2002 Volume 52 Issue 2 Pages 101-105
Protein composition of central region of white-core grains and non-white-core grains in the same rice cultivar for sake brewery was analyzed to detect the proteins specific to the white-core by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). We divided grains of two cultivars for sake brewery, Yamadanishiki and Gohyakumangoku into two groups, that is, grains with white-core and grains without white-core. We made a comparison between 2D-PAGE protein profiles of the central region of the white-core grains and that of non-white-core grains. The results showed that storage proteins, i.e., glutelin and prolamin, were contained in the white-core region as well as the central region of non-white-core grains. We found a protein spot in the 2D-PAGE profile specific to the white-core, which has an isoelectric point value of 4.5 and molecular weight size of 60 kDa. The protein spot was detected in the profiles of white-core region of two cultivars cultivated in 1998 and 2000, but not in those of non-white-core grains. The protein is considered to be associated with the expression of white-core in rice grains.
