Eucaryotic Initiation Factor 4b of Wheat Germ Binds to the Translation Initiation Region of Satellite Tobacco Necrosis Virus Ribonucleic Acid (Rna)

102 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1984.Highly purified eucaryotic initiation factor 4B from wheat germ binds the intact, monocistronic, uncapped mRNA, STNV RNA, in nitrocellulose filter mediated binding assays with a K(,d) = 1 x 10('-7)M. EIF4B also binds the 5'-terminal 52 nucleotides of STNV {5'- ('32)P}RNA (i.e., the translation initiation site of STNV RNA) with the same efficiency as intact STNV {5'- ('32)P}RNA, but does not bind control samples of randomly selected 5'- ('32)P 52 nucleotide long fragments. EIF4B also binds to 40 nucleotide long fragments, derived from STNV {C- ('125)I}RNA via 40s ribosome protection, as efficiently as it binds to STNV {5'- ('32)P}RNA. Thus, eIF4B binds to an apparently secondary structure free portion of STNV RNA that includes the translation initiation site of STNV RNA. Interestingly, wheat germ ribosomes show the same specificities toward the binding of fragments of STNV RNA. This suggests that eIF4B plays an essential role in the binding of mRNA to ribosomes. In support of this, eIF4B binds to two other eucaryotic mRNAs with similar efficiencies as STNV RNA.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD