Project description:DNA methylation in Arabidopsis thaliana is maintained by at least four different enzymes: MET1, CMT3, DRM2, and CMT2. However, DNA methylation is established exclusively by the enzyme DRM2, which acts in the RNA-directed DNA methylation (RdDM) pathway. Some RdDM components belong to gene families and have partially redundant functions, such as DICER-LIKE 2, 3 and 4, and IDN2- LIKE 1 and 2. Traditional mutagenesis screens usually fail to detect genes if they are redundant, since the loss of one gene can be compensated by a related gene. In an effort to circumvent this issue, we utilized co-expression data to identify closely related genes that are co-regulated with genes in the RdDM pathway. Here we report the discovery of two redundant proteins, SNF2-RING-HELICASE-LIKE1 and 2 (FRG1 and 2) that are putative chromatin-related paralogous proteins. Analysis of genome–wide bisulfite sequencing shows that simultaneous mutations of FRG1 and 2 cause broad defects in methylation at RdDM targeted loci. We also show that FRG1 stably associates with Su(var)3-9-related SUVR2, a known RdDM component, in vivo. Combined, our results identify FRG1 and FRG2 as novel components of the RdDM machinery. mRNA profiles of 14 days old seedlings of Columbia 0 wild type and frg1-1 frg2-1 double mutants, 3 biological replicates each.
Project description:DNA methylation in Arabidopsis thaliana is maintained by at least four different enzymes: MET1, CMT3, DRM2, and CMT2. However, DNA methylation is established exclusively by the enzyme DRM2, which acts in the RNA-directed DNA methylation (RdDM) pathway. Some RdDM components belong to gene families and have partially redundant functions, such as DICER-LIKE 2, 3 and 4, and IDN2- LIKE 1 and 2. Traditional mutagenesis screens usually fail to detect genes if they are redundant, since the loss of one gene can be compensated by a related gene. In an effort to circumvent this issue, we utilized co-expression data to identify closely related genes that are co-regulated with genes in the RdDM pathway. Here we report the discovery of two redundant proteins, SNF2-RING-HELICASE-LIKE1 and 2 (FRG1 and 2) that are putative chromatin-related paralogous proteins. Analysis of genomeM-bM-^@M-^Swide bisulfite sequencing shows that simultaneous mutations of FRG1 and 2 cause broad defects in methylation at RdDM targeted loci. We also show that FRG1 stably associates with Su(var)3-9-related SUVR2, a known RdDM component, in vivo. Combined, our results identify FRG1 and FRG2 as novel components of the RdDM machinery. Small RNA profiles of Columbia 0 wild type, frg1-1 frg2-1 double, frg1 to 5 quintuple, suvr2-1, dcl3-1 and drm1-1 drm2-2 double mutants, 3 biological replicates each.
Project description:DNA methylation in Arabidopsis thaliana is maintained by at least four different enzymes: MET1, CMT3, DRM2, and CMT2. However, DNA methylation is established exclusively by the enzyme DRM2, which acts in the RNA-directed DNA methylation (RdDM) pathway. Some RdDM components belong to gene families and have partially redundant functions, such as DICER-LIKE 2, 3 and 4, and IDN2- LIKE 1 and 2. Traditional mutagenesis screens usually fail to detect genes if they are redundant, since the loss of one gene can be compensated by a related gene. In an effort to circumvent this issue, we utilized co-expression data to identify closely related genes that are co-regulated with genes in the RdDM pathway. Here we report the discovery of two redundant proteins, SNF2-RING-HELICASE-LIKE1 and 2 (FRG1 and 2) that are putative chromatin-related paralogous proteins. Analysis of genome–wide bisulfite sequencing shows that simultaneous mutations of FRG1 and 2 cause broad defects in methylation at RdDM targeted loci. We also show that FRG1 stably associates with Su(var)3-9-related SUVR2, a known RdDM component, in vivo. Combined, our results identify FRG1 and FRG2 as novel components of the RdDM machinery.
