Small RNA-seq analysis reveals that miR-182 is the most abundant miRNA in RGC axons miR-182 regulates Slit2-mediated axon guidance of RGCs in vitro and in vivo miR-182 silences cofilin-1 local protein synthesis in growth cones Slit2 rapidly lifts miR-182-mediated repression of cofilin-1 without degrading it