In vivo investigation of the transcription, processing, endonucleolytic activity, and functional relevance of the spatial distribution of a plant miRNA.
We show, with miR171, that plant miRNA genes are modular independent transcription units in which the fold-back pre-miRNA is sufficient for miRNA processing, and that the upstream region contains highly specific promoter elements. Processing depends on flanking sequences within the miRNA stem-loop precursor rather than the miRNA sequence itself, and mutations affecting target pairing at the center and 5' but not 3' region of the miRNA compromise its function in vivo. Inactivation of the SDE1 RNA-dependent-RNA-polymerase was mandatory for accurate representation of miRNA activity by sensor constructs in Arabidopsis. Work in sde1 background revealed a near-perfect spatial overlap between the patterns of miR171 transcription and activity, supporting the idea that plant miRNAs enable cell differentiation.
Parizotto
Eneida Abreu
EA
Institut de Biologie Moléculaire des Plantes du CNRS, 67084 Strasbourg Cedex, France.
Dunoyer
Patrice
P
Rahm
Nadia
N
Himber
Christophe
C
Voinnet
Olivier
O
D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D035683:MicroRNAs / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D009690:Nucleic Acid Conformation; D030821:Plants, Genetically Modified; D034622:RNA Interference; D012323:RNA Processing, Post-Transcriptional; D018749:RNA, Plant / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012324:RNA-Dependent RNA Polymerase / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic
D029681:Arabidopsis Proteins; D008164:Luminescent Proteins; D035683:MicroRNAs; D018749:RNA, Plant; D049452:Green Fluorescent Proteins; D012324:RNA-Dependent RNA Polymerase; C492661:SDE1 protein, Arabidopsis