Fig. 2: FKBP51 mediates regulatory mechanisms underlying secretory autophagy.

a Quantification of western blot analyses and representative blots of GAL3 and GAL8 normalized to actin from WT cells treated with 100 nM dexamethasone (Dex) or vehicle for 4 h. n = 3 biologically independent samples. Unpaired, one-tailed t-tests were performed; *p < 0.05. Data shown as mean ± s.e.m. b Western blotting of FKBP51, GAL3, GAL8, and HSP90 in FLAG-tagged WT or mutant (TPRmut) FKBP51 co-IP (FLAG-IP) and whole cell extract (WCE) as control performed in cells treated with 100 nM dexamethasone or vehicle. c, d Quantification of GFP⁺ puncta expressed as a percentage of total RFP⁺ puncta in cells (n = 40 cells per group) transfected with tfGal3 construct and treated with 1 mM LLOMe or 300 nM dexamethasone (Dex) for 3 h, followed by 4, 8, and 24 h wash-off, and with co-treatment of bafilomycin (Baf) for 3 h followed by 24 h wash-off. Kruskal–Wallis multiple comparison test was performed; **P < 0.01; ****P < 0.0001. Asterisk symbol indicates comparisons to vehicle; hash symbol indicates comparisons to treatment + Baf. a–d All experiments were performed in SH-SY5Y cells. e, f CTSD from supernatants measured via ELISA after SIM-A9 cells were treated with LLOMe for 4, 8, and 24 h or vehicle for 24 h, or with 3, 30, and 300 nM Dex or vehicle for 4 h. n = 3 per group. Tukey’s multiple comparison test was performed; **P < 0.01; ***P < 0.001; ****P < 0.0001. Only significant comparisons are shown. Data shown as mean ± s.e.m. Fc fold change, Ab antibody.