DNA polymerase alpha

The DNA polymerase alpha complex consists of 4 subunits: POLA1, POLA2, PRIM1, and PRIM2.

[2] Pol α has limited processivity and lacks 3′ exonuclease activity for proofreading errors.

Thus it is not well suited to efficiently and accurately copy long templates (unlike Pol Delta and Epsilon).

Pol α is responsible for the initiation of DNA replication at origins of replication (on both the leading and lagging strands) and during synthesis of Okazaki fragments on the lagging strand.

[3] This article incorporates text from the United States National Library of Medicine, which is in the public domain.