title: The PRP6-like splicing factor STA1 is involved in RNA-directed DNA methylation by facilitating the production of Pol V-dependent scaffold RNAs.
abstract: DNA methylation is a conserved epigenetic marker in plants and animals. In Arabidopsis, DNA methylation can be established through an RNA-directed DNA methylation (RdDM) pathway. By screening for suppressors of ros1, we identified STA1, a PRP6-like splicing factor, as a new RdDM regulator. Whole-genome bisulfite sequencing suggested that STA1 and the RdDM pathway share a large number of common targets in the Arabidopsis genome. Small RNA deep sequencing demonstrated that STA1 is predominantly involved in the accumulation of the siRNAs that depend on both Pol IV and Pol V. Moreover, the sta1 mutation partially reduces the levels of Pol V-dependent RNA transcripts. Immunolocalization assay indicated that STA1 signals are exclusively present in the Cajal body and overlap with AGO4 in most nuclei. STA1 signals are also partially overlap with NRPE1. Localization of STA1 to AGO4 and NRPE1 signals is probably related to the function of STA1 in the RdDM pathway. Based on these results, we propose that STA1 acts downstream of siRNA biogenesis and facilitates the production of Pol V-dependent RNA transcripts in the RdDM pathway.
authors.affiliation: National Institute of Biological Sciences, Beijing 102206, China, College of Life Science, Beijing Normal University, Beijing 100875, China, Shanghai Center for Plant Stress Biology and Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China and Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Kun
authors.initials: K
authors.lastname: Dou
authors.forename: Chao-Feng
authors.initials: CF
authors.lastname: Huang
authors.forename: Ze-Yang
authors.initials: ZY
authors.lastname: Ma
authors.forename: Cui-Jun
authors.initials: CJ
authors.lastname: Zhang
authors.forename: Jin-Xing
authors.initials: JX
authors.lastname: Zhou
authors.forename: Huan-Wei
authors.initials: HW
authors.lastname: Huang
authors.forename: Tao
authors.initials: T
authors.lastname: Cai
authors.forename: Kai
authors.initials: K
authors.lastname: Tang
authors.forename: Jian-Kang
authors.initials: JK
authors.lastname: Zhu
authors.forename: Xin-Jian
authors.initials: XJ
authors.lastname: He
mesh_terms: D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D060565:Argonaute Proteins / Q000032:analysis; D020541:Coiled Bodies / Q000737:chemistry / Q000201:enzymology; D019175:DNA Methylation; D012321:DNA-Directed RNA Polymerases / Q000032:analysis / Q000378:metabolism*; D020868:Gene Silencing; D018745:Genome, Plant; D009154:Mutation; D009687:Nuclear Proteins / Q000032:analysis / Q000235:genetics / Q000502:physiology*; D034741:RNA, Small Interfering / Q000096:biosynthesis*; D058727:RNA, Small Untranslated / Q000096:biosynthesis
chemical_list: C471209:AGO4 protein, Arabidopsis; D029681:Arabidopsis Proteins; D060565:Argonaute Proteins; D009687:Nuclear Proteins; D034741:RNA, Small Interfering; D058727:RNA, Small Untranslated; C471271:ROS1 protein, Arabidopsis; C519660:STA1 protein, Arabidopsis; C499181:RNA polymerase IV, Arabidopsis; C538841:RNA polymerase V, Arabidopsis; D012321:DNA-Directed RNA Polymerases