Gene Symbol: AGO4
Description: Argonaute family protein
Alias: ARGONAUTE 4, OCP11, OVEREXPRESSOR OF CATIONIC PEROXIDASE 11, T20P8.9, T20P8_9, Argonaute family protein
Species: thale cress
Products:     AGO4

Top Publications

  1. Brosnan C, Mitter N, Christie M, Smith N, Waterhouse P, Carroll B. Nuclear gene silencing directs reception of long-distance mRNA silencing in Arabidopsis. Proc Natl Acad Sci U S A. 2007;104:14741-6 pubmed
    ..A mutant representing a fourth gene in the pathway, argonaute4 (ago4), was also partially compromised in the reception of silencing...
  2. Wierzbicki A, Ream T, Haag J, Pikaard C. RNA polymerase V transcription guides ARGONAUTE4 to chromatin. Nat Genet. 2009;41:630-4 pubmed publisher
    ..In Arabidopsis, this process involves 24-nt siRNAs that bind to ARGONAUTE4 (AGO4) and facilitate the targeting of complementary loci via unknown mechanisms...
  3. Bies Etheve N, Pontier D, Lahmy S, Picart C, Vega D, Cooke R, et al. RNA-directed DNA methylation requires an AGO4-interacting member of the SPT5 elongation factor family. EMBO Rep. 2009;10:649-54 pubmed publisher a model to detect new components in plant RNA silencing pathways, we identified SPT5-like, a plant-specific AGO4-interacting member of the nuclear SPT5 (Suppressor of Ty insertion 5) RNA polymerase (RNAP) elongation factor ..
  4. He X, Hsu Y, Zhu S, Wierzbicki A, Pontes O, Pikaard C, et al. An effector of RNA-directed DNA methylation in arabidopsis is an ARGONAUTE 4- and RNA-binding protein. Cell. 2009;137:498-508 pubmed publisher
    ..KTF1 colocalizes with ARGONAUTE 4 (AGO4) in punctate nuclear foci and binds AGO4 and RNA transcripts...
  5. Qi Y, He X, Wang X, Kohany O, Jurka J, Hannon G. Distinct catalytic and non-catalytic roles of ARGONAUTE4 in RNA-directed DNA methylation. Nature. 2006;443:1008-12 pubmed
    ..This requires a specialized set of RNAi components, including ARGONAUTE4 (AGO4)...
  6. Zheng X, Zhu J, Kapoor A, Zhu J. Role of Arabidopsis AGO6 in siRNA accumulation, DNA methylation and transcriptional gene silencing. EMBO J. 2007;26:1691-701 pubmed
    ..In Arabidopsis, except for AGO1, AGO4 and AGO7, the roles of seven other AGOs in gene silencing are not known...
  7. He X, Hsu Y, Pontes O, Zhu J, Lu J, Bressan R, et al. NRPD4, a protein related to the RPB4 subunit of RNA polymerase II, is a component of RNA polymerases IV and V and is required for RNA-directed DNA methylation. Genes Dev. 2009;23:318-30 pubmed publisher
    ..ros1, we identified a new component (referred to as RDM2) as well as seven known components (NRPD1, NRPE1, NRPD2a, AGO4, HEN1, DRD1, and HDA6) of the RdDM pathway...
  8. Li C, Henderson I, Song L, Fedoroff N, Lagrange T, Jacobsen S. Dynamic regulation of ARGONAUTE4 within multiple nuclear bodies in Arabidopsis thaliana. PLoS Genet. 2008;4:e27 pubmed publisher
    DNA methylation directed by 24-nucleotide small RNAs involves the small RNA-binding protein ARGONAUTE4 (AGO4), and it was previously shown that AGO4 localizes to nucleolus-adjacent Cajal bodies, sites of snRNP complex maturation...
  9. Havecker E, Wallbridge L, Hardcastle T, Bush M, Kelly K, Dunn R, et al. The Arabidopsis RNA-directed DNA methylation argonautes functionally diverge based on their expression and interaction with target loci. Plant Cell. 2010;22:321-34 pubmed publisher
    ..the basis of AGO functional diversification, we characterized three closely related Arabidopsis thaliana AGOs (AGO4, AGO6, and AGO9) implicated in RNA-directed DNA methylation...

More Information


  1. Pontes O, Li C, Costa Nunes P, Haag J, Ream T, Vitins A, et al. The Arabidopsis chromatin-modifying nuclear siRNA pathway involves a nucleolar RNA processing center. Cell. 2006;126:79-92 pubmed
    ..RNA polymerase IV (Pol IVa and Pol IVb), RNA-DEPENDENT RNA POLYMERASE 2 (RDR2), DICER-LIKE 3 (DCL3), ARGONAUTE4 (AGO4), the chromatin remodeler DRD1, and the de novo cytosine methyltransferase DRM2...
  2. El Shami M, Pontier D, Lahmy S, Braun L, Picart C, Vega D, et al. Reiterated WG/GW motifs form functionally and evolutionarily conserved ARGONAUTE-binding platforms in RNAi-related components. Genes Dev. 2007;21:2539-44 pubmed
    ..Prevailing models imply a distinct function for PolIVb by association of Argonaute4 (AGO4) with the C-terminal domain (CTD) of its largest subunit NRPD1b...
