Cloning, purification and characterization of the Caenorhabditis elegans small glutamine-rich tetratricopeptide repeat-containing protein.
Cloning, purification and characterization of the Caenorhabditis elegans small glutamine-rich tetratricopeptide repeat-containing protein.
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DOI：
10.1016/j.bbapap.2007.12.003
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发表时间：
2008-03
期刊：
影响因子：
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通讯作者：
L. Worrall;M. Wear;A. P. Page;M. Walkinshaw
中科院分区：
文献类型：
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作者：
L. Worrall;M. Wear;A. P. Page;M. Walkinshaw
我们已经克隆并表达了假定的秀丽隐杆线虫富含谷氨酰胺的三肽重复序列蛋白的直向同源物，现在在C. elegans基因组数据库通过交联、质谱和凝胶过滤实验对纯化的蛋白质进行表征，提供了SGT-1在溶液中形成同源二聚体的明确证据。SGT-1二聚体相对于其分子量的流体动力学尺寸表明蛋白质具有低水平的紧凑性和扩展的构象。已显示人SGT通过TPR结构域介导的相互作用与热休克蛋白Hsp 70和Hsp 90相互作用并调节其活性。克隆、纯化SGT TPR结构域（SGT-1-TPR，残基100-226），并通过ITC和CD分析显示其与Hsp 70和Hsp 90的C-末端肽以相当的亲和力相互作用，尽管没有证据表明最近提出的TPR结构域的偶联结合-折叠机制。
We have cloned and expressed the putative Caenorhabditis elegans orthologue for small glutamine-rich tetratricopeptide repeat-containing protein, now assigned the gene name sgt-1 in the C. elegans genome database. Characterization of the purified protein by cross-linking, mass spectrometry and gel filtration experiments provides unambiguous evidence that SGT-1 forms homo-dimers in solution. The hydrodynamic dimensions of SGT-1 dimers in relation to their molecular weight suggest a protein with a low level of compactness and an extended conformation. Human SGT has been shown to interact with and regulate the activity of heat shock proteins Hsp70 and Hsp90 via a TPR domain mediated interaction. The SGT TPR domain (SGT-1-TPR, residues 100–226) was cloned, purified and shown by ITC and CD analysis to interact with the C-terminal peptides of Hsp70 and Hsp90 with comparable affinities although there is no evidence of a recently proposed coupled binding–folding mechanism for TPR domains.