HOAM THE HO-AM FOUNDATION

Dr. Se-Jin Lee is a world-renowned scientist who made a notable discovery in the field of muscle growth and development. Dr. Lee discovered myostatin, a negative regulator of muscle growth, and elucidated the mechanisms by which myostatin acts. The growth of all tissues, including muscle, is regulated by various positive (accelerating growth) and negative (inhibiting growth) growth factors. Many such molecules have been discovered, and these can be classified into different groups depending on their structure. From the early-1990s, Dr. Lee began focusing on one such group of signaling molecules, referred to as the TGF-β family, which was known to play important roles in regulating cell growth and differentiation. Using molecular genetic approaches, his laboratory identified a large number of new members of this growth factor family. Among these new family members was one that they showed to be a potent inhibitor of muscle growth, and based on its biological function, they named this new molecule myostatin.

Dr. Lee found that myostatin is made by muscle and that genetically engineered mice lacking myostatin have about twice the normal muscle mass. Dr. Lee’s laboratory and his collaborators went on to show that naturally occurring mutations in the myostatin gene were responsible for the dramatic muscling seen in certain breeds of double-muscled cattle as well as in a muscular German boy. Dr. Lee also elucidated much of the myostatin signaling pathway, including identifying the cellular receptors for myostatin and binding proteins that normally inhibit myostatin activity. Dr. Lee’s discoveries launched an extensive effort directed at developing myostatin blocking agents for the treatment of patients with muscle loss. In this respect, several major pharmaceutical companies are currently conducting clinical trials testing myostatin inhibitors in patients with muscular dystrophy, cancer cachexia, hip fractures, and age-related muscle loss. For these achievements, Dr. Lee was elected a member of the National Academy of Sciences in 2012.