Dujiangyan Campus, Sichuan Agricultural University, Dujiangyan, Sichuan, China.
J Appl Genet. 2010;51(1):9-18. doi: 10.1007/BF03195705.
Extensive genetic variations of low-molecular-weight glutenin subunits (LMW-GS) and their coding genes were found in the wild diploid A- and D-genome donors of common wheat. In this study, we reported the isolation and characterization of 8 novel LMW-GS genes from Ae.longissima Schweinf. & Muschl., a species of the section Sitopsis of the genus Aegilops, which is closely related to the B genome of common wheat. Based on the N-terminal domain sequences, the 8 genes were divided into 3 groups. A consensus alignment of the extremely conserved domains with known gene groups and the subsequent cluster analysis showed that 2 out of the 3 groups of LMW-GS genes were closely related to those from the B genome, and the remaining was related to those from A and D genomes of wheat and Ae. tauschii. Using 3 sets of gene-group-specific primers, PCRs in diploid, tetraploid and hexaploid wheats and Ae. tauschii failed to obtain the expected products, indicating that the 3 groups of LMW-GS genes obtained in this study were new members of LMW-GS multi-gene families. These results suggested that the Sitopsis species of the genus Aegilops with novel gene variations could be used as valuable gene resources of LMW-GS. The 3 sets of group-specific primers could be utilized as molecular markers to investigate the introgression of novel alien LMW-GS genes from Ae. longissima into wheat.
野生二倍体 A 基因组和 D 基因组供体普通小麦具有丰富的低分子量麦谷蛋白亚基（LMW-GS）及其编码基因的遗传变异。本研究从节节麦属 Sitopsis 种 Ae. longissima Schweinf. & Muschl. 中分离和鉴定了 8 个新的 LMW-GS 基因。该种与普通小麦的 B 基因组密切相关。根据 N 末端结构域序列，8 个基因分为 3 组。与已知基因群的极度保守结构域的一致比对和随后的聚类分析表明，3 组 LMW-GS 基因中的 2 组与 B 基因组的基因密切相关，其余的与小麦和 Ae. tauschii 的 A 和 D 基因组的基因密切相关。使用 3 组基因群特异性引物，在二倍体、四倍体和六倍体小麦及 Ae. tauschii 中进行 PCR 未能获得预期产物，表明本研究获得的 3 组 LMW-GS 基因是 LMW-GS 多基因家族的新成员。这些结果表明，具有新基因变异的节节麦属 Sitopsis 种可以作为 LMW-GS 的有价值的基因资源。3 组基因群特异性引物可用作分子标记，以研究 Ae. longissima 中新的外源 LMW-GS 基因向小麦的渗入。
