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Bacterial Artificial Chromosomes: A Functional Genomics Tool for the Study of Positive-strand RNA Viruses
Published on: December 29, 2015
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Structural and functional analysis of viral siRNAs
Gyorgy Szittya1, Simon Moxon, Vitantonio Pantaleo
1School of Biological Sciences, University of East Anglia, Norwich, United Kingdom.
Plos Pathogens
|April 7, 2010
Summary
Plant virus-derived short interfering RNAs (vsiRNAs) are abundant but poorly understood. This study reveals vsiRNAs originate from structured viral RNA, not double-stranded RNA, with implications for RNA silencing mechanisms.
Area of Science:
- Plant virology
- RNA biology
- Bioinformatics
Background:
- Plant viruses generate abundant short interfering RNAs (vsiRNAs) during infection.
- The precise function, structure, and biogenesis of these vsiSIRNAs remain largely uncharacterized.
Purpose of the Study:
- To elucidate the origin and characteristics of vsiRNAs produced during plant virus infection.
- To compare different high-throughput sequencing and hybridization methods for vsiRNA profiling.
- To investigate the 5' end structure and duplex nature of vsiRNAs.
Main Methods:
- Profiling of vsiRNAs using Solexa and 454 high-throughput sequencing platforms.
- Hybridization-based array approach for vsiRNA profiling.
- Enzymatic analysis using Terminator 5'-Phosphate-Dependent Exonuclease.
- Analysis of vsiRNA targeting efficiency using sensor constructs.
Main Results:
- Deep sequencing revealed a strong bias for the positive strand of the virus and identified highly abundant vsiRNA-producing regions.
- Hybridization results were consistent across plant species and independent of RDR6.
- Terminator exonuclease assays indicated most vsiRNAs possess 5' monophosphates and are not perfect duplexes.
- Targeting efficiency was similar for regions recognized by abundant and non-abundant vsiRNAs.
Conclusions:
- Different high-throughput sequencing techniques exhibit distinct biases, affecting short RNA profiles.
- The Terminator assay requires careful optimization (denaturation, dilution) to avoid misleading results.
- Evidence suggests vsiRNAs are derived from structured positive-sense viral RNA, not double-stranded RNA or via RNA-dependent RNA polymerase.
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