The splicing factor SR45 affects the RNA-directed DNA methylation pathway in Arabidopsis |
| |
| Authors: | Israel Ausin Maxim VC Greenberg Carey Fei Li Steven E Jacobsen |
| |
| Institution: | 1.Department of Molecular, Cell and Developmental Biology; University of California Los Angeles; Los Angeles, CA USA;2.Department of Plant Molecular Genetics; Campus Universidad Autonoma de Madrid; Madrid, Spain;3.Department of Neurology; Institute for Immunology; University of California Irvine; Irvine, CA USA;4.Howard Hughes Medical Institute; University of California Los Angeles; Los Angeles, CA USA |
| |
| Abstract: | Cytosine DNA methylation is an epigenetic mark frequently associated with silencing of genes and transposons. In Arabidopsis, the establishment of cytosine DNA methylation is performed by DOMAINS REARRANGED METHYLTRANSFERASE 2 (DRM2). DRM2 is guided to target sequences by small interfering RNAs (siRNAs) in a pathway termed RNA-directed DNA methylation (RdDM). We performed a screen for mutants that affect the establishment of DNA methylation by investigating genes that contain predicted RNA-interacting domains. After transforming FWA into 429 T-DNA insertion lines, we assayed for mutants that exhibited a late-flowering phenotype due to hypomethylated, thus ectopically expressed, copies of FWA. A T-DNA insertion line within the coding region of the spliceosome gene SR45 (sr45-1) flowered late after FWA transformation. Additionally, sr45-1 mutants display defects in the maintenance of DNA methylation. DNA methylation establishment and maintenance defects present in sr45-1 mutants are enhanced in dcl3-1 mutant background, suggesting a synergistic cooperation between SR45 and DICER-LIKE3 (DCL3) in the RdDM pathway. |
| |
| Keywords: | Arabidopsis de novo DNA Methylation genetic screen siRNA |
|
|
