making muscle wasting history

Myostatin is produced in muscle cells as an inactive protein consisting of 375 amino acids. It circulates in the bloodstream as an inactive molecule. When it’s so-called propeptide is degraded, myostatin is activated and binds to a receptor protein, called activin type II, in the muscle cell membrane. The receptor-bound myostatin initiates a chain (a cascade) of chemical reactions that reaches the muscle cell nucleus and blocks muscle- forming genes. Thus, myostatin limits the growth of muscles.

There are cattle, the Belgian Blue Breed, and dogs, bully whippets, which are very muscular because their myostatin gene is inactivated by a mutation. And in Berlin, a physically very strong boy without myostatin was identified in 1999, whose skeletal muscles are about twice as large as those of a normal child.