본 연구에서는 넙치(Paralichthys olivaceus) 정소로부터 DMRT-1 partial cDNA를 분리하였다. 넙치 DMRT-1은 317개의 염기로 구성되어 있으며, Atlantic halibut, 감성돔 및 무지개 송어와 각각 94%, 85%, 82%의 높은 상동성을 보였다. RT-PCR을 이용하여 DMRT-1 mRNA 발현은 난소보다 정소에서 높게 나타난 것을 관찰할 수 있었다. 또한, 암컷 넙치에 웅성호르몬인 testosterone 처리시 처리 농도에 따라 난소에서 DMRT-1 mRNA 발현이 증가함을 볼 수 있었다. 따라서, DMRT-1은 수컷에서 특이적으로 발현되는 유전자임을 알 수 있으며, 본 연구의 결과는 넙치의 성 전환 및 유도에 대한 기초자료를 제공할 것이다.
We isolated a 317 bp of partial cDNA for doublesex-and mab-3-related transcription factor-1 (DMRT-1) from the testis of olive flounder, Paralichthys olivaceus using RT-PCR. Based on the multiple sequence alignment, olive flounder DMRT-1 shared relatively high sequence homology (82 to 94%) with orthologues from other teleost species such as Atlantic halibut, Hippoglossus hippoglossus, black porgy, Acanthopagrus schlegeli and rainbow trout, Oncorhynchus mykiss. DMRT-1 mRNA was predominantly expressed in the testis of olive flounder. In our investigation for the effect of testosterone treatment in vivo on induced expression of ovarian DMRT-1 transcript, mRNA levels of DMRT-1 in ovary were significantly up-regulated by testosterone treatments (0.3 or $3.0{mu}g$ testosterone/g body weight for 12 to 36 hours) as judged by RT-PCR analysis. In overall, transcriptional stimulation of DMRT-1 during treatments was more affected by doses of testosterone than treatment durations. This result strongly suggests that the regulation of DMRT-1 be tissue- and gender-specific in olive flounder, and also provides useful baseline knowledge on the testosterone-mediated regulation in the reproductive physiology of this species.
