May determine the distinct specification program of class A neurons in the dorsal part of the spinal cord and suppress specification of class B neurons. Weakly expressed, mainly in non-neural tissues. Restricted to the CNS. At 9.25 and 10.5 dpc, specifically expressed in the dorsal neural tube from the midbrain/hindbrain boundary to the spinal cord. At 10.5 dpc, expressed continuously from the upper rhombic lip to the tail. From 10.5 to 12.5 dpc, located in the most dorsal aspect of the spinal cord, excluding the roof plate, mainly in proliferating progenitor cells; quickly down-regulated in postmitotic neurons. At 11.5 dpc, 3 ventral expression clusters, corresponding to p3, p2 and p0 domains, transiently appear on the lateral margin of the subventricular zone, in addition to dorsal expression. At 14.5 dpc, weakly expressed in cells scattered in the mantle zone. Expression declines after 15.5 dpc. In the 11.5 dpc forebrain, expressed in the ventricular zone of the dorsal thalamus. In the 11.5 to 14.5 dpc hindbrain, dorsally expressed in the upper and lower rhombic lip, in the cerebellar neuroepithelium.