Ing experiments. Abbreviations 5-aza-2-dC: 5-aza-2-deoxycytidine; bp: base pair; DHF: dihydrofolate; DHFR: dihydrofolate reductase; DMSO: Dimethyl sulfoxide; GTP: guanosine triphosphate; miRNA: microRNA; MTX: methotrexate (also known as amethopterin); nt: nucleotide; PCR: polymerase chain reaction; RdDM: RNA-directed DNA methylation; RT-PCR: reverse transcription-PCR; SAH: S-adenosylhomocysteine; SAM: S-adenosyl methionine; siRNA: tiny interfering RNA; ssRNA: single-stranded RNA; TAIL-PCR: thermal asymmetric interlaced PCR; TGS: transcriptional gene silencing; THF: tetrahydrofolate. Competing interests The authors declare that they’ve no competing interests. Authors’ contributions TTD and XC wrote the manuscript. TTD designed the chemical screen and performed genetic analyses of LUCL, Southern blot analyses, bisulfite sequencing analyses, luciferase imaging, RT-PCR and McrBC evaluation. TTD and MOL performed the chemical screen. MOL performed the luciferase imaging for the MTX-treated seedlings. SYW did the 5-aza-2-dC therapy and RT-PCR of treated seedlings. XL, TTD and LA generated the LUCL met1-3, LUCL ago4-6 and LUCL drm2-6 genotypes and analyzed them. SL performed the McrBC evaluation on LUCH and LUCL. AD and SRC provided chemical substances, performed compact molecule perturbations and offered intellectual help with regards for the chemical screen. BZ transformed LUCL into rdr6-11. XC constructed the reporter plasmid, conceived and guided the project. All authors read and approved the final manuscript. Acknowledgments The perform was supported by a grant in the National Science Foundation (MCB-1021465) and by Howard Hughes Medical Institute and Gordon and Betty Moore Foundation (by means of Grant GBMF3046) to XC. TTD was supported by a National Science Foundation ChemGen IGERT program (DGE0504249). Author specifics 1 Division of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, CA 92521, USA.N3-PEG4-C2-Pfp ester web 2NSF ChemGen IGERT plan, University of California, Riverside, CA 92521, USA.4-Chloro-6-fluoropyrido[3,4-d]pyrimidine Chemscene 3Howard Hughes Medical Institute, University of California, Riverside, CA 92521, USA.PMID:33645457 four Division of Plant Pathology, University of California, Davis, CA 95616, USA. 5State Important Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200433, China. Received: six November 2012 Accepted: 20 March 2013 Published: five AprilReferences 1. Law JA, Jacobsen SE: Establishing, maintaining and modifying DNA methylation patterns in plants and animals. Nat Rev Genet 2010, 11(3):204?20. two. Aufsatz W, et al: The function of MET1 in RNA-directed de novo and maintenance methylation of CG dinucleotides. Plant Mol Biol 2004, 54(six):793?04. three. Schermelleh L, et al: Dynamics of Dnmt1 interaction with the replication machinery and its role in postreplicative upkeep of DNA methylation. Nucleic Acids Res 2007, 35(13):4301?312. four. Bostick M: UHRF1 plays a part in keeping DNA methylation in mammalian cells. Science 2007, 317:1760?764. five. Arita K, et al: Recognition of hemi-methylated DNA by the SRA protein UHRF1 by a base-flipping mechanism. Nature 2008, 455:818?21. 6. Qian C, et al: Structure and hemimethylated CpG binding from the SRA domain from human UHRF1. J Biol Chem 2008, 283(50):34490?4494. 7. Avvakumov GV, et al: Structural basis for recognition of hemi-methylated DNA by the SRA domain of human UHRF1. Nature 2008, 455(7214):822?25. eight. Chuang LS, et al: Human DNA-(cytosine-5) meth.