FIGURE 3.

Clonal production and organization of neocortical interneurons. Radial glial progenitor cells divide asymmetrically at the ventricular zone surface to self renewand to simultaneously produce differentiating interneurons or intermediate progenitor cells whichthen divide symmetrically in the subventricular zone to produce differentiating interneurons. The progeny of the same radial glial progenitor cell initially migrate along the mother radial glial cell and form radially aligned clonal clusters. As development proceeds, the early-born cells progressively move away from the ventricular zone, acquire the characteristic morphological and biophysical features of differentiating interneurons, and migrate tangentially towards the neocortex. After arriving at their destination in the neocortex, inhibitory interneuron clones do not randomly disperse, but form spatially organized vertical or horizontal clusters. Ncx, neocortex; LGE, lateral ganglionic eminence; MGE, medial ganglionic eminence; PoA, preoptic area.