SW3 6JB, UK
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Ziguo Zhang
- Division of Structural Biology, Institute of Cancer Research, 237 Fulham Road, London, SW3 6JB, UK
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Jing Yang
- Division of Structural Biology, Institute of Cancer Research, 237 Fulham Road, London, SW3 6JB, UK
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | | | - David Barford
- Division of Structural Biology, Institute of Cancer Research, 237 Fulham Road, London, SW3 6JB, UK
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
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14
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Silva PMA, Reis RM, Bolanos-Garcia VM, Florindo C, Tavares ÁA, Bousbaa H. Dynein-dependent transport of spindle assembly checkpoint proteins off kinetochores toward spindle poles. FEBS Lett 2014; 588:3265-73. [PMID: 25064841 DOI: 10.1016/j.febslet.2014.07.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 06/24/2014] [Accepted: 07/15/2014] [Indexed: 12/31/2022]
Abstract
A predominant mechanism of spindle assembly checkpoint (SAC) silencing is dynein-mediated transport of certain kinetochore proteins along microtubules. There are still conflicting data as to which SAC proteins are dynein cargoes. Using two ATP reduction assays, we found that the core SAC proteins Mad1, Mad2, Bub1, BubR1, and Bub3 redistributed from attached kinetochores to spindle poles, in a dynein-dependent manner. This redistribution still occurred in metaphase-arrested cells, at a time when the SAC should be satisfied and silenced. Unexpectedly, we found that a pool of Hec1 and Mis12 also relocalizes to spindle poles, suggesting KMN components as additional dynein cargoes. The potential significance of these results for SAC silencing is discussed.
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Affiliation(s)
- Patrícia M A Silva
- CESPU, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde, Rua Central de Gandra, 1317, 4585-116 Gandra PRD, Portugal; Centre for Molecular and Structural Biomedicine,CBME/IBB, University of Algarve, Faro 8005-139, Portugal
| | - Rita M Reis
- CESPU, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde, Rua Central de Gandra, 1317, 4585-116 Gandra PRD, Portugal
| | - Victor M Bolanos-Garcia
- Faculty of Health and Life Sciences, Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Claudia Florindo
- Centre for Molecular and Structural Biomedicine,CBME/IBB, University of Algarve, Faro 8005-139, Portugal; Departamento Ciências Biomédicas e Medicina, University of Algarve, Faro 8005-139, Portugal
| | - Álvaro A Tavares
- Centre for Molecular and Structural Biomedicine,CBME/IBB, University of Algarve, Faro 8005-139, Portugal; Departamento Ciências Biomédicas e Medicina, University of Algarve, Faro 8005-139, Portugal
| | - Hassan Bousbaa
- CESPU, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde, Rua Central de Gandra, 1317, 4585-116 Gandra PRD, Portugal; Centro de Química Medicinal da Universidade do Porto (CEQUIMED-UP), Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal; Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR), Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal.
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15
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Zhang J, Wan L, Dai X, Sun Y, Wei W. Functional characterization of Anaphase Promoting Complex/Cyclosome (APC/C) E3 ubiquitin ligases in tumorigenesis. Biochim Biophys Acta Rev Cancer 2014; 1845:277-93. [PMID: 24569229 DOI: 10.1016/j.bbcan.2014.02.001] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Revised: 02/09/2014] [Accepted: 02/12/2014] [Indexed: 12/25/2022]
Abstract
The Anaphase Promoting Complex/Cyclosome (APC/C) is a multi-subunit E3 ubiquitin ligase that primarily governs cell cycle progression. APC/C is composed of at least 14 core subunits and recruits its substrates for ubiquitination via one of the two adaptor proteins, Cdc20 or Cdh1, in M or M/early G1 phase, respectively. Furthermore, recent studies have shed light on crucial functions for APC/C in maintaining genomic integrity, neuronal differentiation, cellular metabolism and tumorigenesis. To gain better insight into the in vivo physiological functions of APC/C in regulating various cellular processes, particularly development and tumorigenesis, a number of mouse models of APC/C core subunits, coactivators or inhibitors have been established and characterized. However, due to their essential role in cell cycle regulation, most of the germline knockout mice targeting the APC/C pathway are embryonic lethal, indicating the need for generating conditional knockout mouse models to assess the role in tumorigenesis for each APC/C signaling component in specific tissues. In this review, we will first provide a brief introduction of the ubiquitin-proteasome system (UPS) and the biochemical activities and cellular functions of the APC/C E3 ligase. We will then focus primarily on characterizing genetic mouse models used to understand the physiological roles of each APC/C signaling component in embryogenesis, cell proliferation, development and carcinogenesis. Finally, we discuss future research directions to further elucidate the physiological contributions of APC/C components during tumorigenesis and validate their potentials as a novel class of anti-cancer targets.
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Affiliation(s)
- Jinfang Zhang
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Lixin Wan
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Xiangpeng Dai
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Yi Sun
- Division of Radiation and Cancer Biology, Department of Radiation Oncology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Wenyi Wei
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
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16
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Zhang Z, Chang L, Yang J, Conin N, Kulkarni K, Barford D. The four canonical tpr subunits of human APC/C form related homo-dimeric structures and stack in parallel to form a TPR suprahelix. J Mol Biol 2013; 425:4236-48. [PMID: 23583778 PMCID: PMC3898896 DOI: 10.1016/j.jmb.2013.04.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Revised: 03/28/2013] [Accepted: 04/05/2013] [Indexed: 12/18/2022]
Abstract
The anaphase-promoting complex or cyclosome (APC/C) is a large E3 RING-cullin ubiquitin ligase composed of between 14 and 15 individual proteins. A striking feature of the APC/C is that only four proteins are involved in directly recognizing target proteins and catalyzing the assembly of a polyubiquitin chain. All other subunits, which account for >80% of the mass of the APC/C, provide scaffolding functions. A major proportion of these scaffolding subunits are structurally related. In metazoans, there are four canonical tetratricopeptide repeat (TPR) proteins that form homo-dimers (Apc3/Cdc27, Apc6/Cdc16, Apc7 and Apc8/Cdc23). Here, we describe the crystal structure of the N-terminal homo-dimerization domain of Schizosaccharomyces pombe Cdc23 (Cdc23(Nterm)). Cdc23(Nterm) is composed of seven contiguous TPR motifs that self-associate through a related mechanism to those of Cdc16 and Cdc27. Using the Cdc23(Nterm) structure, we generated a model of full-length Cdc23. The resultant "V"-shaped molecule docks into the Cdc23-assigned density of the human APC/C structure determined using negative stain electron microscopy (EM). Based on sequence conservation, we propose that Apc7 forms a homo-dimeric structure equivalent to those of Cdc16, Cdc23 and Cdc27. The model is consistent with the Apc7-assigned density of the human APC/C EM structure. The four canonical homo-dimeric TPR proteins of human APC/C stack in parallel on one side of the complex. Remarkably, the uniform relative packing of neighboring TPR proteins generates a novel left-handed suprahelical TPR assembly. This finding has implications for understanding the assembly of other TPR-containing multimeric complexes.
