A role for the peroxisomal 3-ketoacyl-CoA thiolase B enzyme in the control of PPARα-mediated upregulation of SREBP-2 target genes in the liver

► Lack of peroxisomal 3-ketoacyl-CoA thiolase B is associated with decreased peroxisomal β-oxidation of palmitate under conditions of metabolic stress (Wy14,643) in mice. ► Absence of 3-ketoacyl-CoA thiolase B does not impact on liver cell and peroxisome proliferation. ► Ablation of 3-ketoacyl-CoA thiolase B does not modulate the PPARalpha signaling pathway; yet, deletion of 3-ketoacyl-CoA thiolase B impacts on the activation of a large set of SREBP-2 target genes by the potent PPARalpha agonist Wy14,643 in the liver. ► Peroxisomal 3-ketoacyl-CoA thiolase B, a new actor in cholesterol metabolism located at the cross road of the SREBP-2 and PPARalpha signaling pathways?