从进化角度看,基本RNA的核酸序列之间的信息渐变
Houssem Ben Khalfallah1,2, Mariem Jelassi2, Hajar Rissaoui1
1Laboratory AGEIS EA 7407, Team Tools for e-Gnosis Medical & Labcom CNRS/UGA/OrangeLabs Telecom4Health, Faculty of Medicine, University Grenoble Alpes (UGA), 38700 La Tronche, France.
International journal of molecular sciences
|July 27, 2024
概括
古代RNA结构可能在现代细胞中被保存. 研究人员发现原始RNA片段,称为体,在必需的细胞功能和老物种中更常见,这表明与早期生命进化的联系.
科学领域:
- 生命的起源研究研究生命的起源.
- 分子进化分子进化
- 基因组学就是基因组学.
背景情况:
- 从无生命的有机分子过渡到第一个原细胞,标志着生命历史的关键时刻.
- 假设最早的分子结构,包括RNA和,为现存的细胞生命奠定了基础.
- 这些原始分子的痕迹可能存在于当代生物的遗传物质中.
研究的目的:
- 为了调查祖先RNA结构在现代细胞RNA中留下可检测的印记的假设.
- 提出一个循环RNA模型作为潜在的祖先结构.
- 为了确定当前RNA中的遗留 pentameric 次序作为早期进化的标记.
主要方法:
- 分析现代RNA (核糖体和信使) 的核酸序列.
- 寻找特定的 pentameric (或更长) 片段,表明一个拟议的原始RNA结构.
- 在不同的细胞功能和物种中量化这些碎片的发生频率.
主要成果:
- 观察到已识别的五合体的发生频率的梯度.
- 在与重要细胞过程相关的RNA中,如蛋白质合成,核酸合成和细胞呼吸中,发现了高频率的五聚体.
- 这种频率梯度在物种中也很明显,与进化年龄相关,从古生物到真核生物.
结论:
- 这项研究提供了支持古代RNA结构在当今细胞RNA中留下分子痕迹的假设的证据.
- 鉴定到的 pentameric 次序及其发生梯度表明与基本细胞过程和物种进化的联系.
- 这些发现提供了关于生命进化的早期阶段以及从原细胞向生物体的过渡的见解.
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