Myostatin activity and muscle growth

Regulation of myostatin activity and muscle growth. Myostatin is negatively regulated by various naturally-occurring binding proteins. When not bound to these inhibitory proteins, myostatin signals by binding initially to the two activin type II receptors, ACVR2 and ACVR2B, which then leads to binding and activation of the type I receptors, ALK4 and/or ALK5. Signaling through this pathway results in inhibition of muscle growth. Ligand “X” refers to the as yet unidentified TGF-ß related ligand or ligands that cooperate with myostatin to limit muscle growth. Components shown in red act to block muscle growth, and components shown in green act to promote muscle growth. As described in the text, ligand “X” can be blocked by either follistatin or FSTL-3, but whether ligand “X” can also be inhibited by other regulatory components is not known.

Publication

Extracellular Regulation of Myostatin: A Molecular Rheostat for Muscle Mass. (2010) Se-Jin Lee. Immunol Endocr Metab Agents Med Chem. 2010;10:183-194. Figure: F1. Homo sapiens

Disease mentions