Gai W P, Power J H, Blumbergs P C, Culvenor J G, Jensen P H
Department of Human Physiology and Centre for Neuroscience, Flinders University, Bedford Park, South Australia.
J Neurochem. 1999 Nov;73(5):2093-100.
Immunohistochemical studies have shown that oligodendroglial inclusions in multiple system atrophy contain alpha-synuclein, a synaptic protein also found in Lewy bodies in Parkinson's disease. We have now used density gradient enrichment and an anti-alpha-synuclein immunomagnetic technique to isolate pure and morphologically intact oligodendroglial inclusions from brain white matter of patients dying with multiple system atrophy. Filamentous inclusion structures were obtained only from multiple system atrophy tissue, but not from normal brain tissues, or from multiple system atrophy tissue processed without anti-alpha-synuclein antibody. We confirmed the purity and morphology of isolated inclusions by electron microscopy. The inclusions comprised multiple protein bands after separation by polyacrylamide gel electrophoresis. Immunoblotting demonstrated that these proteins included alpha-synuclein, alphaB-crystallin, tubulins, ubiquitin, and prominent, possibly truncated alpha-synuclein species as high-molecular-weight aggregates. Our study provides the first biochemical evidence that oligodendroglial inclusion filaments consist of multiple protein components, suggesting that these inclusions may form as a result of multiprotein interactions with alpha-synuclein.
免疫组织化学研究表明，多系统萎缩中的少突胶质细胞内含物含有α-突触核蛋白，这是一种在帕金森病路易小体中也能发现的突触蛋白。我们现在利用密度梯度富集和抗α-突触核蛋白免疫磁技术，从死于多系统萎缩的患者脑白质中分离出纯净且形态完整的少突胶质细胞内含物。丝状内含物结构仅从多系统萎缩组织中获得，而非正常脑组织，也不是未经抗α-突触核蛋白抗体处理的多系统萎缩组织。我们通过电子显微镜确认了分离出的内含物的纯度和形态。经聚丙烯酰胺凝胶电泳分离后，内含物包含多条蛋白带。免疫印迹显示这些蛋白质包括α-突触核蛋白、αB-晶状体蛋白、微管蛋白、泛素，以及作为高分子量聚集体的显著的、可能截短的α-突触核蛋白种类。我们的研究提供了首个生化证据，表明少突胶质细胞内含物细丝由多种蛋白质成分组成，这表明这些内含物可能是多种蛋白质与α-突触核蛋白相互作用的结果。
