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Updated: Jun 3, 2026

Bacterial Artificial Chromosomes: A Functional Genomics Tool for the Study of Positive-strand RNA Viruses
Published on: December 29, 2015
Subgenomic messenger RNAs: mastering regulation of (+)-strand RNA virus life cycle
Joanna Sztuba-Solińska1, Victor Stollar, Jozef J Bujarski
1Plant Molecular Biology Center and the Department of Biological Sciences, Northern Illinois University, De Kalb, IL 60115, USA.
Abstract:
Many (+)-strand RNA viruses use subgenomic (SG) RNAs as messengers for protein expression, or to regulate their viral life cycle. Three different mechanisms have been described for the synthesis of SG RNAs. The first mechanism involves internal initiation on a (-)-strand RNA template and requires an internal SGP promoter. The second mechanism makes a prematurely terminated (-)-strand RNA which is used as template to make the SG RNA. The third mechanism uses discontinuous RNA synthesis while making the (-)-strand RNA templates. Most SG RNAs are translated into structural proteins or proteins related to pathogenesis: however other SG RNAs regulate the transition between translation and replication, function as riboregulators of replication or translation, or support RNA-RNA recombination. In this review we discuss these functions of SG RNAs and how they influence viral replication, translation and recombination.
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