InterPro domain: IPR022880

DNA polymerase IV is a poorly processive, error-prone DNA polymerase involved in untargeted mutagenesis. It copies undamaged DNA at stalled replication forks, which arise in vivo from mismatched or misaligned primer ends. These misaligned primers can be extended by polIV. It exhibits no 3'-5' exonuclease (proofreading) activity and may be involved in translesional synthesis [ 1 , 2 , 3 , 4 , 5 ].

1. Multiple pathways for SOS-induced mutagenesis in Escherichia coli: an overexpression of dinB/dinP results in strongly enhancing mutagenesis in the absence of any exogenous treatment to damage DNA. Proc. Natl. Acad. Sci. U.S.A. 94, 13792-7
2. All three SOS-inducible DNA polymerases (Pol II, Pol IV and Pol V) are involved in induced mutagenesis. EMBO J. 19, 6259-65
3. SOS mutator DNA polymerase IV functions in adaptive mutation and not adaptive amplification. Mol. Cell 7, 571-9
4. The processivity factor beta controls DNA polymerase IV traffic during spontaneous mutagenesis and translesion synthesis in vivo. EMBO Rep. 3, 45-9
5. SOS-induced DNA polymerases enhance long-term survival and evolutionary fitness. Proc. Natl. Acad. Sci. U.S.A. 99, 8737-41