The genera of the tribe Triticeae (family Poaceae), constituting many economically important plants with abundant genetic resources, carry genomes such as St, H, P, and Y. The genome symbol of Roegneria C. Koch (Triticeae) is StY. The St and Y genomes are crucial in Triticeae, and tetraploid StY species participate extensively in polyploid speciation. Characterization of St and Y nonhomologous chromosomes in StY-genome species could help understand variation in the chromosome structure and differentiation of StY-containing species. However, the high genetic affinity between St and Y genome and the deficiency of a complete set of StY nonhomologous probes limit the identification of St and Y genomes and variation of chromosome structures among Roegneria species. We aimed to identify St- and Y-enhanced repeat clusters and to study whether homoeologous chromosomes between St and Y genomes could be accurately identified due to high affinity. We employed comparative genome analyses to identify St- and Y-enhanced repeat clusters and generated a FISH-based karyotype of R. grandis (Keng), one of the taxonomically controversial StY species, for the first time. We explored 4 novel repeat clusters (StY_34, StY_107, StY_90, and StY_93), which could specifically identify individual St and Y nonhomologous chromosomes. The clusters StY_107 and StY_90 could identify St and Y addition/substitution chromosomes against common wheat genetic backgrounds. The chromosomes V_St, VII_St, I_Y, V_Y, and VII_Y displayed similar probe distribution patterns in the proximal region, indicating that the high affinity between St and Y genome might result from chromosome rearrangements or transposable element insertion among V_St/Y, VII_St/Y, and I_Y chromosomes during allopolyploidization. Our results can be used to employ FISH further to uncover the precise karyotype based on colinearity of Triticeae species by using the wheat karyotype as reference, to analyze diverse populations of the same species to understand the intraspecific structural changes, and to generate the karyotype of different StY-containing species to understand the interspecific chromosome variation.
Cytogenet Genome Res

中文翻译：

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基于新开发的 FISH 标记物表征 Roegneria grandis 的每个 St 和 Y 基因组染色体

小麦科（禾本科）属是许多具有丰富遗传资源的重要经济植物，携带有St、H、P、Y等基因组。Roegneria C. Koch（小麦科）的基因组符号为StY。St 和 Y 基因组在小麦科中至关重要，四倍体 StY 物种广泛参与多倍体物种形成。StY 基因组物种中 St 和 Y 非同源染色体的表征有助于了解含 StY 物种的染色体结构和分化的变异。然而，St和Y基因组之间的高遗传亲和力和一套完整的StY非同源探针的缺乏限制了Roegneria中St和Y基因组的鉴定和染色体结构的变异。物种。我们旨在鉴定 St 和 Y 增强的重复簇，并研究是否可以由于高亲和力而准确鉴定 St 和 Y 基因组之间的同源染色体。我们采用比较基因组分析来识别 St 和 Y 增强的重复簇，并生成了基于 FISH 的R. grandis核型(Keng)，这是分类学上有争议的 StY 物种之一，这是第一次。我们探索了 4 个新的重复簇（StY_34、StY_107、StY_90 和 StY_93），它们可以专门识别单个 St 和 Y 非同源染色体。簇 StY_107 和 StY_90 可以针对常见的小麦遗传背景识别 St 和 Y 添加/替代染色体。染色体 V_St、VII_St、I_Y、V_Y 和 VII_Y 在近端区域显示出相似的探针分布模式，表明 St 和 Y 基因组之间的高亲和力可能是由于染色体重排或 V_St/Y、VII_St/Y 之间的转座因子插入所致。和 I_Y 染色体在异源多倍化过程中。
细胞遗传基因组研究