Prokaryotes 中基因顺序的进化主要是由基因增加和损失驱动的
bioRxiv : the preprint server for biology
|June 26, 2025
概括
细菌和古生物的基因组进化是动态的. 基因的增加和损失主要导致合成的损失,基因组重组起到较小的作用. 这表明基因流动在塑造基因组顺序方面比转位更为重要.
科学领域:
- 基因组学就是基因组学.
- 微生物进化 微生物进化
- 生物信息学是一种生物信息学.
背景情况:
- 细菌和古生物的基因组通过基因增益 (水平基因转移) 和基因丧失,经历了显著的进化.
- 基因组重组,如逆转和转位,有助于基因顺序的变化,即使在密切相关的物种中也是如此.
- 保存的基因顺序在 prokaryotes 不是典型的,需要了解驱动这些变化的力量.
研究的目的:
- 量化基因组重组和基因流动 (获取和损失) 对细菌和古生物的基因顺序进化的相对贡献.
- 评估基因转位与基因增益/损失对合成基因块长度 (SBL) 的影响.
主要方法:
- 利用分析解决的"跳跃"模型,仅基于基因转位来预测合成基因块长度 (SBL) 的分布.
- 从跳跃模型中预测的SBL分布与实证观察到的SBL分布在各种细菌和古生物群体中进行了比较.
- 根据模型预测和经验数据的比较,计算了基因组重组事件与基因流动 (获取和损失) 的比率.
主要成果:
- "跳跃"模型准确地预测了SBL分布,为估计基因组重组与基因流量比率提供了基础.
- 在大多数研究的细菌和古生物群体中,基因组重组与基因流动的估计比率约为0.1.1.
- 这种较低的比率表明,基因增加和损失是 prokaryotic 基因组进化中 synteny 损失的主要驱动因素.
结论:
- 基因的增加和损失 (基因流动) 在塑造细菌和古生物中的基因顺序的进化轨迹方面比基因转位更有影响力.
- Prokaryotic 基因组的动态性质主要以基因内容的变化为特征,而不是通过转位进行广泛的基因顺序重组.
- 了解基因流动和重组之间的平衡对于理解微生物基因组进化和合成动态至关重要.
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