Recent findings in evolution and function of insect innexins

The past decade has seen significant advances in the field of innexin biology, particularly in the model invertebrate organisms, the nematode Caenorhabditis elegans and the fly Drosophila melanogaster. However, advances in genomics and functional techniques during this same period are ushering in a period of comparative innexin biology. Insects are the most diverse metazoan taxa in terms of species number, as well as in developmental, physiological, and morphological processes. Combined with genomics data, the study of innexins should rapidly advance. In this review, we consider the current state of knowledge regarding innexins in insects, focusing on innexin diversity, both evolutionary and functional. We also consider an unusual set of innexins, known as vinnexins, that have been isolated from mutualistic viruses of some parasitoid wasps. We conclude with a call to study insect innexins from a broader, evolutionary perspective. Knowledge derived from such comparative studies will offer significant insight into developmental and evolutionary physiology, as well as specific functional processes in a taxon that has huge biomedical and ecological impact on humans.