The fine-tuning of TRAF2-GSTP1-1 interaction: effect of ligand binding and in situ detection of the complex.

ABSTRACT: We provide the first biochemical evidence of a direct interaction between the glutathione transferase P1-1 (GSTP1-1) and the TRAF domain of TNF receptor-associated factor 2 (TRAF2), and describe how ligand binding modulates such an equilibrium. The dissociation constant of the heterocomplex is K(d)=0.3 μM; however the binding affinity strongly decreases when the active site of GSTP1-1 is occupied by the substrate GSH (K(d)≥2.6 μM) or is inactivated by oxidation (Kd=1.7 μM). This indicates that GSTP1-1's TRAF2-binding region involves the GSH-binding site. The GSTP1-1 inhibitor NBDHEX further decreases the complex's binding affinity, as compared with when GSH is the only ligand; this suggests that the hydrophobic portion of the GSTP1-1 active site also contributes to the interaction. We ther

SUBMITTER: De Luca A 

PROVIDER: S-EPMC4040697 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature