Adaptor linked K63 di-ubiquitin activates Nedd4/Rsp5 E3 ligase.
Adaptor linked K63 di-ubiquitin activates Nedd4/Rsp5 E3 ligase.
复制标题
衔接子连接的K63二泛素激活Nedd 4/Rsp 5 E3连接酶。
DOI：
10.7554/elife.77424
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发表时间：
2022-06-30
期刊：
影响因子：
7.7
通讯作者：
Emr, Scott D.
中科院分区：
文献类型：
--
作者：
Zhu, Lu;Zhang, Qing;Cordeiro, Ciro D.;Banjade, Sudeep;Sardana, Richa;Mao, Yuxin;Emr, Scott D.
Nedd4/Rsp5家族E3连接酶介导了许多细胞过程，其中许多需要E3连接酶与含有连接蛋白的PY基序相互作用。RSP5的几个arrestin相关的运输适配子(ARTS)被自身泛素化激活，但调节机制仍然难以捉摸。值得注意的是，我们证明了Art1、Art4和Art5经历了K63连接的Rsp5的二泛素化。这种修饰增强了Art1或Art5在底物诱导时对Rsp5的质膜募集，这是货物蛋白泛素化所必需的。与这些观察结果一致，我们发现二泛素加强了Rsp5与Art1、Pub1和Any1的pombe同源物之间的相互作用。此外，我们发现E6AP C-末端(Hect)结构域的同源物可以保护K63连接的二泛素不被脱泛素化酶Ubp2切割。总之，我们的研究发现了一种由Rsp5接头蛋白实现的新的泛素化修饰，强调了接头蛋白如何控制Rsp5的招募和Rsp5对膜蛋白周转的活性的调节机制。
Nedd4/Rsp5 family E3 ligases mediate numerous cellular processes, many of which require the E3 ligase to interact with PY motif containing adaptor proteins. Several arrestin-related trafficking adaptors (ARTs) of Rsp5 were self-ubiquitinated for activation, but the regulation mechanism remains elusive. Remarkably, we demonstrate that Art1, Art4, and Art5 undergo K63-linked di-ubiquitination by Rsp5. This modification enhances the plasma membrane recruitment of Rsp5 by Art1 or Art5 upon substrate induction, required for cargo protein ubiquitination. In agreement with these observations, we find that di-ubiquitin strengthens the interaction between the pombe orthologs of Rsp5 and Art1, Pub1, and Any1. Furthermore, we discover that the homologous to E6AP C-terminus (HECT) domain exosite protects the K63-linked di-ubiquitin on the adaptors from cleavage by the deubiquitination enzyme Ubp2. Together, our study uncovers a novel ubiquitination modification implemented by Rsp5 adaptor proteins, underscoring the regulatory mechanism of how adaptor proteins control the recruitment, and activity of Rsp5 for the turnover of membrane proteins.