saguaro 仙人掌病毒的结构 3'转化增强剂模仿 5' eIF4E 结合的 eIF4E 盖
Manju Ojha1, Jeff Vogt1, Naba Krishna Das1
1Department of Chemistry and Biochemistry, University of Maryland Baltimore County, Baltimore, MD 21250.
概括
植物病毒使用称为cap-independent转化增强剂 (CITEs) 的3'RNA结构来转化其基因组. 这项研究揭示了CITE如何模仿mRNA 5'盖来结合宿主蛋白质eIF4E.
科学领域:
- 分子生物学分子生物学
- 病毒学 病毒学
- 结构生物学 结构生物学
背景情况:
- 植物病毒利用3'盖独立的翻译增强剂 (CITEs) 来促进基因组翻译.
- 这些未封闭的RNA结构与像eIF4E这样的宿主转化因子结合的机制尚不清楚.
研究的目的:
- 通过3' CITE阐明5' cap-binding蛋白识别的结构基础.
- 了解病毒RNA如何模仿宿主mRNA的翻译.
主要方法:
- 使用Fab陪伴器测定萨瓜罗仙人掌病毒 (SCV) 3'CITE (PTE) 的晶体结构.
- 位点定向的突变发生 (G18A,G18C,G18U) 和结构分析.
- 生物物理结合试验 (凝电泳,ITC) 和与小麦和人类的分子对接 eIF4E.
主要成果:
- PTE RNA采用了带有伪结的三向结结构,为eIF4E结合提供瓜核酸G18.
- 晶体结构显示PTE支架预先组织为eIF4E相互作用,G18模仿mRNA 5' cap.
- 有约束力的研究证实PTE模仿mRNA 5'帽子用于eIF4E识别.
结论:
- 病毒性3'CITE利用RNA结构来模仿宿主mRNA的5'盖,从而实现盖独立的翻译.
- 这种仿真使病毒能够绕过正规的翻译机制,突出显示病毒适应策略.
- 了解这些机制,可以深入了解病毒与宿主之间的相互作用以及病原性RNA病毒的翻译.
更多相关视频
10:18Generation of Plasmid Vectors Expressing FLAG-tagged Proteins Under the Regulation of Human Elongation Factor-1α Promoter Using Gibson Assembly
Published on: February 9, 2015
37.1K
08:58In Vitro Transcribed RNA-based Luciferase Reporter Assay to Study Translation Regulation in Poxvirus-infected Cells
Published on: May 1, 2019
15.0K
相关概念视频
Leaky Scanning
5.1K
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...
5.1K
Initiation of Translation
33.0K
Initiating translation is complex because it involves multiple molecules. Initiator tRNA, ribosomal subunits, and eukaryotic initiation factors (eIFs) are all required to assemble on the initiation codon of mRNA. This process consists of several steps that are mediated by different eIFs.
First, the initiator tRNA must be selected from the pool of elongator tRNAs by eukaryotic initiation factor 2 (eIF2). The initiator tRNA (Met-tRNAi) has conserved sequence elements including modified bases at...
First, the initiator tRNA must be selected from the pool of elongator tRNAs by eukaryotic initiation factor 2 (eIF2). The initiator tRNA (Met-tRNAi) has conserved sequence elements including modified bases at...
33.0K
The Eukaryotic Promoter Region
16.3K
The eukaryotic promoter region is a segment of DNA located upstream of a gene. It contains an RNA polymerase binding site, a transcription start site, and several cis-regulatory sequences. The proximal promoter region is located in the vicinity of the gene and has cis-regulatory sequences and the core promoter. The core promoter is the binding site for RNA polymerase and is usually located between -35 and +35 nucleotides from the transcription start site. The distal promoter regions are...
16.3K
Eukaryotic Transcription Inhibitors
9.8K
Certain biochemical processes, such as embryonic development and cell growth regulation, depend on the repression of specific genes. DNA binding proteins known as eukaryotic transcription inhibitors regulate the repression of gene expression in eukaryotes. The presence of these inhibitors at the required location and time in the cell is triggered by the presence of hormones and additional signals from other cells.
Eukaryotic transcription inhibitors usually contain two distinct domains, a...
Eukaryotic transcription inhibitors usually contain two distinct domains, a...
9.8K
Viral Structure
62.3K
Viruses are extraordinarily diverse in shape and size, but they all have several structural features in common. All viruses have a core that contains a DNA- or RNA-based genome. The core is surrounded by a protective coat of proteins called the capsid. The capsid is composed of subunits called capsomeres. The capsid and genome-containing core are together known as the nucleocapsid.
62.3K
Eukaryotic Transcription Activators
11.1K
Transcription activators are proteins that promote the transcription of genes from DNA to RNA. In most cases, these proteins contain two separate domains ‒ a domain that binds to DNA and a domain for activating transcription; however, in some cases, a single domain is responsible for both binding and activation of transcription, as seen in the glucocorticoid receptor and MyoD.
The binding domains are capable of recognizing and interacting with regulatory sequences on the DNA. These...
The binding domains are capable of recognizing and interacting with regulatory sequences on the DNA. These...
11.1K
