Other TGF-beta Superfamily Ligands
Additional TGF-beta superfamily ligands include Lefty, MIS and Nodal proteins. Lefty proteins are novel TGF-beta ligands that function as antagonists of Nodal signaling. Müllerian inhibiting substance (MIS), also named anti-Müllerian hormone (AMH), is a tissue-specific TGF-beta superfamily growth factor. Expression of MIS is restricted to Sertoli cells of fetal and postnatal testis, and to granulosa cells of the postnatal ovary. Nodal proteins play crucial roles in mesoderm formation and both anterior-posterior and left-right axis formation during vertebrate development.