Abstract
A kinetic analysis of formation of Semliki Forest virus-specific RNAs revealed that 22 S RNA was synthesized first and accumulated within or on a structure not disrupted by homogenization, but disrupted by detergent treatment, presumably a lipid-containing membrane or vesicle. When sampled at the end of the latent period of virus growth the 22 S RNA consisted of a mixture of two RNAs, double- and single-stranded. The amount of double-stranded 22 S RNA remained constant thereafter with no complementary RNA synthesized after the latent period of virus growth.
Appearing during the latter portion of the latent period were 26 S RNAs and 42 S virus RNA. The rate at which 26 S RNA accumulated remained constant throughout infection thereafter, whereas that of 42 S virus RNA was maximal at the time of maximal virus accumulation.
* Present address: Department of Virology, University of Helsinki, Haartmaninkatu 3, Helsinki 25, Finland.