人类中TBC1D3基因家族的独立扩展,选择和超变性
Xavi Guitart1, David Porubsky1, DongAhn Yoo1
1Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA.
bioRxiv : the preprint server for biology
|April 24, 2024
概括
灵长类动物特异的TBC1D3基因家族在人类中扩大,影响了额叶皮层的发育. 尽管拷贝数量和结构具有很高的变异性,但人类TBC1D3的表达受到限制,这可能解释了人口差异.
科学领域:
- 基因组学就是基因组学.
- 进化生物学 进化生物学
- 神经科学是一个神经科学.
背景情况:
- TBC1D3基因家族是灵长类的特异性基因,对神经元祖先的增殖和前皮层扩张至关重要.
- 由于它位于复杂的,高度相似的细分重复中,调查TBC1D3一直很困难.
研究的目的:
- 在灵长类物种中测序和组装TBC1D3基因家族.
- 了解人类和非人类灵长类动物中TBC1D3的进化动态,拷贝数变异和表达模式.
主要方法:
- 利用了34个人类和11种非人类灵长类动物的长读测序数据.
- 分析了基因重复事件,拷贝数变异,结构异构性,以及积极选择的证据.
- 研究了TBC1D3基因表达模式.
主要成果:
- TBC1D3在至少五种灵长类血统中独立复制,通常靠近染色体17号染色体上的染色体重排.
- 人类TBC1D3单元型表现出极端的副本数变化 (多达20个副本) 和结构异构性 (90%).
- 观察到积极选择的证据和预测的人类TBC1D3蛋白序列的显著变化. 人类的表达仅限于特定的副本,主要是在TBC1D3-CDKL对应组内.
结论:
- TBC1D3基因家族的复杂进化史,包括多重重复和高变性,是由选择塑造的.
- 尽管基因家族扩张,但TBC1D3在人类中的有限表达可能解释了它在人类人口中的变异性以及它在皮层发育中的作用.
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