Glial cells are essential for functionality of the nervous system. Growing evidence underscores the importance of astrocytes; however, analogous astroglia in peripheral organs are poorly understood. Using confocal time-lapse imaging, fate mapping, and mutant genesis in a zebrafish model, Kikel-Coury et al. identify a neural crest-derived glial cell, termed nexus glia, which uses Meteorin signaling via Jak/Stat3 to drive differentiation and to regulate heart rate and rhythm. Nexus glia are labeled with gfap, glast, and glutamine synthetase, markers that typically denote astroglia cells. Further, analysis of single-cell sequencing datasets of human and murine hearts across ages reveals astrocyte-like cells, which the authors confirm through a multispecies approach. They also show that cardiac nexus glia at the outflow tract are critical regulators of both the sympathetic and parasympathetic system. These data establish the crucial role of glia in cardiac homeostasis and provide a description of nexus glia in the peripheral nervous system. The image shows neurons (blue) and astrocyte-like cardiac nexus glia (green) encompassing a zebrafish heart (red).

Image Credit: Nina L. Kikel-Coury