Amyotrophic lateral sclerosis is a non-amyloid disease in which extensive misfolding of SOD1 is unique to the familial form
Amyotrophic lateral sclerosis is a non-amyloid disease in which extensive misfolding of SOD1 is unique to the familial form
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DOI：
10.1007/s00401-010-0646-5
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发表时间：
2010-03-01
影响因子：
12.7
通讯作者：
Chakrabartty, Avijit
中科院分区：
文献类型：
--
作者：
Kerman, Aaron;Liu, Hsueh-Ning;Chakrabartty, Avijit
肌萎缩侧索硬化症（ALS）是一种构象疾病，其中蛋白质如SOD 1（家族性ALS）和TDP-43（散发性ALS）的错误折叠和聚集是中心特征。在受影响的患者的运动神经元内，这些蛋白质所采用的构象尚不清楚。我们已经开发了一种新的构象特异性抗体（USOD）针对SOD 1残基42-48，特异性识别SOD 1，其中β桶是展开的。使用这种抗体，与先前描述的识别SOD 1二聚体界面的SEDI抗体结合，可以在残基特异性水平上详细研究SOD 1的体内构象。来自由SOD 1突变（A4 V和Delta G27/P28）引起的ALS病例的脊髓切片的USOD和SEDI免疫组织化学显示，剩余运动神经元内的内含物含有SOD 1，其具有未折叠的β桶和破坏的二聚体界面。错误折叠的SOD 1也可以使用USOD从这些病例的脊髓提取物中免疫沉淀。然而，在10例散发性ALS中，错误折叠的SOD 1未被免疫组织化学或免疫沉淀法检测到。使用淀粉样蛋白特异性染料，刚果红和硫磺素S，我们发现家族性ALS中的SOD 1阳性包涵体，以及散发性ALS中的TDP-43和泛素阳性包涵体，含有非淀粉样蛋白沉积物。我们的结论是，SOD 1错误折叠是不是一个功能的散发性ALS，和SOD 1-ALS和散发性ALS，而不是淀粉样疾病，是构象疾病，涉及无定形聚集的错误折叠蛋白。这些知识将为亚细胞事件提供新的见解，导致错误折叠，聚集和毒性。
Amyotrophic lateral sclerosis (ALS) is a conformational disease in which misfolding and aggregation of proteins such as SOD1 (familial ALS) and TDP-43 (sporadic ALS) are central features. The conformations adopted by such proteins within motor neurons in affected patients are not well known. We have developed a novel conformation-specific antibody (USOD) targeted against SOD1 residues 42-48 that specifically recognizes SOD1 in which the beta barrel is unfolded. Use of this antibody, in conjunction with the previously described SEDI antibody that recognizes the SOD1 dimer interface, allows a detailed investigation of the in vivo conformation of SOD1 at the residue-specific level. USOD and SEDI immunohistochemistry of spinal cord sections from ALS cases resulting from SOD1 mutations (A4V and Delta G27/P28) shows that inclusions within remaining motor neurons contain SOD1 with both an unfolded beta barrel and a disrupted dimer interface. Misfolded SOD1 can also be immunoprecipitated from spinal cord extracts of these cases using USOD. However, in ten cases of sporadic ALS, misfolded SOD1 is not detected by either immunohistochemistry or immunoprecipitation. Using the amyloid-specific dyes, Congo Red and Thioflavin S, we find that SOD1-positive inclusions in familial ALS, as well as TDP-43- and ubiquitin-positive inclusions in sporadic ALS, contain non-amyloid protein deposits. We conclude that SOD1 misfolding is not a feature of sporadic ALS, and that both SOD1-ALS and sporadic ALS, rather than being amyloid diseases, are conformational diseases that involve amorphous aggregation of misfolded protein. This knowledge will provide new insights into subcellular events that cause misfolding, aggregation and toxicity.