1. Human ribosomal protein L18a interacts with hepatitis C virus internal ribosome entry site
- Author
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P. Srinivasan, Saumitra Das, Renuka Pudi, Karthik Bodhinathan, Koyeli Mapa, and Debojyoti Dhar
- Subjects
Ribosomal Proteins ,DNA, Complementary ,5.8S ribosomal RNA ,Molecular Sequence Data ,Hepacivirus ,Biology ,In Vitro Techniques ,Ribosome assembly ,Hepatitis C virus internal ribosome entry site ,chemistry.chemical_compound ,Virology ,Eukaryotic initiation factor ,Sequence Homology, Nucleic Acid ,Initiation factor ,Humans ,Eukaryotic Small Ribosomal Subunit ,Gene Library ,Microbiology & Cell Biology ,Binding Sites ,Base Sequence ,fungi ,General Medicine ,Molecular biology ,Recombinant Proteins ,Internal ribosome entry site ,chemistry ,Nucleic Acid Conformation ,RNA, Viral ,Eukaryotic Ribosome ,5' Untranslated Regions ,Ribosomes ,HeLa Cells ,Protein Binding - Abstract
Translation initiation of hepatitis C virus RNA occurs via ribosome binding to an ‘internal ribosome entry site (IRES)’ located in the 5′untranslated region of the viral RNA. The principle interaction between the 40S ribosomal subunit and the HCV IRES has been shown to be largely factor independent, which is followed by the joining of the 60S ribosomal subunit to form functional 80S complex. However several additional cellular proteins have been reported to bind to HCV IRES and enhance the initiation of translation. In order to identify novel factors involved in the ribosome assembly during internal initiation of HCV RNA, northwestern screening of a HeLa cDNA expression library was performed, using HCV IRES RNA as probe. We demonstrate here, that human ribosomal protein L18a, a constituent of 60S subunit, interacts with HCV IRES RNA. This interaction was further confirmed by using a recombinant protein similar to L18a (sL18a), cloned from human blood. Interestingly, addition of increasing concentration of the purified recombinant sL18a protein, showed moderate stimulation of HCV IRES activity in the in vitro translation assay. These observations suggest that the human L18a might influence the HCV IRES mediated translation.
- Published
- 2005