Regulation of CHH family in eyestalk by A-type allatostatin in the mud crab Scylla paramamosain

Abstract

The eyestalk ganglion is a principal neuroendocrine organ in crustaceans for the synthesis, storage and release of the crustacean hyperglycemic hormone neuropeptide (CHH) family. A-type allatostatin (AST-A) is involved in a variety of physiological functions, although its function in regulating the CHH family in the eyestalk ganglion has not been reported. The present study identified AST-A in the mud crab Scylla paramamosain. AST-A was highly expressed in the ganglia as shown by reverse transcription PCR, while AST-A receptor (AST-AR) was expressed in multiple tissues, such as the eyestalk ganglion. Both in vitro and in vivo experiments revealed that AST-A mature peptide significantly increased mRNA expression of AST-AR, vitellogenesis-inhibiting hormone (VIH), molt-inhibiting hormone (MIH), and crustacean hyperglycemic hormone (CHH). In contrast, RNA interference by injection of AST-AR-dsRNA into crabs significantly reduced the expressions of VIH, MIH, and CHH in the eyestalk ganglion. This study reports for the first time that AST-A might play roles in ovarian development, molting and glucose metabolism in S. paramamosain via regulating CHH family neuropeptides in the eyestalk ganglion.