In recent years, nuclear fusion has been the focus of intense study. In yeast, nuclear envelope does not break down at any stage of the cell cycle or during mating. One essential factor for nuclear membrane fusion is Kar5p. The Kar5p protein is localized near the spindle pole body (SPB), where the fusion is initiated. Since it is the only known fusion factor associated with the SPB, it likely controls and/or promotes the fusion process. Consistent with this, I generated a number of kar5 alleles that are mislocalized and also, display a dominant-negative phenotype. Our current model is that Kar5p directs the other fusion factors specifically to the SPB. Interestingly, Kar5p is likely to function in mitotic cells. Since all the other fusion factors have roles in mitotic cells, it is reasonable to assume that Kar5p does the same. This research proposal outlines several molecular and genetic approaches to elucidate the role(s) of Kar5p in mating and mitotic cells. The function(s) of Kar5p are likely to be conserved since its homolog in fission yeast is also required for nuclear fusion. Furthermore, since homotypic membrane fusion occurs in all eukaryotic organisms, this study is of general interest for all fusion processes.
Specific aims are (I) to test whether Kar5p is involved candidate pathways; (II) to identify its interacting factors; (III) to determine its mitotic function.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Postdoctoral Individual National Research Service Award (F32)
Project #
1F32GM020342-01A1
Application #
6208498
Study Section
Cell Development and Function Integrated Review Group (CDF)
Program Officer
Tompkins, Laurie
Project Start
2001-02-01
Project End
Budget Start
2001-02-01
Budget End
2001-08-31
Support Year
1
Fiscal Year
2001
Total Cost
$23,681
Indirect Cost
Name
Princeton University
Department
Biochemistry
Type
Schools of Arts and Sciences
DUNS #
002484665
City
Princeton
State
NJ
Country
United States
Zip Code
08544
Erdeniz, Naz; Dudley, Sandra; Gealy, Regan et al. (2005) Novel PMS1 alleles preferentially affect the repair of primer strand loops during DNA replication. Mol Cell Biol 25:9221-31