涉及异色染色体功能的基因的普遍快速进化
Leila Lin1, Yuheng Huang1, Jennifer McIntyre1
1Department of Ecology and Evolutionary Biology, University of California, Irvine, CA, USA.
Molecular biology and evolution
|August 27, 2024
概括
调节异色染色素的基因迅速演变,与基于Polycomb的染色素中的基因不同. 这种由选择驱动的快速进化与异性染色有关.
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:
- 异染色素是一种基因贫乏和重复丰富的基因组区域,对基因组稳定性,染色体组织和抑制可转移元素至关重要.
- 尽管它很重要,但一些参与异性染色体调节的基因表现出快速进化,与高度保护的期望形成鲜明对比.
研究的目的:
- 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在Drosophila.
- 为了确定与其他染色质调节剂相比,快速进化是否是异染色质相关基因的一般特征.
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综合清单.
- 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压制色素的基因进行比较的进化速度.
主要成果:
- 调节异色素的基因表现出明显更频繁的进化变化 (氨基酸替代,基因拷贝数量变化),而不是那些涉及到基于Polycomb的抑制色素的基因.
- 这些蛋白质的结构域和内在无序区域都受到积极选择的影响,而净化选择可能会保留无序区域.
- 观察到这些基因的进化速率与可转移元素的基因组丰度之间存在负相关性.
结论:
- 异性染色素相关基因的快速演变是异性染色素独特功能的固有后果.
- 这项研究提出了一个模型,即快速转移的元素进化可能是异色染色体基因进化的结果,而不是原因.
- 提供了关于异染色体相关基因的进化及其独特进化轨迹的影响因素的广泛视角.
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