Cloning And Expression Of Androgen Receptor In Scatophagus Argus

Sarcophagus Argus is one of the euryhaline marine fish species in China, distributed mainly in exten ded shore and estuarine waters regions, and cultivated in fresh water after domesticating.Sarcophagu s Argus is very popular owing to the value of beautiful body, tender meat and abundant nutrition. The whole problem of the seed breeding has not been effectively resolved. Therefore, it is necessary to increase theoretical research about the reproductive regulation of Sarcophagus Argus.we carried out the following several studies on Sarcophagus Argus:1 AR cloning and identification in Sarcophagus Argus. By SMART-RACE technology, the AR cDNA of Sarcophagus Argus was isolated from testis. the full-length cDNA of AR is2425 bp,consisting of a 5’-terminal untranslated region(UTR) of 11 bp, a 3’-terminal UTR of 126 bp and an open reading frame(ORF) of 2289 bp, encoded a 20.07 kDa protein of 763 amino acids(aa).By multiple amino acids sequence alignment, AR had the typical characteristics of nuclear receptor superfamily. Phylogenetic analysis indicated the closer relationship and high score similarity with AR of Dicentrarchus labrax。2. AR time-spatial expression in Sarcophagus Argus.RT-PCR revealed that AR highly expressed in these male fish tissues examined: pituitary, testis; in female fish pituitary, ovary, heart. AR showed significant tissue-specific patterns in male and female.AR Expression was determined in the early,middle, and mature stages of testis of Sarcophagus Argus by quantitative real time-PCR. Expression level in the middle development stage was significantly higher than the early and mature stage. This assay indicates that AR plays more important regulatory role in the middle developmental stage of testis.3. AR expression in steroids treatment. AR and the related-steroid factor expression were determined in 1M E2 and T treatment in vitro. Results showed that E2 could significantly inhibit AR expression, and stimulate P450 a and Foxl2 expression at the same time. And it is opposite in MT treatment. These implied that the ovary would become plastic under exogenous androgen.This study performed the time- spatial expression of androgen receptor of Sarcophagus Argus and incubation in vitro of exogenous steroid hormone. The result showed that androgens can stimulate the expression of AR, and inhibit the female related genes. It suggests the sensitivity of Sarcophagus Argus ovary with the androgens treatment, which provides the theoretical basis on sex reversal, and provides theoretical guidance for artificial pseudo-male for all female seed breeding.