Annexin A2/P11 interaction: New insights into annexin A2 tetramer structure by chemical crosslinking, high-resolution mass spectrometry, and computational modeling
Annexin A2/P11 interaction: New insights into annexin A2 tetramer structure by chemical crosslinking, high-resolution mass spectrometry, and computational modeling
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DOI：
10.1002/prot.21445
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发表时间：
2007-11-01
影响因子：
2.9
通讯作者：
Sinz, Andrea
中科院分区：
文献类型：
--
作者：
Schulz, Daniela M.;Kalkhof, Stefan;Sinz, Andrea
在过去的几年中，通过化学交联和质谱法对蛋白质和蛋白质复合物进行结构分析越来越受欢迎。通过这种方法，我们研究了膜联蛋白 A2 和 p11 之间复合物的四级结构，该复合物参与许多细胞过程。尽管对于两个相互作用伙伴以及两个 p11 亚基和两个膜联蛋白 A2 N 端肽之间的复合物都有高分辨率数据，但完整的膜联蛋白 A2/p11 异四聚体的结构尚未以高分辨率解析。因此，生物相关的膜结合膜联蛋白 A2/p11 复合物的四级结构仍在讨论中，而异四聚体或异八聚体的存在是主流观点。通过采用化学交联结合高分辨率质谱，我们进一步了解了膜联蛋白 A2/p11 异四聚体的空间组织。此外，串联质谱法可作为交联氨基酸残基的精确定位和交联产物归属确认的工具。根据交联数据的距离约束，我们通过与 Rosetta 的计算对接得出了膜联蛋白 A2/p11 异四聚体的结构模型。我们提出了膜联蛋白 A2/p11 复合物的八聚体模型，该模型发挥膜联蛋白 A2 的功能。膜联蛋白 A2/p11 八聚体的拟议结构与迄今为止建议的模型不同，并为膜联蛋白 A2/p11 相互作用提供了新的线索。
During the past few years, the structural analysis of proteins and protein complexes by chemical crosslinking and mass spectrometry has enjoyed increasing popularity. With this approach we have investigated the quaternary structure of the complex between annexin A2 and p11, which is involved in numerous cellular processes. Although high-resolution data are available for both interaction partners as well as for the complex between two p11 subunits and two annexin A2 N-terminal peptides, the structure of the complete annexin A2/p11 heterotetramer has not yet been solved at high resolution. Thus, the quaternary structure of the biologically relevant, membrane-bound annexin A2/p11 complex is still under discussion, while the existence of a heterotetramer or a heterooctamer is the prevailing opinion. We gained further insight into the spatial organization of the annexin A2/p11 heterotetramer by employing chemical crosslinking combined with high-resolution mass spectrometry. Furthermore, tandem mass spectrometry served as a tool for an exact localization of crosslinked amino acid residues and for a confirmation of crosslinked product assignment. On the basis of distance constraints from the crosslinking data we derived structural models of the annexin A2/p11 heterotetramer by computational docking with Rosetta. We propose an octameric model for the annexin A2/p11 complex, which exerts annexin A2 function. The proposed structure of the annexin A2/p11 octamer differs from so far suggested models and sheds new light into annexin A2/p11 interaction.