Mutants defective in the normal cell cycle of yeast have been identified, some of which arrest with a nuclear division defect. Mutations in the CDC48 gene are conditionally defective in completing the segregation of mother and daughter nuclei, after normal migration of the nucleus into the bud-neck has occurred. Membranes isolated from mutant strains possess an in vitro defect in the fusion of nuclear membranes, as would be required for completion of nuclear fission. Biochemical evidence supports the idea that Cdc48 protein participates in membrane fusion events involving the nuclear envelope and endoplasmic reticulum. The proposed study will investigate the role of Cdc48p in nuclear envelope membrane fusion. Genetic and biochemical methodologies will be employed to investigate the mechanism of Cdc48p action during membrane fusion and to identify components that interact with Cdc48p. Subsequent analysis of Cdc48p interactors in biochemical assays will reveal if they act upstream of Cdc48p, such as cell cycle specific modulators, or if they are substrates of Cdc48p, such as proteins involved in the fusion of lipid bilayers. It is anticipated that many of these proteins will be needed for the fusion of endoplasmic reticulum membranes and thus mitosis.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM054729-04
Application #
6181238
Study Section
Molecular Cytology Study Section (CTY)
Program Officer
Shapiro, Bert I
Project Start
1997-05-01
Project End
2000-11-30
Budget Start
2000-05-01
Budget End
2000-11-30
Support Year
4
Fiscal Year
2000
Total Cost
$112,360
Indirect Cost
Name
Salk Institute for Biological Studies
Department
Type
DUNS #
078731668
City
La Jolla
State
CA
Country
United States
Zip Code
92037
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Rouiller, I; Butel, V M; Latterich, M et al. (2000) A major conformational change in p97 AAA ATPase upon ATP binding. Mol Cell 6:1485-90