背景:白菊(Kar。etKir.)内夫斯基,这是一个常年,分布在俄罗斯和哈萨克斯坦的交叉授粉小麦草,被归类为爱丽曲贾,披碱草,和Lophyrum属由分类学家根据不同的分类学分类系统。然而,Lolioides的基因组组成仍然未知。为了确定E.lolioides的基因组组成和进化,我们使用了单拷贝核基因乙酰辅酶A羧化酶(Acc1)和延伸因子G(EF-G),多拷贝核基因内部转录空间(ITS),叶绿体基因trnL-F与荧光和基因组原位杂交。
结果:尽管ITS序列广泛同质化,鉴定出两个不同的谱系(伪黑属和大麦属)。Acc1和EF-G序列表明,除了伪黄病和大麦,未知基因组是Lolioides的第三个潜在供体。来自叶绿体DNA的数据表明,假骨是E.lolioides的母体供体。来自St基因组的特定FISH标记的数据表明Lolioides具有两组St基因组。基因组原位杂交(GISH)和荧光原位杂交(FISH)结果均证实了该物种中大麦基因组的存在。当E基因组被用作探针时,在42条染色体中没有发现信号。在Lolioides中检测到Acc1序列的E样拷贝,可能是由于来自E基因组物种的渗入。来自哈萨克斯坦的登录号W6-26586中的H染色体之一未与H基因组信号杂交,但在双色GISH的着丝粒区域上具有St基因组信号。
结论:系统发育和原位杂交表明,在Lolioides中存在两组假单胞菌和一组大麦基因组。E.lolioides的基因组配方设计为StStStStStHH。E.lolioides可能是通过四倍体披碱草(StH)和二倍体伪黄虫物种之间的杂交而起源的。E和未知基因组可能通过基因渗入参与E.lolioides的物种形成。根据基因组分类系统,应将E.lolioides转移到ElymusL.并更名为Elymuslolioidus(Kar。呃Kir.)混合。
BACKGROUND: Elytrigia lolioides (Kar. et Kir.) Nevski, which is a perennial, cross-pollinating wheatgrass that is distributed in Russia and Kazakhstan, is classified into Elytrigia, Elymus, and Lophopyrum genera by taxonomists on the basis of different taxonomic classification systems. However, the genomic constitution of E. lolioides is still unknown. To identify the genome constitution and evolution of E. lolioides, we used single-copy nuclear genes acetyl-CoA carboxylase (Acc1) and elongation factor G (EF-G), multi-copy nuclear gene internal transcribed space (ITS), chloroplast gene trnL-F together with fluorescence and genomic in situ hybridization.
RESULTS: Despite the widespread homogenization of ITS sequences, two distinct lineages (genera Pseudoroegneria and Hordeum) were identified. Acc1 and EF-G sequences suggested that in addition to Pseudoroegneria and Hordeum, unknown genome was the third potential donor of E. lolioides. Data from chloroplast DNA showed that Pseudoroegneria is the maternal donor of E. lolioides. Data from specific FISH marker for St genome indicated that E. lolioides has two sets of St genomes. Both genomic in situ hybridization (GISH) and fluorescence in situ hybridization (FISH) results confirmed the presence of Hordeum genome in this species. When E genome was used as the probe, no signal was found in 42 chromosomes. The E-like copy of Acc1 sequences was detected in E. lolioides possibly due to the introgression from E genome species. One of the H chromosomes in the accession W6-26586 from Kazakhstan did not hybridize H genome signals but had St genome signals on the pericentromeric regions in the two-color GISH.
CONCLUSIONS: Phylogenetic and in situ hybridization indicated the presence of two sets of Pseudoroegneria and one set of Hordeum genome in E. lolioides. The genome formula of E. lolioides was designed as StStStStHH. E. lolioides may have originated through the hybridization between tetraploid Elymus (StH) and diploid Pseudoroegneria species. E and unknown genomes may participate in the speciation of E. lolioides through introgression. According to the genome classification system, E. lolioides should be transferred into Elymus L. and renamed as Elymus lolioidus (Kar. er Kir.) Meld.