所有可转移元素家族都在最近的小麦基因组演变中发挥了作用,多重合体性对它们的活动没有影响
Nathan Papon1, Pauline Lasserre-Zuber1, Hélène Rimbert1
1INRAE, GDEC, Université Clermont Auvergne, Clermont-Ferrand, France.
The plant genome
|May 27, 2023
概括
小麦基因组显示了可转移元素 (TE) 的显著变异性,在不同的化水平上检测到新的插入. 聚化似乎没有增加TE转化率.
科学领域:
- 基因组学就是基因组学.
- 植物科学 植物科学
- 进化生物学 进化生物学
背景情况:
- 面包小麦 (Triticum aestivum L.) 拥有大型的六倍体基因组 (15 Gb),其中高比例 (85%) 的可移植元素 (TEs).
- 之前关于小麦遗传多样性的研究主要集中在基因上,使得TEs的基因组变异性,转移率和多性影响在很大程度上未被探索.
- 最近的进展为面包小麦及其双倍体和四倍体野生亲属提供了染色体规模的基因组组,使得全面的TE分析成为可能.
研究的目的:
- 量化转移元素 (TE) 分数内的基因组变异性,跨越不同小麦血统和 ploidy 水平.
- 调查聚化对小麦中TE动态和转化率的影响.
- 为了比较TE插入模式和跨二倍体,四倍体和六倍体小麦基因组的变异性.
主要方法:
- 计算了A,B和D亚基因组的基因对解决,基因定,全基因组对齐.
- 分析了13种Triticum aestivum品种 (六倍体),Triticum durum和Triticum dicoccoides (四倍体),Triticum urartu (二倍体AA) 和Aegilops tauschii (二倍体DD) 的组装基因组.
- 估计了TE分数的变异性,并确定了每个亚基因组的新型TE插入.
主要成果:
- TE分量的变化率在5%至34%之间,取决于物种的分歧.
- 在研究的物种中,每个亚基因组检测到400到13,000个新的TE插入.
- 观察到大多数TE家族在二倍体,四倍体和六倍体小麦中进行谱系特定的TE插入.
- 没有发现转换突发的证据或与多化相关的转换率的增加.
结论:
- 小麦TE的动态比以前认为的要复杂得多,这表明了进化的平衡模型,而不是持续的爆发.
- 在小麦中多化似乎不是增加TE活性的主要驱动因素.
- 这项研究提供了对小麦TEs的基因组变异性和演变的关键见解,这对于作物改进和理解基因组演变至关重要.
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