Regulation of cationic amino acid transporter (CAT) gene expression.

The Cat family of genes have revealed unexpected complexity and regulation. The first 5 years of research have been productive, yet many important questions remain to be addressed. A major problem for the field of amino acid transport is a severe paucity of data on the structure of these proteins and their arrangement in membranes. There is a need for epitope-specific antisera to distinguish the mCAT2/2A proteins and reagents that will specifically block transport to each of these proteins. The question of gene redundancy will be answered by using genetic approaches such as targeted gene ablation, tissue-specific gene knockout and transgenic overexpression. From this information and more physiological analysis, it will be possible to determine the role and significance of these transport proteins.