The arrows show the respective positions of the a and b subunits of glutelin (ca. 30 and 19 kDa, respectively), globulin (ca. 22 kDa), albumin (ca. 15 kDa), and prolamin (ca. 14 kDa) determined in SDS-PAGE experiments using the respective proteins, which were prepared according to the method of Ju et al. (2001).