LEPTIN, OB-RECEPTOR AND OBESITY

The effect of obese(ob)-protein (leptin) and ob-receptor on body weigh t regulation and obesity are reviewed. Investigation of genetic compon ents of obesity resulted in the identification of the obese-gen and it s protein-product leptin, which seems to be part of the >>saturity<< s ignaling-pathway of adipocytes. Injection of ob-protein into leptin-de ficient ob/ob-mice causes the animals to lose body weight. Another mou se-species (db/db-mice) was identified to possess a defective ob-recep tor. Recently, the mouse-ob-receptor gene and its human analogue were identified and the leptin-receptor was cloned. Alternative splicing of the nuclear RNA was reported to generate different subtypes of the ob -receptor. A mutation of the ob-receptor gene was found in db/db-mice truncating the intracellular receptor domaine, but it is only one of s everal mutations of the ob-receptor gene. Further investigations of th is might contribute to the better understanding of certain forms of ob esity.