Cereal Chem 63:420-427   |  VIEW ARTICLE
Genetic Variation of Storage Proteins in Sorghum Grain: Studies by Isoelectric Focusing and High-Performance Liquid Chromatography.

L. V. S. Sastry, J. W. Paulis, J. A. Bietz, and J. S. Wall. Copyright 1986 by the American Association of Cereal Chemists, Inc. 

The genetic variability of the storage proteins in grain of several inbreds and hybrids of sorghum (Sorghum bicolor (L. ) Moench) and varieties representing different races was investigated by separating extracted proteins by isoelectric focusing (IEF) and reversed-phase high-performance liquid chromatography (RP- HPLC). The kafirins were extracted from the ground grain with 60% tert-butanol and the reduced alcohol- soluble glutelins (ASGs) were extracted with 60% tert-butanol containing 5% 2-mercaptoethanol. IEF was conducted with reduced-alkylated proteins in thin polyacrylamide gels containing 2% pH 6-8 ampholines and 8M urea, and the resolved proteins were visualized with silver stain. RP-HPLC was performed on a large pore column by gradient elution with increasing concentration of acetonitrile in water. Both separations indicated that kafirins and ASGs from the same genotype contain mostly the same proteins but with quantitive differences in amounts. Grains of different inbreds usually contained some different kafirin and ASG proteins; the hybrids contained proteins inherited from both parents, with those from the female predominating. Representatives of the different sorghum races varied in their component alcohol-soluble proteins, with those most widely removed from the geographical center of origin showing the greatest differences.