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Affiliation(s)
| | | | | | | | - Kiran Kulkarni
- Division of Structural Biology, Institute of Cancer Research, Chester Beatty Laboratories, 237 Fulham Road, London SW3 6JB, UK
| | - David Barford
- Division of Structural Biology, Institute of Cancer Research, Chester Beatty Laboratories, 237 Fulham Road, London SW3 6JB, UK
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17
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Heinrich S, Geissen EM, Kamenz J, Trautmann S, Widmer C, Drewe P, Knop M, Radde N, Hasenauer J, Hauf S. Determinants of robustness in spindle assembly checkpoint signalling. Nat Cell Biol 2013; 15:1328-39. [DOI: 10.1038/ncb2864] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 09/20/2013] [Indexed: 02/08/2023]
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18
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Abstract
The anaphase-promoting complex or cyclosome (APC/C) is a conserved, multisubunit E3 ubiquitin (Ub) ligase that is active both in dividing and in postmitotic cells. Its contributions to life are especially well studied in the domain of cell division, in which the APC/C lies at the epicenter of a regulatory network that controls the directionality and timing of cell cycle events. Biochemical and structural work is shedding light on the overall organization of APC/C subunits and on the mechanism of substrate recognition and Ub chain initiation and extension as well as on the molecular mechanisms of a checkpoint that seizes control of APC/C activity during mitosis. Here, we review how these recent advancements are modifying our understanding of the APC/C.
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Affiliation(s)
- Ivana Primorac
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
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19
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Horikoshi Y, Habu T, Matsumoto T. An E2 enzyme Ubc11 is required for ubiquitination of Slp1/Cdc20 and spindle checkpoint silencing in fission yeast. Cell Cycle 2013; 12:961-71. [PMID: 23442800 DOI: 10.4161/cc.23946] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
For ordered mitotic progression, various proteins have to be regulated by an ubiquitin ligase, the anaphase-promoting complex or cyclosome (APC/C) with appropriate timing. Recent studies have implied that the activity of APC/C also contributes to release of mitotic checkpoint complexes (MCCs) from its target Cdc20 in the process of silencing the spindle assembly checkpoint (SAC). Here we describe a temperature-sensitive mutant (ubc11-P93L) in which cell cycle progression is arrested at mitosis. The mutant grows normally at the restrictive temperature when SAC is inactivated, suggesting that the arrest is not due to abnormal spindle assembly, but rather due to prolonged activation of SAC. Supporting this notion, MCCs remain bound to APC/C even when SAC is satisfied. The ubc11 (+) gene encodes one of the two E2 enzymes required for progression through mitosis in fission yeast. Remarkably, Slp1 (a fission yeast homolog of Cdc20), which is degraded in an APC/C-dependent manner, stays stable throughout the cell cycle in the ubc11-P93L mutant lacking the functional SAC. Other APC/C substrates, in contrast, were degraded on schedule. We have also found that a loss of Ubc4, the other E2 required for progression through mitosis, does not affect the stability of Slp1. We propose that each of the two E2 enzymes is responsible for collaborating with APC/C for a specific set of substrates, and that Ubc11 is responsible for regulating Slp1 with APC/C for silencing the SAC.
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20
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Zhang Z, Yang J, Kong EH, Chao WCH, Morris EP, da Fonseca PCA, Barford D. Recombinant expression, reconstitution and structure of human anaphase-promoting complex (APC/C). Biochem J 2013; 449:365-71. [PMID: 23078409 DOI: 10.1042/bj20121374] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Mechanistic and structural studies of large multi-subunit assemblies are greatly facilitated by their reconstitution in heterologous recombinant systems. In the present paper, we describe the generation of recombinant human APC/C (anaphase-promoting complex/cyclosome), an E3 ubiquitin ligase that regulates cell-cycle progression. Human APC/C is composed of 14 distinct proteins that assemble into a complex of at least 19 subunits with a combined molecular mass of ~1.2 MDa. We show that recombinant human APC/C is correctly assembled, as judged by its capacity to ubiquitinate the budding yeast APC/C substrate Hsl1 (histone synthetic lethal 1) dependent on the APC/C co-activator Cdh1 [Cdc (cell division cycle) 20 homologue 1], and its three-dimensional reconstruction by electron microscopy and single-particle analysis. Successful reconstitution validates the subunit composition of human APC/C. The structure of human APC/C is compatible with the Saccharomyces cerevisiae APC/C homology model, and in contrast with endogenous human APC/C, no evidence for conformational flexibility of the TPR (tetratricopeptide repeat) lobe is observed. Additional density present in the human APC/C structure, proximal to Apc3/Cdc27 of the TPR lobe, is assigned to the TPR subunit Apc7, a subunit specific to vertebrate APC/C.
