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在功能缓冲有害突变模型下的进化可以导致蛋白质编码基因的积极选择
Runxi Shen1, Miwa Wenzel2, Philipp W Messer1
1Department of Computational Biology, Cornell University, Ithaca, NY, United States.
Evolution; international journal of organic evolution
|July 19, 2023
概括
选择性压力可以驱动氨基酸变化,但缓冲机制,与军备竞赛不同,导致较少可检测的适应性固定. 这是一个很棒的节目,这是一个很棒的节目.
科学领域:
- 进化生物学是进化的生物学.
- 人口遗传学 人口遗传学
- 分子进化是分子进化的过程.
背景情况:
- 对DNA序列的选择性压力可以偏离中性进化,可以通过麦当劳-克莱特曼 (MK) 测试来检测.
- 由自然选择驱动的氨基酸替代通常与遗传军备竞赛或进化的蛋白质功能有关.
- 一个缓冲机制,可能受到Wolbachia内共生体的影响,可能会驱动选择性氨基酸固定,正如在Drosophila melanogaster中对袋子玉子 (bam) 和Sex lethal (Sxl) 的研究表明的那样.
研究的目的:
- 在选择性氨基酸固定的缓冲机制下评估种群遗传模式.
- 将沃尔巴基亚缓冲模型的进化动态与军备竞赛/功能变化模型进行比较.
- 评估这些模型对MK测试的统计能力的影响.
主要方法:
- 使用模拟来建模沃尔巴基亚缓冲机制的进化动态.
- 在缓冲和军备竞赛模型下分析了人口遗传模式.
- 评估了MK测试的统计能力,以检测偏离中性进化.
主要成果:
- 缓冲模型预测了选择性氨基酸替代,但与军备竞赛模型相比,适应性固定的比例较低.
- 在缓冲模型下,MK测试显示出明显较低的统计能力来检测缓冲模型下的中性演变偏差.
- 在Drosophila melanogaster的bam基因中观察到的选择模式与军备竞赛模型比缓冲模型更一致.
结论:
- 缓冲机制导致较少可检测的适应性氨基酸替代比军备竞赛模型.
- 在缓冲场景下,MK测试检测选择的功率降低.
- 对于D. melanogaster中bam基因的实证数据支持对拟议的缓冲机制的军备竞赛模型.
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