Growth factor involved in osteogenesis and adipogenesis. Plays an inhibitory role in the process of osteoblast differentiation via SMAD2/3 pathway. Plays an inhibitory role in the process of adipogenesis. Homodimer or heterodimer. Can form a non-covalent complex of the mature region and the pro-region. Expressed in femur, brain, lung, skeletal muscle, pancreas and testis. Belongs to the TGF-beta family.