流感C病毒的RNA依赖RNA聚合酶的晶体结构
Narin Hengrung1,2, Kamel El Omari2, Itziar Serna Martin1
1Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK.
Nature
|October 28, 2015
概括
我们确定了C型流感病毒RNA聚合酶的结构, 这一发现提升了对病毒RNA转录和复制机制的理解.
科学领域:
- 病毒学
- 结构生物学
- 分子生物学
背景情况:
- 负感RNA病毒利用RNA依赖RNA聚合酶进行转录和复制.
- 流感病毒聚合酶 (FluPol) 包含PB1,PB2和PA/P3子单元,具有特定的聚合酶活性,结和内核酶功能的域.
- 现有的结构显示流感A和B病毒聚合酶与促进器RNA结合,代表了启动前的状态.
研究的目的:
- 来确定C型流感病毒中的Apo-FluPol的结构.
- 阐明FluPol在预激活状态中的构造,与促进体结合状态不同.
- 在结构比较的基础上提出FluPol激活机制.
主要方法:
- 使用X射线结晶学来解决apo-FluPol的结构.
- 该结构以3.9 Å的分辨率确定.
- 在apo-FluPol结构和现有的促剂结合的FluPol结构之间进行了比较分析.
主要成果:
- 一种新的"封闭"形状的apo-FluPol被揭示出来,其中PB1处于中心,PB2封闭一个面,P3紧复合体.
- 这种闭合形状与促进体结合的FluPol结构有显著的差异.
- 盖结合部位被封闭,使得聚合酶与转录启动不相容,表明了预激活状态.
结论:
- 确定的结构捕获了封闭的,转录不活跃的apo-FluPol,可能代表新合成的聚合酶或非转录复合体中的聚合酶.
- 观察到的结构重组突显了流感病毒RNA聚合酶的结构灵活性.
- 这项研究提供了FluPol的激活机制以及病毒RNA转录和复制的调节.
相关概念视频
Leaky Scanning
5.9K
During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA. Marilyn Kozak discovered that the sequence RCCAUGG (where R...
5.9K
Nucleic Acid Structure
10.3K
The pentose sugar in DNA is deoxyribose, while in RNA the pentose sugar is ribose. The difference between the sugars is the presence of the hydroxyl group on the ribose's second carbon and a hydrogen on the deoxyribose's second carbon. The phosphate residue attaches to the hydroxyl group of the 5′ carbon of one sugar and the hydroxyl group of the 3′ carbon of the sugar of the next nucleotide, which forms a 5′ to 3′ phosphodiester linkage.
DNA Structure
DNA...
DNA Structure
DNA...
10.3K
Bacterial RNA Polymerase
33.6K
Unlike eukaryotes, bacteria use a single RNA Polymerase (RNAP) to transcribe all genes. The different subunits of bacterial RNAPhave distinct functions. The multisubunit structure of the bacterial RNAP helps the enzyme to maintain catalytic function, facilitate assembly, interact with DNA and RNA, and self-regulate its activity.
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
33.6K
Bacterial RNA Polymerase
13.5K
13.5K
Eukaryotic RNA Polymerases
27.9K
RNA Polymerase (RNAP) is conserved in all animals, with bacterial, archaeal, and eukaryotic RNAPs sharing significant sequence, structural, and functional similarities. Among the three eukaryotic RNAPs, RNA Polymerase II is most similar to bacterial RNAP in terms of both structural organization and folding topologies of the enzyme subunits. However, these similarities are not reflected in their mechanism of action.
All three eukaryotic RNAPs require specific transcription factors, of which the...
All three eukaryotic RNAPs require specific transcription factors, of which the...
27.9K
Eukaryotic RNA Polymerases
10.4K
10.4K


