促体捕获驱动了大肠杆菌中原基因的出现
bioRxiv : the preprint server for biology
|November 28, 2023
概括
新基因经常通过转录和翻译从非编码DNA中产生,这一过程被称为de novo基因诞生. 这项研究揭示了原基因在不断发展的细菌群体中迅速出现和稳定.
科学领域:
- 进化生物学 进化生物学
- 基因组学就是基因组学.
- 分子生物学分子生物学
背景情况:
- 新基因诞生,即从非基因序列中产生基因的出现,在真核生物中很常见,但在细菌中研究较少.
- 细菌拥有丰富的新型,谱系特异性基因,可以进行实验研究.
研究的目的:
- 在大肠杆菌长期进化实验 (LTEE) 中调查新基因诞生的早期阶段,称为原基因.
- 确定原基因在不断变化的细菌群体中出现和稳定的机制和时间.
主要方法:
- 来自大肠杆菌LTEE的遗传记录的分析.
- 识别表现出稳定的转录和/或翻译的非基因序列.
- 追踪致病突变及其固定时间.
主要成果:
- 在LTEE中,非基因区域经常经历转录,翻译和差异表达,作为新基因的原材料.
- 原基因通常来自插入元素或染色体转位,将调节序列融合到以前未表达的区域.
- 在未表达的序列上游的促进子形成也推动了原基因的出现.
- 大多数致病突变发生在LTEE早期 (在20,000代内) 并迅速被修复.
结论:
- 原基因在不断发展的细菌群体中频繁且稳定地出现.
- 这些原基因代表了形成新功能基因的潜在基质.
- LTEE为研究新基因诞生的动态提供了一个有价值的模型.
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