Rab7a and Rab27b control secretion of endothelial microRNA through extracellular vesicles.

By transporting regulatory RNAs like microRNAs, extracellular vesicles provide a novel layer of intercellular gene regulation. However, the underlying secretory pathways and the mechanisms of cargo selection are poorly understood. Rab GTPases are central coordinators of membrane trafficking with distinct members of this family being responsible for specific transport pathways. Here we identified a vesicular export mechanism for miR-143, induced by the shear stress responsive transcription factor KLF2, and demonstrate its dependency on Rab7a/Rab27b in endothelial cells.