TRANSDUCTION OF A HUMAN RNA SEQUENCE BY POLIOVIRUS

Cells infected with poliovirus express a virally encoded polyprotein w hich undergoes self-mediated cleavage into structural and nonstructura l viral proteins. Most of these cleavages are catalyzed by the 3C prot eolytic domain of the polyprotein. Polyprotein synthesized in vitro fr om an RNA template containing a three-nucleotide insertion in 3C under went proteolytic processing at all but one of the 3C-dependent cleavag e sites. When transfected into HeLa cells, this RNA template displayed a lethal phenotype. We report here the isolation of two pseudoreverta nt progeny strains with restored protein-processing phenotypes, one of which appears to have arisen by transduction of a stretch of nucleoti des from human 28S rRNA.