Proteins
Curated comments from UniProt
Type | Comment | Proteins |
---|---|---|
AGO4_ARATH | function | Together with RDM3, required for transcriptional gene silencing (TGS) by DNA methylation and repressive histone modifications (H3K9me2) of several chromatin loci (PubMed:21738482). Component of the RISC complex that associate with the small interfering RNA (siRNA) pathway involved in direct cytosine methylation at endogenous DNA repeats. Forms a AGO4/NRPE1/siRNA complex in cajal body, facilitating its function in RNA-directed gene silencing of target loci. Required for CpNpG and asymmetric DNA methylation as well as histone H3 'Lys-9' methylation (H3K9me) at SUP and SN1 loci. May be not required for CpG methylation. Required for the production and maintenance of retrotransposon SN1 and Copia and ribosomal 5S 25 nucleotide siRNAs specialized in gene silencing at chromatin level. Involved in de novo methylation of FWA gene and required for the maintenance of RNA-directed DNA methylation (RdDM) triggered by inverted repeat transgenes. Interacts with miRNA miR390 and miR172, targeting respectively TAS3 and AP2 mRNAs, and mediates cleavage of miRNA targets. Associates mainly with small RNAs of 24 nucleotide in length and preferentially recruits small RNAs with a 5' terminal adenosine. Targeted by the turnip yellows virus (TuYV) protein P0 (via F-box-like domain) for probable proteasome degradation and thereby inactivating AGO4 function in RNA silencing. Required for resistance to the bacterial pathogen P.syringae. Works independently of the RdDM pathway in mediating resistance to P.syringae. RdDM is involved in viral genome methylation as an epigenetic defense against geminiviruses (PubMed:12522258, PubMed:14988555, PubMed:15242620, PubMed:16839878, PubMed:16839879, PubMed:16998468, PubMed:17869110, PubMed:17938239, PubMed:17993621, PubMed:18342361, PubMed:18596098, PubMed:19377477, PubMed:20173091). |
AGO4_ARATH | similarity | Belongs to the argonaute family. Ago subfamily. |
AGO4_ARATH | subcellular location | Also located in AB-bodies that are distincts from the Cajal bodies and immediately adjacent to the condensed 45S ribosomal DNA (rDNA) loci (PubMed:18266474). Colocalizes with AGO4 and polymerase V in the nucleoplasm (PubMed:19410546). |
AGO4_ARATH | tissue specificity | Expressed in embryos, mature leaves, vascular tissue of the sepals, stamens and stigma, at the tip of the style and siliques. |
Function
Gene Ontology
cellular component | |
---|---|
nucleolus | ECO |
Cajal body | ECO |
ribonucleoprotein complex | ECO |
cytoplasmic ribonucleoprotein granule | ECO |
nucleoplasm | ECO |
euchromatin | ECO |
molecular function | |
chromatin binding | ECO |
miRNA binding | ECO |
siRNA binding | ECO |
RNA endonuclease activity | ECO |
biological process | |
defense response to virus | ECO |
gene silencing by siRNA-directed DNA methylation | ECO |
heterochromatin formation | ECO |
modulation by virus of host process | ECO |
siRNA processing | ECO |
defense response to bacterium | ECO |
regulatory ncRNA-mediated heterochromatin formation | ECO |
regulation of translation | ECO |