Plays an essential role in several cellular processes in DNA metabolism including replication,recombination and DNA repair.Binds and subsequently stabilizes single-stranded DNA intermediates and thus prevents complementary DNA from reannealing.Functions as component of the alternative replication protein A complex (aRPA).aRPA binds single-stranded DNA and probably plays a role in DNA repair;it does not support chromosomal DNA replication and cell cycle progression through S-phase.In vitro,aRPA cannot promote efficient priming by DNA polymerase alpha but supports DNA polymerase delta synthesis in the presence of PCNA and replication factor C (RFC),the dual incision/excision reaction of nucleotide excision repair and RAD51-dependent strand exchange.