Structural highlights
Function
DPO4_CALS4 Poorly processive, error-prone DNA polymerase involved in translesion repair and untargeted mutagenesis. 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. Exhibits no 3'-5' exonuclease (proofreading) activity (By similarity). Involved in translesional synthesis. Primer extension fidelity in vitro is temperature-dependent. Inserts a correct base opposite templating bases at 70 degrees Celsius, but at 37 degrees Celsius in addition to correct base pairing, base transitions, transversions and frameshifts can occur. Preferably forms erroneous base pairs C:T. Bypasses 8-oxo-dG oxidative damage by incorporating dATP or dCTP opposite of the damaged DNA template site at both temperatures in vitro (PubMed:37683741).[UniProtKB:Q47155][HAMAP-Rule:MF_01113][1]
References
- ↑ Tian LF, Gao H, Yang S, Liu YP, Li M, Xu W, Yan XX. Structure and function of extreme TLS DNA polymerase TTEDbh from Thermoanaerobacter tengcongensis. Int J Biol Macromol. 2023 Dec 31;253(Pt 2):126770. PMID:37683741 doi:10.1016/j.ijbiomac.2023.126770