This entry includes Rad18 from eukaryotes. Rad18 is a E3 ubiquitin ligase required for postreplication repair []. In budding yeast, Rad18 forms a heterodimer with Rad6 to monoubiquitinate PCNA at a highly conserved lysine, 'Lys-164' []. In humans, Rad18 associates to the E2 ubiquitin conjugating enzyme UBE2B to form the UBE2B-RAD18 ubiquitin ligase complex involved in mono-ubiquitination of DNA-associated PCNA on 'Lys-164' [].