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Affiliation(s)
- Ziguo Zhang
- Division of Structural Biology, Institute of Cancer Research, Chester Beatty Laboratories, 237 Fulham Road, London SW3 6JB, UK
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21
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Budhavarapu VN, White ED, Mahanic CS, Chen L, Lin FT, Lin WC. Regulation of E2F1 by APC/C Cdh1 via K11 linkage-specific ubiquitin chain formation. Cell Cycle 2012; 11:2030-8. [PMID: 22580462 DOI: 10.4161/cc.20643] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
E2F1 is a eukaryotic transcription factor that is known to regulate various cellular pathways such as cell cycle progression, DNA replication, DNA damage responses and induction of apoptosis. Given its versatile roles, a precise and tight regulation of E2F1 is very critical to maintain genomic stability. E2F1 is regulated both at transcriptional and posttranslational levels during cell cycle and upon DNA damage. After S phase, E2F1 is targeted for degradation and is kept at low levels or in an inactive state until the next G 1/S phase transition. Our studies show that APC/C ubiquitin ligase in conjunction with its co-activator Cdh1 (APC/C (Cdh1) ) can downregulate E2F1. We also identify an APC/C subunit APC5 that binds to E2F1 and is essential for E2F1 ubiquitination. We confirm an interaction between E2F1 and Cdh1 as well as an interaction between E2F1 and APC5 both in vivo and in vitro. In vitro GST pull-down assays have mapped the C-terminal 79 a.a. of E2F1 as Cdh1 interacting residues. Ectopically expressed Cdh1 downregulates the expression of E2F1-4. Our studies have also shown for the first time that E2F1 can be modified by K11-linkage specific ubiquitin chain formation (Ub-K11). The formation of Ub-K11 chains on E2F1 is increased in the presence of Cdh1 and accumulated in the presence of proteasome inhibitor, suggesting that APC/C (Cdh1) targets E2F1 for degradation by forming Ub-K11 chains. We also show that the effect of Cdh1 on E2F1 degradation is blocked upon DNA damage. Interestingly, Ub-K11-linked E2F1 accumulates after treatment of DNA damaging agents. The data suggest that DNA damage signaling processes do not inhibit APC/C (Cdh1) to ubiquitinate E2F1. Instead, they block the proteasomal degradation of Ub-K11-linked E2F1, and therefore lead to its accumulation.
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Affiliation(s)
- Varija N Budhavarapu
- Section of Hematology/Oncology, Department of Medicine, Baylor College of Medicine, Houston, TX, USA
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22
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Barford D. Structural insights into anaphase-promoting complex function and mechanism. Philos Trans R Soc Lond B Biol Sci 2012; 366:3605-24. [PMID: 22084387 DOI: 10.1098/rstb.2011.0069] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The anaphase-promoting complex or cyclosome (APC/C) controls sister chromatid segregation and the exit from mitosis by catalysing the ubiquitylation of cyclins and other cell cycle regulatory proteins. This unusually large E3 RING-cullin ubiquitin ligase is assembled from 13 different proteins. Selection of APC/C targets is controlled through recognition of short destruction motifs, predominantly the D box and KEN box. APC/C-mediated coordination of cell cycle progression is achieved through the temporal regulation of APC/C activity and substrate specificity, exerted through a combination of co-activator subunits, reversible phosphorylation and inhibitory proteins and complexes. Recent structural and biochemical studies of the APC/C are beginning to reveal an understanding of the roles of individual APC/C subunits and co-activators and how they mutually interact to mediate APC/C functions. This review focuses on the findings showing how information on the structural organization of the APC/C provides insights into the role of co-activators and core APC/C subunits in mediating substrate recognition. Mechanisms of regulating and modulating substrate recognition are discussed in the context of controlling the binding of the co-activator to the APC/C, and the accessibility and conformation of the co-activator when bound to the APC/C.
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Affiliation(s)
- David Barford
- Division of Structural Biology, Institute of Cancer Research, Chester Beatty Laboratories, 237 Fulham Road, London SW3 6JB, UK.
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23
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Abstract
In the nematode Caenorhabditis elegans, temperature-sensitive mutants of emb-1 arrest as one-cell embryos in metaphase of meiosis I in a manner that is indistinguishable from embryos that have been depleted of known subunits of the anaphase-promoting complex or cyclosome (APC/C). Here we show that the emb-1 phenotype is enhanced in double mutant combinations with known APC/C subunits and suppressed in double mutant combinations with known APC/C suppressors. In addition to its meiotic function, emb-1 is required for mitotic proliferation of the germline. These studies reveal that emb-1 encodes K10D2.4, a homolog of the small, recently discovered APC/C subunit, APC16.
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24
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Chiu PL, Kelly DF, Walz T. The use of trehalose in the preparation of specimens for molecular electron microscopy. Micron 2011; 42:762-72. [PMID: 21752659 DOI: 10.1016/j.micron.2011.06.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Revised: 06/09/2011] [Accepted: 06/10/2011] [Indexed: 11/29/2022]
Abstract
Biological specimens have to be prepared for imaging in the electron microscope in a way that preserves their native structure. Two-dimensional (2D) protein crystals to be analyzed by electron crystallography are best preserved by sugar embedding. One of the sugars often used to embed 2D crystals is trehalose, a disaccharide used by many organisms for protection against stress conditions. Sugars such as trehalose can also be added to negative staining solutions used to prepare proteins and macromolecular complexes for structural studies by single-particle electron microscopy (EM). In this review, we describe trehalose and its characteristics that make it so well suited for preparation of EM specimens and we review specimen preparation methods with a focus on the use of trehalose.
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Affiliation(s)
- Po-Lin Chiu
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
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25
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26
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Schreiber A, Stengel F, Zhang Z, Enchev RI, Kong EH, Morris EP, Robinson CV, da Fonseca PCA, Barford D. Structural basis for the subunit assembly of the anaphase-promoting complex. Nature 2011; 470:227-32. [PMID: 21307936 DOI: 10.1038/nature09756] [Citation(s) in RCA: 137] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2010] [Accepted: 12/14/2010] [Indexed: 12/18/2022]
Abstract
The anaphase-promoting complex or cyclosome (APC/C) is an unusually large E3 ubiquitin ligase responsible for regulating defined cell cycle transitions. Information on how its 13 constituent proteins are assembled, and how they interact with co-activators, substrates and regulatory proteins is limited. Here, we describe a recombinant expression system that allows the reconstitution of holo APC/C and its sub-complexes that, when combined with electron microscopy, mass spectrometry and docking of crystallographic and homology-derived coordinates, provides a precise definition of the organization and structure of all essential APC/C subunits, resulting in a pseudo-atomic model for 70% of the APC/C. A lattice-like appearance of the APC/C is generated by multiple repeat motifs of most APC/C subunits. Three conserved tetratricopeptide repeat (TPR) subunits (Cdc16, Cdc23 and Cdc27) share related superhelical homo-dimeric architectures that assemble to generate a quasi-symmetrical structure. Our structure explains how this TPR sub-complex, together with additional scaffolding subunits (Apc1, Apc4 and Apc5), coordinate the juxtaposition of the catalytic and substrate recognition module (Apc2, Apc11 and Apc10 (also known as Doc1)), and TPR-phosphorylation sites, relative to co-activator, regulatory proteins and substrates.
