p62/SQSTM1-dependent autophagy of Lewy body-like α-synuclein inclusions.
p62/SQSTM1-dependent autophagy of Lewy body-like α-synuclein inclusions.
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DOI：
10.1371/journal.pone.0052868
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发表时间：
2012
期刊：
影响因子：
3.7
通讯作者：
Tanaka M
中科院分区：
文献类型：
--
作者：
Watanabe Y;Tatebe H;Taguchi K;Endo Y;Tokuda T;Mizuno T;Nakagawa M;Tanaka M
α-突触核蛋白是路易体的主要成分，路易体是帕金森病的特征性神经元内包涵体。虽然α-突触核蛋白的积累是由蛋白酶体和自噬-溶酶体的抑制引起的，但α-突触核蛋白包涵体的降解仍然是未知的。通过引入体外产生的α-突触核蛋白原纤维，可以在培养的细胞中复制Lewy小体样包涵体的形成。我们使用这种细胞培养模型来研究α-突触核蛋白包涵体和受损线粒体的自噬。细胞内α-突触核蛋白包涵体立即发生磷酸化和泛素化。同时，它们被衔接蛋白p62/SQSTM 1包围，并在HEK 293细胞系中被定向至自噬-溶酶体途径。大多数磷酸-α-突触核蛋白阳性包涵体在24 h内降解，然而，巴弗洛霉素A1的溶酶体功能障碍显著影响其清除。此外，通过Atg-5 siRNA处理抑制自噬减少了α-突触核蛋白内含物掺入LC 3阳性自噬体中。敲除实验证明了α-突触核蛋白自噬需要p62。这些结果表明，α-突触核蛋白包涵体是p62依赖性自噬的优选靶点。接下来，我们研究了在含有α-突触核蛋白包涵体的细胞中受损线粒体的自噬清除。即使在存在α-突触核蛋白包涵体的情况下，线粒体解偶联后受损的线粒体也几乎完全消除，这表明HEK 293细胞中的α-突触核蛋白包涵体不会阻止线粒体清除。
α-Synuclein is the main component of Lewy bodies, the intraneuronal inclusion bodies characteristic of Parkinson’s disease. Although α-synuclein accumulation is caused by inhibition of proteasome and autophagy-lysosome, the degradation of α-synuclein inclusions is still unknown. Formation of Lewy body-like inclusions can be replicated in cultured cells by introducing α-synuclein fibrils generated in vitro. We used this cell culture model to investigate the autophagy of α-synuclein inclusions and impaired mitochondria. The intracellular α-synuclein inclusions immediately underwent phosphorylation and ubiquitination. Simultaneously they were encircled by an adaptor protein p62/SQSTM1 and directed to the autophagy-lysosome pathway in HEK293 cell line. Most phospho-α-synuclein-positive inclusions were degraded in 24 h, however, lysosomal dysfunction with bafilomycin A1 significantly affected their clearance. Moreover, inhibition of autophagy by Atg-5 siRNA treatment reduced the incorporation of α-synuclein inclusions into LC3-positive autophagosomes. Knockdown experiments demonstrated the requirement of p62 for α-synuclein autophagy. These results demonstrate that α-synuclein inclusions are preferred targets for p62-dependent autophagy. Next, we investigated the autophagic clearance of impaired mitochondria in α-synuclein inclusion-containing cells. Impaired mitochondria were almost completely eliminated after mitochondrial uncoupling even in the presence of α-synuclein inclusions, suggesting that mitochondrial clearance is not prevented by α-synuclein inclusions in HEK293 cells.
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影响因子：
82.9
作者：
Conway, KA;Harper, JD;Lansbury, PT
通讯作者：
Lansbury, PT
DOI：
10.1083/jcb.200910140
发表时间：
2010-04-19
期刊：
The Journal of cell biology
影响因子：
--
作者：
Matsuda N;Sato S;Shiba K;Okatsu K;Saisho K;Gautier CA;Sou YS;Saiki S;Kawajiri S;Sato F;Kimura M;Komatsu M;Hattori N;Tanaka K
通讯作者：
Tanaka K
影响因子：
3.7
作者：
Crews L;Spencer B;Desplats P;Patrick C;Paulino A;Rockenstein E;Hansen L;Adame A;Galasko D;Masliah E
通讯作者：
Masliah E
DOI：
10.1083/jcb.200809125
发表时间：
2008-12-01
期刊：
The Journal of cell biology
影响因子：
--
作者：
Narendra D;Tanaka A;Suen DF;Youle RJ
通讯作者：
Youle RJ
影响因子：
4.7
作者：
Matsui, Hideaki;Ito, Hidefumi;Takahashi, Ryosuke
通讯作者：
Takahashi, Ryosuke