Fig. 8. Summary model of the Mgn expression and function regarding the specification of GABAergic neurons in the mouse SC. Mgn expression in the VZ/SVZ has an instructive role in the acquisition of GABAergic identity, as determined later on in the mantle zone by the appearance of two specific independent markers for GABAergic cells (Gad65 and Gad67) in the postmitotic neurons. Given the adjacent and non-overlapping expression domains between Mgn and Gad genes, it is likely that the Mgn transcription factor activates downstream gene(s) that, in turn, transactivate the Gad65 and Gad67 promoters.