Project Details
Use of intron-based RNA systems to study nuclear and cytoplasmic RNA interference processes in plants
Applicant
Privatdozent Dr. Michael Wassenegger
Subject Area
Plant Genetics and Genomics
Term
from 2011 to 2015
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 198472018
We have previously shown that the transcripts of an intronic hairpin RNA (int-hpRNA) transgene construct 1) were retained in the nucleus, 2) were inefficiently processed into small RNAs (sRNAs), 3) efficiently triggered RNA-directed DNA methylation (RdDM) of a transgenic target-promoter but 4) failed to trigger post-transcriptional gene silencing of a transgenic sensor mRNA. In the current proposal, we present how we aim to continue our research on intron-based RNA interference (RNAi) systems. Our studies will be focused on the elucidation of basic aspects of int-hpRNA-mediated gene silencing. However, we will also evaluate the potential of int-hpRNA constructs as a tool for biotechnological applications. By using conventional (non-intronic) hairpins, endogenous promoters have been shown to be poor targets for RdDM and transcriptional gene silencing (TGS). Based on the remarkable precision and efficiency of methylation induced by the int-hpRNA, it is tempting to speculate that int-hpRNA would efficiently initiate RdDM and TGS of endogenous promoters. If so, the intron-based RNAi approach would provide a powerful tool for heritable epigenetic gene silencing. In addition, we aim to take advantage of the intron-based RNAi system to investigate the ambiguous accessibility of introns against RNA-mediated silencing. Finally, the debatable nature of the primary RdDM-trigger (sRNAs or longer RNAs) will be examined by analysing the capacity of the non-small interfering RNA-producing int-hpRNA to trigger RdDM in Dicer-like-deficient plants.
DFG Programme
Research Grants