序列偏差的出现和影响在进化上可形的哺乳动物串联阵列中
Margarita V Brovkina1, Margaret A Chapman2, Matthew L Holding3
1Graduate Program in Cellular and Molecular Biology, University of Michigan Medical School, Ann Arbor, MI, USA.
BMC biology
|August 23, 2023
概括
适应新环境的哺乳动物基因家族显示AT偏差增加,导致更大的非同义变异. 这种富含AT的含量影响了这些"外向"基因阵列中的基因调节和染色质组织.
科学领域:
- 基因组学就是基因组学.
- 进化生物学 进化生物学
- 哺乳动物遗传学 哺乳动物遗传学
背景情况:
- 恐龙灭绝后的哺乳动物辐射涉及快速多样化.
- 适应新领域推动了环境相互作用基因 (例如,化学传感器,免疫蛋白) 的创新.
- 这些"外向"的基因家族在人类中表现出高度的等位基因多样性和组织特异性表达.
研究的目的:
- 研究基因家族扩张,序列组成 (AT偏差) 和等位基因多样性之间的关系.
- 检查AT偏差异化和GC贫乏促进体在哺乳动物基因组进化中的作用.
- 了解塑造"外向"基因家族演变的力量.
主要方法:
- 人口遗传数据分析.
- 对比的基因组分析.
- 对基因家族扩张,序列含量和等位基因多样性的分析.
主要成果:
- "向外看的"基因的并列阵列位于AT偏差的同位素中,缺少CpG岛屿.
- 在基因家族的 cis 进化扩张过程中,AT 偏差可能会出现.
- 在AT偏差区域的人类基因显示低突变率,但为非同义变异和低重组率而丰富.
结论:
- 对非同义变异的耐受性和低重组率有助于"外向"基因阵列中的GC枯竭.
- 高AT含量影响这些基因家族的染色体组织和转录调节.
- 哺乳动物基因组进化模型需要纳入AT与GC偏差区域差异.
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