May play an essential role at the early stage of chromosomal DNA replication by coupling the polymerase alpha/primase complex to the cellular replication machinery. DNA polymerase alpha:primase is a four subunit enzyme complex, which is assembled throughout the cell cycle, and consists of the two DNA polymerase subunits A and B, and the DNA primase large and small subunits. Subunit B binds to subunit A (By similarity). Belongs to the DNA polymerase alpha subunit B family.