ABSTRACT
This chapter reviews the information available concerning some of the cloned gastrointestinal neuropeptides in terms of their chromosomal localization, gene and messenger RNA organization and the structure of their precursor protein. The enhancer frequently consists of repeats in the nucleotide structure which occasionally enhance weakly by them, but usually more than one enhancer motif is needed for full enhancement. The enhancers show both species and tissue-specificity, but viral enhancers seem less discriminating and work in most combinations with foreign genes. Nerve growth factor enhances the outgrowth of neurite-like processes in cultured human pheocromocytoma cells and in chromaffin cells dissociated from normal human adrenal glands and increases vasoactive intestinal peptide-like immunoreactivity (VIP-LI) production. Ascorbic acid increased levels of VIP-LI in the medium from murine neuroblastoma cells and the addition of forskolin potentiated this effect. The Neuropeptide Y precursor protein consists of 97 and 98 amino acids, respectively, in man and rat.
