GSE114214
miR394 and its target gene modulate BR signaling to regulate hypocotyls elongation in Arabidopsis
MicroRNAs and phytophormes are all small molecular signals that play important roles in regulating development and environmental responses in plants. The interplay between them allow the plants to better converge multiple inner and outer signals to optimizing their survival strategy. So far, the knowledge of how miRNAs are involved in brassinosteroid (BR) signaling is lacking. Here, we report the finding of miR394 and its target gene LEAF CURLING RESPONSENESS (LCR), which were transcriptionally responsive to BR, participate in BR signaling in regulating hypocotyls elongation in Arabidopsis. By phenotypic analyzing of a set of transgenic and mutants, miR394 was found to act as a negative regulator in BR signaling in hypocotyls elongation, while its target gene on the contrary. Genetically, miR394 functions upstream of BIN2 and BZR1/BES1, but partially downstream or independent with BRI1 and BSU1. RNA-seq analysis further supports that miR394 inhibits BR signaling through BIN2 because miR394 co-regulate significant number of genes together with BIN2. Additionally, miR394 improved the accumulation of BIN2 but decreased the protein amount of BZR1 and BES1, which can be phosphorylated by BIN2. miR394 also repressed the transcription of PRE1/5/6 and EXP8, the key hypocotyls elongation regulating genes, which had been reported to be BZR1/BES1 targets. These findings revealed a new pathway that miRNA involved in BR signaling in Arabidopsis. Overall design: Col-0, MIR394A OE and bin2-1, 5-day-old light-grown seedlings, 2 replicates for MIR394A OE, 3 replicates for Col-0 and bin2-1