Internal initiation of translation of bovine viral diarrhea virus RNA

Initiation of translation on the bovine viral diarrhea virus (BVDV) interna l ribosomal entry site (IRES) was reconstituted in vitro from purified tran slation components to the stage of 48S ribosomal initiation complex formati on. Ribosomal binding and positioning on this mRNA to form a 48S complex di d not require the initiation factors eIF4A, eIF4B, or eIF4F, and translatio n of this mRNA was resistant to inhibition by a trans-dominant ef F4A mutan t that inhibited cap-mediated initiation of translation. The BVDV IRES cont ains elements that are bound independently by ribosomal 40S subunits and by eukaryotic initiation factor (eIF) 3, as well as determinants that mediate direct attachment of 43S ribosomal complexes to the initiation codon. (C) 1999 Academic Press.