Abstract
In order to understand UVB resistant mechanisms in higher plants, we have induced UVB resistant/ sensitive mutants by means of ion beams as a new mutagen. Analysis of rev3 and subsequent rev1 and rev7 mutants first indicate the existence of translesion synthesis (TLS) mechanisms in plants. Induction of UVB super resistant mutants, uvi1 and uvi4, suggest that regulation of DNA repair and endreduplication of DNA in a cell could increase resistance to UVB as a member of solar radiation. These results suggest that UVB resistance in Arabidopsis include a lot of known and unknown mechanisms, which are closely related with cell cycle, tissue and organ, and plant growth.
