FOXD1 (forkhead box D1) plays a dual role in the establishment of the binocular visual pathways: specification of the ventrotemporal (VT) retina, and patterning of the developing ventral diencephalon where the optic chiasm forms. FOXD1 is also required during kidney development and its inactivation results in failure of nephron progenitor cell differentiation. FOXD1 lentivirus (TET-inducible, Puro) expresses human FOXD1 under the control of the Tet responsive promoter, with puromycin as a selection marker.