Relationship of 2',3'-cyclic nucleotide 3'-phosphohydrolase activity of large enveloped RNA viruses to host cell...

Purified virions of the large RNA viruses show 2',3'-cyclic nucleotide 3'-phosphohydrolase (3'-CNPase) activity. The 3'-CNPase activity is virion-associated and stimulated by their treatment with nonionic detergents. Cytopathic viruses such as influenza A2 (Singapore/57), NDV, and VSV showed the specific activity of a virion-associated 3'-CNPase equal to or lower than the specific activity of host cell enzyme. Retroviruses are an example of extreme relationship of 3'-CNPase to virion. With the AMV-BAI-A associated enzyme activity increased after Triton X-100 treatment ten times more than that associated with other viruses examined. The specific activity of virus-associated 3'-CNPase was 16-28 times higher than that in chick myeloblasts. BLV showed a very low enzyme activity. The correlation between the activity of cellular 3'-CNPase and virus yield showed that 3'-CNPase could belong to cellular factors influencing virus replication.