Nonapoptotic function of Bcl-2 family members as energystat of mitochondrial metabolism. Through multiple interactions with mitochondrial proteins (cyan), antiapoptotic (yellow) as well as proapoptotic (orange) Bcl-2 family members regulate glucose-driven mitochondrial ATP synthesis, thereby acting as energystat. Dark blue arrows depict interactions reported in the literature, while red arrows portray putative interactions that remain to be confirmed. Oxidative phosphorylation complexes are depicted as I, II, III, IV and V. ANT, adenine nucleotide transporter; CC, citrate carrier; CS, citrate synthase; GK, glucokinase; G6P, glucose 6-phosphate; PC, pyruvate carboxylase; PDH, pyruvate dehydrogenase; VDAC, voltage-dependent anion channel.