The N-terminal ubiquitin-binding region of ubiquitin-specific protease 28 modulates its deubiquitination function: NMR structural and mechanistic insights
The N-terminal ubiquitin-binding region of ubiquitin-specific protease 28 modulates its deubiquitination function: NMR structural and mechanistic insights
复制标题
泛素特异性蛋白酶 28 的 N 端泛素结合区调节其去泛素化功能：NMR 结构和机制见解
DOI：
10.1042/bj20150088
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发表时间：
2015-10-15
影响因子：
4.1
通讯作者：
Zhang, Naixia
中科院分区：
文献类型：
--
作者：
Wen, Yi;Shi, Li;Zhang, Naixia
去泛素酶泛素特异性蛋白水解酶28(USP28)含有一个泛素结合区(UBR)，在其N端由一个泛素相关结构域(UBA)和一个泛素相互作用基序(UIM)组成。有趣的是，在其UIM旁边还有一个额外的小泛素样修饰物(SUMO)相互作用基序(SIM)。到目前为止，Usp28 UBR的功能作用仍然不清楚。为了阐明UBR对USP28全功能显示的调控机制，本研究采用核磁共振和生化方法。获得了Usp28UBR的溶液结构，并确定了与泛素和SUMO1/2生态识别相关的关键残基。此外，我们发现Usp28 UBR的泛素结合能力是Usp28全酶活性所必需的，而SUMO1/2的结合通过竞争性地阻断其与泛素底物的相互作用而削弱了酶的催化活性。我们的发现为理解Usp28的酶活性是如何被其非催化UBR和内源配体调节的提供了第一个洞察力。
The deubiquitinase ubiquitin-specific protease 28 (Usp28) contains a ubiquitin-binding region (UBR) composed of one ubiquitin-associated domain (UBA) and one ubiquitin-interacting motif (UIM) at its N-terminus. It is of interest that an additional small ubiquitin-like modifier (SUMO)-interacting motif (SIM) is located next to its UIM. To date, the functional role of the Usp28 UBR is still not understood. To elucidate the regulatory mechanism of the UBR on the full functional display of Usp28, in the present study, NMR and biochemical approaches were applied. The solution structure of Usp28 UBR was obtained, and the key residues responsible for ubiquitin and SUMO1/2 ecognition were identified. In addition, we find that the ubiquitin-binding ability of Usp28 UBR was required for full enzymatic activity of Usp28, whereas binding of SUMO1/2 impaired the catalytic activity of the enzyme by competitively blocking its interactions with ubiquitin substrates. Our findings provide a first insight into understanding how the enzymatic activity of Usp28 is regulated by its non-catalytic UBR and endogenous ligands.