Long-term editing of brain circuits in mice using an engineered electrical synapse

Electrical signaling across distinct populations of brain cells underpins cognitive and emotional function; however, approaches that selectively regulate electrical signaling between two cellular components of a mammalian neural circuit remain sparse. Here, we engineered an electrical synapse composed of two connexin proteins found inMorone americana(white perch fish) – connexin34.7 and connexin35 – to accomplish mammalian circuit modulation. By exploiting protein mutagenesis, devising a newin vitrosystem for assaying connexin hemichannel docking, and performing computational modeling of hemichannel interactions, we uncovered a structural motif that contributes to electrical synapse formation. Targeting these motifs, we designed connexin34.7 and connexin35 hemichannels that dock with each other to form an electrical synapse, but not with other major connexins expressed in the mammalian central nervous system. We validated this electrical synapsein vivousingC. elegansand mice, demonstrating that it can strengthen communication across neural circuits composed of pairs of distinct cell types and modify behavior accordingly. Thus, we establish ‘<underline>L</underline>ong-term<underline>in</underline>tegration of<underline>C</underline>ircuits using conne<underline>x</underline>ins’ (LinCx) for precision circuit-editing in mammals.