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Updated: Jun 23, 2025

Eukaryotic Polyribosome Profile Analysis

Published on: June 15, 2010

核糖体含量的单细胞异质性以及对生长规律的后果

Leandra Brettner¹, Kerry Geiler-Samerotte^1,2

¹Biodesign Institute Center for Mechanisms of Evolution, Arizona State University, Tempe, Arizona, USA.

bioRxiv : the preprint server for biology

|June 19, 2024

概括

细胞核糖体含量与人口增长率相关,但单细胞分析显示出显著的差异. 单个细胞不能严格调节核糖体水平以匹配生长,挑战现有的微生物生长规律理论.

科学领域:

微生物学微生物学
分子生物学分子生物学
系统生物学系统生物学

背景情况:

核糖体含量与人群生长率之间的相关性是微生物群体中一个成熟的"生长规律".
这一定律为最大生长的进化选择和细胞生长调节模型的理论提供了信息.
以前的研究仅限于人口层面的分析,使得单细胞层面的核糖体含量调节不清楚.

研究的目的:

通过检查核糖体含量和转录状态来研究微生物生长规律的单细胞基础.
为了确定单个细胞是否根据它们的环境和生长速度严格调节核糖体水平.
根据单细胞异质性,评估当前生长规律模型的适用性.

主要方法:

在两个不同的微生物物种上使用单细胞RNA测序技术: *Saccharomyces cerevisiae* (真核生物) 和 *Bacillus subtilis* (原核生物).
在各种条件下,分析了成千上万个单个细胞的核糖体和非核糖体转录基因变异.
利用计算模型来评估核糖体内容的分布及其与生长率的关系.

主要成果:

在两种物种中观察到单细胞核糖体含量的显著变化,独立于单个细胞生长速度.
确定了快速生长的细胞的子群体,具有缓慢生长或压力的转录特征,以及表现出压力标记的高核糖体含量细胞.
发现了具有独特转录状态的子群体,表明功能超出了最大增长率优化.

结论:

单细胞核糖体水平并没有精确调整以匹配人口增长率或营养素的可用性.
现有的高斯过程模型假设核糖体内容的正常分布是不足以解释观察到的异质性.
未来的生长调节和进化的模型必须纳入单细胞异质性,以准确地反映微生物生理学.

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