Reactome: A Curated Pathway Database

Insertion of correct bases opposite the lesion by POLH (R-HSA-110317) [Homo sapiens]


DNA polymerase eta (POLH) correctly incorporates two adenine deoxyribonucleotides (dAMPs) opposite a TT-CPD (thymine-thymine cyclobutane pyrimidine dimer) lesion. POLH can bypass other types of lesions, such as AP sites and cisplatin-induced intrastrand cross-linked gunanines, preferentially incorporating dAMPs and dGMPs opposite the lesion. While POLH is accurate in translesion synthesis (TLS) across thymine dimers, POLH has a low fidelity in TLS across other DNA damage types and when copying undamaged DNA. One of the protective mechanisms against POLH-induced mutagenesis may be that POLH cannot continue chain elongation after an incorrect nucleotide is incorporated (Matsuda et al. 2000, Masutani et al. 2000).

Additional Information
Compartment nucleoplasm
Literature References
pubMedId Title Journal Year
10801132 Low fidelity DNA synthesis by human DNA polymerase-eta Nature 2000
10856253 Mechanisms of accurate translesion synthesis by human DNA polymerase eta. EMBO J 2000