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Updated: Mar 7, 2026

Toeprinting Analysis of Translation Initiation Complex Formation on Mammalian mRNAs
Published on: May 10, 2018
Regulation Mechanisms of Viral IRES-Driven Translation
Kuo-Ming Lee1, Chi-Jene Chen1, Shin-Ru Shih2
1Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan.
Abstract:
Internal ribosome entry sites (IRESs) can be found in the mRNA of many viruses as well as in cellular genes involved in the stress response, cell cycle, and apoptosis. IRES-mediated translation can occur when dominant cap-dependent translation is inhibited, and viruses can take advantage of this to subvert host translation machinery. In this review, we focus on the four major types of IRES identified in RNA viruses, and outline their distinct structural properties and requirements of translational factors. We further discuss auxiliary host factors known as IRES trans-acting factors (ITAFs), which are involved in the modulation of optimal IRES activity. Currently known strategies employed by viruses to harness ITAFs and regulate IRES activity are also highlighted.
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