Cloning of the Ecdysone Receptor Gene from the Chinese Mitten Crab, Eriocheir sinensis, and Sexually Dimorphic Expression of Two Splice Variants

Abstract

The ecdysone receptor (EcR), a member of the nuclear receptor superfamily, plays an important role in molting in crustaceans and insects. Here, we report the cloning of the full‐length cDNA of the EcR gene from Eriocheir sinensis (EsEcR). A 477 bp alternatively spliced intron was identified, with two splice variants. One, EsEcR‐L, is 2522 bp long and encodes a 577 amino acid protein. The second, EsEcR‐S, is 2045 bp long and encodes a 422 amino acid protein. Among eight different tissues, the expression of EsEcR was highest in the hepatopancreas and lowest in the heart. EsEcR was expressed during different embryonal developmental stages, and its expression reached the highest level at the original zoea stage. EsEcR‐L was specifically expressed in testis among eight examined tissues and was also the predominantly expressed form in testis, while in other tissues the predominantly expressed form was EsEcR‐S, indicating different roles of these splice variants in males and females. EsEcR‐L was also expressed in embryos. The responses of EsEcR and EsEcR‐L after eyestalk ablation (ESA) were investigated in four tissues, including hepatopancreas, muscle, testis, and ovary. The expression of EsEcR was upregulated after ESA in hepatopancreas, muscle, and ovary, while the expression of EsEcR‐L was downregulated after ESA.

Cloning and Expression of Ecdysone Receptor and Retinoid X Receptor from Procambarus clarkii: Induction by Eyestalk Ablation

“…The expressions were also affected by the other factors. Also, a similar result was observed in Eriocheir sinensis [24]. The variable effect in different tissues after ESA indicates different tissues may have a notable difference in sensitivity to the concentration and a specific type of Ecds and may coordinate their inherent specific functions during molting and gonad maturation.…”

“…To date, EcRs and RXRs have been reported from many crustaceans, including the EcR and RXR from the fiddler crab Uca pugilator [11], the EcR from the land crab Gecarcinus lateralis [12], the EcR and RXR from the kuruma prawn Marsupenaeus japonicus [13], the EcR and RXR from the water flea Daphina magna [14], the EcR from the intertidal copepod Tigriopus japonicas [15], the EcR and RXR from the brown shrimp Crangon crangon [16], the EcR from the mysid shrimp Americamysis bahia [17], the EcR and RXR from the American lobster Homarus americanus [18], the EcR from the harpacticoid copepod Amphiascus tenuiremis [19], the EcR from the blue crab Callinectes sapidus [20], the EcR and RXR from the opossum shrimp Neomysis integer [21] and the EcR and RXR from the freshwater prawn Macrobrachium nipponense [22,23] and the EcR from the Chinese mitten crab Eriocheir sinensis [24]. …”

The nuclear receptor E75 from the swimming crab, Portunus trituberculatus: cDNA cloning, transcriptional analysis, and putative roles on expression of ecdysteroid-related genes

“…3), but also in other crustacean species previously reported (Chan, 1998;Kim et al, 2005;Qian et al, 2014). Taken together with the wide distribution of the receptor heterodimer of EcR (Cui et al, 2013;Gong et al, 2015;Qian et al, 2014;Shen et al, 2015) and RXR (Kim et al, 2005;Tang et al, 2014;Techa and Chung, 2013;Tiu et al, 2012), we suggest that the 20E/EcR/RXR complex can act through E75 upon a diversity of target tissues thereby mediating the molting process. Relatively high expression of PtE75 was found in the epidermis, eyestalk, and muscle, this is consistent with the distribution features of E75 in L. vannamei (Qian et al, 2014).…”

Structure and function of the alternatively spliced isoforms of the ecdysone receptor gene in the Chinese mitten crab, Eriocheir sinensis

“…The Chinese mitten crab, Eriocheir sinensis , is an economically important farmed species in East Asia and is an extensively influential species in Europe and Northern America 36 , 37 . E. sinensis presents the representative biological characteristics of crustaceans, such as molting, metamorphosis, regeneration, development, and reproduction 38 – 41 . Elucidating EcR structure and its alternative isoforms will help us decipher the functional roles of EcR in E. sinensis and expand our knowledge of the crustaceans EcR .…”

“…Elucidating EcR structure and its alternative isoforms will help us decipher the functional roles of EcR in E. sinensis and expand our knowledge of the crustaceans EcR . However, studies that are related to the structure and function of the alternative isoforms in E. sinensis are sparse 41 . In the current study, we obtained the whole EcR gene sequence, clearly deciphered the EcR gene structure, and identified four EcR alternative isoforms from E. sinensis .…”