Modulation of complex coordinated molecular signaling by 5HT and a cocktail of inhibitors leads to ovarian maturation of Penaeus monodon in captivity

Abstract

In aquaculture practices, prawn cultivation holds the major share and Penaeus monodon is the main species cultured. The decline in production of P. monodon is mainly due to the limited availability of domesticated broodstock, which is attributed to its reproductive cycle, controlled by complex coordinated signaling mechanisms. Unilateral eyestalk ablation of domesticated females held in captivity is done to induce ovary development, which has certain disadvantages, including a high rate of mortality. Thus, developing alternative techniques for eyestalk ablation in captive broodstock is necessary to induce maturation of ovary. This study exemplifies the role of 5HT along with a cocktail of inhibitors (U0126, Rp-cAMP, and LY294002) in inducing ovarian maturation. In this study, inhibition of pERK by U0126 inhibited vitellogenesis-inhibiting hormone (VIH), which in turn led to the overexpression of vitellogenin. 5HT induces steroidogenesis (estradiol-17β) through induction of the gonadotropin-releasing hormone by activating calcium-calmodulin signaling. Steroidogenesis is also aided by synthesis of StAR protein. Estradiol-17β stimulates the formation of the maturation-promoting factor (MPF) complex by cdc25 activation and Myt1 inactivation. LY294002 aids in keeping cdc25 activated by inhibiting calcium-calmodulin induced phosphorylation of Akt which is a negative regulator of mitogen-activated protein kinases. VIH induced activation of Myt1, through protein kinase A (PKA), was inhibited by Rp-cAMP which inhibits adenylate cyclase, thus stabilizing the activated MPF complex. To conclude, the coordinated effect of inhibitors and 5HT accelerates the development of ovary from previtellogenic to matured oocytes, yielding high quality and quantity larvae compared with eyestalkablated P. monodon. K E Y W O R D S 5HT, calcium-calmodulin signaling, captivity, cdc25, ERK, MPF, Myt-1, ovarian maturation, Penaeus monodon, steroidogenesis, vitellogenesis

Putative role of corazonin in the ovarian development of the swimming crab Portunus trituberculatus

“…This induction was further confirmed by treating with CrzR dsRNA, which might suggest an integrative role of Crz signaling during ovarian development. Moreover, this result conforms to the properties of CrzR as a GPCR, as in many studies, the intracellular cAMP level plays pivotal roles in regulating the expression of Vg, cyclinB, and Cdc2 Mani et al, 2019;Feng et al, 2021;Wan et al, 2022).…”

Molecular characterization of the Ftz‐f1 gene in redclaw crayfish Cherax quadricarinatus and its potential role in ovarian development

“…Previous studies showed that eyestalk ablation had the ability to promote gonad maturation and reproduction in female crustaceans, which disturbed the process of synthesis and release of gonad inhibiting hormone (Mani et al, 2019). Here, expression of CqFtz‐f1 mRNA after eyestalk ablation was measured, and we found that CqFtz‐f1 expression was increased significantly at 24 and 96 h compared with the control group.…”