Sterol Carrier Protein 2 Like Protein (SCP2L)

MFE2, also called multifunctional protein 2 or D-bifunctional protein, is a 79-kDa enzyme which possesses a typical peroxisomal matrix protein targeting signal (COOH-terminal Ala-Lys-Leu). MFE2 consists of a 3R-hydroxyacyl-CoA dehydrogenase (HD) domain, a 2E-enoyl-CoA hydratase 2 (H2) domain, and a sterol carrier protein 2-like (SCP2L) domain, and is known to catalyze the second and third steps of the peroxisomal β-oxidation of fatty acids and their derivatives. SCP2 encodes two proteins: sterol carrier protein X (SCPx) and sterol carrier protein 2 (SCP2), as a result of transcription initiation from 2 independently regulated promoters. Evidence suggests that the SCPx protein is a peroxisome-associated thiolase that is involved in the oxidation of branched chain fatty acids, while the SCP2 protein is thought to be an intracellular lipid transfer protein.