Evidence for autoregulation of cystathionine γ-synthase mRNA stability in Arabidopsis

Control of messenger RNA (mRNA) stability serves as an important mechanism, for regulating gene expression. Analysis of Arabidopsis mutants that overaccumulate soluble methionine (Met) revealed that the gene for cystathionine gamma-synthase (CCS), the key enzyme in Met biosynthesis, is regulated at the Level of mRNA stability, Transfection experiments with wild-type and mutant forms of the CCS gene suggest that an amino acid sequence encoded by the first exon of CCS acts in cis to destabilize its own mRNA in a process that is activated by Met or one of its metabolites.