EFFECT OF priA like GENE MUTATION ON DNA REPAIR AND DNA TRANSFORMATION OF Deinococcus radiodurans

WANG Yuan HUA Yue-jin(Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province/ Institute of Nuclear-Agricultural Sciences,Zhejiang University,Zhejiang,Hangzhou 310029)

priA;Deinococcus radioduans;DNA repair;DNA transformation efficiency

Replication fork progression can be blocked easily by DNA damage.Damaged DNA repair and the subsequent restart of the stalled or collapsed replication forks are critical for cell survival.The PriA-dependent pathway is the major replication restart mechanism in bacteria.To understand the roles of a priA-like gene(Dr2606) in Deinococcus radiodurans and DNA repair,a Dr2606 null mutant was constructed by replacing Dr2606 open reading frame with a kanamycin-resistance gene and treated the Dr2606 mutant with UV and mitomycin C(MMC),and the DNA transformation efficiency of the Dr2606 mutant was also tested.Successively,the Dr2606 mutant showed a delayed growth and a dramatic decrease of cell viability.Unexpectedly,the DNA repair capability of D.radiodurans was not impaired by the inactivation of Dr2606.However,the DNA transformation efficiency was largely compromised in the mutant.These results indicate that the priA-like gene(Dr2606) is dispensable for stalled DNA replication forks restart in D.radiodurans and origin-independent replication restart in D.radiodurans may be different from other bacteria.