The events of the cell cycle are coordinated by feedback controls that ensure that cells do not enter mitosis unless their DNA has been replicated and do not leave mitosis unless a mitotic spindle has been correctly assembled. This proposal describes biochemical and genetic strategies to elucidate the molecular mechanism of cell cycle feedback control. The biochemical approach will use extracts of frog eggs which perform the cell cycle in vitro and lack detectable feedback controls. These extracts will be used as an assay system to purify and determine the mode of action of a prototypic feedback regulator, cytostatic factor (CSF), which arrests unfertilized frog eggs in meiosis be preventing the degradation of the cell cycle regulatory protein cyclin. CSF is inactivated at fertilization. The mechanism of CSF inactivation will also be investigated by examining the ability of somatic cell extracts to arrest the embryonic cell cycle has been arrested with inhibitors of DNA synthesis or spindle assembly will be tested for their ability to arrest the progress of in vitro cell cycle extracts. This complementation assay will be used to purify and characterize the components of cell cycle feedback control in somatic cells. Feedback control mutants that allow cells which have not completed DNA replication to enter mitosis will be isolated in budding yeast. These mutants will be characterized both genetically and biochemically. The study of cell cycle feedback controls is relevant to important medical problems. Failure of these controls leads to chromosome loss and breakage, causative events of some birth defects and cancers. Selective suppression of feedback controls in cancer cells could increase the power of chemotherapy.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
1R01GM043987-01
Application #
3303142
Study Section
Molecular Cytology Study Section (CTY)
Project Start
1990-04-01
Project End
1995-03-31
Budget Start
1990-04-01
Budget End
1991-03-31
Support Year
1
Fiscal Year
1990
Total Cost
Indirect Cost
Name
University of California San Francisco
Department
Type
Schools of Medicine
DUNS #
073133571
City
San Francisco
State
CA
Country
United States
Zip Code
94143
Barber, Felix; Ho, Po-Yi; Murray, Andrew W et al. (2017) Details Matter: Noise and Model Structure Set the Relationship between Cell Size and Cell Cycle Timing. Front Cell Dev Biol 5:92
Nannas, Natalie J; O'Toole, Eileen T; Winey, Mark et al. (2014) Chromosomal attachments set length and microtubule number in the Saccharomyces cerevisiae mitotic spindle. Mol Biol Cell 25:4034-48
Nannas, Natalie J; Murray, Andrew W (2014) Tethering sister centromeres to each other suggests the spindle checkpoint detects stretch within the kinetochore. PLoS Genet 10:e1004492
Hyland, Edel M; Wallace, Edward W J; Murray, Andrew W (2014) A model for the evolution of biological specificity: a cross-reacting DNA-binding protein causes plasmid incompatibility. J Bacteriol 196:3002-11
Lau, Derek T C; Murray, Andrew W (2012) Mad2 and Mad3 cooperate to arrest budding yeast in mitosis. Curr Biol 22:180-90
Nannas, Natalie J; Murray, Andrew W (2012) Complications dawn for kinetochore regulation by Aurora. Proc Natl Acad Sci U S A 109:15972-3
Murray, Andrew W (2012) Don't make me mad, Bub! Dev Cell 22:1123-5
Lang, Gregory I; Murray, Andrew W (2011) Mutation rates across budding yeast chromosome VI are correlated with replication timing. Genome Biol Evol 3:799-811
Barnhart, Erin L; Dorer, Russell K; Murray, Andrew W et al. (2011) Reduced Mad2 expression keeps relaxed kinetochores from arresting budding yeast in mitosis. Mol Biol Cell 22:2448-57
Elez, Marina; Murray, Andrew W; Bi, Li-Jun et al. (2010) Seeing mutations in living cells. Curr Biol 20:1432-7

Showing the most recent 10 out of 13 publications