title: The role of decapping proteins in the miRNA accumulation in Arabidopsis thaliana.
abstract: Decapping 1 (DCP1), Decapping 2 (DCP2) and VARICOSE (VCS) are components of the decapping complex that removes the 7-methyl-guanosine 5'-diphosphate from the 5' end of mRNAs. In animals, the decapping proteins are involved in miRNA-mediated gene silencing, whereas in plants the roles of the decapping proteins in the miRNA pathway are not well understood. Here we demonstrated that the accumulation of miRNAs decreased in dcp1, dcp2 and vcs mutants, indicating that DCP1, DCP2 and VCS are important for the miRNA pathway in Arabidopsis thaliana. The primary miRNAs (pri-miRNAs) did not increase and miRNA biogenesis components did not decrease in these mutants, suggesting that the miRNA decrease in decapping mutants is not due to the defect of pri-miRNA processing. We showed that the accumulation of miRNA targets increased concomitantly with the decrease of miRNA in the decapping mutants. Our results suggested that the seedling lethal phenotypes in the dcp1, dcp2 and vcs mutants are caused not only by the defect in decapping, but also by the disruption of miRNA-mediated gene regulation.
authors.affiliation: Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Motomura
authors.forename: Quy Tn
authors.initials: QT
authors.lastname: Le
authors.forename: Naoyoshi
authors.initials: N
authors.lastname: Kumakura
authors.forename: Takashi
authors.initials: T
authors.lastname: Fukaya
authors.forename: Atsushi
authors.initials: A
authors.lastname: Takeda
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Watanabe
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D056970:Co-Repressor Proteins / Q000235:genetics / Q000378:metabolism; D004722:Endoribonucleases / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D018506:Gene Expression Regulation, Plant; D005816:Genetic Complementation Test; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D012323:RNA Processing, Post-Transcriptional; D018749:RNA, Plant / Q000378:metabolism*; D036226:Seedlings / Q000235:genetics / Q000254:growth & development / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D056970:Co-Repressor Proteins; C572638:DCP5 protein, Arabidopsis; D035683:MicroRNAs; D018749:RNA, Plant; C483689:VARICOSE protein, Arabidopsis; D004722:Endoribonucleases; C518493:Dcp1 protein, Arabidopsis; C518494:Dcp2 protein, Arabidopsis