Characterization of a Satellite RNA Associated with Pea Enation Mosaic Virus

• Published in: Journal of general virology 1989-05, Vol.70 (5), p.1075-1084
• Main Authors: Demler, S. A, De Zoeten, G. A
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Microbiology; pea enation mosaic virus; Replicative cycle, interference, host-virus relations, pathogenicity, miscellaneous strains; Virology
• ISSN: 0022-1317; 1465-2099
• DOI: 10.1099/0022-1317-70-5-1075

Department of Plant Pathology, University of Wisconsin, Madison, Wisconsin 53706, U.S.A. The bipartite genome of pea enation mosaic virus (PEMV) is often accompanied by a non-essential third RNA ( M r 0.3 x 10 6 ) of unknown origin and function. Although the Wisconsin strains of PEMV originally lacked this RNA, we have monitored the appearance of a putative replicative form of this species in PEMV-infected tissue. In later generations encapsidated single-stranded RNA 3 appeared. We have used a 750 bp clone generated against the ds replicative form of RNA 3 to probe viral and host-derived nucleic acids to establish the relationship of this RNA to PEMV infection. Northern blot analysis showed that RNA 3 is distinct from viral genomic RNA and from host RNA. Similarly, Southern blot analysis showed that RNA 3 is distinct from the host genome. Infectivity analysis of fractionated viral RNAs coupled with Northern blot analysis confirmed that RNA 3 is both non-essential for PEMV infection, and non-infectious when inoculated on its own. RNA 3 does not influence symptom expression, aphid transmission or particle morphology. We conclude that RNA 3 of PEMV is a satellite RNA. Keywords: pea enation mosaic virus, satellite RNA Received 2 November 1988; accepted 18 January 1989.