丁核酸偏好是Drosophila melanogaster血统中明显的编码子偏好逆转的基础
Haruka Yamashita1,2, Tomotaka Matsumoto1,2, Kent Kawashima1
1Laboratory of Evolutionary Genetics, Department of Genomics and Evolutionary Biology, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan.
概括
种群遗传分析显示,Drosophila中子使用偏差受主要子偏好 (MCP) 和二核酸偏好的影响. 这些力量相互作用,导致复杂的固定偏差模式和明显的反转在代偏好.
科学领域:
- 人口遗传学 人口遗传学
- 分子进化分子进化
- 德洛索菲拉基因组学
背景情况:
- 同义代码的使用偏差是推断种群遗传学的关键因素.
- 主要编码子偏好 (MCP) 为翻译上优越的编码子带来了健康益处.
- 以前的研究集中在Drosophila simulans血统上.
研究的目的:
- 研究Drosophila物种中对同义位点和内突作用的相互作用力.
- 分析子家族和基因系特定的固定偏差模式.
- 为了探索在Drosophila melanogaster.中发生的编码子偏好逆转的证据.
主要方法:
- 精细规模的人口遗传分析.
- 对自然发生的多形态的Codon家族和谱系特定分析.
- 编码和内子序列中的固定偏差的比较.
- 对X链接和自体位点的等位基频率和固定率的分析.
主要成果:
- 观察到对GC终端子的固定偏差,在Drosophila simulans血统中的同名家族中方向一致但大小异质.
- 在Drosophila melanogaster血统中检测到意想不到的编码器偏好逆转,特别是在NAY编码器家族中.
- 丁核酸偏好 (ApT比ApC) 反对在编码和内核区域的GC偏好力量.
- 证据表明,转化选择和二核酸偏好的相对有效性的变化是明显的子偏好逆转的基础.
结论:
- 主要密码子偏好和二核酸偏好之间的相互作用形成了Drosophila的同义位点进化.
- 在Drosophila melanogaster中明显的编码体偏好逆转与特定的编码体家族和tRNA修饰有关.
- 转化选择和二核酸偏好的相对强度可以导致同名地点的复杂进化动态.
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