Abstract
The BRCA1 is associated with hereditary breast cancer and functions in maintenance of genome stability. The BRCA1 is one of major downstream targets of ATM phosphorylation in response to DNA damage, and the phosphorylated BRCA1 functions as a regulator of further downstream proteins involved in DNA repair. The BRCA1 gene has been identified from mammals, but not from yeast and insects. Interestingly the Arabidopsis genome possesses a counterpart gene of BRCA1 (AtBRCA1). The expression of AtBRCA1 was drastically induced by gamma-irradiation, and this induction was dependent on ATM.
To study the function of BRCA1 in higher plants, we analyzed AtBRCA1 deficient mutants. The mutants showed higher sensitivity to DNA damaging agents. The reduced frequency of intra-chromosomal recombination was also observed in the mutants under genotoxic stress conditions. We are currently performing transcriptome analyses with atbrca1 plants to identify downstream genes that are regulated by AtBRCA1.
