Peroxisomal Trans-2-Enoyl Coenzyme A Reductase (PECR)

Chain elongation of fatty acids occurs in endoplasmic reticulum (ER) and mitochondria and is thought to occur in peroxisomes. Like the mitochondrial system, the proposed peroxisomal system requires a 2-enoyl-CoA reductase for the last step of elongation. PECR was found to catalyze the reduction of trans-2-enoyl-CoAs of varying chain lengths. The deduced human protein contains 303 amino acids, including a C-terminal type I peroxisomal targeting signal, and has a predicted molecular mass of 33 kD. The guinea pig, mouse, and human proteins share 71 to 75% amino acid identity. Northern blot analysis of mouse tissues detected a 1.3-kb transcript expressed at high levels in liver and kidney, with lower levels in heart, skeletal muscle, and other tissues.