Characterization of novel HMW-GS in two diploid species of Eremopyrum
Characterization of novel HMW-GS in two diploid species of Eremopyrum
复制标题
两个二倍体种 Eremopyrum 中新型 HMW-GS 的表征
作者：
Dai SF;Pu ZJ;Liu DC;Wei YM;Zheng YL;Hu XK;Yan ZH
对来自二倍体物种 Eremopyrum distans 和 Eremopyrum triticeum 的三种 HMW-GS 和各自的 ORF 进行了表征。与同源蛋白相比，它们在所有域中都显示出新颖的修饰。在 N 末端，y 亚基来自 Er。小麦 (Xey) 有 98 个氨基酸残基。短 G/IIFWGTS 肽缺失导致氨基酸残基数量减少。 Er y 亚基中的末端肽。距离 (Fy) 为 IPTLLR。这种独特的结构涉及 x 类型与 IPA/TLLK/R 和 y 类型与 R/TSSQTVQ 之间的替换。两个 y 亚基在 C 末端与 x 类型共享相同的短肽 LAAQLPAMCRL。小麦科物种的直系同源基因之间的系统发育关系表明，基于N和C末端残基，Fy和Xey既不是纯x型也不是纯y型。分歧时间表明Glu-Xe1和Glu-F1彼此分离，并且Glu-Xe1比Glu-F1更早地从野生小麦近缘种的直系同源基因座分离。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 crintum 物种中基因组 F 与 O、St 和 Ta 的分离可能比 F 和 Xe 的分离更晚。
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.