SUMMARY PARAGRAPH for REV3
REV3 and REV7 are involved in translesion synthesis during post-replication repair and double-strand break repair (4, 7). REV3 and REV7 encode the subunits of DNA polymerase zeta; Rev3p is the catalytic subunit whose activity is stimulated by Rev7p (8). In addition to their role in translesion synthesis, Rev3p and Rev7p are involved in double-strand break repair (9).
Pol zeta is an inefficient DNA polymerase; it has low fidelity and processivity when incorporating nucleotides across from damaged and undamaged base pairs (8, 10, 11, 12, 4). However, it cooperates with different DNA polymerases, such as Rev1p, pol eta (encoded by RAD30), and the catalytic subunit of pol delta (encoded by POL3), to allow efficient DNA synthesis from the termini of mispaired nucleotides (13, 14, 15, 4). This process can be error-free or error-prone depending on the damaged nucleotide and the inserted nucleotide (reviewed in 4). However, REV3 and REV7 are primarily considered to be in an error-prone translesion pathway due to a decrease in mutation frequency in their absence (1, 16, 17).
REV3 and REV7 are also implicated in double-strand break repair (5). A rev3 mutant has lower levels of mutations associated with homologous recombination events (18). The Rev1p-polzeta complex localizes to double-strand break sites (9).
Pol zeta is widely conserved (7). Rev3p is a member of the B-family of DNA polymerases, which include polymerases alpha, delta, and epilson (4). Rev7p contains a HORMA domain that is found in proteins involved in cell-cycle control, meiosis, and DNA repair (19).
Last updated: 2010-02-02