Gap junction channels: new roles in disease.

The importance of intercellular communication to complex cellular processes such as development, differentiation, growth, propagation of electrical impulses and diffusional feeding has long been appreciated. The realization that intercellular communication is mediated by gap junction channels, which are in turn comprised of a diverse family of proteins called the connexins, has provided new tools and avenues for studying the role of intercellular communication in these important cellular processes. The identification of different connexin isoforms has not only enabled the development of specific reagents to study connexin expression patterns, but has also allowed the functional properties of the different connexin isoforms and how they interact with each other, to be explored. Increasingly, the knowledge gained from studying connexin diversity is being used to investigate the role played by gap junction channels in a number of diseases. In this article we highlight selected cases where gap junction channels have been shown or are believed to be directly involved in the disease process.