摘要
铜转运蛋白hCtr1细胞膜内的C端区域对于细胞的铜转运过程具有重要作用,然而这一结构域对铜离子的捕获和胞内蛋白的铜分布机理尚不清楚.为了研究hCtr1蛋白的C端结构域与铜的结合方式,通过紫外-可见吸收光谱、核磁共振谱和质谱等方法,对C端8肽(C8)与铜离子的结合进行了分析.结果表明,一价铜离子对C8有很高的亲和力(log K=16.6).C8能够结合多个铜离子,其HCH基序中的组氨酸和半胱氨酸残基是铜结合位点,而另一个天冬氨酸残基也可能参与铜结合.进一步研究发现,铜离子能够从C8转移到Atox1.实验数据揭示了铜与hCtr1结合的详情,也有助于理解铜在细胞中的分布.
The intracellular C-terminal domain of human copper transporter hCtr1 is crucial for copper transport and delivery in cells.However,the mechanism of copper acquisition and distribution is not fully understood.The copper binding to hCtr1 was studiedusing a C-terminal peptide(C8)through the methods of UV-vis,NMR and MS spectroscopies.The results show that cuprous ions exhibit high binding affinity to C8(log K=16.6).C8 can bind with multiple copper ions,and the His and Cys residues in the HCH motif are the key binding sites,while an aspartate residue could also be involved in the copper coordination.Further investigation reveals that copper ions can transfer from C8 to the copper chaperone Atox1.These data provide detailed information on the copper binding to hCtr1 and help understand the copperdistributions in cells.
作者
卫浩
许德晨
崔杨
魏开举
袁斯明
刘扬中
WEI Hao;XU Dechen;CUI Yang;WEI Kaiju;YUAN Siming;LIU Yangzhong(Department of Chemistry,University of Science and Technology of China,Hefei 230026,China)
基金
国家自然科学基金(21573213,51503194)
苏州科技发展计划(SYG201624)
江苏省自然科学基金(BK20151238)资助.
