Structural characterization of the DC-SIGN-Lewis(X) complex.
Structural characterization of the DC-SIGN-Lewis(X) complex.
复制标题
DOI：
10.1021/bi5005014
复制
发表时间：
2014-09-09
期刊：
影响因子：
2.9
通讯作者：
Prestegard JH
中科院分区：
文献类型：
--
作者：
Pederson K;Mitchell DA;Prestegard JH
树突状细胞特异性细胞内粘附分子3抓取非整合素（DC-SIGN）是一种高度表达于抗原呈递树突状细胞表面的C型凝集素。DC-SIGN通过与致病性入侵者上的高甘露糖残基或其他免疫细胞膜上的岩藻糖基化残基结合，介导树突状细胞、病原体和各种上皮细胞、髓样细胞和内皮细胞之间的相互作用。虽然这些相互作用通常是有益的，但它们也可能导致疾病。因此，结合几何形状的结构表征作为构建可介导异常免疫应答作用的模拟物的基础是令人感兴趣的。在这里，我们报告的DC-SIGN碳水化合物识别结构域（CRD）与一个共同的岩藻糖基化的实体，LewisX三糖（LeX），使用NMR方法的相互作用的结构特征。通过2D NMR监测的单体DC-SIGN CRD与LeX的滴定揭示了1H-15 N杂原子单量子相干（HSQC）光谱中DC-SIGN交叉峰位置的显著扰动，并鉴定了结合位点附近的残基。此外，饱和转移差（STD）和转移核Overhauser效应（trNOE）NMR实验，使用DC-SIGN的四聚体形式，确定了LeX配体的结合表位和结合构象。来自这些多个实验的约束用于生成LeX与DC-SIGN CRD结合的模型。基于trNOE数据和STD累积曲线的基于模型的模拟拟合的模型的排名表明与先前晶体结构中所见的构象不同。新的构象提供了深入了解如何结合LewisX和甘露糖终止的α-甘露糖之间的差异可能会传播。
Dendritic cell-specific intracellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN) is a C-type lectin highly expressed on the surface of antigen-presenting dendritic cells. DC-SIGN mediates interactions among dendritic cells, pathogens, and a variety of epithelia, myeloid cells, and endothelia by binding to high mannose residues on pathogenic invaders or fucosylated residues on the membranes of other immune cells. Although these interactions are normally beneficial, they can also contribute to disease. The structural characterization of binding geometries is therefore of interest as a basis for the construction of mimetics that can mediate the effects of abnormal immune response. Here, we report the structural characteristics of the interaction of the DC-SIGN carbohydrate recognition domain (CRD) with a common fucosylated entity, the LewisX trisaccharide (LeX), using NMR methods. Titration of the monomeric DC-SIGN CRD with LeX monitored by 2D NMR revealed significant perturbations of DC-SIGN cross-peak positions in 1H–15N heteronuclear single quantum coherence (HSQC) spectra and identified residues near the binding site. Additionally, saturation transfer difference (STD) and transferred nuclear Overhauser effect (trNOE) NMR experiments, using a tetrameric form of DC-SIGN, identified binding epitopes and bound conformations of the LeX ligand. The restraints derived from these multiple experiments were used to generate models for the binding of LeX to the DC-SIGN CRD. Ranking of the models based on the fit of model-based simulations of the trNOE data and STD buildup curves suggested conformations distinct from those seen in previous crystal structures. The new conformations offer insight into how differences between binding of LewisX and mannose-terminated saccharides may be propagated.
登录
查看更多内容
影响因子：
4.9
作者：
Ciobanu, Mihai;Huang, Kuo-Ting;Winssinger, Nicolas
通讯作者：
Winssinger, Nicolas
影响因子：
15.3
作者：
Geijtenbeek, TBH;van Vliet, SJ;Koppel, EA;Sanchez-Hernandez, M;Vandenbroucke-Grauls, CMJE;Appelmelk, B;van Kooyk, Y
通讯作者：
van Kooyk, Y
影响因子：
15
作者：
Becer, C. Remzi;Gibson, Matthew I.;Geng, Jin;Ilyas, Rebecca;Wallis, Russell;Mitchell, Daniel A.;Haddleton, David M.
通讯作者：
Haddleton, David M.
影响因子：
56.9
作者：
Feinberg, H;Mitchell, DA;Weis, WI
通讯作者：
Weis, WI
影响因子：
5.4
作者：
Engering, AJ;Cella, M;Pieters, J
通讯作者：
Pieters, J