Dorsal neural-tube nuclear protein is a 398 amino acid nuclear protein. DNTNP is thought to play an important role in neural development by specifying dorsal cell fates within the neural tube. Widely expressed in the dorsal neural tube, DNTNP is most highly expressed in the dorsal regions of the midbrain, the hindbrain, the diencephalon, and the spinal neural tube and is expressed at lower levels in the branchial arches, the telencephalon, the heart, and somites of developing embryos. DNTNP is encoded by a gene located on chromosome 4 which contains many genes including the Huntingtin gene, which is found to encode an expanded glutamine tract in cases of Huntington's disease.