Large Neutral Amino Acid Transporter 3 (LAT3)

SLC43A1 belongs to the system L family of plasma membrane carrier proteins that transports large neutral amino acids . The deduced 559-amino acid protein contains 12 transmembrane domains and a leucine zipper motif. A long intracellular loop between transmembrane domains 1 and 2 contains 2 N-glycosylation sites, and 2 other intracellular loops contain putative phosphorylation sites. Northern blot analysis of human tissues detected a 2.5-kb transcript highly expressed in pancreas, liver, skeletal muscle, and fetal liver. Expression was weaker in heart, placenta, lung, kidney, spleen, prostate, testis, ovary, small intestine, colon, lymph node, and bone marrow, and no expression was detected in other tissues examined. Pancreas contained an additional message of 4.4 kb.