The Arabidopsis Deubiquitinating Enzyme AMSH3 Interacts with ESCRT-III Subunits and Regulates Their Localization
The Arabidopsis Deubiquitinating Enzyme AMSH3 Interacts with ESCRT-III Subunits and Regulates Their Localization
复制标题
DOI：
10.1105/tpc.111.087254
复制
发表时间：
2011-08-01
期刊：
影响因子：
11.6
通讯作者：
Isono, Erika
中科院分区：
文献类型：
--
作者：
Katsiarimpa, Anthi;Anzenberger, Franziska;Isono, Erika
泛素化和去泛素化调节各种细胞过程。我们最近的研究表明，去泛素化酶与STAM 3的SH 3结构域相关分子（AMSH 3）参与拟南芥液泡生物发生和细胞内运输。然而，很少有人知道它的相互作用伙伴和去泛素化底物的身份。在这里，我们提供了AMSH 3与ESCRT-III亚基VPS2.1和VPS24.1相互作用的证据。ESCRT-III亚基与AMSH 3的相互作用由MIM 1结构域介导，并依赖于AMSH 3的MIT结构域。我们进一步表明，AMSH 3，VPS2.1和VPS24.1定位于E类车厢时，ESCRT-III的拆卸被抑制的共表达的非活性抑制剂K+转运缺陷1（SKD 1），AAA-ATP酶参与ESCRT-III的拆卸。我们还提供了AMSH 3和SKD 1竞争结合VPS2.1的证据。此外，我们发现AMSH 3酶活性的丧失导致形成含有AMSH 3、VPS2.1和VPS24.1的细胞隔室。总之，我们的研究提供了证据表明AMSH 3与经典的核心ESCRT-III组分相互作用，从而为AMSH 3在植物中的功能提供了分子框架。
Ubiquitination and deubiquitination regulate various cellular processes. We have recently shown that the deubiquitinating enzyme Associated Molecule with the SH3 domain of STAM3 (AMSH3) is involved in vacuole biogenesis and intracellular trafficking in Arabidopsis thaliana. However, little is known about the identity of its interaction partners and deubiquitination substrates. Here, we provide evidence that AMSH3 interacts with ESCRT-III subunits VPS2.1 and VPS24.1. The interaction of ESCRT-III subunits with AMSH3 is mediated by the MIM1 domain and depends on the MIT domain of AMSH3. We further show that AMSH3, VPS2.1, and VPS24.1 localize to class E compartments when ESCRT-III disassembly is inhibited by coexpression of inactive Suppressor of K+ transport Defect 1 (SKD1), an AAA-ATPase involved in the disassembly of ESCRT-III. We also provide evidence that AMSH3 and SKD1 compete for binding to VPS2.1. Furthermore, we show that the loss of AMSH3 enzymatic activity leads to the formation of cellular compartments that contain AMSH3, VPS2.1, and VPS24.1. Taken together, our study presents evidence that AMSH3 interacts with classical core ESCRT-III components and thereby provides a molecular framework for the function of AMSH3 in plants.