Pountney Dean L, Raftery Mark J, Chegini Fariba, Blumbergs Peter C, Gai Wei Ping
School of Medical Science, Griffith Institute of Health and Medical Research, Griffith University, Gold Coast Campus, Queensland, QLD, 4222, Australia.
Acta Neuropathol. 2008 Dec;116(6):603-14. doi: 10.1007/s00401-008-0437-4. Epub 2008 Oct 3.
Neuronal intranuclear inclusion disease, a progressive ataxia that may be familial or sporadic, is characterized by numerous neuronal intranuclear inclusion bodies similar to those found in polyglutamine repeat diseases. Previously, we found that the intranuclear inclusion bodies are intensely immunopositive for SUMO-1, a protein which covalently conjugates to other proteins in a similar way to ubiquitin. To identify the SUMO-1-associated proteins in the inclusion bodies, we isolated intranuclear inclusion bodies from fresh, frozen brain tissue of a case with familial neuronal intranuclear inclusion disease and solubilized the proteins. SUMO-1-associated inclusion body proteins were then immunocaptured using an anti-SUMO-1 antibody. The proteins, NSF, dynamin-1 and Unc-18-1 (rbSEC1), involved in membrane trafficking of proteins, and the chaperone HSP90, were identified following anti-SUMO-1-immunocapture by using tandem mass spectrometry and database searching. Immunohistochemistry of brain sections and crude brain homogenates of three cases of familial neuronal intranuclear inclusion disease confirmed the presence of these proteins in intranuclear inclusions.
神经元核内包涵体病是一种可能为家族性或散发性的进行性共济失调，其特征是存在大量与多聚谷氨酰胺重复疾病中发现的类似的神经元核内包涵体。此前，我们发现核内包涵体对SUMO-1呈强免疫阳性，SUMO-1是一种蛋白质，它以与泛素类似的方式与其他蛋白质共价结合。为了鉴定包涵体中与SUMO-1相关的蛋白质，我们从一例家族性神经元核内包涵体病患者的新鲜冷冻脑组织中分离出核内包涵体并溶解其中的蛋白质。然后使用抗SUMO-1抗体免疫捕获与SUMO-1相关的包涵体蛋白。通过串联质谱分析和数据库搜索，在抗SUMO-1免疫捕获后鉴定出参与蛋白质膜转运的蛋白质NSF、动力蛋白-1和Unc-18-1（rbSEC1）以及伴侣蛋白HSP90。对三例家族性神经元核内包涵体病患者的脑切片和粗脑匀浆进行免疫组织化学分析，证实了这些蛋白质存在于核内包涵体中。
