Herein, we provide evidence that the Zfhx1b (Sip1, Zeb2) zinc-finger homeobox transcription factor is required to repress Nkx2-1 in the generation of cortical interneurons. In its absence, we find a decrease in cortical interneurons concomitant with increased striatal nNOS/NPY/Sst GABAergic interneurons. We provide evidence that expression of the cMaf transcription factor is a highly specific marker of the cortical interneuron lineage, and discovered that its expression is lost in Zfhx1b mutants.
