Ligand-induced conformational change within the CD2 ectodomain accompanies receptor clustering: Implication for molecular lattice formation
Ligand-induced conformational change within the CD2 ectodomain accompanies receptor clustering: Implication for molecular lattice formation
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DOI：
10.1006/jmbi.1996.0570
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发表时间：
1996-10-25
影响因子：
5.6
通讯作者：
Reinherz, EL
中科院分区：
文献类型：
--
作者：
Li, J;Smolyar, A;Reinherz, EL
CD2通过其cd58结合膜-远端粘附结构域（D1）介导T细胞与其同源伴侣之间的相互作用，促进T细胞受体（TCR）的触发。由抗cd2r单克隆抗体（mab）定义的新表位表明，在T细胞活化过程中，CD2外畴内的结构发生了变化。在这里，我们将CD2R映射到D1和膜近端胞外结构域（D2）之间的柔性CD2连接区域，并表明该构象位点的暴露与温度和代谢能量无关。CD2和CD58分子在共轭对内的对立细胞上的共连接诱导CD2R并将CD2重新分配到细胞-细胞接触区域。与CD2R（-）分子相反，这些CD2R（+）分子紧密地聚集在T细胞表面。因此，配体介导的D1-D2结构域间角的增加明显暴露了CD2R，促进了CD2分子在集群阵列中的包装，并与CD2介导的粘附和激活事件有关。这种类型的构象改变在涉及表面受体的有序晶格形成中通常是重要的。(C) 1996学术出版社有限公司
CD2 mediates interaction between T cells and their cognate partners through its CD58-binding membrane-distal adhesion domain (D1) facilitating T cell receptor (TCR) triggering. A neoepitope defined by anti-CD2R monoclonal antibodies (mAbs) has suggested structural alteration within the CD2 ectodomain during T cell activation. Here, we map CD2R to the flexible CD2 linker region between D1 and the membrane-proximal extracellular domain (D2) and show that exposure of this conformational site is independent of temperature and metabolic energy. Co-ligation of CD2 and CD58 molecules on opposing cells within a conjugate pair induces CD2R and redistributes CD2 to the region of cell-cell contact. These CD2R(+) molecules, in contrast to the CD2R(-) molecules, are tightly clustered on the T cell surface. Hence, a ligand-mediated increase in the D1-D2 interdomain angle apparently exposes CD2R, facilitates packing of CD2 molecules in a clustered array and is linked to CD2-mediated adhesion and activation events. Conformational alteration of this type may be generally important in ordered lattice formation involving surface receptors. (C) 1996 Academic Press Limited