Phosphorylated α-synuclein is ubiquitinated in α-synucleinopathy lesions
Phosphorylated α-synuclein is ubiquitinated in α-synucleinopathy lesions
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DOI：
10.1074/jbc.m208046200
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发表时间：
2002-12-13
影响因子：
4.8
通讯作者：
Iwatsubo, T
中科院分区：
文献类型：
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作者：
Hasegawa, M;Fujiwara, H;Iwatsubo, T
α-突触核蛋白是神经退行性疾病亚组的脑中细胞内聚集体的主要组分之一，所述神经退行性疾病亚组包括帕金森病、路易体痴呆、多系统萎缩和Hallervorden-Spatz病，其被称为α-突触核蛋白病。我们以前已经表明（Fujiwara，H.，Hasegawa，IVL，Dohmae，N.，Kawashima，A.，Masliah，E.，Goldberg，IVL S.，沈，J.，Takio，K.，和lwatsubo，T.（2002）Nat. Cell Biol.4，160-164），沉积在突触核蛋白病脑中的α-突触核蛋白在Ser-129处被广泛磷酸化，并在15 kDa处迁移。在这里，我们研究了另外的，更高分子量的种类的磷酸化α-突触核蛋白阳性多肽，也回收在Sarkosyl不溶性部分的突触核蛋白病和迁移在约22和29 kDa的生化特性。这些22和29 kDa的条带是阳性的三种不同的抗泛素抗体和comigrated完美的体外泛素化的α-突触核蛋白，可能对应于单和双泛素化的α-突触核蛋白，分别。此外，溴化氰切割的22和29 kDa的多肽移动到19和26 kDa，分别，他们保留免疫反应性的泛素和α-突触核蛋白。最后，蛋白质序列分析表明，19 kDa的条带含有两个氨基末端序列的α-突触核蛋白和泛素。这些结果有力地表明，磷酸化的α-突触核蛋白是针对单和双泛素化的突触核蛋白病的大脑，这可能对这些疾病的机制的影响。
alpha-Synuclein is one of the major components of intracellular fibrillary aggregates in the brains of a subset of neurodegenerative disorders, including Parkinson's disease, dementia with Lewy bodies, multiple system atrophy, and Hallervorden-Spatz disease, which are referred to as alpha-synucleinopathies. We have shown previously (Fujiwara, H., Hasegawa, IVL, Dohmae, N., Kawashima, A., Masliah, E., Goldberg, IVL S., Shen, J., Takio, K., and lwatsubo, T. (2002) Nat. Cell Biol. 4, 160-164) that alpha-synuclein deposited in synucleinopathy brains is extensively phosphorylated at Ser-129 and migrates at 15 kDa. Here we examined the biochemical characteristics of the additional, higher molecular mass species of phosphorylated alpha-synuclein-positive polypeptides that also are recovered in the Sarkosyl-insoluble fraction of synucleinopathy and migrate at about 22 and 29 kDa. These 22 and 29 kDa bands were positive for three different anti-ubiquitin antibodies and comigrated perfectly with in vitro ubiquitinated alpha-synuclein that may correspond to mono- and diubiquitinated alpha-synuclein, respectively. Furthermore, cyanogen bromide cleavage of the 22 and 29 kDa polypeptides shifted the mobility to 19 and 26 kDa, respectively, and they retained immunoreactivity for both ubiquitin and alpha-synuclein. Finally, protein sequence analysis showed that the 19 kDa band contained two amino-terminal sequences of alpha-synuclein and ubiquitin. These results strongly suggest that phosphorylated alpha-synuclein is targeted to mono- and diubiquitination in synucleinopathy brains, which may have implications for mechanisms of these diseases.