Project description:Chemical cross-linking coupled to mass spectrometry was used to study the A. thaliana DDR complex consisting of DMS3, RMD1 and a peptide from the interaction region of DRD1. Cross-linking was performed using different cross-linking chemistries: disuccinimidyl suberate (DSS) and a combination of adipic acid dihydrazide (ADH) and the coupling reagent, DMTMM.
Project description:This SuperSeries is composed of the following subset Series: GSE36129: An IDN2-containing complex involved in RNA-directed DNA methylation in Arabidopsis [leaves RNA-seq] GSE36143: An IDN2-containing complex involved in RNA-directed DNA methylation in Arabidopsis [BS-seq] GSE37206: An IDN2-containing complex involved in RNA-directed DNA methylation in Arabidopsis [flowers RNA-seq] Refer to individual Series
Project description:The Microrchidia (MORC) family of ATPases are required for transposable element (TE) silencing and heterochromatin condensation in plants and animals, and C. elegans MORC-1 has been shown to topologically entrap and condense DNA. In Arabidopsis thaliana, mutation of MORCs has been shown to reactivate silent methylated genes and transposons and to decondense heterochromatic chromocenters, despite only minor changes in the maintenance of DNA methylation. Here we provide the first evidence localizing Arabidopsis MORC proteins to specific regions of chromatin and find that MORC4 and MORC7 are closely co-localized with sites of RNA directed DNA methylation (RdDM). We further show that MORC7, when tethered to DNA by an artificial zinc finger, can facilitate the establishment of RdDM. Finally, we show that MORCs are required for the efficient RdDM mediated establishment of DNA methylation and silencing of a newly integrated FWA transgene, even though morc mutations have no effect on the maintenance of preexisting methylation at the endogenous FWA gene. We propose that MORCs function as a molecular tether in RdDM complexes to reinforce RdDM activity for methylation establishment. These findings have implications for MORC protein function in a variety of other eukaryotic organisms.