title: Binding of ribosomes to 5'-terminal leader sequences of eukaryotic messenger RNAs.
abstract: Tobacco mosaic virus and turnip yellow mosaic virus genome RNAs, which have long (greater than or equal to 69 nucleotides) 5'-terminal leader sequences preceding the AUG initiation codon, can form disome initiation complexes when incubated with a wheat germ extract and sparsomycin. In tobacco mosaic virus RNA, whereas one ribosome in such complexes presumably occupies the AUG-containing initiation site, the other is located within the RNA leader sequence. The results favor a model of eukaryotic initiation in which ribosomes first bind to the 5' end of the mRNA independently of AUG, then advance to the AUG initiation codon, where protein synthesis ensues.
mesh_terms: D001483:Base Sequence; D003062:Codon / Q000378:metabolism; D008954:Models, Biological; D009029:Mosaic Viruses / Q000378:metabolism; D011132:Polyribosomes / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism*; D012367:RNA, Viral / Q000378:metabolism*; D012270:Ribosomes / Q000378:metabolism*; D014027:Tobacco Mosaic Virus / Q000378:metabolism; D014908:Triticum / Q000378:metabolism
chemical_list: D003062:Codon; D012333:RNA, Messenger; D012367:RNA, Viral