Synthesis and assembly of ribulosebisphosphate carboxylase enzyme during greening of barley plants

The synthesis and activation of ribulosebisphosphate carboxylase was studied in etiolated barley leaves during increasing periods of light irradiation. Comparisons were made among enzymatic activity, ¹⁴C-amino acid incorporation into anti-ribulosebisphosphate carboxylase precipitable and 16S protein, and total mass of enzyme. A major portion of newly synthesized anti-ribulosebisphosphate carboxylase specific protein preceded light-induced increase in enzyme activity by a significant period of time. These findings are consistent with a model in which both subunits of ribulosebisphosphate carboxylase are synthesized in response to an early event in greening and subsequently become associated to active oligomeric carboxylase species.