通过对248个基因组组合的策划,了解哺乳动物的TE多样性
Austin B Osmanski1, Nicole S Paulat1, Jenny Korstian1
1Department of Biological Sciences, Texas Tech University, Lubbock, TX, USA.
Science (New York, N.Y.)
|April 27, 2023
概括
哺乳动物具有相似的可转移元素 (TE) 多样性,但在最近的TE积累方面有所不同. 特定的TE类型,如长间隔的元素,影响基因组大小,饮食习惯可能与DNA转位子活性有关.
科学领域:
- 基因组学
- 进化生物学
- 生物信息学
背景情况:
- 可转移元素 (TE) 是可移动的基因序列,它们塑造了基因组的进化.
- 了解TE动态对于解读基因组大小变异和进化轨迹至关重要.
- 之前的研究提供了关于 TE 含量的见解,但对哺乳动物的大规模比较分析是有限的.
研究的目的:
- 进行迄今为止在胎盘哺乳动物基因组中最大的de novo可移植元素 (TE) 治愈.
- 研究最近的TE积累模式及其对哺乳动物物种基因组大小的影响.
- 探索 TE 含量,基因组大小和饮食等生态因素之间的潜在关联.
主要方法:
- 对248种胎盘哺乳动物进行基因组组分析.
- 可转移元素的新标识和注释.
- 对 TE 含量,多样性和最近的积累模式进行比较分析.
主要成果:
- 哺乳动物的总体 TE 含量和多样性保持不变,但最近的 TE 积累有显著的变化.
- 最近的TE扩张和静止事件在哺乳动物的基因组中被观察到.
- 长间隔元素 (LINE) 与基因组大小的增加有关,而DNA转位与较小的基因组相关.
- 哺乳动物基因组在任何给定的时间都倾向于由几种TE类型主导.
- 发现饮食习惯与DNA转子入侵的发生率之间存在相关性.
结论:
- 最近的TE动态,而不是整体的TE含量,是哺乳动物基因组大小变化的关键驱动因素.
- 特定的TE家族在基因组进化中起着不同的作用,影响基因组扩张或收缩.
- 这些发现为未来对胎盘哺乳动物进行比较性TE研究提供了有价值的基准,并表明生态因素可能会影响TE景观.
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