Back to Search
Start Over
DRD1-Pol V-dependent self-silencing of an exogenous silencer restricts the non-cell autonomous silencing of an endogenous target gene.
- Source :
-
Plant Journal . Nov2011, Vol. 68 Issue 4, p633-645. 13p. - Publication Year :
- 2011
-
Abstract
- Summary In plants, the exogenous transgene transcribing inverted-repeat (exo- IR) sequences produces double-stranded RNAs that are processed by DCL4. The 21-nt small interfering RNAs generated function as mobile signals to trigger non-cell autonomous silencing of target endogenes in the neighboring 10-15 cells. The potential involvement of nuclear silencing pathway components in signal spreading or sensing in target cells is not clear. Here, we demonstrate that the exo- IR silencer (exo- Pdsi) is negatively autoregulated through methylation spreading, which acts in cis to reinforce the self-silencing of the silencer. Mutations affecting nuclear proteins DRD1 and Pol V (NRPE1 or NRPD2) relieved exo- Pdsi self-silencing, resulting in higher levels of Pdsi transcripts, which increased the non-cell autonomous silencing of endo- PDS. Our results suggest that in an experimental silencing pathway, methylation spreading on a silencer transgene may not have a direct endogenous plant counterpart when the protein-encoding gene is the target. DRD1-Pol V-dependent de novo methylation, by acting in cis to reinforce self-silencing of exo- IR, may play a role in restraining the inappropriate silencing of active protein-coding genes in plants. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 09607412
- Volume :
- 68
- Issue :
- 4
- Database :
- Academic Search Index
- Journal :
- Plant Journal
- Publication Type :
- Academic Journal
- Accession number :
- 67110761
- Full Text :
- https://doi.org/10.1111/j.1365-313X.2011.04714.x