通过细胞粘附分子的结合形成的细胞-细胞连接促进了多细胞生物体生长和发育所必需的生理事件。其中,钙黏着蛋白和nectin组织和组装形成粘附连接,从而机械耦合相互作用的细胞。详细了解涉及这些细胞粘附分子的串扰是研究各种发育过程的基础。虽然,钙黏着蛋白和结合蛋白可以通过细胞质衔接分子的相互作用在粘附连接中相互募集。在这里,我们报告了E-cadherin和nectin-4的N端细胞外结构域之间的直接相互作用,如表面等离子体共振(SPR)和基于原子力显微镜(AFM)的单分子力谱(SMFS)所示。使用SPR的动力学研究表明,E-cadherin和nectin-4的胞外域之间的结合,KD为3.7±0.7µM,KD为5.4±0.2µM(倒数实验)。基于AFM的SMFS实验还支持E-cadherin和nectin-4的胞外域之间的相互作用,koff值为31.48±1.53s-1,复合物的寿命为0.036±0.0026s。因此,我们提出了由E-cadherin和nectin-4介导的细胞粘附机制,从早期发育过程中这两种蛋白质的表达模式可以看出,这在早期胚胎发生中具有功能意义。
Cell-cell junctions formed by the association of cell adhesion molecules facilitate physiological events necessary for growth and development of multicellular organisms. Among them, cadherins and nectins organize and assemble to form adherens junction, which thereby mechanically couples interacting cells. A detailed understanding of the crosstalk involving these cell adhesion molecules is fundamental to the study of the various developmental processes. Although, cadherins and nectins can recruit each other in the adherens junction through an interplay of cytoplasmic adaptor molecules, here, we report a direct interaction between N-terminal extracellular domains of E-
cadherin and nectin-4 as demonstrated by surface plasmon resonance (SPR) and Atomic Force Microscopy (AFM)-based single molecule force spectroscopy (SMFS). Kinetic studies using SPR demonstrate the binding between the ectodomains of E-
cadherin and nectin-4 with a KD of 3.7 ± 0.7 µM and KD of 5.4 ± 0.2 µM (reciprocal experiment). AFM-based SMFS experiments also support interaction between the ectodomains of E-
cadherin and nectin-4 with the koff value of 31.48 ± 1.53 s-1 and the lifetime of the complex of 0.036 ± 0.0026 s. We thus propose a cell adhesion mechanism mediated by E-
cadherin and nectin-4, which can have functional significance in early embryogenesis as evident from the expression pattern of both the proteins during early development.