Feng Jianwen, Garrity David, Call Matthew E, Moffett Howell, Wucherpfennig Kai W
Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115, USA.
Immunity. 2005 Apr;22(4):427-38. doi: 10.1016/j.immuni.2005.02.005.
Activating receptors in cells of hematopoetic origin include members of two unrelated protein families, the immunoglobulin (Ig) and C type lectins, which differ even in the orientation of the transmembrane (TM) domains. We examined assembly of four receptors with diverse function: the NK receptors KIR2DS and NKG2C/CD94, the Fc receptor for IgA, and the GPVI collagen receptor. For each of the four different receptors studied here, assembly results in the formation of a three-helix interface in the membrane involving two acidic TM residues from the signaling dimer and a basic TM residue from the ligand recognition module, an arrangement remarkably similar to the T cell receptor (TCR)-CD3 complex. The fact that the TM domains of Ig family and C type lectins adopt opposite orientations proves that these receptor families independently evolved toward the same structural arrangement of the interacting TM helices. This assembly mechanism is thus widely utilized by receptors in cells of hematopoetic origin.
在造血起源细胞中激活的受体包括两个不相关蛋白质家族的成员，即免疫球蛋白（Ig）和C型凝集素，它们甚至在跨膜（TM）结构域的方向上也有所不同。我们研究了四种具有不同功能的受体的组装：NK受体KIR2DS和NKG2C/CD94、IgA的Fc受体以及GPVI胶原受体。对于此处研究的四种不同受体中的每一种，组装都会在膜中形成一个三螺旋界面，该界面涉及来自信号二聚体的两个酸性TM残基和来自配体识别模块的一个碱性TM残基，这种排列与T细胞受体（TCR）-CD3复合物非常相似。Ig家族和C型凝集素的TM结构域采用相反方向这一事实证明，这些受体家族独立进化为相互作用的TM螺旋的相同结构排列。因此，这种组装机制被造血起源细胞中的受体广泛利用。
