Transfer RNAs Associated with Vesicular Stomatitis Virus

The predominant RNAs in purified VSV particles are 42S and 4S in size. The 4S RNA is host transfer RNA that did not incorporate detectable radiolabel during VSV infection and was detected by in vitro labelling. Surprisingly, when BHK cells were prelabelled for 30 to 54 h before infection, the incorporation of [3H]uridine and [32P]orthophosphate into virus tRNAs remained very low and virus tRNAs were found to have a 5- to 15-fold lower specific activity than the total host tRNA, the value depending, in part, upon the period of prelabelling. Two-dimensional gel electrophoresis and partial sequence analysis indicated that the virus tRNAs include most species of host tRNA and no singly predominant species was apparent. Transfer RNAs are packaged by several enveloped viruses, but we have not found 4S RNA in reovirus, which lacks an envelope. We suggest that VSV contains a membrane-associated population of tRNA which has a slower rate of turnover than the total population of cellular tRNA.