Identification of a structural site on acetylcholinesterase that promotes neurite outgrowth and binds laminin-1 and collagen IV
Identification of a structural site on acetylcholinesterase that promotes neurite outgrowth and binds laminin-1 and collagen IV
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DOI：
10.1016/j.bbrc.2004.05.018
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发表时间：
2004-06-25
影响因子：
3.1
通讯作者：
Moore, SW
中科院分区：
文献类型：
--
作者：
Johnson, G;Moore, SW
乙酰胆碱酯酶的细胞粘附和神经突生长促进功能已定位于外周阴离子部位区域。为了精确地确定所涉及的位点，我们使用了代表外周阴离子位点及其周围序列的合成肽，并研究了它们与一组单克隆抗体的结合，这些单克隆抗体抑制细胞粘附/神经突生长和/或识别外周阴离子位点。与层粘连蛋白-1和IV型胶原的结合也进行了研究。对序列37-50的识别与细胞粘附的抑制程度之间存在关系，序列37-50代表与周围阴离子位点相邻的表面环；层粘连蛋白-1和胶原IV也以高亲和力结合该环。涂有这种肽的盖层上的神经突生长与涂有乙酰胆碱酯酶的盖层上的神经突生长相似。粘连抑制抗体也能识别69-96环，层粘连蛋白1和胶原蛋白IV也能识别。层粘连蛋白也能结合序列55-66和340-353，抗体能不同程度地识别，但胶原蛋白不能。这些多肽均能在一定程度上促进神经突生长。没有观察到配体与淀粉样蛋白结合的-环275-304结合，抗体也没有一致地识别这一点。没有观察到乙酰胆碱酯酶的抑制程度与抗体对神经突生长的抑制程度之间的关系，由此我们得出结论，神经突生长功能是非胆碱能的。总之，我们已经确定了乙酰胆碱酯酶的特定构象结构，包括37-50和69-96残基之间的相邻表面环，以及55-66和340-353序列，介导细胞粘附和神经突生长。爱思唯尔公司版权所有。
The cell adhesion and neurite outgrowth-promoting function of acetylcholinesterase has been localised to the area of the peripheral anionic site. In order to precisely determine the site involved, we used synthetic peptides representing sequences of the peripheral anionic site and its surrounds, and investigated their binding to a panel of monoclonal antibodies that inhibit cell adhesion/neurite outgrowth and/or to recognise the peripheral anionic site. Binding to laminin-1 and collagen IV was also investigated. A relationship between recognition of the sequence 37-50, representing a surface loop adjacent to the peripheral anionic site, and the degree of inhibition of cell adhesion was observed; both laminin-1 and collagen IV also bound this loop with high affinity. Neurite outgrowth on coverslips coated with this peptide was similar to those coated with acetylcholinesterase itself. Adhesion-inhibiting antibodies also recognised the omega loop 69-96, as did laminin-1 and collagen IV. Laminin also bound the sequences 55-66 and 340-353, recognised by the antibodies to varying degrees, but collagen did not. All these peptides were able to promote neurite outgrowth to some degree. No binding to the amyloid-binding omega loop 275-304 by the ligands was observed, nor did the antibodies recognise this consistently. No relationship was observed between the degree of inhibition of acetylcholinesterase and inhibition of neurite outgrowth by the antibodies from which we conclude that the neurite outgrowth function is non-cholinergic. In conclusion, we have identified a specific conformational structure on acetylcholinesterase, comprising adjacent surface loops between residues 37-50 and 69-96, with additional involvement of the sequences 55-66 and 340-353, that mediates cell adhesion and neurite outgrowth. (C) Elsevier Inc. All rights reserved.