Gap junctions in Drosophila:: developmental expression of the entire innexin gene family

Invertebrate cap junctions are composed of proteins called innexins and eight innexin encoding loci hake been identified in the now complete genome sequence of Drosophila melanogaster. The intercellular channels formed by these proteins are multimeric and previous studies have shown that, in a heterologous expression system homo- and hetero-oligomeric channels can form. each combination possessing different gating characteristics. Here we demonstrate that the innexins exhibit complex overlapping expression pattern,, during oogenesis, embryogenesis, imaginal, wing disc development and central nervous system development and show that only certain combinations of innexin oligomerization are possible in vivo. This work forms an essential basis for future studies of innexin interactions in Drosophila and outlines the potential extent of gap-junction involvement in development. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.