title: Mapping of the large RNA genome segment of infectious pancreatic necrosis virus by hybrid arrested translation.
abstract: Segment A, the larger dsRNA segment of IPNV which encodes three of the four virus-coded polypeptides (preVP2, VP3, and NS) was cloned and physically mapped. The plus and minus RNA strands of the virus genome were separated and the A+ and B+ RNA strands were identified. A nested set of cDNA subclones, coterminal with the 5' end of A+ RNA, were used in hybrid arrested translation experiments. Hybrid arrest conditions which blocked the 5' two-thirds of A+ RNA allowed the in vitro synthesis of only VP3, while hybridization of the RNA to cDNA representing the 5' half of A+ RNA allowed the synthesis of both NS and VP3 but not of preVP2. In vitro translation of A+ RNA yielded all three polypeptides. It is, therefore, concluded that the order of the three polypeptides on A+ RNA is 5'-preVP2-NS-VP3-3'. These results imply that internal initiation of translation could take place on the RNA at least in vitro at sites located hundreds of nucleotides downstream from the first in-phase AUG codon near the 5' end.
mesh_terms: D000818:Animals; D003001:Cloning, Molecular; D004247:DNA; D005399:Fishes / Q000382:microbiology; D005814:Genes, Viral; D009693:Nucleic Acid Hybridization; D014176:Protein Biosynthesis; D012330:RNA, Double-Stranded / Q000235:genetics; D012367:RNA, Viral / Q000235:genetics*; D012087:Reoviridae / Q000235:genetics*; D017361:Viral Nonstructural Proteins; D014764:Viral Proteins / Q000235:genetics*; D015678:Viral Structural Proteins
chemical_list: D012330:RNA, Double-Stranded; D012367:RNA, Viral; D017361:Viral Nonstructural Proteins; D014764:Viral Proteins; D015678:Viral Structural Proteins; D004247:DNA