Reciprocal repulsions instruct the precise assembly of parallel hippocampal networks

Keeping brain development untangled Brain circuits established during development can be overlapping or parallel as needed. Pederick et al. analyzed how parallel circuits in the mouse medial and lateral hippocampus develop without getting tangled up. Regulated expression of the cell surface molecules teneurin-3 (Ten3) and latrophilin-2 (Lphn2) keeps confusion at bay. Together, these factors act as a membrane-bound ligand-receptor pair with repulsive outcomes, and they are able to destabilize a nascent but incorrect axon-target interaction. Individually, they each mediate homophilic attraction as axons search for their favored targets. Science, abg1774, this issue p. 1068