Meeting Abstract
The molecular components of peptidergic signaling systems in nervous systems include both neuropeptides and peptide receptors. In the lobster, Homarus americanus, numerous neuropeptides have been identified and characterized. In contrast, nothing is known about the identity of neuropeptide receptors in this species. Here, known peptide receptors, primarily ones from the fruit fly, Drosophila melanogaster, were used to mine a H. americanus neural transcriptome for sequences encoding homologous proteins. Via this strategy, over 40 putative receptor-encoding transcripts were identified. The proteins deduced from these receptors include putative adipokinetic hormone-corazonin-like peptide, allatostatin A, allatostatin C (AST-C), bursicon, CCHamide, corazonin, crustacean cardioactive peptide, diuretic hormone 31, diuretic hormone 44, ecdysis-triggering hormone, FLRFamide, insulin-like peptide, leucokinin, myosuppressin, neuropeptide F, pigment dispersing hormone, proctolin, pyrokinin, red pigment concentrating hormone, SIFamide, sulfakinin and tachykinin-related peptide receptors. For many peptide groups, multiple receptor subtypes appear to exist in the lobster. For example, three distinct proteins showing homology to known AST-C receptors were discovered. Structural analysis of the full-length proteins showed the majority of them to possess complements of structural motifs consistent with their proposed function as peptide receptors, e.g. seven membrane spanning regions, and, in some cases, hormone-binding domains.
