Characterization of low-molecular-weight glutenin subunit genes and their protein products in common wheats.
To characterize the low-molecular-weight glutenin subunit (LMW-GS), we developed specific PCR primer sets to distinguish 12 groups of LMW-GS genes of Norin 61 and to decide their loci with nullisomic-tetrasomic lines of Chinese Spring. Three, two, and ten groups were assigned to Glu-A3, Glu-B3, and Glu-D3 loci, respectively. To identify the proteins containing the corresponding amino acid sequences, we determined the N-terminal amino acid sequence of 12 spots of LMW-GSs of Norin 61 separated by two-dimensional gel electrophoresis (2DE). The N-terminal sequences of the LMW-GS spots showed that 10 of 12 groups of LMW-GSs were expressed as protein products, which included LMW-i, LMW-m, and LMW-s types. Four spots were encoded by Glu-A3 (LMW-i). Three spots were encoded by Glu-B3 (LMW-m and LMW-s). Five spots were encoded by Glu-D3 (LMW-m and LMW-s). A minor spot of LMW-m seemed to be encoded by the same Glu-B3 gene as a major spot of LMW-s, but processed at a different site. Comparing among various cultivars, there were polymorphic and non-polymorphic LMW-GSs. Glu-A3 was highly polymorphic, i.e., the a, b, and c alleles showed one spot, the d allele showed four spots, and the e allele had no spot. Insignia used as one of the Glu-A3 null standard cultivars had a LMW-GS encoded by Glu-A3. We also found that Cheyenne had a new Glu-D3 allele. Classification of LMW-GS by a combination of PCR and 2DE will be useful to identify individual LMW-GSs and to study their contribution to flour quality.
Ikeda
T M
TM
Department of Crop Breeding, National Agricultural Research Center for Western Region, 6-12-1 Nishifukatsu, Fukuyama 721-8514, Japan. tmikeda@affrc.go.jp
Araki
E
E
Fujita
Y
Y
Yano
H
H
D000595:Amino Acid Sequence; D015180:Electrophoresis, Gel, Two-Dimensional; D005983:Glutens / Q000737:chemistry* / Q000235:genetics*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016133:Polymerase Chain Reaction; D014908:Triticum / Q000235:genetics* / Q000378:metabolism*
D005983:Glutens; C037302:glutenin