Project description:DNA methylation in Arabidopsis thaliana is maintained by at least four different enzymes: MET1, CMT3, DRM2, and CMT2. However, DNA methylation is established exclusively by the enzyme DRM2, which acts in the RNA-directed DNA methylation (RdDM) pathway. Some RdDM components belong to gene families and have partially redundant functions, such as DICER-LIKE 2, 3 and 4, and IDN2- LIKE 1 and 2. Traditional mutagenesis screens usually fail to detect genes if they are redundant, since the loss of one gene can be compensated by a related gene. In an effort to circumvent this issue, we utilized co-expression data to identify closely related genes that are co-regulated with genes in the RdDM pathway. Here we report the discovery of two redundant proteins, SNF2-RING-HELICASE-LIKE1 and 2 (FRG1 and 2) that are putative chromatin-related paralogous proteins. Analysis of genome–wide bisulfite sequencing shows that simultaneous mutations of FRG1 and 2 cause broad defects in methylation at RdDM targeted loci. We also show that FRG1 stably associates with Su(var)3-9-related SUVR2, a known RdDM component, in vivo. Combined, our results identify FRG1 and FRG2 as novel components of the RdDM machinery.
Project description:DNA methylation in Arabidopsis thaliana is maintained by at least four different enzymes MET1, CMT3, DRM2 and CMT2. However, new methylation patterns are established exclusively by the enzyme DRM2, which acts within a pathway termed RNA-directed DNA methylation (RdDM). Some RdDM components belong to gene families and have partially redundant functions (i.e. DICER LIKE 2, 3 and 4 and IDN2 PARALOG 1 and 2). Traditional screens, which usually affect single genes, usually fail to detect genes if they are redundant, since the loss of one gene is compensated by a related gene. In an effort to circumvent this caveat, we utilized co-expression data to identify closely related genes that are co-regulated with genes in the RdDM pathway. We report the discovery of two redundant proteins, SNF2-RING-HELICASE1 and 2 (FRINGE1 and 2) that are putative chromatin-related paralogous proteins. Analysis of genome–wide bisulfite sequencing shows that simultaneous mutations of FRINGE1 and 2 cause broad defects in methylation at RdDM targeted loci. We also show that FRINGE1 stably associates with Su(var)3-9-related SUVR2, a known RdDM component, in vivo. Combined our results identify FRINGE1 and FRINGE2 as novel components of the RdDM machinery. One fringe 1/2 sample analyzed.
Project description:Plants as sessile organisms can adapt to environmental stress to mitigate its adverse effects. As part of such adaptation they maintain an active memory of heat stress for several days that mediates a more efficient response to recurring stress. We identified a mutant that is specifically affected in this heat stress memory. The forgetter1 (frg1) mutant is defective in the Arabidopsis orthologue of Strawberry notch and displays reduced maintenance of heat-induced gene expression. FRG1 globally associates with the promoter region of actively expressed genes in a heat-dependent fashion. FRG1 interacts with chromatin remodelers of the SWI/SNF and ISWI families, which also display reduced heat stress memory. Accordingly, nucleosome dynamics at loci with altered maintenance of heat-induced expression are affected in frg1. Thus, FRG1 is required to sustain a transcription-competent chromatin environment by nucleosome positioning. Our findings suggest a mechanism for the highly conserved Strawberry notch proteins in development and pathologies.
Project description:The in vivo role of a novel domain in Swi2/Snf2 required for its function was investigated using microarray analysis. The effect of domain deletions of Swi2/Snf2 on expression changes were studied. The ?SnAC strain, along with ?snf2 and wild type strains (BY4741 and Snf2-2FLAG, PSY2), were analyzed by genome-wide expression profiling with DNA microarrays. The method has been described in Chitikila et al., Mol. Cell, 10:871-882, 2002 (PMID 12419230).
Project description:DNA methylation in Arabidopsis thaliana is maintained by at least four different enzymes MET1, CMT3, DRM2 and CMT2. However, new methylation patterns are established exclusively by the enzyme DRM2, which acts within a pathway termed RNA-directed DNA methylation (RdDM). Some RdDM components belong to gene families and have partially redundant functions (i.e. DICER LIKE 2, 3 and 4 and IDN2 PARALOG 1 and 2). Traditional screens, which usually affect single genes, usually fail to detect genes if they are redundant, since the loss of one gene is compensated by a related gene. In an effort to circumvent this caveat, we utilized co-expression data to identify closely related genes that are co-regulated with genes in the RdDM pathway. We report the discovery of two redundant proteins, SNF2-RING-HELICASE1 and 2 (FRINGE1 and 2) that are putative chromatin-related paralogous proteins. Analysis of genome–wide bisulfite sequencing shows that simultaneous mutations of FRINGE1 and 2 cause broad defects in methylation at RdDM targeted loci. We also show that FRINGE1 stably associates with Su(var)3-9-related SUVR2, a known RdDM component, in vivo. Combined our results identify FRINGE1 and FRINGE2 as novel components of the RdDM machinery.