Neurite outgrowth in dorsal root neuronal hybrid clones modulated by ganglioside GM1 and disintegrins.
Neurite outgrowth in dorsal root neuronal hybrid clones modulated by ganglioside GM1 and disintegrins.
复制标题
由神经节苷脂 GM1 和解整合素调节的背根神经元杂交克隆中的神经突生长。
DOI：
10.1016/0014-4827(91)90543-4
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发表时间：
1991
影响因子：
3.7
通讯作者：
Culp,LA
中科院分区：
文献类型：
--
作者：
Barletta,E;Bremer,EG;Culp,LA
F11神经元杂交细胞（神经母细胞瘤×背根神经节神经元）的亚克隆在三种基质上分离出不同和/或重叠的神经突发生机制：具有多种受体活性的血浆纤连蛋白（pFN）、与神经节苷脂GM 1结合的霍乱毒素B亚基（CT B）和与硫酸乙酰肝素蛋白聚糖结合的血小板因子4（PF 4）。在这项研究中，特定的细胞表面受体活性的三种基质进行了测试，其调制过程中的神经突，通过几个实验范例，使用F11亚克隆代表三个分化类（神经突上的pFN，CTB，只有或所有三个基质）。当放线菌酮被包括在介质中，以抑制蛋白质的合成在活动期间，神经突的形成显着增加forall亚克隆在所有三个substrata，几乎消除基板的选择性分化介导的细胞表面整合素，神经节苷脂GM 1，或硫酸乙酰肝素蛋白聚糖。因此，一种或多种不稳定蛋白质（称为去整合素）必须调节基质受体（例如，整合素）介导神经突形成。为了验证环己酰亚胺诱导的轴突发生是否也受到整合素与细胞表面GM 1相互作用的调节，使用了两种方法。当含有（Arg-Gly-Asp-Ser）的肽A加入到培养基中时，它完全抑制了环己酰亚胺诱导的所有亚克隆的所有三种基质上的神经突发生，表明在这些机制中对细胞表面整合素功能的严格要求。与此相反，当CTB或单克隆抗GM 1抗体也加入到培养基中，环己酰亚胺诱导的轴突发生进一步放大pFN和肽A抑制的敏感性被废除。因此，在某些情况下，神经节苷脂GM 1必须与细胞表面的整合素受体复合以调节其功能。这些结果还表明，（a）放线菌酮治疗导致神经突发生中基质选择性的丧失，（B）神经突生长的这种负调节受到整联蛋白受体与不稳定调节蛋白（去整联蛋白）以及GM 1的结合的影响，以及（c）GM 1与多价GM 1结合蛋白的复合使神经突发生从RGDS依赖性整联蛋白机制转变为RGDS非依赖性受体机制。
Subclones of F11 neuronal hybrid cells (neuroblastoma × dorsal root ganglion neurons) have segregated differing and/or overlapping neuritogenic mechanisms on three substrata—plasma fibronectin (pFN) with its multiple receptor activities, cholera toxin B subunit (CTB) for binding to ganglioside GM1, and platelet factor-4 (PF4) for binding to heparan sulfate proteoglycans. In this study, specific cell surface receptor activities for the three substrata were tested for their modulation during neuritogenesis by several experimental paradigms, using F11 subclones representative of three differentiation classes (neuritogenic on pFN only, on CTB only, or on all three substrata). When cycloheximide was included in the medium to inhibit protein synthesis during the active period, neurite formation increased significantly forall subclones on all three substrata, virtually eliminating substratum selectivity for differentiation mediated by cell surface integrin, ganglioside GM1, or heparan sulfate proteoglycans. Therefore, one or more labile proteins (referred to asdisintegrins) must modulate functions of matrix receptors (e.g., integrins) mediating neurite formation. To verify whether cycloheximide-induced neuritogenesis was also regulated by integrin interaction with cell surface GM1, two approaches were used. When (Arg-Gly-Asp-Ser)-containing peptide A was added to the medium, it completely inhibited cycloheximide-induced neuritogenesison all three substrata of all subclones, indicating stringent requirement for cell surface integrin function in these mechanisms. In contrast, when CTB or a monoclonal anti-GM1 antibody was also added to the medium, cycloheximide-induced neuritogenesis was amplified further on pFN and sensitivity to peptide A inhibition was abolished. Therefore, in some contexts ganglioside GM1 must complex with integrin receptors at the cell surface to modulate their function. These results also indicate that (a) cycloheximide treatment leads to loss of substratum selectivity in neuritogenesis, (b) this negative regulation of neurite outgrowth is affected by integrin receptor association with labile regulatory proteins (disintegrins) as well as with GM1, and (c) complexing of GM1 by multivalent GM1-binding proteins shifts neuritogenesis from an RGDS-dependent integrin mechanism to an RGDS-independent receptor mechanism.