one example is semaphorins. the semaphorins are able to exert their repulsive forccecs upon interneurons because interneurons express neuropilins and plexin coreceptors, both of which recognize semaphorins that are expressed within the LGE. sema3a and sema3f reulate migratory capacity of GABAergic interneurons toward the cortex. chondroitin-4-sulfate acts in concert with sema3a to repel migrating neurongs within the LGE \cite{Kelsom_2013}
slit1 is a second chemorepellant whose expression is found in the ventricular zone and subentricular zone of the GEs and in the embryonic POA. slit1 is abel to exert its chemorepulsive effects due to the expression of of its receptor Roudabout (robo1) on migrating cortical interneurons. interneurons are repelled from their sites of origins in the GEs thanks to slit and robo. \cite{Kelsom_2013}