Fig. 1: Rapid increase in lysosomes in mouse cerebrocortical cultures upon EGF treatment.

A Microscopic images (left) and a quantitative graph (right) depict the time-dependent elevation in lysotracker red (LTR) fluorescence following treatment with 100 ng/ml recombinant mouse EGF. Scale bar: 20 µm. The line graph represents LTR intensity measured using the Image J program (mean ± SEM, n = 32 different fields taken from ≥4 independent biological replicate experiments). *p < 0.05; compared with 0-h time point using ANOVA with Dunnett’s post-hoc test. B Western blot analysis (left) and quantitative graph (right) show changes in the protein levels of EGF receptor (EGFR) and lysosomal associated membrane protein-1 (LAMP-1) over time after EGF treatment. Actin was used as the loading control. The line graph depicts the band density ratio of total LAMP-1 to Actin (closed circle) and EGFR to Actin (open circle) over time (mean ± SEM, n = 3 independent biological replicate experiments, *p < 0.05, **p < 0.01, ***p < 0.001, or ****p < 0.0001; compared with the 0-hour time point using ANOVA with Dunnett’s post-hoc test). C Western blot analysis (left) and quantitative graph (right) display the protein levels of CTSB over time after EGF treatment. The line graph depicts the band density ratio of pro-form (closed circle) or mature form of CTSB (open circle) to Actin over time (mean ± SEM, n = 6 independent biological replicate experiments). D Microscopic images (left) and a quantitative graph (right) reveal the time-dependent increase in in situ CTSB activity following treatment with 100 ng/ml EGF. Scale bar: 20 µm. The line graph represents CTSB activity determined using the Image J program (mean ± SEM, n = 34 different fields taken from ≥4 independent biological replicate experiments, *p < 0.05 **p < 0.01, ***p < 0.001, or ****p < 0.0001; compared with 0-hour time point using ANOVA with Dunnett’s post-hoc test).