Transcription factor that may function in dorsoventral specification of the forebrain. Required for axon guidance and major tract formation in the developing forebrain. May contribute to the differentiation of the neuroretina, pigmented epithelium and optic stalk. At 9.5 dpc, expressed in the forebrain, through the optic stalk and ending in the proximal portion of the optic vesicle. At 10.5 dpc, expressed in the optic stalk, outer layer of the optic cup, and the primordium of the pigment epithelium. In the pigment epithelium, down-regulated after 11.5 dpc, and expression restricted to the optic stalk and the ventral forebrain. Belongs to the EMX homeobox family.