Sterol carrier protein-2

The compartmentalization of cholesterol metabolism implies target-specific cholesteroI trafficking between the endoplasmic reticulum, plasma membrane, lysosomes, mitochondria and peroxisomes. One hypothesis has been that ster ol carrier protein-2 (SCP2, also known as the non-specific lipid transfer p rotein) acts in cholesterol transport through the cytoplasm. Recent studies employing gene targeting in mice showed, however, that mice lacking SCP2 a nd the related putative sterol carrier known as SCPx, develop a defect in p eroxisomal P-oxidation. In addition, diminished peroxisomal a-oxidation of phytanic acid (3,7,11,15-tetramethylhexadecanoic acid) in these null mice w as attributed to the absence of SCP2 which has a number of properties suppo rting a function as carrier for fatty acyl-CoAs rather than for sterols. (C ) 2000 Elsevier Science B.V. All rights reserved.