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Affiliation(s)
- Anne Schreiber
- Section of Structural Biology, Institute of Cancer Research, Chester Beatty Laboratories, 237 Fulham Road, London, SW3 6JB, UK
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27
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28
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McLean JR, Chaix D, Ohi MD, Gould KL. State of the APC/C: organization, function, and structure. Crit Rev Biochem Mol Biol 2011; 46:118-36. [PMID: 21261459 DOI: 10.3109/10409238.2010.541420] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The ubiquitin-proteasome protein degradation system is involved in many essential cellular processes including cell cycle regulation, cell differentiation, and the unfolded protein response. The anaphase-promoting complex/cyclosome (APC/C), an evolutionarily conserved E3 ubiquitin ligase, was discovered 15 years ago because of its pivotal role in cyclin degradation and mitotic progression. Since then, we have learned that the APC/C is a very large, complex E3 ligase composed of 13 subunits, yielding a molecular machine of approximately 1 MDa. The intricate regulation of the APC/C is mediated by the Cdc20 family of activators, pseudosubstrate inhibitors, protein kinases and phosphatases and the spindle assembly checkpoint. The large size, complexity, and dynamic nature of the APC/C represent significant obstacles toward high-resolution structural techniques; however, over the last decade, there have been a number of lower resolution APC/C structures determined using single particle electron microscopy. These structures, when combined with data generated from numerous genetic and biochemical studies, have begun to shed light on how APC/C activity is regulated. Here, we discuss the most recent developments in the APC/C field concerning structure, substrate recognition, and catalysis.
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Affiliation(s)
- Janel R McLean
- Howard Hughes Medical Institute, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
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29
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Buschhorn BA, Petzold G, Galova M, Dube P, Kraft C, Herzog F, Stark H, Peters JM. Substrate binding on the APC/C occurs between the coactivator Cdh1 and the processivity factor Doc1. Nat Struct Mol Biol 2010; 18:6-13. [PMID: 21186364 PMCID: PMC4300845 DOI: 10.1038/nsmb.1979] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Accepted: 11/17/2010] [Indexed: 12/21/2022]
Abstract
The anaphase–promoting complex/cyclosome (APC/C) is a 22 S ubiquitin ligase complex that initiates chromosome segregation and mitotic exit. We have used biochemical and electron microscopic analyses of Saccharomyces cerevisiae and human APC/C to address how the APC/C subunit Doc1 contributes to recruitment and processive ubiquitylation of APC/C substrates, and to understand how APC/C monomers interact to form a 36 S dimeric form. We show that Doc1 interacts with Cdc27, Cdc16 and Apc1, and is located in vicinity of the cullin–RING module Apc2–Apc11 in the inner cavity of the APC/C. Substrate proteins also bind in the inner cavity, in close proximity to DOC1 and the co–activator CDH1, and induce conformational changes in APC2–APC11. Our results suggest that substrates are recruited to the APC/C by binding to a bipartite substrate receptor composed of a co–activator protein and Doc1.
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Affiliation(s)
- Bettina A Buschhorn
- Research Institute of Molecular Pathology (IMP), Dr. Bohr-Gasse 7, A-1030 Vienna, Austria
| | - Georg Petzold
- Research Institute of Molecular Pathology (IMP), Dr. Bohr-Gasse 7, A-1030 Vienna, Austria
| | - Marta Galova
- Research Institute of Molecular Pathology (IMP), Dr. Bohr-Gasse 7, A-1030 Vienna, Austria
| | - Prakash Dube
- Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, D-37077 Göttingen, Germany
| | - Claudine Kraft
- Research Institute of Molecular Pathology (IMP), Dr. Bohr-Gasse 7, A-1030 Vienna, Austria
| | - Franz Herzog
- Research Institute of Molecular Pathology (IMP), Dr. Bohr-Gasse 7, A-1030 Vienna, Austria
| | - Holger Stark
- Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, D-37077 Göttingen, Germany.,Department of Molecular 3D Electron Cryomicroscopy, Institute of Microbiology and Genetics, Georg-August University Göttingen, Justus-von-Liebig Weg 11, D-37077 Göttingen, Germany
| | - Jan-Michael Peters
- Research Institute of Molecular Pathology (IMP), Dr. Bohr-Gasse 7, A-1030 Vienna, Austria
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30
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da Fonseca PCA, Kong EH, Zhang Z, Schreiber A, Williams MA, Morris EP, Barford D. Structures of APC/C(Cdh1) with substrates identify Cdh1 and Apc10 as the D-box co-receptor. Nature 2010; 470:274-8. [PMID: 21107322 PMCID: PMC3037847 DOI: 10.1038/nature09625] [Citation(s) in RCA: 162] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Accepted: 11/01/2010] [Indexed: 01/13/2023]
Abstract
The ubiquitylation of cell-cycle regulatory proteins by the large multimeric anaphase-promoting complex (APC/C) controls sister chromatid segregation and the exit from mitosis. Selection of APC/C targets is achieved through recognition of destruction motifs, predominantly the destruction (D)-box and KEN (Lys-Glu-Asn)-box. Although this process is known to involve a co-activator protein (either Cdc20 or Cdh1) together with core APC/C subunits, the structural basis for substrate recognition and ubiquitylation is not understood. Here we investigate budding yeast APC/C using single-particle electron microscopy and determine a cryo-electron microscopy map of APC/C in complex with the Cdh1 co-activator protein (APC/C(Cdh1)) bound to a D-box peptide at ∼10 Å resolution. We find that a combined catalytic and substrate-recognition module is located within the central cavity of the APC/C assembled from Cdh1, Apc10--a core APC/C subunit previously implicated in substrate recognition--and the cullin domain of Apc2. Cdh1 and Apc10, identified from difference maps, create a co-receptor for the D-box following repositioning of Cdh1 towards Apc10. Using NMR spectroscopy we demonstrate specific D-box-Apc10 interactions, consistent with a role for Apc10 in directly contributing towards D-box recognition by the APC/C(Cdh1) complex. Our results rationalize the contribution of both co-activator and core APC/C subunits to D-box recognition and provide a structural framework for understanding mechanisms of substrate recognition and catalysis by the APC/C.
