title: RBE controls microRNA164 expression to effect floral organogenesis.
abstract: The establishment and maintenance of organ boundaries are vital for animal and plant development. In the Arabidopsis flower, three microRNA164 genes (MIR164a, b and c) regulate the expression of CUP-SHAPED COTYLEDON1 (CUC1) and CUC2, which encode key transcriptional regulators involved in organ boundary specification. These three miR164 genes are expressed in distinct spatial and temporal domains that are crucial for their function. Here, we show that the C2H2 zinc finger transcriptional repressor encoded by RABBIT EARS (RBE) regulates the expression of all three miR164 genes. Furthermore, we demonstrate that RBE directly interacts with the promoter of MIR164c and negatively regulates its expression. We also show that the role of RBE in sepal and petal development is mediated in part through the concomitant regulation of the CUC1 and CUC2 gene products. These results indicate that one role of RBE is to fine-tune miR164 expression to regulate the CUC1 and CUC2 effector genes, which, in turn, regulate developmental events required for sepal and petal organogenesis.
authors.affiliation: Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06520-8104, USA.
authors.forename: Tengbo
authors.initials: T
authors.lastname: Huang
authors.forename: Francesc
authors.initials: F
authors.lastname: López-Giráldez
authors.forename: Jeffrey P
authors.initials: JP
authors.lastname: Townsend
authors.forename: Vivian F
authors.initials: VF
authors.lastname: Irish
mesh_terms: D017360:Arabidopsis / Q000166:cytology / Q000196:embryology* / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D035264:Flowers / Q000166:cytology / Q000196:embryology* / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant / Q000235:genetics; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D009928:Organ Specificity / Q000235:genetics; D038081:Organogenesis / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding / Q000235:genetics; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D013997:Time Factors
chemical_list: D029681:Arabidopsis Proteins; C426007:CUC1 protein, Arabidopsis; C107294:CUC2 protein, Arabidopsis; C538852:MIRN164 microRNA, Arabidopsis; D035683:MicroRNAs; C509081:RBE protein, Arabidopsis; D012097:Repressor Proteins