Regulatory role of E-NTPase/NTPDase in fat/CD36-mediated fatty acid uptake


Present address: Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA. Tel./fax: +1-409-750-9060


Fatty acid translocase (FAT)/CD36-mediated long-chain fatty acid uptake in human umbilical vessel endothelial cells is associated with as yet uncharacterized translocase activity. The molecular mechanism of its function is not yet understood. Numerous attempts to purify rat cardiac sarcolemmal E-NTPase (an integral membrane protein also referred to as ecto-Ca2+/Mg2+ATPase) have revealed a complete amino acid sequence identity for FAT/CD36 protein. The most striking observation is that purified CD36 from human platelets shows significant E-NTPase activity. In view of recent progress in understanding CD36 functional properties, an attempt is made in this article to illustrate the point that association of E-NTPase (possibly extracellular Ca2+/Mg2+nucleotide triphosphate diphosphohydrolase) activity with CD36 may be of potential functional significance.