SPR and HDXMS Analysis of Interactions between Complement Component 3 and Thrombomodulin
SPR and HDXMS Analysis of Interactions between Complement Component 3 and Thrombomodulin
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补体成分 3 与血栓调节蛋白之间相互作用的 SPR 和 HDXMS 分析
DOI：
10.1016/j.bpj.2019.11.387
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发表时间：
2020
影响因子：
3.4
通讯作者：
Giler, Jose
中科院分区：
文献类型：
--
作者：
Koeppe, Julia R.;Giler, Jose
我们已经使用表面等离子体共振（SPR）和氢/氘交换质谱（HDXMS）来研究血栓调节蛋白和补体成分3（C3）之间的相互作用。补体成分3（C3）位于三种不同补体激活途径（经典、凝集素和替代）的连接处。激活C3 b是先天免疫应答中的关键步骤，其允许形成最终参与病原体清除的重要多蛋白复合物。当失调时，补体可导致炎性疾病和自身免疫性疾病。C3 b的几种调节蛋白是已知的，但这些蛋白之间相互作用的分子细节尚未阐明。血栓调节蛋白（TM），特别是其N-末端凝集素样结构域（TMD 1），已被鉴定为通过与C3或C3 b相互作用的可能的补体调节剂，并且也可能需要已知的调节剂CFH。使用SPR，我们看到C3或C3 b可以结合到涂有TMD 1的表面上，并且正在进行全面的动力学研究。使用HDXMS，我们看到TMD 1与C3 b相互作用，与C3的相互作用较小。TMD 1倾向于使C3 b更容易进行氘交换，而C3在TMD 1存在下倾向于不太容易进行氘交换。这种差异表明TMD 1在调节补体途径中的关键步骤中可能起作用。接下来我们将研究CFH在这些相互作用中的作用。
We have used surface plasmon resonance (SPR) and hydrogen/deuterium exchange mass spectrometry (HDXMS) to study the interaction between thrombomodulin and complement component 3 (C3) Complement component 3 (C3) is at the junction of three different complement activation pathways (classical, lectin, and alternative). Activation to C3b is a key step in the innate immune response that allows for the formation of important multi-protein complexes that ultimately participate in pathogen clearance. When misregulated, complement can lead to inflammatory disease and autoimmune disorders. Several regulatory proteins for C3b are known, but the molecular details of interactions between these proteins have not yet been elucidated. Thrombomodulin (TM), and specifically its N-terminal lectin-like domain (TMD1), has been identified as a possible regulator of complement through interactions with C3 or C3b, and the known regulator CFH may also be required. Using SPR, we see that C3 or C3b can bind to a surface coated with TMD1, and full kinetic studies are underway. Using HDXMS, we see that TMD1 interacts with C3b, and there is a lesser interaction with C3. TMD1 tends to make C3b more accessible to deuterium exchange, while C3 tends to be less accessible to deuterium exchange in the presence of TMD1. This difference suggests a possible role for TMD1 in regulating a key step in the complement pathway. We will next investigate the role of CFH in these interactions.