ABSTRACT
Neuropeptides represent an important class of signal molecules involved in diverse aspects of metazoan development and homeostasis (Yamanaka et al. 2008). Neuropeptides are generated in neurons of the brain and peripheral nerve system by enzymatic prohormone cleavage. Present in both cnidarians and bilaterians, they represent an ancient and widespread mode of neurohumoral communication (Jekely 2013). Neuropeptides are essential brain peptides and modulate animal physiology by affecting the activity of almost every neural circuit (Hummon et al. 2006). As signaling molecules they commonly act through G-protein coupled receptors (GPCRs) and affect the levels of cyclic nucleotides (e.g., c-AMP and c-GMP) and Ca2+ in target tissues (Mykles et al. 2010). The G-protein coupled receptor family is characterized by seven transmembrane domain proteins and together with the respective peptide ligands they play an important role in nerve transmission and sensory perception, locomotion, development and reproduction, metabolism, and neuromodulation (Bendena et al. 2012). Clustering of neuropeptide preprohormones and
Animal Ecology I, BayCEER, University of Bayreuth, Universitätsstraße 30, 95440 Bayreuth, Germany.
