The product contains the polyhedrin protein co-crystalized with Human BMP-5. BMP-5, also known as Bone Morphogenetic Protein 5, is a member of the TGF superfamily of proteins. Akin to the other functionally and structurally related bone morphogenic proteins (BMPs), BMP-5 is involved in cartilage and bone formation as BMP-5, along with BMP-6 and BMP-7, shares high sequence homology with BMP-2. Furthermore, BMP-5 is expressed by chondrocytes in proliferating bone growth plates and contributes to limb development by promoting proliferation and differentiation of chondrocytes as well as apoptosis of undifferentiated mesoderm. Outside the context of bone and cartilage, BMP-5 is expressed in the lung and liver as well as the trabecular meshwork and optic nerve head where it may have a role in the development and normal function. Furthermore, in the developing as well as adult nervous system, BMP-5 promotes dendrite outgrowth, morphology and dopaminergic neuronal differentiation. Analogous to other BMPs, BMP-5 is a disulfide-linked homodimer and highly conserved across animal species.