The goal of our research program is to understand how exit from mitosis is regulated in vertebrate cells and how this process is disrupted in cancer cells. Progression through the eukaryotic cell cycle is controlled by carefully timed protein phosphorylation and protein degradation. Anaphase and mitotic exit depend on the ubiquitin-dependent degradation of regulators such as securins and mitotic cyclins. These proteins are targeted for ubiquitination by a multisubunit ubiquitin ligase called the Anaphase-Promoting Complex or Cyclosome (APC). Our goal is to study how APC is controlled in vertebrate cells by finding chemicals that affect the regulation or activity of this complex. We have identified several compounds that stabilize cyclin B in Xenopus egg extracts and block exit from mitosis through a novel mechanism. Our goal is to identify the protein targets of these inhibitors using a combination of biochemical characterization and affinity-based techniques. We have also identified a compound that directly inhibits the activity of the APC in vitro, and we will use this compound to study APC regulation in cells. One of the mitotic inhibitors discovered in our Xenopus cell cycle screen paradoxically increases the rate at which cells exit mitosis in the presence of taxol. We will use this inhibitor to study the mechanism by which cells undergo this adaptation process. Understanding how exit from mitosis and adaptation is regulated will provide important insights for understanding how cancer cells respond to taxol treatment.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
1R01GM066492-01
Application #
6465415
Study Section
Cell Development and Function Integrated Review Group (CDF)
Program Officer
Zatz, Marion M
Project Start
2002-05-01
Project End
2007-04-30
Budget Start
2002-05-01
Budget End
2003-04-30
Support Year
1
Fiscal Year
2002
Total Cost
$323,840
Indirect Cost
Name
Harvard University
Department
Anatomy/Cell Biology
Type
Schools of Medicine
DUNS #
082359691
City
Boston
State
MA
Country
United States
Zip Code
02115
Boselli, Monica; Lee, Byung-Hoon; Robert, Jessica et al. (2017) An inhibitor of the proteasomal deubiquitinating enzyme USP14 induces tau elimination in cultured neurons. J Biol Chem 292:19209-19225
Lee, Byung-Hoon; Lu, Ying; Prado, Miguel A et al. (2016) USP14 deubiquitinates proteasome-bound substrates that are ubiquitinated at multiple sites. Nature 532:398-401
Lub, Susanne; Maes, Anke; Maes, Ken et al. (2016) Inhibiting the anaphase promoting complex/cyclosome induces a metaphase arrest and cell death in multiple myeloma cells. Oncotarget 7:4062-76
Lu, Ying; Lee, Byung-hoon; King, Randall W et al. (2015) Substrate degradation by the proteasome: a single-molecule kinetic analysis. Science 348:1250834
de Lange, Job; Faramarz, Atiq; Oostra, Anneke B et al. (2015) Defective sister chromatid cohesion is synthetically lethal with impaired APC/C function. Nat Commun 6:8399
Sackton, Katharine L; Dimova, Nevena; Zeng, Xing et al. (2014) Synergistic blockade of mitotic exit by two chemical inhibitors of the APC/C. Nature 514:646-9
King, Randall W; Finley, Daniel (2014) Sculpting the proteome with small molecules. Nat Chem Biol 10:870-4
Lim, Hui-Jun; Dimova, Nevena V; Tan, Meng-Kwang Marcus et al. (2013) The G2/M regulator histone demethylase PHF8 is targeted for degradation by the anaphase-promoting complex containing CDC20. Mol Cell Biol 33:4166-80
Pfaff, Kathleen L; King, Randall W (2013) Determinants of human cyclin B1 association with mitotic chromosomes. PLoS One 8:e59169
Sigoillot, Frederic D; Lyman, Susan; Huckins, Jeremy F et al. (2012) A bioinformatics method identifies prominent off-targeted transcripts in RNAi screens. Nat Methods 9:363-6

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