Solution structure of the satiety factor, CART, reveals new functionality of a well-known fold

Cocaine and amphetamine regulated transcript (CART) peptide has been shown to be an anorectic peptide that inhibits both normal and starvation-induced feeding and completely blocks the feeding response induced by neuropeptide Y and regulated by leptin in the hypothalamus. The C-terminal part contain ing the three disulfide bridges CART(48-89) is the biologically active part of the molecule affecting food intake. The solution structure of the activ e part of CART has a fold equivalent to other functionally distinct small p roteins. CART consists mainly of turns and loops spanned by a compact frame work composed by a few small stretches of antiparallel beta -sheet common t o cystine knots.