Role of CD36 in membrane transport and utilization of long-chain fatty acids by different tissues

The transmembrane glycoprotein CD36 has been identified in isolated cell st udies as a putative transporter of long-chain fatty acids. To examine the p hysiological role of CD36, we studied FA uptake and metabolism by tissues o f CD36 null mice after injection with two fatty acid analogs. Compared to c ontrols, uptake was substantially reduced (50-80%) in heart, skeletal muscl e, and adipose tissues of null mice. The reduction in uptake was associated with a large decrease in fatty acid incorporation into triglycerides, whic h could be accounted for by an accumulation of diacylglycerides. Thus CD36 facilitates a major fraction of fatty acid uptake by myocardial, skeletal m uscle, and adipose tissues, where it is highly expressed. Its role in other tissues where its expression is low and cell-specific could not be determi ned in these studies.