Could Crustaceans' Ovary Synthesize Ecdysone? First Evidence in a Crab Species During Intermolt.

The function of ecdysone in promoting molting is widely known in arthropods. Moreover, in insects, ecdysone synthesis in the ovary is involved in reproduction and development. In crustaceans, some studies conducted in species with the molt linked to mating have shown that ecdysone produced by the Y organ stimulates ovarian maturation, but scarce evidence about the capacity of the ovary itself to synthesize ecdysone is currently available. The present study provides the first evidence of the expression of a putative shadow gene (sad, cytochrome P450 CYP315A1), involved in the ecdysone synthesis pathway, in the ovary of the estuarine crab Neohelice granulata, considered a derived species with the molt not linked to mating. The obtained results provide the first evidence for future studies testing the hypothesis that during the intermolt period, the mature ovary of females synthesizes ecdysone to locally act on the female vulvae to promote its decalcification, allowing mating. These results are discussed considering phylogenetic relationships among Arthropoda.