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pp.547-554
미성숙 종자로부터 추출된 전체 RNA를 이용하여 합성한 cDNA와 LMW-GS 특이 프라이머세트를 이용하여 43개의 LMW-GS 유전자를 분리하였다. 각각의 유추 아미노산은 상동성이 높은 20개의 시그널 펩타이드, N-말단 영역, 반복서열영역 그리고 C-말단 영역을 가지며 C-말단 영역에 분자내 혹은 분자간 이황화 결합을 형성하는 전형적인 8개의 시스테인을 가지고 있었다. 이들 시스테인의 위치는 첫번째, 일곱번째를 제외하고는 보존되어 있었다. Ikeda
Low-molecular-weight glutenin subunit (LMW-GS) in common wheat (Triticum aestivum L.) is important for quality processing of bread and noodles. The objectives of this study were to clarify the composition of LMW-GSs and to identify their corresponding proteins. Using LMW-GS specific primers we cloned and characterized 43 LMW-GS genes in the wheat cultivar ‘Jokyoung’. Some of these genes contain polypeptides different in size due to the presence of various deletions or insertions within repetitive and glutamine-rich domains. The comparison of deduced amino acid sequence of the LMW-GS genes in Jokyoung with that of 12 groups LMW-GSs of wheat cultivar Norin 61 showed that the deduced amino acid sequences were nearly the same to LMW-GS groups of 1, 2, 3/4, 5, 7, 10 and 11. All LMW-GS genes contain eight cysteine residues, which are conserved among all of the typical LMW-GS sequences. The relative positions of cysteine residues are also conserved, except those of the first and seventh. Based on phylogenetic analysis, the 43 sequences with the same N-terminal and C-terminal amino acid sequences were clustered in the same group. To identify the proteins containing the corresponding amino acid sequences, we determined the N-terminal amino acid sequence of 7 spots of LMW-GSs of Jokyoung separated by two-dimensional gel electrophoresis (2DE). Of them, Glu-B3 (LMW-m and LMW-s) and Glu-D3 (LMW-m) were detected in two and three spots, respectively and the others were not clear. Collectively, we classified diverse LMW-GSs and identified their corresponding protein products. These results will be helpful in breeding programs for improvement of wheat flour quality.
