RNA helicase A is necessary for translation of selected messenger RNAs.

Center for Retrovirus Research and Department of Veterinary Biosciences, The Ohio State University, Columbus, Ohio 43210 USA.
Nature Structural & Molecular Biology (Impact Factor: 11.63). 07/2006; 13(6):509-16. DOI: 10.1038/nsmb1092
Source: PubMed

ABSTRACT RNA helicase A (RHA) is a highly conserved DEAD-box protein that activates transcription, modulates RNA splicing and binds the nuclear pore complex. The life cycle of typical mRNA involves RNA processing and translation after ribosome scanning of a relatively unstructured 5' untranslated region (UTR). The precursor RNAs of retroviruses and selected cellular genes harbor a complex 5' UTR and use a yet-to-be-identified host post-transcriptional effector to stimulate efficient translation. Here we show that RHA recognizes a structured 5'-terminal post-transcriptional control element (PCE) of a retrovirus and the JUND growth-control gene. RHA interacts with PCE RNA in the nucleus and cytoplasm, facilitates polyribosome association and is necessary for its efficient translation. Our results reveal a previously unidentified role for RHA in translation and implicate RHA as an integrative effector in the continuum of gene expression from transcription to translation.

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