N-terminal domain of SNX1 is required for the normal trafficking of mGluR1. A, B, Western blot (A) and quantitation of the Western blots (B), showing the effective knockdown of endogenous SNX1 by shSNX1 and expression of the SNX1ΔN replacement construct. C, D, Representative images (C) and quantitation (D) showing that expression of shSNX1 and shSNX1:SNX1ΔN had no effect on the surface expression of myc-mGluR1. E, F, Representative cells (E) and quantitation (F) of 100 μm R,S-DHPG-induced trafficking of myc-mGluR1 suggested that, knockdown of endogenous SNX1 led to the rapid recycling of myc-mGluR1 in 30 min post-ligand application, and expression of SNX1ΔN replacement construct did not rescue the normal trafficking of the receptor. Results are presented as mean ± SEM collected from three independent experiments. Scale bar, 10 μm. ***p < 0.001, * p < 0.05; n.s., p > 0.05.