Figure 4. Overexpressed BAG5 may result in loss of its function to promote HSP70 activity. (A–C) U2OS, HeLa, and SH-SY5Y cells were transfected with various amounts of a BAG5-expressing plasmid (pCMV-Tag2B-BAG5). Expression levels of BAG5 were detected by Western blotting. β-Actin served as an internal control. (D–E) Recombinant GST fusion BAG5 and BAG5 (DARA) protein were purified and stained with Coomassie blue. The HSP70-mediated refolding activity was examined with denatured firefly luciferase in the presence of different concentrations of BAG5 (Student’s t-test; *, p < 0.05, **, p < 0.01).