Department of Genetics and Development, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
Int Rev Cell Mol Biol. 2012;295:63-108. doi: 10.1016/B978-0-12-394306-4.00008-3.
Homeostasis of adherens junctions is achieved through complex regulatory mechanisms. The junctions are highly dynamic in contact establishment, in remodeling events during development, and during processes involving a loss of adhesion like epithelial-mesenchyme transition. It appeared recently that they are also dynamically renewed in mature, steady-state adhesions. Indeed, maintenance of a steady state must be integrated into a tight control of force equilibrium between a cell and its neighbors. Therefore, it appears that E-cadherin dynamics allows to respond constantly to various biochemical and mechanical stimuli and to regulate the movement and shape of junctions in active remodeling processes. E-cadherin dynamics is mediated through several mechanisms (diffusion, trafficking) in function of the biological system. In mature junctions, membrane E-cadherin is quickly renewed by endocytosis in many cell types. E-cadherin endocytosis shows a complex regulation, depending on small G proteins, ubiquitination, cleavage events, actomyosin cytoskeleton, and other trans molecules in adherens junctions. It is modulated by growth factor stimulations and physical factors. Consequently, E-cadherin endocytosis tightly controls a number of functional processes: cell movements, junction maintenance, cell sorting, and polarity. Misregulated E-cadherin endocytosis is involved in many diseases, from cancerous processes to organogenesis defects.
黏附连接的稳态是通过复杂的调节机制实现的。在接触建立、发育过程中的重塑事件以及涉及黏附丧失的过程（如上皮-间充质转化）中，连接非常动态。最近似乎表明它们在成熟的稳定黏附中也在动态更新。实际上，维持稳定状态必须整合到细胞与其相邻细胞之间的力平衡的严格控制中。因此，似乎 E-钙黏蛋白动力学允许对各种生化和机械刺激做出持续反应，并调节在主动重塑过程中连接的运动和形状。E-钙黏蛋白动力学通过几种机制（扩散、运输）在生物系统中发挥作用。在成熟的连接中，膜 E-钙黏蛋白在许多细胞类型中通过内吞作用快速更新。E-钙黏蛋白内吞作用的调节非常复杂，取决于小 G 蛋白、泛素化、切割事件、肌动球蛋白细胞骨架和黏附连接中的其他跨分子。它受到生长因子刺激和物理因素的调节。因此，E-钙黏蛋白内吞作用紧密控制着许多功能过程：细胞运动、连接维持、细胞分选和极性。E-钙黏蛋白内吞作用失调与许多疾病有关，从癌症过程到器官发生缺陷。
