Identification of a Second Messenger of Crustacean Hyperglycemic Hormone Signaling Pathway in the Kuruma Prawn Marsupenaeus japonicus

To address the signaling pathway of crustacean hyperglycemic hormone (CHH) in the kuruma prawn Marsupenaeus japonicus, we measured the intracellular cAMP and cGMP levels in the hepatopancreas, one of the major target tissues of CHH. Removal of CHH-producing cells by bilateral eyestalk ablation decreased intracellular cGMP levels, while little effect on cAMP was observed in the tissue. Similarly, exposure to recombinant CHH significantly increased the cGMP level of the hepatopancreas in vitro, while little change was observed in cAMP. These results suggest that cGMP, rather than cAMP, mediates the CHH signal in hepatopancreas of M. japonicus.