涉及到异色素蛋白功能的基因的流行快速进化
bioRxiv : the preprint server for biology
|March 18, 2024
概括
调节异色染色素的基因迅速进化,比其他染色素调节者更容易发生变化. 这种由选择驱动的快速进化,可能是对可转移元素的反应,而不是它们的原因.
科学领域:
- 基因组学就是基因组学.
- 进化生物学 进化生物学
- 分子生物学分子生物学
背景情况:
- 基因贫乏和重复丰富的基因组区域 - - 异色素,对基因组稳定性和抑制可转移元素 (TEs) 至关重要.
- 尽管它具有重要的功能,但对调节异色素蛋白的基因的进化动态仍然不完全理解,有些基因显示出与保护期望相反的快速进化.
研究的目的:
- 综合调查涉及异种染色质功能的基因的进化模式,跨越多种不同的进化时间尺度.
- 为了确定快速进化是否是异性染色素相关基因的一般特征,还是孤立的现象.
主要方法:
- 编制了106个与异色素蛋白功能相关的候选基因的详尽列表.
- 分析了这些基因的进化变化,包括氨基酸替代和基因拷贝数变化.
- 与参与Polycomb-based repressive chromatin的基因进行了进化速率的比较,并评估了与基因组TE丰度的关联.
主要成果:
- 与Polycomb相关基因相比,调节异色素的基因表现出明显更高的进化变化率 (氨基酸替代,基因拷贝数).
- 这些蛋白质的结构域和内在无序区域 (IDR) 都受到积极选择,而IDR比例可以通过净化选择来维持.
- 异性染色质基因的进化速率与基因组TE丰度有负相关性,这表明存在动态相互作用.
结论:
- 异染色基因的快速演变是一种广泛的现象,可能是由异染色固有的功能及其与TEs的相互作用所驱动的.
- 快速的TE进化可能是异色染色体基因进化的结果,而不是原因.
- 这项研究提供了对异染色质相关基因进化的全球视角,突出了影响它们独特进化轨迹的因素.
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