Although the peroxisome proliferator-activated receptor (PPARα) binds and is activated by a
variety of synthetic xenobiotics, the identity of the high affinity endogenous ligand (s) is
incompletely resolved. Likewise, it is not known how putative endogenous ligands alter
PPARα conformation in order to affect transcriptional regulation. Direct fluorescence binding
and fluorescence displacement assays showed for the first time that PPARα exhibits high
affinity (1–14 nm K d values) for unsaturated long chain fatty acyl-CoAs as well as …