在模型原细胞中对遗传聚合物的模板导向合成
Sheref S Mansy1, Jason P Schrum, Mathangi Krishnamurthy
1Howard Hughes Medical Institute, Department of Molecular Biology and the Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
Nature
|June 6, 2008
概括
具有脂肪酸膜的原始原细胞可以吸收营养,与现代细胞不同. 这表明早期生命可能是异质的,在没有复杂的运输系统的情况下利用环境资源.
科学领域:
- 生命起源研究研究生命的起源.
- 早期膜的生物物理学
- 原细胞研究研究.
背景情况:
- 现代细胞膜是极性/充电分子的障碍物,需要蛋白质载体.
- 这种屏障功能使得了解早期生命和异质性潜力变得复杂.
- 脂膜缺乏生长和分裂的动态特性.
研究的目的:
- 为了研究 prebiotically可信的膜的营养吸收的透性.
- 确定早期的原细胞是否可能在没有运输机械的情况下是异质的.
主要方法:
- 利用基于脂肪酸的囊泡作为原细胞膜的模型.
- 研究了带电分子,特别是核酸的穿越这些膜的过程.
- 评估了封装内容进行模板复制的能力.
主要成果:
- 脂肪酸膜对核酸等带电分子具有透性.
- 激活的核酸自发地穿过膜进入原细胞内部.
- 在原细胞内发生了有效的模板复制,这表明功能吸收.
结论:
- 益生菌可信的膜可以在没有复杂的运输系统的情况下促进营养的获取.
- 早期的原细胞可能是有义务的异质细胞,依赖于环境吸收.
- 脂肪酸膜为早期细胞生命和新陈代谢提供了一个可行的模型.
相关概念视频
01:32PCR
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Conversion of...
02:05DNA as a Genetic Template
Two structural features of the DNA molecule provide a basis for the mechanisms of heredity: the four nucleotide bases and its double-stranded nature. The Watson-Crick model of double-helical DNA structure, proposed in 1952, drew heavily upon the X-ray crystallography work of researchers Rosalind Franklin and Maurice Wilkins. Watson, Crick, and Wilkins jointly received the Nobel Prize in Physiology or Medicine for their work in 1962. Franklin was, controversially, excluded from the prize for...
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