Stacey D W, Allfrey V G, Hanafusa H
Proc Natl Acad Sci U S A. 1977 Apr;74(4):1614-8. doi: 10.1073/pnas.74.4.1614.
Virion RNA from the avian leukosis virus Rous-associated virus 2 (RAV-2) and poly(A)-containing RNAs from RAV-2-infected chick embryo fibroblasts were microinjected into fibroblasts transformed by the Bryan high-titer strain of Rous sarcoma virus (RSV), which is deficient in viral envelope glycoprotein. Production of infectious RSV following these injections depended upon the viral envelope-messenger activity of the injected RNA. This system constituted a sensitive and rigorous assay system for viral envelope-messenger RNA. It was found that 21S mRNA from RAV-2-infected cells expressed the highest activity, while 35S mRNA expressed comparatively little. In addition, RAV-2-virion RNA expressed little messenger activity. The rate of formation of infectious RSV following 21S mRNA injections reached a peak near 9 hr, which was followed by a rapid decline. Evidence has been obtained that a small fraction of both 35S virion RNA and 35S mRNA from virus-infected cells was encapsulated into virus particles following their injection into virus-producing cells.