  3. Li C, Pontes O, El Shami M, Henderson I, Bernatavichute Y, Chan S, et al. An ARGONAUTE4-containing nuclear processing center colocalized with Cajal bodies in Arabidopsis thaliana. Cell. 2006;126:93-106 pubmed
    ARGONAUTE4 (AGO4) and RNA polymerase IV (Pol IV) are required for DNA methylation guided by 24 nucleotide small interfering RNAs (siRNAs) in Arabidopsis thaliana...
  4. Gao Z, Liu H, Daxinger L, Pontes O, He X, Qian W, et al. An RNA polymerase II- and AGO4-associated protein acts in RNA-directed DNA methylation. Nature. 2010;465:106-9 pubmed publisher
    ..In plants, 24-nucleotide small interfering RNAs (siRNAs) bound to the effector protein, Argonaute 4 (AGO4), can direct de novo DNA methylation by the methyltransferase DRM2 (refs 2, 4-6)...
  5. Zhong X, Du J, Hale C, Gallego Bartolome J, Feng S, Vashisht A, et al. Molecular mechanism of action of plant DRM de novo DNA methyltransferases. Cell. 2014;157:1050-60 pubmed publisher
    ..We also show that Arabidopsis DRM2 exists in complex with the small interfering RNA (siRNA) effector ARGONAUTE4 (AGO4) and preferentially methylates one DNA strand, likely the strand acting as the template for RNA polymerase V-..
  6. Fagard M, Boutet S, Morel J, Bellini C, Vaucheret H. AGO1, QDE-2, and RDE-1 are related proteins required for post-transcriptional gene silencing in plants, quelling in fungi, and RNA interference in animals. Proc Natl Acad Sci U S A. 2000;97:11650-4 pubmed
    ..These results raise the possibility that PTGS, or at least some of its elements, could participate in the regulation of gene expression during development in plants. ..
  7. Wang H, Zhang X, Liu J, Kiba T, Woo J, Ojo T, et al. Deep sequencing of small RNAs specifically associated with Arabidopsis AGO1 and AGO4 uncovers new AGO functions. Plant J. 2011;67:292-304 pubmed publisher
    ..microRNA (miRNA) and small-interfering RNA (siRNA) pathways for post-transcriptional gene silencing (PTGS), whereas AGO4 regulates transcriptional gene silencing (TGS) via endogenous 24-nucleotide (nt) smRNAs...
  8. Xie M, Ren G, Costa Nunes P, Pontes O, Yu B. A subgroup of SGS3-like proteins act redundantly in RNA-directed DNA methylation. Nucleic Acids Res. 2012;40:4422-31 pubmed publisher
    ..Thus, our results demonstrate that this group of SGS3-like proteins is an important component of RdDM. This study further enhances our understanding of the SGS3 gene family and the RdDM pathway. ..
  9. Raja P, Jackel J, Li S, Heard I, Bisaro D. Arabidopsis double-stranded RNA binding protein DRB3 participates in methylation-mediated defense against geminiviruses. J Virol. 2014;88:2611-22 pubmed publisher
    ..Here, we demonstrate that DRB3 functions with Dicer-like 3 (DCL3) and Argonaute 4 (AGO4) in methylation-mediated antiviral defense...
  10. Parida A, Sharma A, Sharma A. AtMBD6, a methyl CpG binding domain protein, maintains gene silencing in Arabidopsis by interacting with RNA binding proteins. J Biosci. 2017;42:57-68 pubmed
    ..AtMBD6 also interacts with histone deacetylase AtHDA6 that might have a role in chromatin condensation at the targets of RdDM. ..
  11. Zhong X, Hale C, Nguyen M, Ausin I, Groth M, Hetzel J, et al. Domains rearranged methyltransferase3 controls DNA methylation and regulates RNA polymerase V transcript abundance in Arabidopsis. Proc Natl Acad Sci U S A. 2015;112:911-6 pubmed publisher
    ..This work sheds further light on the mechanism by which long noncoding RNAs facilitate RNA-directed DNA methylation. ..
  12. Wu L, Mao L, Qi Y. Roles of dicer-like and argonaute proteins in TAS-derived small interfering RNA-triggered DNA methylation. Plant Physiol. 2012;160:990-9 pubmed publisher
    ..Furthermore, we demonstrated that AGO4/6 complexes rather than AGO1 are responsible for TAS siRNA-guided DNA methylation...
  13. Ye R, Wang W, Iki T, Liu C, Wu Y, Ishikawa M, et al. Cytoplasmic assembly and selective nuclear import of Arabidopsis Argonaute4/siRNA complexes. Mol Cell. 2012;46:859-70 pubmed publisher
    In plants, DNA methylation can be mediated by a class of Argonaute4 (AGO4)-associated heterochromatic siRNAs (hc-siRNAs), through a pathway termed RNA-directed DNA methylation (RdDM)...
