Gap junctions mediate cellular communication and homeostasis by controlling the intercellular exchange of small and hydrophilic molecules and ions. Gap junction channels are formed by the docking of 2 hemichannels of adjacent cells, which in turn are composed of 6 connexin subunits. Connexin proteins as such can also control the cellular life cycle independent of their channel activities. This has been most demonstrated in the context of cell growth and cell death. Different mechanisms are involved mainly related to direct interaction with cell growth or cell death regulators, but also implying effects on the expression of cell growth and cell death regulators. The present paper focuses on these atypical roles of connexin proteins.

间隙连接通过控制小而亲水的分子和离子的细胞间交换来介导细胞通讯和体内平衡。间隙连接通道是由相邻细胞的2个半通道对接形成的，相邻细胞又由6个连接蛋白亚基组成。这样的连接蛋白也可以独立于其通道活性来控制细胞生命周期。这在细胞生长和细胞死亡的背景下得到了最充分的证明。涉及的不同机制主要涉及与细胞生长或细胞死亡调节剂的直接相互作用，但也暗示对细胞生长和细胞死亡调节剂表达的影响。本文重点介绍连接蛋白的这些非典型作用。