Meeting Abstract
Peptides are important modulators of neural circuit activity. In central pattern generator (CPG)-effector systems, peptides allow for flexibility in rhythmic motor output. In the lobster, Homarus americanus, the cardiac neuromuscular system, which consists of the cardiac ganglion (CG) and cardiac muscle (CM), controls the rhythmic motor output of the heart. This system is subject to modulation by both intrinsically and extrinsically-released peptides. Extrinsic peptides can be locally released from input fibers projecting to the CG from somata located elsewhere in the nervous system or can be delivered to CG and/or CM hormonally via the hemolymph. To investigate hormonal signaling in the cardiac neuromuscular system, we generated CG- and CM-specific transcriptomes, which were mined for peptide receptor-encoding sequences, specifically those for peptides known to be present in the sinus gland and/or pericardial organ, two neuroendocrine organs. Receptors for seven peptide families were identified, with some receptors restricted either to the CG (crustacean cardioactive peptide, red pigment concentrating hormone, and tachykinin-related peptide) or CM (pigment dispersing hormone), and others found in both tissues (allatostatin-C, myosuppressin, and proctolin). These data suggest that some peptides may have different sites of action within the cardiac neuromuscular system. Supported by: NSF (IOS-1353023, IOS-1354567, OCE-1459235), NIH (8P20GM103423-12), Cades Fdn., UHManoa’s Undergrad Res. Opp. Prog., APS Undergrad Res. Fellowship, Doherty Fdn./Bowdoin Coll.
