PUTATIVE MEMBRANE FATTY-ACID TRANSLOCASE AND CYTOPLASMIC FATTY-ACID-BINDING PROTEIN ARE COEXPRESSED IN RAT-HEART AND SKELETAL-MUSCLES

A membrane protein (FAT) homologous to CD36 has recently been implicat ed in the binding end transport of long-chain fatty acids (FA). Expres sion of this protein in rat heart, skeletal muscles and in isolated ca rdiac cells was studied. Changes in expression during development of t he heart were also examined. Expression of FAT was compared to that of the cytoplasmic fatty acid-binding protein (H-FABP) to determine whet her coexpression, indicative of related biological functions, could be demonstrated. FAT and H-FABP mRNAs showed a similar muscle tissue dis tribution and similar cellular localization in the heart. During devel opment, heart mRNA levels for both proteins were upregutated in the sa me way. In conclusion, expression of FAT and H-FABP in muscle tissues and cell-types with high FA metabolism and the upregulation of mRNA le vels associated with heart development, when FA utilization increases, support the suggested role of both proteins in FA metabolism. (C) 199 5 Academic Press, inc.