Biochemical analysis of wild-type and fl4 endosperm. A, Comparison of zein, nonzein, and total proteins from wild-type (WT) and fl4 mature endosperm. The measurements were done on per milligram of dried endosperm. Values are the mean values with se (n = three individuals; *P < 0.05, **P < 0.01, Student’s t test). B, SDS-PAGE analysis of total proteins from wild-type and fl4 mature endosperm. C, The soluble amino acids with different content in wild-type and fl4 mature endosperm. Values are the mean values with se (n = three individuals; *P < 0.05, **P < 0.01, ***P < 0.001, Student’s t test). D, Comparison of total starch content and the percentage of amylose in wild-type and fl4 mature endosperm. The measurements were done on per milligram of dried endosperm. Values are the mean values with se (n = three individuals).