E. Miadokova et al., EFFECTS OF CAFFEINE AND ARG7 LOCUS ON MUTABILITY OF UV-TREATED PHOTOREACTIVATION-DEFICIENT MUTANTS OF CHLAMYDOMONAS-REINHARDTII, Biologia plantarum, 36(1), 1994, pp. 47-52
Forward streptomycin-resistant mutations and reverse mutations at the
ARG7 locus after UV irradiation were studied in two photoreactivation-
deficient mutants of Chlamydomonas reinhardtii, Phr1 and Phr2. The mut
ant Phr1 was more mutable than Phr2. Caffeine increased survival and r
educed mutation rate of streptomycin-resistant mutations induced in bo
th photoreactivation-deficient strains. Two different alleles of ARG7
locus (arg2 and arg7) were introduced into photoreactivation-deficient
mutants. It was found that in the presence of both alleles, the frequ
ency of mutants resistant to streptomycin was reduced. The reduction w
as more remarkable in the presence of arg2. But also under these condi
tions Phr1 was more mutable than Phr2.