Follistatin 1MG is a 1-milligram format of follistatin, an activin binding glycoprotein best known for binding and neutralizing members of the TGF beta superfamily. Researchers study follistatin in the context of activin and myostatin signaling, endocrine regulation, and tissue biology in preclinical models. Experimental work has also examined how follistatin modulates ligand availability across cell culture and animal research systems.