Citrus Sinensis ID: 002802

Annotation transfered from Closely Related SWISS-PROT Entries

Annotation	Function Description	Confidence Level	Reference Protein
Protein argonaute 4	Involved in transcriptional gene silencing (TGS). 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.	confident	Q9ZVD5
Protein argonaute 4B	Probably involved in the RNA silencing pathway. May bind to short RNAs such as microRNAs (miRNAs) or short interfering RNAs (siRNAs), and represses the translation of mRNAs which are complementary to them.	confident	Q0JF58
Protein argonaute-2	Required for RNA-mediated gene silencing (RNAi) by the RNA-induced silencing complex (RISC). The 'minimal RISC' appears to include EIF2C2/AGO2 bound to a short guide RNA such as a microRNA (miRNA) or short interfering RNA (siRNA). These guide RNAs direct RISC to complementary mRNAs that are targets for RISC-mediated gene silencing. The precise mechanism of gene silencing depends on the degree of complementarity between the miRNA or siRNA and its target. Binding of RISC to a perfectly complementary mRNA generally results in silencing due to endonucleolytic cleavage of the mRNA specifically by EIF2C2/AGO2. Binding of RISC to a partially complementary mRNA results in silencing through inhibition of translation, and this is independent of endonuclease activity. May inhibit translation initiation by binding to the 7-methylguanosine cap, thereby preventing the recruitment of the translation initiation factor eIF4-E. May also inhibit translation initiation via interaction with EIF6, which itself binds to the 60S ribosomal subunit and prevents its association with the 40S ribosomal subunit. The inhibition of translational initiation leads to the accumulation of the affected mRNA in cytoplasmic processing bodies (P-bodies), where mRNA degradation may subsequently occur. In some cases RISC-mediated translational repression is also observed for miRNAs that perfectly match the 3' untranslated region (3'-UTR). Can also up-regulate the translation of specific mRNAs under certain growth conditions. Binds to the AU element of the 3'-UTR of the TNF (TNF-alpha) mRNA and up-regulates translation under conditions of serum starvation. Also required for transcriptional gene silencing (TGS), in which short RNAs known as antigene RNAs or agRNAs direct the transcriptional repression of complementary promoter regions.	probable	Q9QZ81

Prediction of Enzyme Commission Number

No EC number assigned to the protein, probably not an enzyme!

Spatial Structural Prediction

Templates for Structure Prediction

ID	Alignment Graph	Confidence Level	View Alignment and Template
Query
4f1n, chain A		confident	Alignment | Template Structure