Cortical interneurons derived from Nkx2.1-expressing precursors. A–O, Coexpression of GFP with CB, CR, PV, NPY, and SST. Arrows indicate interneurons coexpressing GFP. Arrowheads point to interneurons that are negative for GFP. P, The contribution of Nkx2.1-expressing precursors to interneuron populations expressing CB, CR, PV, NPY, or SST in the motor and somatosensory cortex. The extent of colocalization between GFP and each of the five markers was quantified, and the data are presented as percentage of the total number of cells expressing each of the five markers. Q, The contribution of Nkx2.1-expressing precursors to interneuron populations in the upper and lower layers of the motor and somatosensory cortex. R, The number of Nkx2.1-derived cells coexpressing GFP and one of the markers CB, CR, PV, NPY, or SST are presented as a percentage of the total number of GFP+ cells. Scale bar: (in A) A–O, 20 μm.