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Updated: Dec 25, 2025
09:05
MicroRNA-based Regulation of Picornavirus Tropism
Published on: February 6, 2017
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Translational Control of the Picornavirus Phenotype
1Chumakov Institute of Poliomyelitis and Virus Encephalites, Russian Academy of Medical Sciences, and, Moscow State University, Moscow, Russia.
Molecular Biology
|March 28, 2020
Summary
Picornaviruses use internal ribosome entry sites (IRES) for translation. IRES-acting factors (ITAFs) are crucial for this process, influencing viral properties and potentially cellular functions.
Area of Science:
- Virology
- Molecular Biology
- Genetics
Background:
- Picornaviruses are small RNA viruses relying on cap-independent translation.
- Internal ribosome entry sites (IRES) within the 5'-untranslated region (5'-UTR) are critical for this translation mechanism.
- Canonical translation initiation factors (eIFs) and IRES-acting factors (ITAFs) are essential for IRES function.
Purpose of the Study:
- To explore the role of ITAFs in picornavirus translation.
- To understand how ITAF interactions with viral cis-elements influence viral phenotypes.
- To investigate the broader implications of ITAFs in viral biology and cellular mRNA translation.
Main Methods:
- Analysis of viral cis-elements and their interaction with ITAFs.
- Investigation of ITAF functions in non-infected cells.
- Comparative studies of IRES-dependent translation mechanisms.
Main Results:
- Specific features of viral cis-elements significantly impact picornavirus phenotype, including tissue tropism and pathogenicity.
- Altered interactions between viral cis-elements and ITAFs are implicated in these phenotypic changes.
- ITAFs, as cellular RNA-binding proteins, possess diverse functions beyond viral translation.
Conclusions:
- ITAFs play a pivotal role in regulating picornavirus biological properties.
- The tissue distribution and properties of ITAFs can dictate the characteristics of viruses utilizing IRES-dependent translation.
- ITAFs are likely involved in regulating fundamental cellular processes through their role in translating cellular mRNAs.
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