Pumilio 2 (PUM2) is a member of the Puf family of mRNA binding proteins and translational regulators which are involved in various processes including embryonic patterning and memory formation. Nevertheless, its functions in the outgrowth of neuronal axons have not been studied. This study shows endogenous expression of PUM2 in neurites of dorsal root ganglia (DRG) neurons and transport of PUM2 along retinal ganglion cell (RGC) axons and their growth cones. Overexpression of PUM2 in DRG neurons resulted in shorter axons when compared to control neurons. Expression of either dominant negative mutation (dnPUM2) or PUM2W349G displayed a reduction in axonal length. PUM2 downregulation with microRNA (miRNA) also caused a reduction in neurite length compared to control neurons. Finally, PUM2 silencing did not alter eye size at E4, which allows investigation of axonal outgrowth in RGC in vivo. These results suggest a novel role for PUM2 in axonal outgrowth.

Pumilio 2 (PUM2) is a member of the Puf family of mRNA binding proteins and translational regulators which are involved in various processes including embryonic patterning and memory formation. Nevertheless, its functions in the outgrowth of neuronal axons have not been studied. This study shows endogenous expression of PUM2 in neurites of dorsal root ganglia (DRG) neurons and transport of PUM2 along retinal ganglion cell (RGC) axons and their growth cones. Overexpression of PUM2 in DRG neurons resulted in shorter axons when compared to control neurons. Expression of either dominant negative mutation (dnPUM2) or PUM2W349G displayed a reduction in axonal length. PUM2 downregulation with microRNA (miRNA) also caused a reduction in neurite length compared to control neurons. Finally, PUM2 silencing did not alter eye size at E4, which allows investigation of axonal outgrowth in RGC in vivo. These results suggest a novel role for PUM2 in axonal outgrowth.