The role of Pax6 in the developing central nervous system

Brain is the most complex organ and believed to contain approximately 10 billion neurons supported by 100 billion glial cells. Due to the recent progress in molecular developmental biology and molecular genetics, the molecular mechanism of operation in controlling the development of central nervous system has been identified and responsible genes have been documented for various deficiencies. The Pax6, a member of the Pax family of transcription factors, is first identified as a master control gene for development of the eyes. We now know that the Pax6 has crucial roles in various developmental processes of the telencephalon including dorsal-ventral and anterior-posterior patterning, specification of neuronal subtypes, neuronal migration and axonal projection. Pax6 deficient mice lack the eyes and nose, and show major defects in cortical lamination and brain size. Recent studies have identified that Pax6 contributes to neurogenesis (production of nerve cells) in the postnatal brain. In this review, we introduce multiple functions of Pax6 in the developing central nervous system and in postnatal neurogenesis.