Cells connect and communicate via information superhighway named gap junctions.
Gap junctions are clusters of transmembrane channels that connect the cytoplasms of adjacent cells. These channels permit small metabolites, ions and second messengers to pass from cell to cell. For cells like lens fibers within the interior of the vertebrate eye lens have neither a blood supply nor organelles, thus, lens survival and homeostasis are uniquely dependent on intercellular communication via gap junctions with the cells localized at the lens surface. For cells like bone osteocytes, signals generated by mechanical loading can be transmitted extensively at high speed through gap junction channels. Therefore, gap junctions provide critical means for cell survival and for physiological regulations of cellular functions.