piRNA 3'-末端形成的遗传和机制多样性
Rippei Hayashi1, Jakob Schnabl1, Dominik Handler1
1Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA) Vienna Biocenter (VBC), Dr. Bohrgasse 3, 1030 Vienna, Austria.
Nature
|November 17, 2016
概括
在Drosophila中产生PIWI相互作用RNA (piRNA) 3'末端的两个途径,涉及黄瓜或茄子/Ago3核酶. 这一过程平衡了基因沉默路径,
科学领域:
- * 分子生物学
- *RNA生物学
- * 遗传学
背景情况:
- * 小调节RNA,包括微RNA,短干扰RNA和PIWI相互作用RNA (piRNA),对于基因沉默至关重要.
- * piRNAs指导PIWI-clade的阿尔戈诺特蛋白使动物性腺中的转子体沉默.
- * 虽然piRNA 5' 末端的形成已被了解,但piRNA 3' 末端的生物发生仍有较差的特征.
研究的目的:
- * 阐明Drosophila中与PIWI相互作用的RNA3'端形成的机制.
- * 确定参与生成成熟piRNA3'端的核酶.
- * 了解piRNA生物生成途径如何影响基因沉默.
主要方法:
- 在Drosophila中进行基因分析.
- * 生物化学测定以确定核酶和特征RNA处理.
- 使用测序对小RNA群体进行分析.
主要成果:
- * 通过两种不同的途径产生piRNA 3′末端:一种直接由Zucchini内核酶产生,另一种涉及PIWI-clade蛋白 Aubergine (Aub) 或Ago3,然后由exoribonuclease Nibbler进行切除.
- * 这些通路的相对贡献决定了piRNAs的局部化以及转录后和转录后基因沉默之间的平衡.
- *同时丢失Zucchini和Nibbler揭示了piRNA生物发生的最小阿尔戈诺依赖途径.
结论:
- * 提出了对piRNA生物发生的连贯模型,强调了Zucchini,Aub/Ago3和Nibbler在定义piRNA3'末端中的作用.
- * 这些发现为piRNAs对基因沉默的调节提供了机理性见解.
- 这项研究有助于进一步了解小RNA生物发生及其对基因组稳定性的影响.
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