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Affiliation(s)
- Paula C A da Fonseca
- Section of Structural Biology, Institute of Cancer Research, Chester Beatty Laboratories, 237 Fulham Road, London SW3 6JB, UK
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31
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Abstract
AbstractThe complex molecular events responsible for coordinating chromosome replication and segregation with cell division and growth are collectively known as the cell cycle. Progression through the cell cycle is orchestrated by the interplay between controlled protein synthesis and degradation and protein phosphorylation. Protein degradation is primarily regulated through the ubiquitin proteasome system, mediated by two related E3 protein ubiquitin ligases, the Skp1 cullin F-box (SCF) and the anaphase promoting complex (also known as the cyclosome) (APC/C). The APC/C is a multi-subunit cullin-RING E3 ubiquitin ligase that regulates progression through the mitotic phase of the cell cycle and controls entry into S phase by catalysing the ubiquitylation of cyclins and other cell cycle regulatory proteins. Selection of APC/C targets is controlled through recognition of short destruction motifs, predominantly the D-box and KEN-box. APC/C-mediated coordination of cell cycle progression is achieved through the temporal regulation of APC/C activity and substrate specificity, exerted through a combination of co-activator subunits, reversible phosphorylation and inhibitory proteins and complexes. The aim of this article is to discuss the APC/C from a structural and mechanistic perspective. Although an atomic structure of the APC/C is still lacking, a combination of genetic, biochemical, electron microscopy studies of intact APC/C and crystallographic analysis of individual subunits, together with analogies to evolutionarily related E3 ligases of the RING family, has provided deep insights into the molecular mechanisms of catalysis and substrate recognition, and structural organisation of the APC/C.
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32
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Zeng X, Sigoillot F, Gaur S, Choi S, Pfaff KL, Oh DC, Hathaway N, Dimova N, Cuny GD, King RW. Pharmacologic inhibition of the anaphase-promoting complex induces a spindle checkpoint-dependent mitotic arrest in the absence of spindle damage. Cancer Cell 2010; 18:382-95. [PMID: 20951947 PMCID: PMC2957475 DOI: 10.1016/j.ccr.2010.08.010] [Citation(s) in RCA: 242] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Revised: 07/01/2010] [Accepted: 08/10/2010] [Indexed: 12/13/2022]
Abstract
Microtubule inhibitors are important cancer drugs that induce mitotic arrest by activating the spindle assembly checkpoint (SAC), which, in turn, inhibits the ubiquitin ligase activity of the anaphase-promoting complex (APC). Here, we report a small molecule, tosyl-L-arginine methyl ester (TAME), which binds to the APC and prevents its activation by Cdc20 and Cdh1. A prodrug of TAME arrests cells in metaphase without perturbing the spindle, but nonetheless the arrest is dependent on the SAC. Metaphase arrest induced by a proteasome inhibitor is also SAC dependent, suggesting that APC-dependent proteolysis is required to inactivate the SAC. We propose that mutual antagonism between the APC and the SAC yields a positive feedback loop that amplifies the ability of TAME to induce mitotic arrest.
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Affiliation(s)
- Xing Zeng
- Department of Cell Biology, 240 Longwood Ave, Harvard Medical School, Boston, MA
| | - Frederic Sigoillot
- Department of Cell Biology, 240 Longwood Ave, Harvard Medical School, Boston, MA
| | - Shantanu Gaur
- Department of Cell Biology, 240 Longwood Ave, Harvard Medical School, Boston, MA
| | - Sungwoon Choi
- Laboratory for Drug Discovery in Neurodegeneration, Brigham & Women's Hospital and Harvard Medical School, 65 Landsdowne St, Cambridge, MA
| | - Kathleen L. Pfaff
- Department of Cell Biology, 240 Longwood Ave, Harvard Medical School, Boston, MA
| | - Dong-Chan Oh
- Department of Biological Chemistry and Molecular Pharmacology, 240 Longwood Ave, Harvard Medical School, Boston, MA
- Natural Products Research Institute, College of Pharmacy, 599 Gwanak-ro, Gwanak-gu, Seoul 151-742, Republic of Korea
| | - Nathaniel Hathaway
- Department of Cell Biology, 240 Longwood Ave, Harvard Medical School, Boston, MA
| | - Nevena Dimova
- Department of Cell Biology, 240 Longwood Ave, Harvard Medical School, Boston, MA
| | - Gregory D. Cuny
- Laboratory for Drug Discovery in Neurodegeneration, Brigham & Women's Hospital and Harvard Medical School, 65 Landsdowne St, Cambridge, MA
| | - Randall W. King
- Department of Cell Biology, 240 Longwood Ave, Harvard Medical School, Boston, MA
- Correspondence:
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The APC/C subunit Cdc16/Cut9 is a contiguous tetratricopeptide repeat superhelix with a homo-dimer interface similar to Cdc27. EMBO J 2010; 29:3733-44. [PMID: 20924356 DOI: 10.1038/emboj.2010.247] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2010] [Accepted: 09/14/2010] [Indexed: 12/20/2022] Open
Abstract
The anaphase-promoting complex/cyclosome (APC/C), an E3 ubiquitin ligase responsible for controlling cell cycle transitions, is a multisubunit complex assembled from 13 different proteins. Numerous APC/C subunits incorporate multiple copies of the tetratricopeptide repeat (TPR). Here, we report the crystal structure of Schizosaccharomyces pombe Cut9 (Cdc16/Apc6) in complex with Hcn1 (Cdc26), showing that Cdc16/Cut9 is a contiguous TPR superhelix of 14 TPR units. A C-terminal block of TPR motifs interacts with Hcn1, whereas an N-terminal TPR block mediates Cdc16/Cut9 self-association through a homotypic interface. This dimer interface is structurally related to the N-terminal dimerization domain of Cdc27, demonstrating that both Cdc16/Cut9 and Cdc27 form homo-dimers through a conserved mechanism. The acetylated N-terminal Met residue of Hcn1 is enclosed within a chamber created from the Cut9 TPR superhelix. Thus, in complex with Cdc16/Cut9, the N-acetyl-Met residue of Hcn1, a putative degron for the Doa10 E3 ubiquitin ligase, is inaccessible for Doa10 recognition, protecting Hcn1/Cdc26 from ubiquitin-dependent degradation. This finding may provide a structural explanation for a mechanism to control the stoichiometry of proteins participating in multisubunit complexes.
