N-Terminal Deletion Effects of Human Survivin on Dimerization and Binding to Smac/DIABLO in Vitro
详细信息 查看全文
- 作者：Yang Gao ; Huafei Zhang ; Min Zhang ; Haihong Zhang ; Xianghui Yu ; Wei Kong ; Xiao Zha ; Yuqing Wu
- 刊名：Journal of Physical Chemistry B
- 出版年：2010
- 出版时间：December 2, 2010
- 年：2010
- 卷：114
- 期：47
- 页码：15656-15662
- 全文大小：239K
- 年卷期：v.114,no.47(December 2, 2010)
- ISSN：1520-5207
文摘
Survivin, as an apoptosis suppressor, exists as a homodimer interfacing at the N-terminal portion (residues 6−13) of its baculovirus IAP repeat (BIR) domain and a linker segment (residues 89−102). Here we expressed full-length human Survivin (SurF) and a series of its mutants, SurΔN7, SurΔN13, and SurΔN18 with significant truncations of the N-terminus, all of which could still dimerize in solution. Single-molecule force spectroscopy (SMFS) was used to quantitate the unbinding forces of full-length and the mutant homodimers and revealed that the N-terminal residues up to Arg18 were not essential for dimerization. Meanwhile, the binding of SurΔN7 to Smac/DIABLO determined by ELISA was as efficient as the wild-type, but that of SurΔN13 was significantly reduced, and that of SurΔN18 was completely lost. Together, these findings provide direct evidence that the N-terminal sequence of Survivin is not critical for dimer formation but may contribute to correct folding and function of BIR.