AtREV3 induces mutations in Arabidopsis

Nakagawa, Mayu; Sakamoto, Ayako; Takahashi, Shinya*; Tanaka, Atsushi; Narumi, Issei

Plants were exposed to the various DNA-damaging stress in daily life. To survive in such hostile environments, plants developed many mechanisms to avoid or to repair the DNA damage. Yeast and mammals have a mechanism named translesion syntheses (TLS), in which DNA damage is bypassed by specific DNA polymerases. However, TLS generates mutations as a result of incorrect replication (error-prone TLS). We have previously isolated AtREV3, AtREV1 and AtREV7 genes, which are homolog of yeast TLS polymerases. We also showed that disruption of these genes made the plants sensitive to UV-B, -ray and MMC. To determine whether AtREV3 acts in the error-prone TLS, we utilized the beta-glucuronidase (uidA) gene containing single nonsense mutations. Transgenic plants with inactivated uidA were treated with UV-C and reversion events were counted. As a result, mutation frequency was reduced in the rev3 background, indicating that AtREV3 acts in the error-prone TLS in Arabidopsis.