Regulation of Flowering Time and Floral Organ Identity by a MicroRNA and Its APETALA2-Like Target Genes

摘要: MicroRNAs (miRNAs) are ∼21-nucleotide noncoding RNAs that have been identified in both animals and plants. Although there is direct evidence implicating particular miRNAs the control of developmental timing, to date it not known whether plant also play a role regulating temporal transitions. Through an activation-tagging approach, we demonstrate miRNA 172 (miR172) causes early flowering disrupts specification floral organ identity when overexpressed Arabidopsis. miR172 normally expressed manner, consistent with its proposed time control. The regulatory target subfamily APETALA2 (AP2) transcription factor genes. We present downregulates these genes by translational mechanism rather than RNA cleavage. Gain-of-function loss-of-function analyses indicate two AP2-like act as repressors, supporting notion regulates downregulating