Figure 4From: 14-3-3 zeta is a molecular target in guggulsterone induced apoptosis in Head and Neck cancer cells (A) GS induces dephosphorylation of pBAD. Whole cell lysates obtained from GS (50 μM) treated SCC4 cells were subjected to western blotting using specific antibodies for pBad, total Bad and α-tubulin. Panel shows the dephosphorylation of Bad in time-dependent manner (0 h - 12 h) while no difference was observed in the expression of total Bad protein in GS-treated SCC4 cells. α-tubulin served as loading control. (B) GS induces dissociation of Bad from 14-3-3ζ in head and neck cancer cells. Co-IP assays using specific antibodies were carried out and analyzed by western blotting as described in Materials and Methods. Treatment with GS induced dissociation of Bad from 14-3-3ζ as shown in panel (i) and (ii); association of Bad with Bcl2 as shown in panel (iii) and (iv); association of Bad with Bcl-xL (v) and (vi); and dissociation of pro-apoptotic protein Bax from Bcl-xL (vii and viii) as well as Bcl2 (ix and x) (C) Okadaic acid (OA) inhibits GS-induced dephosphorylation of Bad. Panel shows inhibition of dephosphorylation of Bad (Ser-136) and its dissociation from 14-3-3ζ in a time-dependent manner as determined using co-IP assays followed by western blotting.Back to article page