DICER-LIKE2 plays a primary role in transitive silencing of transgenes in Arabidopsis.

Dicer-like (DCL) enzymes play a pivotal role in RNA silencing in plants, processing the long double-stranded RNA (dsRNA) that triggers silencing into the primary short interfering RNAs (siRNAs) that mediate it. The siRNA population can be augmented and silencing amplified via transitivity, an RNA-de...

Full description

Bibliographic Details
Main Authors: Sizolwenkosi Mlotshwa, Gail J Pruss, Angela Peragine, Matthew W Endres, Junjie Li, Xuemei Chen, R Scott Poethig, Lewis H Bowman, Vicki Vance
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2008-03-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC2262140?pdf=render
id doaj-458928539e7f4d8abb9ffb4735f58bed
record_format Article
spelling doaj-458928539e7f4d8abb9ffb4735f58bed2020-11-25T01:48:34ZengPublic Library of Science (PLoS)PLoS ONE1932-62032008-03-0133e175510.1371/journal.pone.0001755DICER-LIKE2 plays a primary role in transitive silencing of transgenes in Arabidopsis.Sizolwenkosi MlotshwaGail J PrussAngela PeragineMatthew W EndresJunjie LiXuemei ChenR Scott PoethigLewis H BowmanVicki VanceDicer-like (DCL) enzymes play a pivotal role in RNA silencing in plants, processing the long double-stranded RNA (dsRNA) that triggers silencing into the primary short interfering RNAs (siRNAs) that mediate it. The siRNA population can be augmented and silencing amplified via transitivity, an RNA-dependent RNA polymerase (RDR)-dependent pathway that uses the target RNA as substrate to generate secondary siRNAs. Here we report that Arabidopsis DCL2-but not DCL4-is required for transitivity in cell-autonomous, post-transcriptional silencing of transgenes. An insertion mutation in DCL2 blocked sense transgene-induced silencing and eliminated accumulation of the associated RDR-dependent siRNAs. In hairpin transgene-induced silencing, the dcl2 mutation likewise eliminated accumulation of secondary siRNAs and blocked transitive silencing, but did not block silencing mediated by primary siRNAs. Strikingly, in all cases, the dcl2 mutation eliminated accumulation of all secondary siRNAs, including those generated by other DCL enzymes. In contrast, mutations in DCL4 promoted a dramatic shift to transitive silencing in the case of the hairpin transgene and enhanced silencing induced by the sense transgene. Suppression of hairpin and sense transgene silencing by the P1/HC-Pro and P38 viral suppressors was associated with elimination of secondary siRNA accumulation, but the suppressors did not block processing of the stem of the hairpin transcript into primary siRNAs. Thus, these viral suppressors resemble the dcl2 mutation in their effects on siRNA biogenesis. We conclude that DCL2 plays an essential, as opposed to redundant, role in transitive silencing of transgenes and may play a more important role in silencing of viruses than currently thought.http://europepmc.org/articles/PMC2262140?pdf=render
collection DOAJ
language English
format Article
sources DOAJ
author Sizolwenkosi Mlotshwa
Gail J Pruss
Angela Peragine
Matthew W Endres
Junjie Li
Xuemei Chen
R Scott Poethig
Lewis H Bowman
Vicki Vance
spellingShingle Sizolwenkosi Mlotshwa
Gail J Pruss
Angela Peragine
Matthew W Endres
Junjie Li
Xuemei Chen
R Scott Poethig
Lewis H Bowman
Vicki Vance
DICER-LIKE2 plays a primary role in transitive silencing of transgenes in Arabidopsis.
PLoS ONE
author_facet Sizolwenkosi Mlotshwa
Gail J Pruss
Angela Peragine
Matthew W Endres
Junjie Li
Xuemei Chen
R Scott Poethig
Lewis H Bowman
Vicki Vance
author_sort Sizolwenkosi Mlotshwa
title DICER-LIKE2 plays a primary role in transitive silencing of transgenes in Arabidopsis.
title_short DICER-LIKE2 plays a primary role in transitive silencing of transgenes in Arabidopsis.
title_full DICER-LIKE2 plays a primary role in transitive silencing of transgenes in Arabidopsis.
title_fullStr DICER-LIKE2 plays a primary role in transitive silencing of transgenes in Arabidopsis.
title_full_unstemmed DICER-LIKE2 plays a primary role in transitive silencing of transgenes in Arabidopsis.
title_sort dicer-like2 plays a primary role in transitive silencing of transgenes in arabidopsis.
publisher Public Library of Science (PLoS)
series PLoS ONE
issn 1932-6203
publishDate 2008-03-01
description Dicer-like (DCL) enzymes play a pivotal role in RNA silencing in plants, processing the long double-stranded RNA (dsRNA) that triggers silencing into the primary short interfering RNAs (siRNAs) that mediate it. The siRNA population can be augmented and silencing amplified via transitivity, an RNA-dependent RNA polymerase (RDR)-dependent pathway that uses the target RNA as substrate to generate secondary siRNAs. Here we report that Arabidopsis DCL2-but not DCL4-is required for transitivity in cell-autonomous, post-transcriptional silencing of transgenes. An insertion mutation in DCL2 blocked sense transgene-induced silencing and eliminated accumulation of the associated RDR-dependent siRNAs. In hairpin transgene-induced silencing, the dcl2 mutation likewise eliminated accumulation of secondary siRNAs and blocked transitive silencing, but did not block silencing mediated by primary siRNAs. Strikingly, in all cases, the dcl2 mutation eliminated accumulation of all secondary siRNAs, including those generated by other DCL enzymes. In contrast, mutations in DCL4 promoted a dramatic shift to transitive silencing in the case of the hairpin transgene and enhanced silencing induced by the sense transgene. Suppression of hairpin and sense transgene silencing by the P1/HC-Pro and P38 viral suppressors was associated with elimination of secondary siRNA accumulation, but the suppressors did not block processing of the stem of the hairpin transcript into primary siRNAs. Thus, these viral suppressors resemble the dcl2 mutation in their effects on siRNA biogenesis. We conclude that DCL2 plays an essential, as opposed to redundant, role in transitive silencing of transgenes and may play a more important role in silencing of viruses than currently thought.
url http://europepmc.org/articles/PMC2262140?pdf=render
work_keys_str_mv AT sizolwenkosimlotshwa dicerlike2playsaprimaryroleintransitivesilencingoftransgenesinarabidopsis
AT gailjpruss dicerlike2playsaprimaryroleintransitivesilencingoftransgenesinarabidopsis
AT angelaperagine dicerlike2playsaprimaryroleintransitivesilencingoftransgenesinarabidopsis
AT matthewwendres dicerlike2playsaprimaryroleintransitivesilencingoftransgenesinarabidopsis
AT junjieli dicerlike2playsaprimaryroleintransitivesilencingoftransgenesinarabidopsis
AT xuemeichen dicerlike2playsaprimaryroleintransitivesilencingoftransgenesinarabidopsis
AT rscottpoethig dicerlike2playsaprimaryroleintransitivesilencingoftransgenesinarabidopsis
AT lewishbowman dicerlike2playsaprimaryroleintransitivesilencingoftransgenesinarabidopsis
AT vickivance dicerlike2playsaprimaryroleintransitivesilencingoftransgenesinarabidopsis
_version_ 1725011354041974784