Schwarz M A, Brown P J, Eveleth D D, Bradshaw R A
Department of Biological Chemistry, College of Medicine, University of California, Irvine 92717.
J Cell Physiol. 1989 Jan;138(1):121-8. doi: 10.1002/jcp.1041380117.
Rat pheochromocytoma PC12 cells respond to the binding of nerve growth factor (NGF) and basic fibroblast growth factor (bFGF) by extending neurites in a manner resembling sympathetic neurons. This response requires cell attachment to an appropriate substratum (Fujii et al., J. Neurosci., 2:1157, 1982); attachment factors which function in this capacity include the adhesive proteins fibronectin and laminin. Incubating PC12 cells with a polyclonal antiserum directed against a putative 140-kDa fibroblast cell surface fibronectin receptor (anti-gp140) perturbed spreading but not attachment of the cells to fibronectin and laminin substrates. However, in the presence of anti-gp 140 or its Fab fragments, NGF-stimulated neurite outgrowth was dramatically reduced. The antibody also caused a retraction of previously extended neurites. SDS-PAGE analysis of immunoprecipitates of PC12 cells surface labeled with 125I identified a prominent 120-140-kDa band, suggesting that the site of anti-gp140 action in PC12 cells is also through a fibronectin receptor.
大鼠嗜铬细胞瘤PC12细胞通过以类似于交感神经元的方式延伸神经突来响应神经生长因子（NGF）和碱性成纤维细胞生长因子（bFGF）的结合。这种反应需要细胞附着在合适的底物上（Fujii等人，《神经科学杂志》，2:1157，1982）；在此过程中起作用的附着因子包括粘附蛋白纤连蛋白和层粘连蛋白。用针对假定的140 kDa成纤维细胞表面纤连蛋白受体的多克隆抗血清（抗gp140）孵育PC12细胞，会干扰细胞在纤连蛋白和层粘连蛋白底物上的铺展，但不影响其附着。然而，在存在抗gp140或其Fab片段的情况下，NGF刺激的神经突生长会显著减少。该抗体还会导致先前延伸的神经突回缩。对用125I表面标记的PC12细胞免疫沉淀物进行的SDS-PAGE分析鉴定出一条突出的120 - 140 kDa条带，表明抗gp140在PC12细胞中的作用位点也是通过纤连蛋白受体。
