Dendrite glia interactions: lessons from the C. elegans amphid sense organ.

Glia are critical components of the nervous system, regulating the development and function of associated neurons. While much attention has focused on interactions between glia and axons, growing evidence highlights the importance of critical and evolutionarily conserved interactions between glia and dendrites, particularly in organisms with simple nervous systems such as Caenorhabditis elegans. Glia critically support the structure and function of associated dendrites through regulation of the ionic microenvironment, uptake of extracellular vesicles and fragments, and signaling regulation downstream of direct glial sensation of environmental stimuli in the major C. elegans sense organs. Glia also elicit beneficial responses upon defects in dendrite structure, stress, aging, and perhaps exposure to pathogens. Emerging themes are that a single glial cell can regulate distinct interacting dendrites differently and that neurons can communicate extra-synaptically via a shared interacting glial cell.