Oligonucleotide/Oligosaccharide Binding Fold Containing Protein 1 (OBFC1)

OBFC1 and C17ORF68 are subunits of an alpha accessory factor (AAF) that stimulates the activity of DNA polymerase-alpha-primase, the enzyme that initiates DNA replication. OBFC1 also appears to function in a telomere-associated complex with C17ORF68 and TEN1.

The human AAF44 protein shares 71% identity with mouse Aaf44, with highest conservation in the OB fold domain. Northern blot analysis detected low and variable Aaf44 expression in several mouse tissues. Endogenous Aaf44 protein had an apparent molecular mass of 44 kD by SDS-PAGE. Aaf44 and Aaf132 colocalized in nuclei of transfected synchronized HeLa cells, with exclusion from nucleoli. The 2 proteins colocalized with PCNA, presumably within DNA replication foci.