The receptor-like kinases BAM1 and BAM2 promote the cell-to-cell movement of miRNA in the root stele to regulate xylem patterning

ABSTRACT Xylem patterning in the root is established through the creation of opposing gradients of miRNAs and their targets, enabled by the cell-to-cell spread of the former. The miRNAs involved in xylem patterning, miR165/6, move through plasmodesmata, but how their trafficking is regulated remains elusive. Here, we describe that the receptor-like kinases BAM1/2 are required for the intercellular movement of miR165/6 in the stele and hence proper xylem patterning in the root.