N-syndecan (syndecan 3) from neonatal rat brain binds basic fibroblast growth factor.

摘要: The cell surface proteoglycan N-syndecan (syndecan 3) was isolated from neonatal rat brain. Purified brain had biochemical properties very similar to previously identified in Schwann cells: it contained mainly, if not exclusively, heparan sulfate glycosaminoglycan chains and a core protein with an apparent molecular mass of 120 kDa by sodium dodecyl sulfate-gel electrophoresis. We examined the interactions between purified extracellular ligands using solid phase binding assay. It found that among all proteins tested, including variety growth factors matrix molecules, only basic fibroblast factor (bFGF) exhibited significant binding. bFGF saturable KD = 0.5 nM. Soluble effectively competed immobilized for N-syndecan, indicating these two also interact solution. Heparin sulfate, but chondroitin inhibited N-syndecan-bFGF Isolated did exhibit bFGF. Thus, rather than its protein, appear be responsible Interestingly, acidic factor, which is structurally bFGF, bind several other heparin-binding used this study, high degree specificity interaction. Both are abundant brain, suggesting may function as co-receptor during nerve tissue development.