Translation initiation at alternate in-frame AUG codons in the rabies virus phosphoprotein mRNA is mediated by a ribosomal leaky scanning mechanism.
The phosphoprotein of rabies virus is a 297-amino-acid polypeptide encoded by the longest open reading frame of the P gene. Immunoprecipitation experiments using a monoclonal antiserum directed against the P protein detected the P protein and at least four additional shorter products in infected cells, cells transfected with a plasmid encoding the wild-type P protein, and purified virus (CVS strain). By means of deletion analyses, these proteins were shown to be translated from secondary downstream in-frame AUG initiation codons. Immunofluorescence experiments indicated that all these P products were found in the cytoplasm of transfected cells; however, the proteins initiated from the third, fourth, and fifth AUG codons were found mostly in the nucleus. Changes in the 5'-terminal region of the P mRNA (including site-specific mutations, deletions, and insertions) demonstrated that a leaky scanning mechanism is responsible for translation initiation of the P gene at several sites.
Chenik
M
M
Laboratoire de Génétique des Virus, Centre National de la Recherche Scientifique, Gif-sur-Yvette, France.
Chebli
K
K
Blondel
D
D
D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D003062:Codon; D006224:Cricetinae; D008969:Molecular Sequence Data; D010750:Phosphoproteins / Q000235:genetics*; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000378:metabolism*; D011820:Rabies virus / Q000235:genetics*; D012270:Ribosomes / Q000378:metabolism*; D014162:Transfection; D014764:Viral Proteins / Q000235:genetics*
D003062:Codon; D010750:Phosphoproteins; D012333:RNA, Messenger; D014764:Viral Proteins