Growth Differentiation Factor-5, also known as BMP-14 and CDMP-1, is a member of the BMP family of TGF-beta superfamily proteins. GDF-5 signaling is mediated by formation of a heterodimeric complex consisting of a type 1 (BMPR-IB) and a type II (BMPR-II or Activin RII) serine/threonine kinase receptor which results in the phosphorylation and activation of cytosolic Smad proteins (Smad1, 5, and 8). Its signaling is antagonized by Noggin. GDF-5 is involved in multiple developmental processes including limb generation, cartilage development, joint formation, bone morphogenesis, cell survival, and neuritogenesis. GDF-5 can promote chondrogenesis, osteogenesis, and angiogenesis in mesenchymal stem cells.
