核酶D处理一个小RNA调节器的多细胞发育在myxobacteria
Sarah M Cossey1, Gregory J Velicer1, Yuen-Tsu Nicco Yu1
1Institute for Integrative Biology, Department of Environmental Systems Science, ETH Zürich, 8092 Zurich, Switzerland.
Genes
|May 27, 2023
概括
核酶D (RNase D) 对于处理小RNA Pxr至关重要,该RNA控制了Myxococcus xanthus中的细菌发育. 破坏RNase D会阻止Pxr的成熟,停止发育并揭示其在sRNA处理中的作用.
科学领域:
- 细菌遗传学和分子生物学
- 微生物的发展和信号传递.
- 处理和调节RNA.
背景情况:
- 非编码小RNAs (sRNAs) 调节细菌中的基因表达.
- 在*Myxococcus xanthus*中,sRNA Pxr控制了从植物生长到多细胞发展的过渡.
- 在营养丰富的条件下,Pxr抑制了发育,在饥饿后抑制得到缓解.
研究的目的:
- 为了识别 sRNA Pxr 在 *Myxococcus xanthus* 发育中的功能必不可少的基因.
- 阐明Ribonuclease D (RNase D) 在Pxr成熟和功能中的作用.
- 了解Pxr处理的机制及其对细菌生命周期过渡的影响.
主要方法:
- 一种发育缺陷的 * Myxococcus xanthus * 菌株 (OC) 的转位子突变,以确定抑制突变.
- 在野生型和突变菌株中Pxr处理和积累的分析.
- 采用纯化的RNase D和Pxr转录的体外加工试验.
主要成果:
- 编码RNase D的*rnd*基因的破坏,取消了活性sRNA Pxr-S.S.的积累.
- RNase D的损失导致较长的Pxr前体转录 (Pxr-XL) 的积累增加,并减少了Pxr-S.
- 已证明RNase D在体外将Pxr-XL加工为Pxr-L,这表明Pxr成熟的两步处理途径.
结论:
- 家政核糖核酶RNase D在发育调节性sRNA Pxr.的成熟中发挥着中心作用.
- Pxr sRNA成熟涉及一个连续的两步处理路径,RNase D在最初的步骤中起作用.
- 这项研究提供了第一个涉及RNase D在sRNA处理中的证据,突出了它超越tRNA成熟的重要性.
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