Scientific Publications

Sonic hedgehog expression in corticofugal projection neurons directs cortical microcircuit formation.

Publication TypeJournal Article
AuthorsHarwell, CC, Parker PR, Gee SM, Okada A., McConnell SK, Kreitzer AC, and Kriegstein AR
AbstractThe precise connectivity of inputs and outputs is critical for cerebral cortex function; however, the cellular mechanisms that establish these connections are poorly understood. Here, we show that the secreted molecule Sonic Hedgehog (Shh) is involved in synapse formation of a specific cortical circuit. Shh is expressed in layer V corticofugal projection neurons and the Shh receptor, Brother of CDO (Boc), is expressed in local and callosal projection neurons of layer II/III that synapse onto the subcortical projection neurons. Layer V neurons of mice lacking functional Shh exhibit decreased synapses. Conversely, the loss of functional Boc leads to a reduction in the strength of synaptic connections onto layer Vb, but not layer II/III, pyramidal neurons. These results demonstrate that Shh is expressed in postsynaptic target cells while Boc is expressed in a complementary population of presynaptic input neurons, and they function to guide the formation of cortical microcircuitry. VIDEO ABSTRACT:
Year of Publication2012
Date Published (YYYY/MM/DD)2012/03/22
ISSN Number0896-6273