alpha DNA polymerase:primase complex A complex of four polypeptides, comprising large and small DNA polymerase alpha subunits and two primase subunits, which catalyzes the synthesis of an RNA primer on the lagging strand of replicating DNA; the smaller of the two primase subunits alone can catalyze oligoribonucleotide synthesis. DNA polymerase alpha:primase complex GO:0005658 cellular_component go.owl heterotetrameric polymerase alpha holoenzyme pol-prim primosome pro.owl nuclear chromosome part nuclear DNA-directed RNA polymerase complex