Characterisation of the 3′-Terminus of Sindbis Virion RNA

Abstract

RECENT studies on the structure of mammalian and viral RNAs have centred on the elucidation of terminal oligonucleotide sequences, since these are accessible for characterisation by several techniques. As a consequence of these studies, several observations on the structure of single- stranded RNAs are possible. The first of these is that plant and phage¹ virion RNAs possess a common 3′-terminal sequence -CpCpCpA_OH except for the case of satellite tobacco necrosis virus² and tobacco rattle virus³ which terminate as -CpCpC_OH. The multipartite, single-stranded RNA genomes of influenza virus⁴ and the RNA tumour viruses⁵ with the possible exception of avian myeloblastosis virus^{6, 7} possess a 3'-terminal uridine residue. The non-segmented, infectious, single-stranded RNA genome of polio-virus contains the 3'-terminal sequence YpGpGp(Ap)₈₉9_OH where Yp indicates a pyrimidine residue⁸.