MIR166/165 genes exhibit dynamic expression patterns in regulating shoot apical meristem and floral development in Arabidopsis.
The miR166/165 group and its target genes regulate diverse aspects of plant development, including apical and lateral meristem formation, leaf polarity, and vascular development. We demonstrate here that MIR166/165 genes are dynamically controlled in regulating shoot apical meristem (SAM) and floral development in parallel to the WUSCHEL (WUS)-CLAVATA (CLV) pathway. Although miR166 and miR165 cleave same target mRNAs, individual MIR166/165 genes exhibit distinct expression domains in different plant tissues. The MIR166/165 expression is also temporarily regulated. Consistent with the dynamic expression patterns, an array of alterations in SAM activities and floral architectures was observed in the miR166/165-overproducing plants. In addition, when a MIR166a-overexpressing mutant was genetically crossed with mutants defective in the WUS-CLV pathway, the resultant crosses exhibited additive phenotypic effects, suggesting that the miR166/165-mediated signal exerts its role via a distinct signaling pathway.
Jung
Jae-Hoon
JH
Molecular Signaling Laboratory, Department of Chemistry, Seoul National University, Seoul, 151-742, South Korea.
Park
Chung-Mo
CM
D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D035264:Flowers / Q000254:growth & development* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant / Q000235:genetics*; D018519:Meristem / Q000254:growth & development* / Q000378:metabolism; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D018749:RNA, Plant / Q000378:metabolism; D015398:Signal Transduction
D029681:Arabidopsis Proteins; D012333:RNA, Messenger; D018749:RNA, Plant