大豆子粒蛋白亚基变异种质的鉴定与筛选

Identification and Screening of Protein Subunit Variation Germplasm from Both Mutants and Natural Population in Soybean

本研究以大豆优良品种中品661的298份甲基磺酸乙酯(EMS)诱变株系和610份大豆品种(系)为试验材料,利用聚丙烯酰胺凝胶电泳(SDS-PAGE)技术,分离大豆种子蛋白并计算各蛋白亚基的相对含量及11S/7S值。研究结果表明,突变群体与自然群体中不同亚基的变异系数差异极显著,但均以β亚基变异范围最大。另外,突变群体的α、β和酸性蛋白亚基的变异范围均大于自然群体。相关性分析显示:11S球蛋白与7S球蛋白含量呈极显著负相关;11S/7S值与蛋白含量相关性不显著,11S/7S值与11S和7S球蛋白各组成亚基均呈显著相关。此外,本研究还筛选出亚基明显变异材料6份,其中Ax亚基突变体尚未见报道,11S/7S值大于3的材料10份,蛋白含量大于48%的材料7份。本研究鉴定和筛选的种子蛋白变异种质为大豆品质相关基因发掘和品种改良提供了材料基础。

In this study, soybean seed storage protein from 298 EMS mutant families derived from Zhongpin 661 and 610 varieties（lines）, was separated by polyacrylamide gel electrophoresis（SDS-PAGE）, repectively, and then the Quantity One（V4.62） software was used to quantify the relative content of protein subunits and the 11 S/7 S value. The results showed that significant difference for coefficient of variation（CV） of different subunits was observed between mutants and natural population, and the variation range of alpha, beta and acidic protein subunits in mutants was all larger than that in natural population, and notably the β subunit displayed the largest CV in both mutants and natural population. Furthermore, correlation analysis showed that the relative content of 11 S glycinin and 7 S β-conglycinin were negatively correlated, the 11 S/7 S value and each subunit of 11 S glycinin and 7 S β-conglycinin were significantly correlated as well, while the correlation was not significant for crude protein content and 11 S/7 S value. Also some elite germplasm was identified, among which, six displayed obvious variation in protein subunits, and a novel subunit mutant designated as Ax was also identified. Besides, ten showed higher 11 S/7 S value than 3, and seven exhibited higher protein content than 48%. These seed protein variants here we identified will provide important material basis for the related gene mining and genetic improvement of seed protein quality in soybean.