Organic Matrices and Mineral Crystallites in Vertebrate Scales, Teeth and Skeletons

摘要: Synopsis. The earliest fossil vertebrates, the ostracoderms, more than 500,000,000 years ago had skeletons which included hard tissues calcified cartilage, bone, dentine and enamel. It seems plausible that modes of mineralization pioneered in these primitive have persisted throughout vertebrate radiation without major changes. All four types utilize calcium phosphate mineral apatite to form inorganic crystallites develop close association with matrix proteins. In collagen-associated tissues? bone dentine?the short, needle- or lath-like along collagen fibrils. Non-collagenous components include proteoglycans, glycoproteins vesicles. Special calcium-binding phosphatebinding constituents may promote crystal nucleation growth. enamel (enameloid) large hexagonal amelogenin enamelin secreted by cells ofthe inner dental epithelium (ameloblasts). Enamel shark tooth resembles mammalian size shape crystallites. Bio? chemical immunohistochemical techniques are being used several laboratories determine how proteins control enamel, whether they homologous all classes.