Fatty Acid Transport Protein 1 (FATP1)

Transfected cells were grown in the presence of a fluorescent fatty acid analog and those that became positive for the dye were sorted and the cDNA recovered. Two classes of clones were identified: one encodes a 699-amino acid protein resembling rat liver fatty acyl CoA synthetase (FACL2), and the second encodes a 646-amino acid protein with 6 potential transmembrane domains. Northern blot analysis showed high levels of FATP in 3T3-L1 adipocytes, with a major 2.9-kb transcript and a minor 3.8-kb form. Expression increased 5-fold during differentiation of preadipocytes to adipocytes. In normal mouse tissues, FATP mRNA levels were highest in skeletal muscle, heart, and fat. Expression studies showed that FATP increased the uptake of labeled oleic acid by 3- to 4-fold, and similar effects were observed with other LCFAs.