RNA-directed DNA methylation and plant development require an IWR1-type transcription factor.
RNA-directed DNA methylation (RdDM) in plants requires two RNA polymerase (Pol) II-related RNA polymerases, namely Pol IV and Pol V. A genetic screen designed to reveal factors that are important for RdDM in a developmental context in Arabidopsis identified DEFECTIVE IN MERISTEM SILENCING 4 (DMS4). Unlike other mutants defective in RdDM, dms4 mutants have a pleiotropic developmental phenotype. The DMS4 protein is similar to yeast IWR1 (interacts with RNA polymerase II), a conserved putative transcription factor that interacts with Pol II subunits. The DMS4 complementary DNA partly complements the K1 killer toxin hypersensitivity of a yeast iwr1 mutant, suggesting some functional conservation. In the transgenic system studied, mutations in DMS4 directly or indirectly affect Pol IV-dependent secondary short interfering RNAs, Pol V-mediated RdDM, Pol V-dependent synthesis of intergenic non-coding RNA and expression of many Pol II-driven genes. These data suggest that DMS4 might be a regulatory factor for several RNA polymerases, thus explaining its diverse roles in the plant.
Kanno
Tatsuo
T
Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, Dr Bohr-Gasse 3, 1030 Vienna, Austria.
Bucher
Etienne
E
Daxinger
Lucia
L
Huettel
Bruno
B
Kreil
David P
DP
Breinig
Frank
F
Lind
Marc
M
Schmitt
Manfred J
MJ
Simon
Stacey A
SA
Gurazada
Sai Guna Ranjan
SG
Meyers
Blake C
BC
Lorkovic
Zdravko J
ZJ
Matzke
Antonius J M
AJ
Matzke
Marjori
M
D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D019175:DNA Methylation / Q000235:genetics / Q000502:physiology*; D018744:DNA, Plant / Q000235:genetics / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology*; D020868:Gene Silencing / Q000502:physiology; D009154:Mutation; D010641:Phenotype; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D022661:RNA, Untranslated / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D029681:Arabidopsis Proteins; C548147:DMS4 protein, Arabidopsis; D018744:DNA, Plant; D018749:RNA, Plant; D034741:RNA, Small Interfering; D022661:RNA, Untranslated; D014157:Transcription Factors; C499181:RNA polymerase IV, Arabidopsis; C538841:RNA polymerase V, Arabidopsis; D012321:DNA-Directed RNA Polymerases