Spliced and prematurely polyadenylated Jaagsiekte sheep retrovirus-specific RNAs from infected or transfected cells.

Jaagsiekte sheep retrovirus (JSRV) is the etiologic agent of a contagious lung cancer of sheep, ovine pulmonary adenocarcinoma (OPA). In this study, we characterized the virus-specific RNAs in 293T cells transiently transfected with a human cytomegalovirus promoter-driven JSRV expression plasmid, in productively infected OHH1.LU deer lung cells, and in OPA tumors from field isolates. Typical unspliced (presumably for gag, pro, and pol) and singly spliced env mRNAs were detected. In addition, six other virus-specific RNAs were detected that resulted from the use of alternate splice acceptor sites and two premature polyadenylation sites (located in gag and in env). The orf-x gene of the virus appears to be expressed from two singly spliced subgenomic mRNAs of 3.2 kb that would encode an independent orf-x protein of 179 amino acids. In addition, the results suggested that there may also be an internal promoter for orf-x. (C)2002 Elsevier Science (USA).