Meeting Abstract

15.4  Monday, Jan. 4  Distribution of allatostatin C-like immunoreactivity in the central nervous system of the copepod crustacean Calanus finmarchicus WILSON, Caroline H.*; CHRISTIE, Andrew E.; Denison University, Granville, OH ; Mount Desert Island Biological Laboratory, Salisbury Cove, ME wilsonc@denison.edu

PICSF- or Manduca sexta– C-type Allatostatins(AST-C) are a family of neuropeptides known to regulate juvenile hormone in insects. AST-C peptide isoforms are conserved within pancrustacea, but it has not yet been characterized in a primitive crustacean such as the copeped. One species of copepod, Calanus finmarchicus, is abundant in the North Atlantic and is a major contributor to the summer zooplankton biomass, thus making it an important component of the marine food web. In order to assess whether copepods contain AST-C-like peptides, we used a pQIRYHQCYFNPISCF antigen to investigate whether AST-C was present in the nervous system of C. finmarchicus. Our results indicate AST-C is present in the neurons in the protocerebrum of the brain, several peripheral ganglia associated with feeding appendages, and in the ganglia controlling the swimming feet. Some of the AST-C containing neurons extend neurites into the periphery innervating muscles such as the ventral longitudinal muscles and extensors and flexors of the swimming feet. This labeling pattern appeared to be consistent across sexes and developmental stages, with only the youngest stages examined showing a difference in the swimming leg neurons. We also complimented the AST-C immunolabeling with other proteins (acetylated alpha tubulin, Allatostatin-A, and tachykinin-related peptide) to place our findings into context with the entire nervous system and other peptidergic neurons. Our results indicate that AST-C antibodies label a unique set of neurons in the copepod from other antigens and that several of these neurons are associated with feeding appendages.