UV-induction of chalcone synthase mRNA in cell suspension cultures of Petroselinum hortense.

DNAs complementary to poly(A)(+) mRNAs from UV-irradiated cell suspension cultures of parsley (Petroselinum hortense) were inserted into pBR322 and used to transform Escherichia coli strain RR1. A clone containing a DNA complementary to chalcone synthase mRNA was identified by hybrid-selected and hybrid-arrested translation. Large and rapid changes in the amount of chalcone synthase mRNA in response to irradiation of the cells was detected by RNA blot hybridization experiments. The pattern of changes coincided with that previously determined for the rate of chalcone synthase synthesis as measured either in vivo or with polyribosomal mRNA in vitro. The results are consistent with the hypothesis that induction of chalcone synthase by UV light is due to a transient increase in the rate of synthesis of chalcone synthase mRNA.