源自Drosophila体细胞中的转子和mRNA的内源性siRNAs
Megha Ghildiyal1, Hervé Seitz, Michael D Horwich
1Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA.
概括
研究人员在Drosophila体细胞中发现了内源性小干扰RNA (siRNA). 这些siRNAs通过RNA干扰 (RNAi) 生成,向转子体和信使RNAs,表明它们在沉默遗传元素中的作用.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 在RNA生物学,RNA生物学.
背景情况:
- 小干扰RNAs (siRNAs) 在真核生物中调解RNA干扰 (RNAi).
- 在Drosophila melanogaster中,体细胞利用来自外源双链RNA (dsRNA) 的siRNA来进行抗病毒防御.
研究的目的:
- 在Drosophila melanogaster的体细胞中识别和表征内源性siRNA (内源-siRNA).
- 为了研究这些内源-siRNAs的起源和潜在功能.
主要方法:
- 从Drosophila体细胞中深度测序小RNA.
- 生物信息分析用于将小RNA映射到基因组特征,包括转子子和mRNA.
- 涉及Dicer-2和Argonaute2 (Ago2) 淘汰赛的遗传分析.
主要成果:
- 识别与转位子和异色序列对应的21核酸内源siRNAs.
- 检测补充信使RNA (mRNA) 的endo-siRNAs,特别是重叠区域.
- 证明Dicer-2和Ago2对于体内内-siRNAs的积累至关重要.
结论:
- 德罗斯菲拉体细胞从内源性转录生成内源siRNAs.
- 这些内源-siRNAs的功能可能是使转位子沉默,并可能通过mRNA向调节基因表达.
- 这些发现表明,在soma中存在一种基于RNAi的保护性防御机制,类似于Piwi交互RNAs的生殖线沉默.
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