Related Experiment Video
Updated: Sep 29, 2025
08:58
In Vitro Transcribed RNA-based Luciferase Reporter Assay to Study Translation Regulation in Poxvirus-infected Cells
Published on: May 1, 2019
15.2K
Picornavirus translation strategies.
Rosario Francisco-Velilla1, Azman Embarc-Buh1, Salvador Abellan1
1Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Madrid, Spain.
FEBS Open Bio
|March 21, 2022
Summary
Picornaviruses use a unique RNA structure called an internal ribosome entry site (IRES) to hijack cellular machinery for viral protein synthesis. This review details the modular structure of IRES elements and their interactions with cellular factors for viral replication.
Area of Science:
- Virology
- Molecular Biology
- Genetics
Background:
- Picornaviruses possess limited coding capacity, necessitating reliance on host cell machinery for replication.
- Viral RNA competes with host mRNAs for cellular protein synthesis resources upon cell entry.
Purpose of the Study:
- To review specialized strategies employed by picornaviruses for efficient viral gene expression.
- To summarize recent findings on the structure and function of picornavirus internal ribosome entry site (IRES) elements.
Main Methods:
- Review of existing literature on picornavirus replication and gene expression.
- Analysis of structural and functional studies on IRES elements.
Main Results:
- Picornavirus genomes feature a highly structured 5´ untranslated region (UTR) containing an IRES element.
- IRES elements are crucial for directing viral protein synthesis and initiating viral replication.
- Recent studies reveal a modular structure of IRES elements, facilitating interactions with ribosomes, eIFs, and RNA-binding proteins.
Conclusions:
- Picornavirus IRES elements represent a sophisticated adaptation for overcoming host translational control.
- Understanding IRES structure and interactions is key to deciphering viral replication mechanisms.
Related Concept Videos
02:28Leaky Scanning
5.3K
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...
5.3K
02:33Initiation of Translation
35.1K
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...
35.1K
01:29Viruses with RNA Genomes
180
RNA viruses are categorized into positive-strand, negative-strand, or double-stranded groups based on their genomic structure and replication mechanisms. This classification dictates how they exploit host cellular machinery for protein synthesis and replication. Some RNA viruses also utilize reverse transcription as part of their life cycle, further diversifying their replication strategies.Positive-Strand RNA VirusesPositive-strand RNA viruses have genomes that function directly as messenger...
180
01:29Translation in Prokaryotes
308
Prokaryote translation is a complex, highly coordinated process that converts genetic information from mRNA into functional proteins. It involves three stages: initiation, elongation, and termination, each facilitated by specific molecular components.Initiation of TranslationThe process begins with the assembly of the ribosomal subunits and initiation factors on the mRNA. In bacteria, the 30S ribosomal subunit recognizes the Shine-Dalgarno sequence in the mRNA, a conserved region upstream of...
308
01:20Cotranslational Protein Translocation
7.8K
Translocation of proteins across membranes is an ancient process that occurs even in bacteria and archaebacteria. In fact, the components of the translocation machinery are still conserved between prokaryotes and eukaryotes.
Sec61 channel partners for cotranslational translocation
During cotranslational translocation, the Sec61 channel partners with the signal recognition particle (SRP), the signal recognition particle receptor (SR), and the ribosomes to transport the nascent polypeptide chain...
Sec61 channel partners for cotranslational translocation
During cotranslational translocation, the Sec61 channel partners with the signal recognition particle (SRP), the signal recognition particle receptor (SR), and the ribosomes to transport the nascent polypeptide chain...
7.8K
01:29Subviral Agents
154
Subviral agents are infectious entities that resemble viruses but lack one or more viral components, such as a capsid or essential replication machinery. These agents include viroids, prions, and satellites, each possessing distinct structural and functional characteristics that influence their mode of infection and replication.Viroids are the simplest subviral agents, consisting of circular, single-stranded RNA molecules without a protein coat. They exclusively infect plants, relying entirely...
154