Figure 4
From: TCTP contains a BH3-like domain, which instead of inhibiting, activates Bcl-xL
Molecular/functional analysis of the h1 (P1) subregion of BH3-TCTP.
(A) The three BH3 peptides (TCTP in blue, Bax in red and the hybrid Bax/TCTP aligned with the h1 subregion framed). (B) Interaction between Bcl-xL and TCTP-BH3, or Bax or hybrid Bax/TCTP peptides. Calorimetric titration between Bcl-xL (0.043 mM) and increasing amount of TCTP-BH3 (0.75 mM) (blue curve); Bcl-xL (0.006 mM) and increasing amount of Bax (0.117 mM) (red curve); Bcl-xL (0.043 mM) and increasing amount of hybrid Bax/TCTP (0.65 mM) (black curve); Each experiment was carried at 30 °C in 50 mM ammonium bicarbonate pH 9. (C) Thymocytes from TCTP+/− mice were γ-irradiated (γ-irr) (2.5 Gy) and cultured in the presence of WT TCTP1–31 peptide, hybrid Bax/TCTP peptide at the indicated concentrations ranging from 0 to 1000 nM. (D) Schematic representation of the TCTP/Bcl-xL interaction in the context of the reciprocal feedback loop between P53 and TCTP, sequestering of P53 by Bcl-xL and the control of Bax.