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34
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Zhang Z, Roe SM, Diogon M, Kong E, El Alaoui H, Barford D. Molecular structure of the N-terminal domain of the APC/C subunit Cdc27 reveals a homo-dimeric tetratricopeptide repeat architecture. J Mol Biol 2010; 397:1316-28. [PMID: 20206185 DOI: 10.1016/j.jmb.2010.02.045] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2009] [Revised: 02/19/2010] [Accepted: 02/24/2010] [Indexed: 01/20/2023]
Abstract
The anaphase promoting complex/cyclosome (APC/C) is a large multi-subunit E3 ubiquitin ligase that targets specific cell cycle regulatory proteins for ubiquitin-dependent degradation, thereby controlling cell cycle events such as the metaphase to anaphase transition and the exit from mitosis. Biochemical and genetic studies are consistent with the notion that subunits of APC/C are organised into two distinct sub-complexes; a catalytic sub-complex including the cullin domain and RING finger subunits Apc2 and Apc11, respectively, and a tetratricopeptide repeat (TPR) sub-complex composed of the TPR subunits Cdc16, Cdc23 and Cdc27 (Apc3). Here, we describe the crystal structure of the N-terminal domain of Encephalitozoon cuniculi Cdc27 (Cdc27(Nterm)), revealing a homo-dimeric structure, composed predominantly of successive TPR motifs. Mutation of the Cdc27(Nterm) dimer interface destabilises the protein, disrupts dimerisation in solution, and abolishes the capacity of E. cuniculi Cdc27 to complement Saccharomyces cerevisiae Cdc27 in vivo. These results establish the existence of functional APC/C genes in E. cuniculi, the evolutionarily conserved dimeric properties of Cdc27, and provide a framework for understanding the architecture of full-length Cdc27.
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Affiliation(s)
- Ziguo Zhang
- Section of Structural Biology, Institute of Cancer Research, Chester Beatty Laboratories, 237 Fulham Road, London SW3 6JB, UK
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35
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Matyskiela ME, Rodrigo-Brenni MC, Morgan DO. Mechanisms of ubiquitin transfer by the anaphase-promoting complex. J Biol 2010; 8:92. [PMID: 19874575 PMCID: PMC2790831 DOI: 10.1186/jbiol184] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The anaphase-promoting complex (APC) is a ubiquitin-protein ligase required for the completion of mitosis in all eukaryotes. Recent mechanistic studies reveal how this remarkable enzyme combines specificity in substrate binding with flexibility in ubiquitin transfer, thereby allowing the modification of multiple lysines on the substrate as well as specific lysines on ubiquitin itself.
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Affiliation(s)
- Mary E Matyskiela
- Department of Physiology, University of California, San Francisco, CA 94158, USA
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36
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Getting down to the phosphorylated ‘nuts and bolts’ of spindle checkpoint signalling. Trends Biochem Sci 2010; 35:18-27. [DOI: 10.1016/j.tibs.2009.09.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Revised: 09/10/2009] [Accepted: 09/11/2009] [Indexed: 12/26/2022]
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37
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Ors A, Grimaldi M, Kimata Y, Wilkinson CRM, Jones N, Yamano H. The transcription factor Atf1 binds and activates the APC/C ubiquitin ligase in fission yeast. J Biol Chem 2009; 284:23989-94. [PMID: 19584054 PMCID: PMC2781993 DOI: 10.1074/jbc.m109.018309] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2009] [Revised: 07/06/2009] [Indexed: 02/03/2023] Open
Abstract
Fission yeast Atf1 is a member of the ATF/CREB basic leucine zipper (bZIP) family of transcription factors with strong homology to mammalian ATF2. Atf1 regulates transcription in response to stress stimuli and also plays a role in controlling heterochromatin formation and recombination. However, its DNA binding independent role is poorly studied. Here, we report that Atf1 has a distinct role in regulating the anaphase-promoting complex/cyclosome (APC/C) ubiquitin ligase. We have identified atf1(+) as a dose-dependent suppressor of apc5-1, a mutation causing mitotic arrest. Remarkably, the suppression is not dependent upon the bZIP domain and is therefore independent of the ability of Atf1 to bind DNA. Interestingly, Atf1 physically binds the APC/C in vivo. Furthermore, we show that addition of purified Atf1 proteins into a cell-free system stimulates ubiquitylation of cyclin B and securin by the APC/C. These results reveal a novel role for Atf1 in cell cycle control through protein-protein interaction.
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Affiliation(s)
- Aslihan Ors
- From the Cell Cycle Control Laboratory, Marie Curie Research Institute, The Chart, Oxted, Surrey RH8 0TL, United Kingdom and
| | - Margaret Grimaldi
- From the Cell Cycle Control Laboratory, Marie Curie Research Institute, The Chart, Oxted, Surrey RH8 0TL, United Kingdom and
| | - Yuu Kimata
- From the Cell Cycle Control Laboratory, Marie Curie Research Institute, The Chart, Oxted, Surrey RH8 0TL, United Kingdom and
| | - Caroline R. M. Wilkinson
- the Cancer Research UK Cell Regulation Laboratory, Paterson Institute for Cancer Research, Manchester M20 4BX, United Kingdom
| | - Nic Jones
- the Cancer Research UK Cell Regulation Laboratory, Paterson Institute for Cancer Research, Manchester M20 4BX, United Kingdom
| | - Hiroyuki Yamano
- From the Cell Cycle Control Laboratory, Marie Curie Research Institute, The Chart, Oxted, Surrey RH8 0TL, United Kingdom and
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38
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Wang J, Dye BT, Rajashankar KR, Kurinov I, Schulman BA. Insights into anaphase promoting complex TPR subdomain assembly from a CDC26-APC6 structure. Nat Struct Mol Biol 2009; 16:987-9. [PMID: 19668213 PMCID: PMC2759704 DOI: 10.1038/nsmb.1645] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2009] [Accepted: 06/29/2009] [Indexed: 12/15/2022]
Abstract
The multi-subunit Anaphase Promoting Complex (APC) is an essential cell cycle regulator. Although CDC26 is known to play a role in APC assembly, its molecular function has remained unclear. Biophysical, structural, and genetic studies presented here reveal that CDC26 stabilizes the structure of APC6, a core TPR protein required for APC integrity. Interestingly, CDC26–APC6 association involves an intermolecular TPR mimic composed of one helix from each protein.
