Fig 1: Down-regulation of BACE1 protein in aged Mgat3−/− mouse brain Immunostaining of 12-month-old brain sections (cerebral cortex) with anti-BACE1. Scale bar, 100 μm. Proteins from the membrane fractions of 12-month-old mouse brains (n = 4–5) were immunoblotted for BACE1, and BACE1 intensity was quantified. *P = 0.044. Lysates from MEFs were immunoblotted for APP, BACE1, or GAPDH (loading control), and BACE1 intensity was quantified (n = 4). Amount of Aβ40 in the culture medium of immortalized MEFs (n = 3). *P = 0.045. MEFs were transfected with control siRNA or GGA3-siRNA and then immunoblotted for BACE1, GGA3, or GAPDH (loading control) (n = 6). Data Information: All graphs show means ± SEM (*P < 0.05; Student's t-test for (B) and the Mann–Whitney U-test for (D)).Source data are available online for this figure.