Fig. 2: TRAF2/3 double deficiency reduces caspase activation and promotes transcription of IAPs that protect B-TRAF2/3-DKO B cells from DNA damage-induced apoptosis.

A Representative data of proteome profiler mouse apoptosis array of LMC or dKO (B-TRAF2/3-DKO) B cells cultured for 16 h in the presence of Ara-C (10 μg/ml). Red line: active caspase3; green line: XIAP. All abbreviations are applied to other panels. B Quantification of dot density of active caspase 3 and XIAP presented in panel A. C Representative data of western blotting of LMC or DKO B cells treated by Ara-C for 16 h. Casp-3: caspase 3, Casp-9: caspase 9. AKT as protein loading control. Quantification of the band intensity for active Caspase 9 in LMC or DKO B cells (n = 2). D Quantification of real-time PCR data from triplicates of one representative experiment using LMC or dKO B cells treated by Ara-C for 16 h. Statistical analysis was performed using unpaired student’s t test for panel B and D. E, F Quantification of the percentage of alive cells upon IAP antagonist treatment. LMC or dKO B cells were pretreated with indicated concentration of a pan IAP inhibitor, AZD5582 (AZD) (E) or a XIAP selective inhibitor, SM-164 (SM) (F), then cultured in the presence of Ara-C for 16 h. For panel E and F, cells were stained by Aqua and Annexin-V for flow cytometry analysis. Quantification of alive cells are shown from duplicates of one experiment of flow data. Statistical analysis was performed using two-way ANOVA for panel E and F. Significant difference was observed between LMC and dKO for all concentration (0 to 5 μM) except 10 μM for panel E, and for all concentration (0 to 10 μM) for panel F. NS no significance (p > 0.05); *p < 0.05, ***p < 0.001. All experiments were independently repeated 2 to 5 times.