MnFtz-f1 Is Required for Molting and Ovulation of the Oriental River Prawn Macrobrachium nipponense

Abstract

Molting and ovulation are the basic processes responsible for the growth and reproduction of Macrobrachium nipponense; however, the molecular mechanisms of molting and ovulation in M. nipponense are poorly understood. The present study aimed to use MnFtz-f1 as the starting point to study the molting and ovulation phenomena in M. nipponense at the molecular level. The full-length MnFtz-f1 cDNA sequence was 2,198 base pairs (bp) in length with an open reading frame of 1,899 bp encoding 632 amino acids. Quantitative real-time PCR analysis showed that MnFtz-f1 was highly expressed in the ovary at the cleavage stage and on the fifth day after hatching. In vivo administration of 20-hydroxyecdysone (20E) showed that 20E effectively inhibited the expression of the MnFtz-f1 gene, and the silencing of the MnFtz-f1 gene reduced the content of 20E in the ovary. In situ hybridization (ISH) analysis revealed the localization of MnFtz-f1 in the ovary. Silencing of MnFtz-f1 by RNA interference (RNAi) resulted in significant inhibition of the expression of the vitellogenin (Vg), Spook, and Phantom genes, thus confirming that MnFtz-f1 had a mutual regulatory relationship with Vg, Spook, and Phantom. After RNAi, the molting frequency and ovulation number of M. nipponense decreased significantly, which demonstrated that MnFtz-f1 played a pivotal role in the process of molting and ovulation.

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

“…The RT‐qPCR results showed that CqFtz‐f1 abundances gradually increased from Stage I to IV, and reached peak level at mature ovary. This finding was consistent with results from studies performed in other crustaceans (Li, Li, Wen, et al, 2012; Yuan et al, 2021).…”

“…It was noted that staging based on ovarian morphology and histology was considered to be more appropriate (Wang et al, 2020). This finding was consistent with results from studies performed in other crustaceans (Li, Li, Wen, et al, 2012;Yuan et al, 2021).…”

“…Tissues distribution in several species showed that CqFtz-f1 extensively transcripted among different tissues, but uniformly reached at the highest level in the ovary (Chan & Chan, 1999;Yuan et al, 2021). Interestingly, the expression profile of CqFtz-f1 in go- The phylogenetic tree with neighbour-joining method (1000 replicates).…”

“…Tissues distribution in several species showed that CqFtz‐f1 extensively transcripted among different tissues, but uniformly reached at the highest level in the ovary (Chan & Chan, 1999; Yuan et al, 2021). Interestingly, the expression profile of CqFtz‐f1 in gonads from C. quadricarinatus exhibited a sexual dimorphic expression pattern, indicating that it belonged to SF‐1/Ad4BP subgroup.…”

“…In Portunus trituberculatus , the function of Ftz‐f1 was also investigated in different moulting stages, and inferred that Ftz‐f1 played a regulatory role in moulting process (Zhang et al, 2015). Recently, RNAi‐mediated gene silencing assay showed that the moulting frequency and ovulation number of Macrobrachium nipponense decreased significantly after Ftz‐f1 expression interference, which indicated that Ftz‐f1 played a pivotal role in the process of moulting and ovulation (Yuan et al, 2021). Taken together, Ftz‐f1 owned great potential role in regulating gonad development and moulting processes in decapod crustaceans.…”