HepaCAM shapes astrocyte territories, stabilizes gap-junction coupling, and influences neuronal excitability

How astrocytes form non-overlapping territories within synaptic neuropil is not understood. In this issue of Neuron, Baldwin et al. (2021) report that the cell adhesion molecule hepaCAM shapes murine astrocyte territories and that hepaCAM loss impairs gap-junction cell coupling and the balance between synaptic excitation and inhibition.