A  Mobile  miR160-Triggered  Transcriptional  Axis  Controls  Root  Stem  Cell  Niche  Maintenance and Regeneration in Arabidopsis
In  multicellular  organisms,  communication  between  cells  is  vital  for  their  fate determination. In plants, the quiescent center (QC) signals to adjacent stem cells to maintain them undifferentiated. However, how surrounding stem cells instruct the QC remains poorly understood. Here we show that in the Arabidopsis root, microRNA160 (miR160)  moves  from  vascular  stem  cells  to  the  QC,  where it degrades the mRNAs of two auxin response factors, ARF10 and ARF17. This degradation relieves BRAVO from direct transcriptional repression, maintaining QC quiescence. We further identify that blocking miR160 movement due to DNA damage-induced vascular stem cell death and restricted symplastic transport reduces BRAVO and WOX5 expression, leading to QC division to replenish damaged stem cells during root regeneration. Together, our results demonstrate that a transcriptional axis initiated by mobile miR160 regulates the QC and stem cell behavior, advancing our understanding of the communication between stem cells and their surrounding cellular environment. Overall design: Comparative gene expression profiling analysis of RNA-seq data for Col-0, arf10-3 arf16-3, 35S:MIR160c anf pARF10:mARF10-GFP; each genotype has three replicates; 12 samples in Total.