Related Experiment Video
Updated: Aug 9, 2026
10:24
Xenopus laevis as a Model to Identify Translation Impairment
Published on: September 27, 2015
Complex formation between potyvirus VPg and translation eukaryotic initiation factor 4E correlates with virus
S Léonard1, D Plante, S Wittmann
1Centre de Microbiologie et Biotechnologie, INRS-Institut Armand-Frappier, Ville de Laval, Québec, Canada H7V 1B7.
Journal of Virology
|August 10, 2000
Summary
The viral protein VPg from turnip mosaic virus interacts with eukaryotic initiation factor eIF(iso)4E, crucial for translation. This interaction is essential for virus production, as demonstrated by symptom development in infected plants.
Area of Science:
- Plant Virology
- Molecular Biology
- Biochemistry
Background:
- The viral protein VPg of turnip mosaic potyvirus (TuMV) interacts with Arabidopsis thaliana eukaryotic initiation factor eIF(iso)4E.
- eIF(iso)4E is vital for mRNA cap binding and regulating translation initiation.
Purpose of the Study:
- To investigate the interaction between TuMV VPg and plant eIF4E isomers.
- To determine the biological significance of the VPg-eIF(iso)4E interaction in TuMV infection.
Main Methods:
- Protein interaction assays using VPg and eIF4E isomers from Arabidopsis thaliana and Triticum aestivum.
- Mapping of the VPg interaction domain and mutational analysis.
- In planta assays using Brassica perviridis infected with wild-type and mutant TuMV.
Main Results:
- VPg interacts with both eIF(iso)4E and eIF4E isomers from A. thaliana, and with wheat eIF(iso)4E.
- A 35-amino acid region on VPg was identified as the interaction domain, with a specific aspartic acid residue critical for binding.
- The cap analogue m(7)GTP inhibited VPg-eIF(iso)4E complex formation, indicating competition with cellular mRNAs.
- Plants infected with a mutant TuMV lacking the VPg-eIF(iso)4E interaction showed no viral symptoms.
Conclusions:
- The interaction between TuMV VPg and eIF(iso)4E is essential for viral replication and symptom development.
- VPg-eIF(iso)4E interaction represents a critical step in the potyvirus life cycle, potentially by hijacking the host translation machinery.
Related Concept Videos
00:56Viral Structure
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.
02:33Initiation of Translation
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...
02:28Leaky Scanning
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 stands for...
01:30Inhibitors of Viral Protein Synthesis
Protein synthesis is indispensable for viral replication, as viruses lack the cellular machinery required for this process and must hijack the host's translational apparatus. In response, host cells deploy a critical innate immune defense involving interferons, specialized cytokines that play a central role in inhibiting viral propagation.Upon viral detection, infected cells release interferons that bind to receptors on adjacent uninfected cells, activating the JAK-STAT signaling pathway and...
01:25Inhibitors Of Virion Release
Viral replication and dissemination rely on efficient mechanisms for host cell entry, genome replication, assembly, and release. Influenza viruses, such as types A and B, are negative-sense single-stranded RNA viruses with a segmented genome, that depend on two critical surface glycoproteins to carry out these processes: hemagglutinin (HA) and neuraminidase (NA). HA initiates infection by binding to sialic acid residues on the surface of host epithelial cells, facilitating receptor-mediated...
01:19Inhibitors of Virion Maturation and Assembly
As part of their replication cycle, certain viruses synthesize long precursor proteins called polyproteins within infected host cells. In human immunodeficiency virus (HIV), two major polyproteins are produced: Gag and Gag-Pol. The Gag polyprotein supplies the structural components of the virus, while Gag-Pol includes essential viral enzymes such as reverse transcriptase, integrase, and protease. After synthesis, these polyproteins move to the host cell membrane, where they assemble into an...