Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, PR China.
Gene. 2013 Apr 25;519(1):55-9. doi: 10.1016/j.gene.2013.01.052. Epub 2013 Feb 9.
Three HMW-GS and the respective ORFs from diploid species Eremopyrum distans and Eremopyrum triticeum were characterized. Compared to homologous proteins, they showed novel modifications in all domains. In the N-terminals, the y subunit from Er. triticeum (Xey) had 98 aa residues. A short G/IIFWGTS peptide deletion was responsible for the reduced number of aa residues. The end peptide in the y subunit from Er. distans (Fy) was IPTLLR. This unique structure was involved in a replacement between x types with IPA/TLLK/R and y types with R/TSSQTVQ. Both y subunits share the same short peptide LAAQLPAMCRL as x types in the C-terminals. Phylogenic relationships among orthologous genes from Triticeae species revealed that Fy and Xey were neither purely x type nor purely y type based on the N and C terminal residues. Divergence times indicated that Glu-Xe1 and Glu-F1 were separated from each other and that Glu-Xe1 separated from orthologous loci of wild wheat relatives earlier than Glu-F1. Based on the divergence times among Glu-F1, Glu-Xe1, Glu-O1, Glu-St1, and Glu-Ta1, it is possible that genome F separation from O, St, and Ta in species of Henrardia persica, Pseudoroegneria stipifolia, and Taeniatherum crinitum was more recent than the separation of F and Xe.
从二倍体物种节节麦和赖草中鉴定出了三种高分子量谷蛋白（HMW-GS）及其相应的开放阅读框（ORF）。与同源蛋白相比，它们在所有结构域都表现出了新颖的修饰。在 N 端，来自赖草的 y 亚基（Xey）有 98 个氨基酸残基。一个短的 G/IIFWGTS 肽缺失导致氨基酸残基数量减少。来自节节麦的 y 亚基（Fy）的末端肽是 IPTLLR。这种独特的结构涉及到 x 型与 IPA/TLLK/R 和 y 型与 R/TSSQTVQ 之间的替换。y 亚基的 C 端与 x 型具有相同的短肽 LAAQLPAMCRL。来自禾本科物种的同源基因的系统发育关系表明，Fy 和 Xey 既不是纯粹的 x 型，也不是纯粹的 y 型，这取决于 N 和 C 末端的残基。分歧时间表明，Glu-Xe1 和 Glu-F1 彼此分离，并且 Glu-Xe1 从野生小麦近缘种的同源基因座分离的时间早于 Glu-F1。根据 Glu-F1、Glu-Xe1、Glu-O1、Glu-St1 和 Glu-Ta1 之间的分歧时间，Henrardia persica、Pseudoroegneria stipifolia 和 Taeniatherum crinitum 物种中 F 基因组与 O、St 和 Ta 的分离可能比 F 和 Xe 的分离更为近期。
