The expanding roles of adhesion GPCRs in neural circuit assembly

Bidirectional trans-synaptic signaling directs synapse formation and neural circuit assembly. Increasing evidence supports that several subfamilies of adhesion G protein-coupled receptors (aGPCRs) control important mechanistic aspects of synapse assembly and neural circuit wiring by combining trans-synaptic adhesion with G protein-coupled receptor signaling. These subfamilies include Latrophilins (ADGRL), CELSRs (cadherin EGF LAG 7-transmembrane receptors/ADGRC), and BAIs (brain angiogenesis inhibitors/ADGRB). Recently, aGPCRs have been linked to neurological disorders, further emphasizing the important roles of these receptors for proper neurological functions. Here, we discuss our current understanding of the functions of several aGPCRs in synaptic circuits and their links to neurological and neurodevelopmental disorders.