To provide: a safe effective substance inhibiting the signal transduction of a bone morphogenic protein (BMP); a method for producing the substance; a microorganism for producing the substance; and a medicine that contains the substance and is used for preventing or treating a disease caused by bone metabolism abnormality such as fibrodysplasia ossificans progressiva. 安全で効果的な骨形成タンパク質(BMP)のシグナル伝達を阻害する物質、該物質の製造方法、該物質を生産する微生物、および該物質を含有し進行性骨化性繊維異形成症などの骨代謝異常に起因する疾患の予防薬または治療薬の提供。 - 特許庁