Solution structure of the SGTA dimerisation domain and investigation of its interactions with the ubiquitin-like domains of BAG6 and UBL4A.
Solution structure of the SGTA dimerisation domain and investigation of its interactions with the ubiquitin-like domains of BAG6 and UBL4A.
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DOI：
10.1371/journal.pone.0113281
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发表时间：
2014
期刊：
影响因子：
3.7
通讯作者：
Isaacson RL
中科院分区：
文献类型：
--
作者：
Darby JF;Krysztofinska EM;Simpson PJ;Simon AC;Leznicki P;Sriskandarajah N;Bishop DS;Hale LR;Alfano C;Conte MR;Martínez-Lumbreras S;Thapaliya A;High S;Isaacson RL
BAG 6复合物存在于胞质溶胶中，并作为分选点沿着其适当的路径靶向不同的疏水蛋白底物，包括蛋白酶体降解和ER膜插入。由BAG 6、TRC 35和UBL 4A的三聚体复合物组成，BAG 6复合物与SGTA密切相关，SGTA是一种共分子伴侣，它可以从中获得疏水底物。SGTA由N-末端二聚化结构域（SGTA_NT）、中心三肽重复（TPR）结构域和朝向C-末端的谷氨酰胺富集区组成。在这里，我们解决了SGTA二聚化结构域的溶液结构，并使用生物物理技术来研究其与BAG 6复合物中两个不同UBL结构域的相互作用。SGTA_NT结构是具有连接两组四个α螺旋的紧密疏水界面的二聚体。使用NMR化学位移扰动，等温滴定量热法（ITC）和微量热泳（MST）实验的组合，我们已经生化特性的相互作用SGTA与BAG 6复合物的组分，泛素样结构域（UBL）含有蛋白质UBL 4A和BAG 6。我们证明了来自UBL 4A和BAG 6的UBL结构域直接竞争在相同位点与SGTA结合。使用结构和相互作用数据的组合，我们已经实现了HADDOCK蛋白质-蛋白质相互作用对接工具来生成SGTA-UBL复合物的模型。这种原子水平的信息有助于我们理解疏水蛋白的命运是由SGTA和BAG 6复合物之间的合作决定的。
The BAG6 complex resides in the cytosol and acts as a sorting point to target diverse hydrophobic protein substrates along their appropriate paths, including proteasomal degradation and ER membrane insertion. Composed of a trimeric complex of BAG6, TRC35 and UBL4A, the BAG6 complex is closely associated with SGTA, a co-chaperone from which it can obtain hydrophobic substrates. SGTA consists of an N-terminal dimerisation domain (SGTA_NT), a central tetratricopeptide repeat (TPR) domain, and a glutamine rich region towards the C-terminus. Here we solve a solution structure of the SGTA dimerisation domain and use biophysical techniques to investigate its interaction with two different UBL domains from the BAG6 complex. The SGTA_NT structure is a dimer with a tight hydrophobic interface connecting two sets of four alpha helices. Using a combination of NMR chemical shift perturbation, isothermal titration calorimetry (ITC) and microscale thermophoresis (MST) experiments we have biochemically characterised the interactions of SGTA with components of the BAG6 complex, the ubiquitin-like domain (UBL) containing proteins UBL4A and BAG6. We demonstrate that the UBL domains from UBL4A and BAG6 directly compete for binding to SGTA at the same site. Using a combination of structural and interaction data we have implemented the HADDOCK protein-protein interaction docking tool to generate models of the SGTA-UBL complexes. This atomic level information contributes to our understanding of the way in which hydrophobic proteins have their fate decided by the collaboration between SGTA and the BAG6 complex.
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影响因子：
64.8
作者：
Hessa, Tara;Sharma, Ajay;Mariappan, Malaiyalam;Eshleman, Heather D.;Gutierrez, Erik;Hegde, Ramanujan S.
通讯作者：
Hegde, Ramanujan S.
影响因子：
3.7
作者：
Claessen JH;Ploegh HL
通讯作者：
Ploegh HL
影响因子：
4.8
作者：
Seidel, Susanne A. I.;Dijkman, Patricia M.;Lea, Wendy A.;van den Bogaart, Geert;Jerabek-Willemsen, Moran;Lazic, Ana;Joseph, Jeremiah S.;Srinivasan, Prakash;Baaske, Philipp;Simeonov, Anton;Katritch, Ilia;Melo, Fernando A.;Ladbury, John E.;Schreiber, Gideon;Watts, Anthony;Braun, Dieter;Duhr, Stefan
通讯作者：
Duhr, Stefan
影响因子：
4
作者：
Leznicki, Pawel;Clancy, Anne;High, Stephen
通讯作者：
High, Stephen
影响因子：
3.9
作者：
Liou, ST;Wang, C
通讯作者：
Wang, C