Influence of opaque-2 and floury-2 genes on formation of proteins in particulates of corn endosperm.

Protein-rich subcellular particulates were isolated by zonal centrifugation from homogenates of endosperms of normal, opaque-2, and floury-2 mutant corn (Zea maize) kernels at different stages of development. In early stages the high lysine mutants vary from normal corn by greater production of a glutelin protein not associated with the matrix. This protein is high in lysine and may become a component of matrix glutelin at later stages of maturity. Differences in size and structure of zein-rich protein bodies were observed in the mutant strains when compared with normal corn. Enhanced production of nonmatrix glutelin as well as the reduction in synthesis of lysine-deficient zein is responsible for the improved lysine content of the mutant endosperms at early stages of development.