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Affiliation(s)
- Jing Wang
- Departments of Structural Biology and Genetics/Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
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39
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Abstract
Protein kinases are important regulators of intracellular signal transduction pathways and play critical roles in diverse cellular functions. Once a protein kinase is activated, its activity is subsequently downregulated through a variety of mechanisms. Accumulating evidence indicates that the activation of protein kinases commonly initiates their downregulation via the ubiquitin/proteasome pathway. Failure to regulate protein kinase activity or expression levels can cause human diseases.
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Affiliation(s)
- Zhimin Lu
- Department of Neuro-Oncology and Molecular and Cellular Oncology, University of Texas M. D. Anderson Cancer, Houston, TX 77030, USA.
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40
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Abstract
Single-particle electron microscopy (EM) can provide structural information for a large variety of biological molecules, ranging from small proteins to large macromolecular assemblies, without the need to produce crystals. The year 2008 has become a landmark year for single-particle EM as for the first time density maps have been produced at a resolution that made it possible to trace protein backbones or even to build atomic models. In this review, we highlight some of the recent successes achieved by single-particle EM and describe the individual steps involved in producing a density map by this technique. We also discuss some of the remaining challenges and areas, in which further advances would have a great impact on the results that can be achieved by single-particle EM.
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Affiliation(s)
- Yifan Cheng
- The W.M. Keck Advanced Microscopy Laboratory, Department of Biochemistry and Biophysics, University of California-San Francisco, CA 94158, USA.
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41
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APC/C-CCS52A complexes control meristem maintenance in the Arabidopsis root. Proc Natl Acad Sci U S A 2009; 106:11806-11. [PMID: 19553203 DOI: 10.1073/pnas.0901193106] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Plant organs originate from meristems where stem cells are maintained to produce continuously daughter cells that are the source of different cell types. The cell cycle switch gene CCS52A, a substrate specific activator of the anaphase promoting complex/cyclosome (APC/C), controls the mitotic arrest and the transition of mitotic cycles to endoreduplication (ER) cycles as part of cell differentiation. Arabidopsis, unlike other organisms, contains 2 CCS52A isoforms. Here, we show that both of them are active and regulate meristem maintenance in the root tip, although through different mechanisms. The CCS52A1 activity in the elongation zone of the root stimulates ER and mitotic exit, and contributes to the border delineation between dividing and expanding cells. In contrast, CCS52A2 acts directly in the distal region of the root meristem to control identity of the quiescent center (QC) cells and stem cell maintenance. Cell proliferation assays in roots suggest that this control involves CCS52A2 mediated repression of mitotic activity in the QC cells. The data indicate that the CCS52A genes favor a low mitotic state in different cell types of the root tip that is required for meristem maintenance, and reveal a previously undescribed mechanism for APC/C mediated control in plant development.
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42
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Matyskiela ME, Morgan DO. Analysis of activator-binding sites on the APC/C supports a cooperative substrate-binding mechanism. Mol Cell 2009; 34:68-80. [PMID: 19362536 DOI: 10.1016/j.molcel.2009.02.027] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2008] [Revised: 01/21/2009] [Accepted: 02/24/2009] [Indexed: 12/13/2022]
Abstract
The anaphase-promoting complex or cyclosome (APC/C) is a ubiquitin ligase essential for the completion of mitosis in all eukaryotic cells. Substrates are recruited to the APC/C by activator proteins (Cdc20 or Cdh1), but it is not known where substrates are bound during catalysis. We explored this problem by analyzing mutations in the tetratricopeptide-repeat-containing APC/C subunits. We identified residues in Cdc23 and Cdc27 that are required for APC/C binding to Cdc20 and Cdh1 and for APC/C function in vivo. Mutation of these sites increased the rate of activator dissociation from the APC/C but did not affect reaction processivity, suggesting that the mutations have little effect on substrate dissociation from the active site. Further studies revealed that activator dissociation from the APC/C is inhibited by substrate, and that substrates are not bound solely to activator during catalysis but interact bivalently with an additional binding site on the APC/C core.
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Affiliation(s)
- Mary E Matyskiela
- Department of Physiology, University of California, San Francisco, San Francisco, CA 94158, USA
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43
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van Leuken R, Clijsters L, van Zon W, Lim D, Yao X, Wolthuis RMF, Yaffe MB, Medema RH, van Vugt MATM. Polo-like kinase-1 controls Aurora A destruction by activating APC/C-Cdh1. PLoS One 2009; 4:e5282. [PMID: 19390576 PMCID: PMC2668763 DOI: 10.1371/journal.pone.0005282] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2008] [Accepted: 03/16/2009] [Indexed: 11/19/2022] Open
Abstract
Polo-like kinase-1 (Plk1) is activated before mitosis by Aurora A and its cofactor Bora. In mitosis, Bora is degraded in a manner dependent on Plk1 kinase activity and the E3 ubiquitin ligase SCF-betaTrCP. Here, we show that Plk1 is also required for the timely destruction of its activator Aurora A in late anaphase. It has been shown that Aurora A destruction is controlled by the auxiliary subunit Cdh1 of the Anaphase-Promoting Complex/Cyclosome (APC/C). Remarkably, we found that Plk1-depletion prevented the efficient dephosphorylation of Cdh1 during mitotic exit. Plk1 mediated its effect on Cdh1, at least in part, through direct phosphorylation of the human phosphatase Cdc14A, controlling the phosphorylation state of Cdh1. We conclude that Plk1 facilitates efficient Aurora A degradation through APC/C-Cdh1 activation after mitosis, with a potential role for hCdc14A.
