DNA is duplicated and packaged to ensure that a complete genome is transmitted to each daughter cell. Two types of packaging, sister chromatid cohesion and condensation are essential for proper chromosome segregation. Budding yeast proteins Pds5p and Mcdlp are essential for both cohesion and condensation. Our long-term goal is use Pds5p and Mcdlp as tools to elucidate the molecular mechanism responsible for sister chromatid cohesion and to examine the role that cohesion plays in condensation and the maintenance of genetic stability. These studies will investigate how Pds5p and Mcd1p bind to chromosomes and to other chromosomal proteins to create functional mitotic chromosome& PCR will be use to identify the specific DNA sequences that specify where the sites of cohesion axe formed and how there are regulated. Fluorescence in situ hybridization (FISH) will be used to examine the nature of the connection between cohesion and condensation by assessing how mutants in cohesion distort chromosome structure. The types of genetic instability generated by mutations in pds5 and mcd1 will be quantified by measuring unequal sister chromatid recombination and sensitivity to DNA damaging agents. Homologs for cohesion and condensation proteins are found in all eukaryotes which makes the study of these yeast genes relevant for understanding mitotic chromosome structure and segregation in humans. Genetic instability is a hallmark of cancer cells. Cellular defects in the DNA repair machinery and in checkpoints are known to lead to such instability and contribute to tumorigenesis. Cellular defects in the machinery that forms and modulates chromosome structure represent potentially important and uncharacterized risk factors for cancer as well as a novel targets for anti-cancer therapy.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM062178-05
Application #
6837164
Study Section
Cell Development and Function Integrated Review Group (CDF)
Program Officer
Carter, Anthony D
Project Start
2001-02-01
Project End
2006-02-03
Budget Start
2005-02-01
Budget End
2006-02-03
Support Year
5
Fiscal Year
2005
Total Cost
$237,587
Indirect Cost
Name
Institute for Cancer Research
Department
Type
DUNS #
064367329
City
Philadelphia
State
PA
Country
United States
Zip Code
19111
Cooper, Katrina F; Mallory, Michael J; Guacci, Vincent et al. (2009) Pds1p is required for meiotic recombination and prophase I progression in Saccharomyces cerevisiae. Genetics 181:65-79
Guacci, Vincent (2007) Sister chromatid cohesion: the cohesin cleavage model does not ring true. Genes Cells 12:693-708
Aguilar, Cristina; Davidson, Christian; Dix, Melissa et al. (2005) Topoisomerase II suppresses the temperature sensitivity of Saccharomyces cerevisiae pds5 mutants, but not the defect in sister chromatid cohesion. Cell Cycle 4:1294-304
Stead, Kristen; Aguilar, Cristina; Hartman, Theresa et al. (2003) Pds5p regulates the maintenance of sister chromatid cohesion and is sumoylated to promote the dissolution of cohesion. J Cell Biol 163:729-41