Noggin (NOG) binds to and antagonizes bone morphogenetic protein (BMP) ligands of the transforming growth factor beta (TGF-β) family. NOG supports maintenance of undifferentiated human embryonic stem cells in vitro, and can be used to prevent spontaneous differentiation in the short term. NOG is essential for development of structures derived from ectoderm embryonic somite, skeletal patterning, and neurogenesis in vivo. It also influences chondrogenesis, osteogenesis, and joint formation, and promotes dopaminergic differentiation of embryonic stem cells and subsequent survival of dopamine neurons.