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Affiliation(s)
- Renske van Leuken
- Department of Medical Oncology, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Linda Clijsters
- Division of Molecular Biology, The Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Wouter van Zon
- Division of Molecular Biology, The Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Dan Lim
- The David H. Koch Institute for Integrative Cancer Research at Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - XueBiao Yao
- University of Science and Technology, Hefei, China
| | - Rob M. F. Wolthuis
- Division of Molecular Biology, The Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Michael B. Yaffe
- The David H. Koch Institute for Integrative Cancer Research at Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - René H. Medema
- Department of Medical Oncology, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Marcel A. T. M. van Vugt
- Department of Medical Oncology, University Medical Centre Utrecht, Utrecht, the Netherlands
- The David H. Koch Institute for Integrative Cancer Research at Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Department of Medical Oncology, University Medical Center Groningen, Groningen, The Netherlands
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44
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Herzog F, Primorac I, Dube P, Lenart P, Sander B, Mechtler K, Stark H, Peters JM. Structure of the anaphase-promoting complex/cyclosome interacting with a mitotic checkpoint complex. Science 2009; 323:1477-81. [PMID: 19286556 DOI: 10.1126/science.1163300] [Citation(s) in RCA: 183] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Once all chromosomes are connected to the mitotic spindle (bioriented), anaphase is initiated by the protein ubiquitylation activity of the anaphase-promoting complex/cyclosome (APC/C) and its coactivator Cdc20 (APC/C(Cdc20)). Before chromosome biorientation, anaphase is delayed by a mitotic checkpoint complex (MCC) that inhibits APC/C(Cdc20). We used single-particle electron microscopy to obtain three-dimensional models of human APC/C in various functional states: bound to MCC, to Cdc20, or to neither (apo-APC/C). These experiments revealed that MCC associates with the Cdc20 binding site on APC/C, locks the otherwise flexible APC/C in a "closed" state, and prevents binding and ubiquitylation of a wide range of different APC/C substrates. These observations clarify the structural basis for the inhibition of APC/C by spindle checkpoint proteins.
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Affiliation(s)
- Franz Herzog
- Research Institute of Molecular Pathology, Dr. Bohr-Gasse 7, 1030 Vienna, Austria
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45
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Zhang W, Kimmel M, Spahn CMT, Penczek PA. Heterogeneity of large macromolecular complexes revealed by 3D cryo-EM variance analysis. Structure 2009; 16:1770-6. [PMID: 19081053 DOI: 10.1016/j.str.2008.10.011] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2008] [Accepted: 10/08/2008] [Indexed: 11/16/2022]
Abstract
Macromolecular structure determination by cryo-electron microscopy (EM) and single-particle analysis are based on the assumption that imaged molecules have identical structure. With the increased size of processed data sets, it becomes apparent that many complexes coexist in a mixture of conformational states or contain flexible regions. We describe an implementation of the bootstrap resampling technique that yields estimates of voxel-by-voxel variance of a structure reconstructed from the set of its projections. We introduce a highly efficient reconstruction algorithm that is based on direct Fourier inversion and that incorporates correction for the transfer function of the microscope, thus extending the resolution limits of variance estimation. We also describe a validation method to determine the number of resampled volumes required to achieve stable estimate of the variance. The proposed bootstrap method was applied to a data set of 70S ribosome complexed with tRNA and the elongation factor G. The proposed method of variance estimation opens new possibilities for single-particle analysis, by extending applicability of the technique to heterogeneous data sets of macromolecules and to complexes with significant conformational variability.
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Affiliation(s)
- Wei Zhang
- The University of Texas-Houston Medical School, Department of Biochemistry and Molecular Biology, Houston, TX 77030, USA
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46
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Abstract
Chromosome segregation in eukaryotes requires a large molecular assembly termed the kinetochore to attach chromosomes to spindle microtubules. Recent work has made substantial progress in defining the composition and activities of the kinetochore, but much remains to be learned about its macromolecular structure. This commentary discusses recent insights into structural features of the kinetochore, how these inform our understanding of its biological function, and the key challenges for the future.
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Affiliation(s)
- Julie P I Welburn
- Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, Nine Cambridge Center, Cambridge, MA 02142, USA.
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47
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Lührmann R, Stark H. Structural mapping of spliceosomes by electron microscopy. Curr Opin Struct Biol 2009; 19:96-102. [DOI: 10.1016/j.sbi.2009.01.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2008] [Revised: 01/06/2009] [Accepted: 01/07/2009] [Indexed: 10/21/2022]
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48
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Ibrahim B, Schmitt E, Dittrich P, Diekmann S. In silico study of kinetochore control, amplification, and inhibition effects in MCC assembly. Biosystems 2009; 95:35-50. [DOI: 10.1016/j.biosystems.2008.06.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2007] [Revised: 06/16/2008] [Accepted: 06/24/2008] [Indexed: 02/07/2023]
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49
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Han D, Kim K, Kim Y, Kang Y, Lee JY, Kim Y. Crystal structure of the N-terminal domain of anaphase-promoting complex subunit 7. J Biol Chem 2008; 284:15137-46. [PMID: 19091741 DOI: 10.1074/jbc.m804887200] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Anaphase-promoting complex or cyclosome (APC/C) is an unusual E3 ubiquitin ligase and an essential protein that controls mitotic progression. APC/C includes at least 13 subunits, but no structure has been determined for any tetratricopeptide repeat (TPR)-containing subunit (Apc3 and -6-8) in the TPR subcomplex of APC/C. Apc7 is a TPR-containing subunit that exists only in vertebrate APC/C. Here we report the crystal structure of quad mutant of nApc7 (N-terminal fragment, residues 1-147) of human Apc7 at a resolution of 2.5 A. The structure of nApc7 adopts a TPR-like motif and has a unique dimerization interface, although the protein does not contain the conserved TPR sequence. Based on the structure of nApc7, in addition to previous experimental findings, we proposed a putative homodimeric structure for full-length Apc7. This model suggests that TPR-containing subunits self-associate and bind to adaptors and substrates via an IR peptide in TPR-containing subunits of APC/C.
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Affiliation(s)
- Dohyun Han
- Department of Biomedical Sciences and Cancer Research Institute, Seoul National University College of Medicine, 28 Yongon-Dong, Seoul 110-799, Korea
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50
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van Leuken R, Clijsters L, Wolthuis R. To cell cycle, swing the APC/C. Biochim Biophys Acta Rev Cancer 2008; 1786:49-59. [DOI: 10.1016/j.bbcan.2008.05.002] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2008] [Revised: 05/05/2008] [Accepted: 05/13/2008] [Indexed: 11/30/2022]
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