Ubiquitin C-Terminal Hydrolase L1 regulates autophagy by inhibiting autophagosome formation through its deubiquitinating enzyme activity
Ubiquitin C-Terminal Hydrolase L1 regulates autophagy by inhibiting autophagosome formation through its deubiquitinating enzyme activity
复制标题
泛素 C 末端水解酶 L1 通过其去泛素化酶活性抑制自噬体形成来调节自噬
DOI：
10.1016/j.bbrc.2018.02.140
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发表时间：
2018
影响因子：
3.1
通讯作者：
Liu Yanfen
中科院分区：
文献类型：
--
作者：
Yan Cong;Huo Huanhuan;Yang Cuiwei;Zhang Tao;Chu Yuanyuan;Liu Yanfen
泛素化修饰已被证明在自噬中起关键作用。越来越多的研究报道去泛素化酶（DUBs）参与自噬途径。为了系统地研究DUB如何操纵自噬，我们利用双荧光标记的LC 3稳定的HeLa细胞系，并对55个人DUB进行了全基因组筛选，其覆盖了DUB家族的约60%。我们发现一系列DUB通过改变LC 3斑点形成或自噬通量对自噬产生影响。其中之一是与帕金森病相关的泛素C末端水解酶L1（UCHL 1），通过抑制自噬体形成强烈影响自噬。我们发现UCHL 1过表达抑制LC 3斑点的形成，并依赖于其DUB活性。UCHL 1的敲除显著促进LC 3斑点的形成。进一步的研究表明，UCHL 1可能通过与LC 3相互作用而不是与其他自噬相关蛋白相互作用来影响自噬。有趣的是，帕金森病相关突变体UCHL 1 I93 M缺陷其DUB活性，并且不再能抑制自噬体形成。我们进一步筛选了22种市售DUB抑制剂，发现两种有效的UCHL 1抑制剂LDN-57444（LDN）和NSC 632839（NSC）在处理细胞时均强烈诱导LC 3斑点形成。总之，我们的研究结果表明了DUB调节自噬的方式的新见解，并为帕金森病提供了潜在的药物。
Ubiquitination modification has been shown to play a key role in autophagy. Increasing studies reported the involvement of de-ubiquitinating enzymes (DUBs) in autophagy pathway. To systematically search how DUBs manipulate autophagy, we utilized a double fluorescence tagged LC3 stable HeLa cell line, and did a genome wide screen of 55 human DUBs which is about 60% coverage of the DUB family. We found a bunch of DUBs have impact on autophagy by either changing the LC3 puncta formation or the autophagy flux. One of them, Ubiquitin C-Terminal Hydrolase L1 (UCHL1) correlated to Parkinson's disease, strongly affects autophagy by inhibiting autophagosome formation. We found UCHL1 overexpression inhibits LC3 puncta formation and is dependent on its DUB activity. Knockdown of UCHL1 significantly promotes LC3 puncta formation. Further study revealed that UCHL1 may affect autophagy by interacting with LC3 but not other autophagy related proteins. Interestingly, a Parkinson's disease related mutant UCHL1 I93 M defects its DUB activity and can no longer inhibit autophagosome formation. We further screened 22 commercially available DUB inhibitors and found two potent UCHL1 inhibitors LDN-57444 (LDN) and NSC632839 (NSC), when treating cells, both strongly induce LC3 puncta formation. Taken together, our results indicated a new insight into the manner in which DUB regulates autophagy and provided potential drugs for the Parkinson's disease.