Primase, DNA Polypeptide 2 (PRIM2)

DNA replication in human cells is initiated by a complex apparatus containing a DNA polymerase-alpha/primase complex that is well conserved from yeast to human. The DNA polymerase-alpha/primase complex contains 4 subunits: the polymerase-alpha p180 (POLA) and p68 (POLA2) subunits, and the primase p58 (PRIM2A) and p49 (PRIM1) subunits. Primase synthesizes oligoribonucleotides that serve as primers for the initiation of DNA synthesis. It plays a role in both the initiation of DNA replication and the synthesis of Okazaki fragments for lagging strand synthesis.

The deduced 446-amino acid protein shares 89% identity with mouse p58, with 5 regions of homology distributed over the central part of the protein. The N and C termini are less well conserved.