Related Experiment Video
Updated: Jul 18, 2026

MicroRNA-based Regulation of Picornavirus Tropism
Published on: February 6, 2017
A multicomponent RNA-based control system regulates subgenomic mRNA transcription in a tombusvirus
Han-Xin Lin1, Wei Xu, K Andrew White
1Department of Biology, York University, 4700 Keele St., Toronto, Ontario, Canada M3J 1P3.
Abstract:
During infections, positive-strand RNA tombusviruses transcribe two subgenomic (sg) mRNAs that allow for the expression of a subset of their genes. This process is thought to involve an unconventional mechanism involving the premature termination of the virally encoded RNA-dependent RNA polymerase while it is copying the virus genome. The 3' truncated minus strands generated by termination are then used as templates for sg mRNA transcription. In addition to requiring an extensive network of long-distance RNA-RNA interactions (H.-X. Lin and K. A. White, EMBO J. 23:3365-3374, 2004), the transcription of tombusvirus sg mRNAs also involves several additional RNA structures. In vivo analysis of these diverse RNA elements revealed that they function at distinct steps in the process by facilitating the formation or stabilization of the long-distance interactions, modulating minus-strand template production, or promoting the initiation of sg mRNA transcription. All of the RNA elements characterized could be readily incorporated into a premature termination model for sg mRNA transcription. Overall, the analyses revealed a complex system that displays a high level of structural integration and functional coordination. This multicomponent RNA-based control system may serve as a useful paradigm for understanding related transcriptional processes in other positive-sense RNA viruses.
More Related Videos
10:11Modeling The Lifecycle Of Ebola Virus Under Biosafety Level 2 Conditions With Virus-like Particles Containing Tetracistronic Minigenomes
Published on: September 27, 2014
09:26DNA-Tethered RNA Polymerase for Programmable In vitro Transcription and Molecular Computation
Published on: December 29, 2021
Related Concept Videos
Transcriptional Regulation: Riboswitches
Regulation of Expression at Multiple Steps
siRNA - Small Interfering RNAs
In the cytoplasm, siRNA is processed from a double-stranded RNA, which comes from either endogenous DNA transcription or exogenous sources like a virus. This double-stranded RNA is then cleaved by the ATP-dependent...
Regulation of Expression Occurs at Multiple Steps
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
Viruses with RNA Genomes
Leaky Scanning