Transcriptional activator. Induces neural-specific gene expression to act as a key regulator of neural differentiation. From embryonic stage 10, expressed in the Spemann's organizer. During gastrulation, expressed in both the involuting mesoderm and the overlying neuroectoderm. During the neural plate and neural fold stages, expressed in the entire neuroectoderm with expression in discrete regions of the developing nervous system persisting at later stages. Transiently expressed in the pronephros from stages 24-32. In adults, expressed in the kidney and brain. First expressed at embryonic stage 9, with expression increasing at neurula stage and again at the tailbud stage. Expression persists through development to adulthood. By nog, zic1 and zic3. Belongs to the POU transcription factor family. Class-3 subfamily.