  14. Duan C, Zhang H, Tang K, Zhu X, Qian W, Hou Y, et al. Specific but interdependent functions for Arabidopsis AGO4 and AGO6 in RNA-directed DNA methylation. EMBO J. 2015;34:581-92 pubmed publisher
    ..the RNA-directed DNA methylation (RdDM) pathway in Arabidopsis, AGO6 is generally considered to be redundant with AGO4. In this report, our comprehensive, genomewide analyses of AGO4- and AGO6-dependent DNA methylation revealed thatÂ..
  15. Garcia D, Garcia S, Pontier D, Marchais A, Renou J, Lagrange T, et al. Ago hook and RNA helicase motifs underpin dual roles for SDE3 in antiviral defense and silencing of nonconserved intergenic regions. Mol Cell. 2012;48:109-20 pubmed publisher
    ..We identified endogenous SDE3 targets corresponding to nonconserved intergenic regions, transposons and recently evolved pseudogenes, unraveling striking functional convergences among plant and metazoan SDE3 pathways. ..
  16. Brosseau C, Moffett P. Functional and Genetic Analysis Identify a Role for Arabidopsis ARGONAUTE5 in Antiviral RNA Silencing. Plant Cell. 2015;27:1742-54 pubmed publisher
    ..In agreement with functional assays, we show that Potexvirus infection induces AGO5 expression and that both AGO2 and AGO5 are required for full restriction of PVX infection in systemic tissues of Arabidopsis. ..
  17. Oliver C, Santos J, Pradillo M. Accurate Chromosome Segregation at First Meiotic Division Requires AGO4, a Protein Involved in RNA-Dependent DNA Methylation in Arabidopsis thaliana. Genetics. 2016;204:543-553 pubmed
    ..The most relevant results were obtained for ago4-1 In this mutant, meiocytes display a slight reduction in chiasma frequency, alterations in chromatin conformation ..
  18. Lahmy S, Pontier D, Bies Etheve N, Laudié M, Feng S, Jobet E, et al. Evidence for ARGONAUTE4-DNA interactions in RNA-directed DNA methylation in plants. Genes Dev. 2016;30:2565-2570 pubmed publisher
    RNA polymerase V (Pol V) long noncoding RNAs (lncRNAs) have been proposed to guide ARGONAUTE4 (AGO4) to chromatin in RNA-directed DNA methylation (RdDM) in plants...
  19. Rowley M, Avrutsky M, Sifuentes C, Pereira L, Wierzbicki A. Independent chromatin binding of ARGONAUTE4 and SPT5L/KTF1 mediates transcriptional gene silencing. PLoS Genet. 2011;7:e1002120 pubmed publisher
    ..gene silencing pathway where long non-coding RNAs (lncRNAs) produced by RNA Polymerase V (Pol V) guide ARGONAUTE4 (AGO4) to chromatin and attract enzymes that establish repressive chromatin modifications...
  20. Hernández Lagana E, Rodríguez Leal D, Lúa J, Vielle Calzada J. A Multigenic Network of ARGONAUTE4 Clade Members Controls Early Megaspore Formation in Arabidopsis. Genetics. 2016;204:1045-1056 pubmed publisher
    ..Here we show that, in addition to argonaute9 (ago9), mutations in other ARGONAUTE (AGO) genes such as ago4, ago6, and ago8, also show abnormal configurations containing supernumerary gametophytic precursors in Arabidopsis ..
  21. Agorio A, Vera P. ARGONAUTE4 is required for resistance to Pseudomonas syringae in Arabidopsis. Plant Cell. 2007;19:3778-90 pubmed
    Here, we report the characterization of the Arabidopsis thaliana ocp11 (for overexpressor of cationic peroxidase11) mutant, in which a beta-glucuronidase reporter gene under the control of the H(2)O(2)-responsive Ep5C promoter is ..
  22. Zheng Q, Rowley M, Böhmdorfer G, Sandhu D, Gregory B, Wierzbicki A. RNA polymerase V targets transcriptional silencing components to promoters of protein-coding genes. Plant J. 2013;73:179-89 pubmed publisher
    ..A key component of the Arabidopsis RdDM pathway is ARGONAUTE4 (AGO4), which associates with siRNAs to mediate DNA methylation...
  23. Ma X, Nicole M, Meteignier L, Hong N, Wang G, Moffett P. Different roles for RNA silencing and RNA processing components in virus recovery and virus-induced gene silencing in plants. J Exp Bot. 2015;66:919-32 pubmed publisher
    ..Our results demonstrated roles for AGO2 and AGO4 in susceptibility to TRV, whereas VIGS of endogenous genes appeared to be largely mediated by AGO1...
  24. Wang F, Axtell M. AGO4 is specifically required for heterochromatic siRNA accumulation at Pol V-dependent loci in Arabidopsis thaliana. Plant J. 2017;90:37-47 pubmed publisher
    ..The biogenesis of most het-siRNAs depends on the plant-specific RNA polymerase IV (Pol IV), and ARGONAUTE4 (AGO4) is a major het-siRNA effector protein...