MISR II (anti-Muellerian hormone type-2 receptor, MIS type II receptor) is a 573 amino acid protein encoded by the human gene AMHR2. MISR II belongs to the protein kinase superfamily, TKL Ser/Thr protein kinase family, TGFB receptor subfamily and contains one protein kinase domain. Upon ligand binding, MISR II forms a receptor complex consisting of two type II and two type I transmembrane serine/threonine kinases. These type II receptors phospho-rylate and activate type I receptors which autophosphorylate, then bind and activate Smad transcriptional regulators. MISR II also acts as a receptor for anti-Muellerian hormone. Defects in AMHR2 are the cause of persistent Muellerian duct syndrome type 2 (PMDS-2). PMDS-2 is a form of male pseudo-hermaphroditism characterized by a failure of Muellerian duct regression in otherwise normal males.