A cis-acting element present within the Gag open reading frame negatively impacts on the activity of the HIV-1 IRES

Fernando Valiente-Echeverría; Maricarmen Vallejos; Anne Monette; Karla Pino; Alejandro Letelier; J Pablo Huidobro-Toro; Andrew J Mouland; Marcelo López-Lastra

doi:10.1371/journal.pone.0056962

A cis-acting element present within the Gag open reading frame negatively impacts on the activity of the HIV-1 IRES

PLoS One. 2013;8(2):e56962. doi: 10.1371/journal.pone.0056962. Epub 2013 Feb 25.

Authors

Fernando Valiente-Echeverría¹, Maricarmen Vallejos, Anne Monette, Karla Pino, Alejandro Letelier, J Pablo Huidobro-Toro, Andrew J Mouland, Marcelo López-Lastra

Affiliation

¹ Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Centro de Investigaciones Médicas, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.

Abstract

Translation initiation from the human immunodeficiency virus type-1 (HIV-1) mRNA can occur through a cap or an IRES dependent mechanism. Cap-dependent translation initiation of the HIV-1 mRNA can be inhibited by the instability element (INS)-1, a cis-acting regulatory element present within the gag open reading frame (ORF). In this study we evaluated the impact of the INS-1 on HIV-1 IRES-mediated translation initiation. Using heterologous bicistronic mRNAs, we show that the INS-1 negatively impact on HIV-1 IRES-driven translation in in vitro and in cell-based experiments. Additionally, our results show that the inhibitory effect of the INS-1 is not general to all IRESes since it does not hinder translation driven by the HCV IRES. The inhibition by the INS-1 was partially rescued in cells by the overexpression of the viral Rev protein or hnRNPA1.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Genes, gag / genetics*
HIV-1 / genetics*
HeLa Cells
Humans
Immunoblotting
Open Reading Frames / genetics*
Regulatory Sequences, Nucleic Acid / genetics
Reverse Transcriptase Polymerase Chain Reaction
rev Gene Products, Human Immunodeficiency Virus / genetics

Substances

rev Gene Products, Human Immunodeficiency Virus

Grants and funding

FV-E and MV conducted this work as part of their PhD Thesis and were supported by a CONICYT doctoral fellowship, AM was supported by a pre-doctoral CIHR studentship, and AL, who also participated in this study as part of his PhD Thesis, was supported by a VRAID, PUC fellowship and by a CONICYT beca de extensión. This study was supported by grants from the Fondo Nacional de Ciencia y Tecnología del Gobierno de Chile (FONDECYT) 1090318, Proyecto P09/016-F de la Iniciativa Científica Milenio del Ministerio de Economía, Fomento y Turismo to MLL, partial support from FONDECYT 1110672 and Proyecto Basal CARE 12/2007 to JPH-T, and the Canadian Institutes of Health Research (CIHR, MOP-56974) to AJM. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.