Gap junctions in nematodes

Gap junctions (GJ) are one of the most common forms of intercellular communication. They are considered to serve a similar function in all multicellular animals (Metazoa) and provide a general route for intercellular interactions in various tissues and cell types. GJ are composed of proteins that form a channel connecting the cytoplasm of adjacent cells. Two unrelated protein families are involved in this function: connexins, which are found only in chordates, and pannexins/innexins, which are present in both chordate and invertebrate genomes. Nematodes are recognised as extremely useful model organisms for various areas of biological studies with complete genomes sequenced in many species and the free-living nematode, Caenorhabditis elegans, is one of the best studied model organisms. Genomes of different nematode species contain 12-25 pannexins/innexins. We compared nematode GJ proteins with GJ proteins of other species, reviewed their expression patterns and their role in several biological functions.