Knockdown of VAMP8 or Stx1B decreases the localization of N-cadherin at the PM in cultured RGCs and COS7 cells. (A) N-cadherin (Ncad; green) and VAMP8 (red) stained with DAPI (blue) in the control (siLuciferase) and VAMP8-depleted RGCs. Scale bar, 10 µm. (B) N-cadherin ectodomain stained in the control and VAMP8-depleted RGCs. Scale bar, 10 µm. (C) N-cadherin (green) and Stx1B (red) stained with DAPI (blue) in the control and Stx1B-depleted RGCs. Scale bar, 10 µm. (D) N-cadherin ectodomain stained in the control and Stx1B-depleted RGCs. Scale bar, 10 µm. (E–G) Immunoblots showing the levels of total and cell surface N-cadherin in control and VAMP8- (E) or Stx1B-depleted (F) RGCs. Relative levels of N-cadherin were calculated from three independent experiments. (H) Immunoblots showing N-cadherin and E-cadherin in the WT RGCs, COS7 cells, and mouse small intestines. GAPDH blotting was used as a loading control. (I–K) Ncad and SNAP23 (I), VAMP8 (J), or Stx1B (K) stained in the control and SNAP23-, VAMP8-, or Stx1B-depleted COS7 cells. Scale bars, 10 µm. The bar graphs represent the means ± SEM. Significance was calculated using two-tailed paired Student’s t tests. Statistical significance is indicated by *P < 0.05 or **P < 0.01.