Raptin (human, recombinant)

Raptin is a sleep-inducible hormone and C-terminal fragment of reticulocalbin-2 (RCN2) with roles in food intake and obesity prevention in animal models. RCN2 is predominantly expressed by neurons in the paraventricular nucleus (PVN) of the hypothalamus, and this expression is increased during the sleep phase compared to the active phase in mice. During the sleep period, activation of suprachiasmatic nucleus arginine vasopressin neurons (SCNAVPs) induces kallikrein-mediated Raptin cleavage from RCN2 and its secretion, an effect that is decreased by sleep deficiency. Raptin binds to metabotropic glutamate receptor 3 (mGluR3) in hypothalamic and gastric neurons to reduce appetite and gastric emptying, respectively. PVN-specific knockout of Rcn2 increases food intake and decreases energy expenditure in mice fed a high-fat diet. Plasma levels of Raptin are negatively correlated with sleep deficiency and obesity in humans, and a heterozygous RCN2 nonsense variant is associated with lower Raptin levels during the sleep phase and hyperphagia. Cayman's Raptin (human, recombinant) protein can be used for binding assay, ELISA, and Western blot (WB) applications.