ABSTRACT
This chapter provides the essential and findings on primary structures and several biological functions of neuropeptides, peptide hormones, and their receptors in of ascidians. Ascidians, invertebrate deuterostome marine animals, belong to the same phylum to vertebrates, chordata, and subphylum tunicate or urocho-data. Tachykinin are vertebrate multi-functional brain peptides regulating smooth muscle contraction, vasodilation, nociception, inflammation, neurodegeneration, and neuroprotection in a neuropeptidergic or endocrine fashion. Neurotensin is a vertebrate brain peptide involved in dopamine transmission, pituitary hormone secretion, hypothermia, and analgesia. Galanin and galanin-like peptide are vertebrate brain/gut peptides involved in reproduction and feeding in vertebrates. In conclusion, a combination of MS-based peptidomic analysis and database-referencing of the resultant sequence is the most reliable and efficient methods for characterization of neuropeptides and peptide hormones.
