Nucleotide Sequences of Reovirus Oligonucleotides Evidence for Abortive RNA Synthesis during Virus Maturation

Abstract

IN addition to the ten double stranded segments of genome RNA, reovirions contain many hundreds of single-stranded oligoribonucleotides from 3 to 20 residues long, which fall into two classes. First, those precipitated by acid or ethanol and very rich in adenine^1–2; second, those poorly or not precipitable and therefore shorter, such as the trinucleotidepppGpCpU_OH^3,4. The former class of molecules comprises the fraction previously designated “A-rich RNA”¹, which has been shown to be a component of all three serotypes of human reoviruses², as well as of avian reovirus⁵, irrespective of the nature of the host cell in which the virus was propagated¹. These molecules are synthesized while viral progeny accumulate within the cell¹; they do not appear free in the cytoplasm, but are found only in material which can be pelleted by centrifuging at 20,000g for 30 min¹ with which maturing virus particles are also known to be associated⁶, and the same is probably also true for the second class of oligonucleotides. Although the amount of A-rich oligonucleotides in reovirus is usually constant, the amount of the other oligonucleotides is about five times less in virus grown at 31° C than at 40° C⁷.