Dual roles of crustacean female sex hormone during juvenile stage in the kuruma prawnMarsupenaeus japonicus

Abstract

ABSTRACTThe crustacean female sex hormone (CFSH) has been identified as a female-specific hormone that plays a crucial role in female phenotype developments in the blue crabCallinectes sapidus. To date, its homologous genes have been reported in various decapod species. Additionally, unlike the blue crab, several species have two different CFSH subtypes. The kuruma prawnMarsupenaeus japonicusis a representative example species of this phenomenon, having two CFSH subtypes identified from the eyestalk (MajCFSH) and ovary (MajCFSH-ov). Eyestalk-type MajCFSH is expressed predominantly in the eyestalk at the same level in both sexes, indicating no female-specificity. Here, we conducted gene knockdown analysis of eyestalk-type MajCFSH using sexually immature juveniles of kuruma prawn (average body length: ∼10 mm) to elucidate its physiological functions. As a result, MajCFSH-knockdown did not affect the development of sex-specific characteristics such as external reproductive organs, while it induced apparent growth suppression in male juveniles, implying that MajCFSH may play a male-specific juvenile growth role. Moreover, MajCFSH-knockdown female and male juveniles changed their body color to become brighter, indicating that MajCFSH has the ability to change body color by dispersing the pigment granules in the chromatophore. Overall, our present study improved our understanding of the physiological roles of CFSH using kuruma prawn.Highlights-MajCFSH-knockdown was conducted using sexually immature juveniles of kuruma prawn.-MajCFSH-knockdown male juveniles showed significant growth suppression.-MajCFSH-knockdown female and male juveniles changed their body color to become brighter.