Critical functions of Rpa3/Ssb3 in S-phase DNA damage responses in fission yeast.

ABSTRACT: Replication Protein A (RPA) is a heterotrimeric, single-stranded DNA (ssDNA)-binding complex required for DNA replication and repair, homologous recombination, DNA damage checkpoint signaling, and telomere maintenance. Whilst the larger RPA subunits, Rpa1 and Rpa2, have essential interactions with ssDNA, the molecular functions of the smallest subunit Rpa3 are unknown. Here, we investigate the Rpa3 ortholog Ssb3 in Schizosaccharomyces pombe and find that it is dispensable for cell viability, checkpoint signaling, RPA foci formation, and meiosis. However, increased spontaneous Rad11Rpa1 and Rad22Rad52 nuclear foci in ssb3Δ cells indicate genome maintenance defects. Moreover, Ssb3 is required for resistance to genotoxins that disrupt DNA replication. Genetic interaction studies indicate that

SUBMITTER: Cavero S 

PROVIDER: S-EPMC2944793 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature