Fig. 4

Reduced sorting nexin-4 (SNX4) levels decrease β-site amyloid precursor protein-cleaving enzyme 1 (BACE1) and β-amyloid (Aβ). a SH-SY5Y cells were cotransfected with BACE1 and either SNX4 small interfering RNA (siRNA) or control siRNA (siCTL). Quantitative Western blot analysis using anti-BACE1, anti-Aβ (6E10), anti-β-actin, anti-amyloid precursor protein (anti-APP), anti-soluble ectodomain-secreted β-amyloid precursor protein derivative (anti-sAPPβ), and anti-SNX4 antibodies was performed, and the amounts of Aβ and sAPPβ in the culture medium were analyzed by immunoblotting. b Quantification of Western blot band intensities. The graphs display the immunoreactivity to BACE1, APP, sAPPβ, and Aβ antibodies, normalized to β-actin. **p < 0.01, ***p < 0.001. c SH-SY5Y cells were transfected with either siCTL or siSNX4. Immunocytochemistry was performed using an anti-hemagglutinin (anti-HA) antibody (green). Scale bar = 20 μm. d Primary mouse cortical neurons were cotransfected with BACE1 and either shCTL or shSNX4. Western blot analysis was performed using anti-BACE1, anti-APP, anti-sAPPβ, anti-β-actin, anti-Aβ (6E10), and anti-SNX4 antibodies. The amounts of Aβ and sAPPβ were analyzed in the culture medium by immunoblotting. e Quantification of Western blot band intensities. The graphs display the immunoreactivity to anti-BACE1, anti-APP, anti-sAPPβ, and anti-Aβ antibodies, normalized to β-actin. **p < 0.01, ***p < 0.001. f Primary neurons were cotransfected with BACE1-HA and either shCTL or shSNX4. Immunocytochemistry was performed using an anti-HA antibody (green). Scale bar = 20 μm