XUTs是酵母酵母中的Xrn1-敏感反感调节性非编码RNA的一类
E L van Dijk1, C L Chen, Y d'Aubenton-Carafa
1Centre de Génétique Moléculaire (CNRS UPR 3404), avenue de la Terrasse, 91198 Gif sur Yvette, France.
Nature
|June 24, 2011
概括
研究人员在酵母中发现了1658个新型不稳定转录 (XUT),其中大多数作为反感知调节器. 这些XUT对Xrn1外核酶敏感,揭示了一种新的基因调节层,涉及组质子修饰和适应性反应.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 酵母生物学的酵母生物学
背景情况:
- 非编码RNAs (ncRNAs) 对基因调节,染色质结构和基因组稳定性至关重要.
- 大型ncRNAs影响诸如癌症发育和X染色体失活等过程.
- 在Saccharomyces cerevisiae中的调节性ncRNAs的全基因组特征是有限的,特别是那些对Xrn1外核酶敏感的ncRNAs.
研究的目的:
- 在Saccharomyces cerevisiae中识别和描述新的调节性ncRNA.
- 研究Xrn1-敏感不稳定转录 (XUTs) 在基因调节中的作用.
- 为了阐明反意义XUTs,基因组修饰和基因沉默之间的关系.
主要方法:
- 链特异性RNA测序 (RNA-seq) 用于识别XUTs.
- 在含有的介质中分析适应性反应的XUT.
- RNA聚合酶II (RNAPII) 染色体免疫沉,然后在Xrn1-缺乏菌株中进行DNA测序 (ChIP-seq).
- 研究H3K4me3标记和Set1基因组甲基转移酶活性.
主要成果:
- 确定了1658个Xrn1-敏感的不稳定转录 (XUT),其中66%是打开阅读框架的反意义.
- XUTs是多基化和依赖于RNAPII的.
- 大多数XUT积聚在介质中,这表明它们在适应性反应中的作用.
- 反意义XUT导致目标基因的RNAPII占用率降低.
- H3K4me3标记与由反意义XUTs调节的基因相关,并对抗它们的压制性活动.
结论:
- 反感性ncRNA介导调节是Saccharomyces cerevisiae中广泛存在的途径.
- XUTs在基因表达控制和适应性反应中发挥着重要作用.
- 反意义XUT和H3K4me3甲基化之间的相互作用对于基因沉默至关重要.
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