在单细胞藻 Chlamydomonas reinhardtii 中,miRNAs 控制基因表达
Attila Molnár1, Frank Schwach, David J Studholme
1Sainsbury Laboratory, John Innes Centre, Norwich NR4 7UH, UK.
Nature
|June 1, 2007
概括
这项研究揭示了Chlamydomonas reinhardtii.这种藻类中微RNA (miRNA) 和小干扰RNA (siRNA) 的存在. 这些发现表明,复杂的RNA沉默在原始真核细胞的多细胞性之前已经演化.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 进化生物学 进化生物学
背景情况:
- 微RNA (miRNA) 和小干扰RNA (siRNA) 是真核生物中基因表达的关键调节者.
- 这些RNA分子由Dicer核酶处理,并在含有阿尔戈纳特的复合体中起作用.
- 以前,人们认为miRNAs是随着多细胞性进化而形成的,而单细胞生物中没有这种特征.
研究的目的:
- 为了研究单细胞藻类Chlamydomonas reinhardtii中小RNA的存在和功能.
- 为了探索miRNA和siRNA路径的进化起源.
- 为了确定RNA沉默系统是否存在于多细胞化之前.
主要方法:
- 生物信息学分析了来自Chlamydomonas reinhardtii的小RNA序列.
- 识别和表征miRNA和siRNA前体和成熟分子.
- 与已知的植物和动物RNA沉默通路进行比较分析.
主要成果:
- 在Chlamydomonas reinhardtii中发现了miRNA和假定的miRNA前体.
- 识别与高层植物中发现的物种相似的siRNA物种.
- 克拉米多马纳斯 (Chlamydomonas reinhardtii) 具有功能性的RNA沉默机制.
结论:
- 在单细胞藻中存在miRNA和siRNA的存在挑战了miRNAs仅与多细胞性进化在一起的概念.
- 复杂的RNA沉默系统,包括miRNA通路,可能起源于植物和动物血统分歧之前的早期真核细胞.
- 这项研究提供了RNA介导基因调节的古代进化起源的证据.
相关概念视频
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