This is a family of proteins which regulate replication of rolling circle replication (RCR) plasmids that have a double-strand replication origin (dso). Regulation of replication of RCR plasmids occurs mainly at initiation of leading strand synthesis at the dso, such that Rep protein concentration controls plasmid replication [1].

1: Rolling-circle replication of bacterial plasmids. Khan SA; Microbiol Mol Biol Rev. 1997;61:442-455. PMID:9409148