To evaluate the functional significance of human BRCA1 and BRCA2 variants and to carry out functional dissection of these proteins, we have developed a simple, reliable and physiologically relevant functional assay using mouse embryonic stem (ES) cells. The assay is based on the fact that Brca1 and Brca2-null ES cells cannot survive. Therefore we engineered ES cells to express a conditional allele of Brca1 or Brca2. Desired mutations are generated in the human BRCA1 or BRCA2 gene in bacterial artificial chromosomes (BAC) and introduced into the ES cells. Functional analysis is performed after deletion of the conditional allele. The ability of and the extent to which specific variants complement the lethality of ES cells associated with Brca1 or Brca2 deficiency is used to evaluate their functional significance. Variants that can rescue lethality are then screened for a defect in the known functions of BRCA1 and BRCA2.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Investigator-Initiated Intramural Research Projects (ZIA)
Project #
1ZIABC011181-04
Application #
8553023
Study Section
Project Start
Project End
Budget Start
Budget End
Support Year
4
Fiscal Year
2012
Total Cost
$659,502
Indirect Cost
Name
National Cancer Institute Division of Basic Sciences
Department
Type
DUNS #
City
State
Country
Zip Code
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Biswas, Kajal; Stauffer, Stacey; Sharan, Shyam K (2012) Using recombineering to generate point mutations:galK-based positive-negative selection method. Methods Mol Biol 852:121-31
Chang, Suhwan; Stauffer, Stacey; Sharan, Shyam K (2012) Using recombineering to generate point mutations: the oligonucleotide-based "hit and fix" method. Methods Mol Biol 852:111-20
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Kuznetsov, Sergey G; Liu, Pentao; Sharan, Shyam K (2008) Mouse embryonic stem cell-based functional assay to evaluate mutations in BRCA2. Nat Med 14:875-81