Components of nucleotide excision repair and DNA damage tolerance in Arabidopsis thaliana.

As obligate phototrophs, and despite shielding strategies, plants sustain DNA damage caused by UV radiation in sunlight. By inhibiting DNA replication and transcription, such damage may contribute to the detrimental effects of UV radiation on the growth, productivity, and genetic stability of higher plants. However, there is evidence that plants can reverse UV-induced DNA damage by photoreactivation or remove it via nucleotide excision repair. In addition, plants may have mechanisms for tolerating UV photoproducts as a means of avoiding replicative arrest. Recently, phenotypic characterization of plant mutants, functional complementation studies, and cDNA analysis have implicated genes isolated from the model plant Arabidopsis thaliana in nucleotide excision repair or tolerance of UV-induced DNA damage. Here, we briefly review features of these processes in human cells, collate information on Arabidopsis homologs of the relevant genes, and summarize the experimental findings that link certain of these plant genes to nucleotide excision repair or damage tolerance.