揭示 prokaryotes 中翻译启动的可塑性:超越不变的Shine-Dalgarno 序列
Karel Estrada1,2, Alejandro Garciarrubio3, Enrique Merino4
1Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos (UAEM), Cuernavaca, Morelos, México.
PloS one
|January 11, 2024
概括
Prokaryotic 翻译启动显示出超出 Shine-Dalgarno 序列的灵活性. 生物可以有效地启动翻译,即使在反Shine-Dalgarno序列核心的变异,挑战传统模型.
科学领域:
- 分子生物学分子生物学
- 基因组学就是基因组学.
- 进化生物学 进化生物学
背景情况:
- Prokaryotic 的翻译启动依赖于 16S rRNA 的 anti-Shine-Dalgarno (antiSD) 序列和 mRNA 的 Shine-Dalgarno (SD) 位点之间的相互作用.
- 抗SD序列的保存的5'-CCUCC-3'核心至关重要,但在侧面基中存在变异,很少在细菌和古生物中存在核心本身.
研究的目的:
- 分析抗SD序列的变异及其对 prokaryotes 的翻译启动的影响.
- 为了研究抗SD序列变异的遗传分布.
- 为了确定保存的抗SD核是否对于核糖体结合和翻译启动是绝对必要的.
主要方法:
- 对来自细菌和古生物的6400多个基因组序列进行了结合能预测分析.
- 生物被分为四个类别,基于保留的抗SD核心的存在和结合的证据.
主要成果:
- 确定了15个不同的抗SD变体组,通常与家族遗传起源相关.
- 在一些生物体中观察到核心抗SD序列内的变异.
- 生物被分为四组,包括那些有保存的核心显示结合,保存的核心缺乏结合,非保存的核心显示结合,以及那些缺乏两者.
结论:
- Prokaryotic 翻译启动表现出显著的序列灵活性,超出了正规的 Shine-Dalgarno 相互作用.
- 在所有 prokaryotes 中,保存的 antiSD 核心不是有效的翻译启动的绝对要求.
- 这些发现提供了关于 prokaryotic 生物体中翻译启动机制的进化适应性的见解.
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