Light-stimulated increase of translatable mRNA for phosphoenolpyruvate carboxylase in leaves of maize.

Polyadenylated RNA has been isolated from maize leaves at various times during greening of etiolated seedlings and used to prime the wheat germ cell-free translation system. Levels of translatable messenger RNA for phosphoenolpyruvate carboxylase increase with the length of the illumination period. The pattern of the increase in translatable mRNA for the enzyme is similar to that of the increase in phosphoenolpyruvate carboxylase protein previously observed in intact tissues. Phosphoenolpyruvate carboxylase synthesized in vivo migrates as a doublet band on gradient sodium dodecyl sulfate-polyacrylamide gels. A similar doublet has been seen occasionally with the products of cell-free translation.