摘要
在脊椎动物中,许多基因参与了性腺的分化和性别的决定过程,Doublesex and mab-3-related transcription factor1（Dmrt1）编码了一个具有DM框的转录因子,在哺乳类、鸟类、两栖类、爬行类和鱼类中与雄性性腺的分化和形成有关,是一种目前已知从无脊椎动物到人最保守的性别分化相关基因。半滑舌鳎（Cynoglossus semilaevis）是近年来新开发的一种理想的增养殖对象,雌性个体生长速度比雄性快2-3倍,为了探索半滑舌鳎的性别决定机理,培育全雌苗种,实现单性养殖,本研究采用同源克隆策略,从半滑舌鳎精巢中获得Dmrt1α cDNA全长1149bp,其中包含777bp的开放阅读框（ORF）,45bp长的5’末端非编码区（UTR）,327bp长的3’末端UTR。氨基酸序列分析表明半滑舌鳎与其他鱼类Dmrt1基因的氨基酸序列同源性为41.9%-58.1%,与鼠和人的Dmrt1氨基酸序列同源性较低,只有32.6%和33.7%。RT-PCR分析表明,Dmrt1α只在半滑舌鳎的精巢中表达,而在雌、雄鱼的脑、肝脏、脾脏、肾脏、肌肉、皮肤、心肌、肠、头肾、鳃、皮肤、小肠、眼以及雌鱼的卵巢中都不表达。与对照组雄鱼和经过甲基睾酮（Methyltestosterone,MT）浸浴处理和高温处理的雄鱼一样,Dmrt1α也在甲基睾酮（MT）处理和高温诱导的由雌性性反转为雄性的精巢中表达,而未经诱导或诱导不成功的雌鱼中仍没有Dmrt1α表达,这些结果表明Dmrt1α可能参与了半滑舌鳎的雄性性别决定过程。
Many genes are known to be involved in gonadal differentiation in vertebrates. Doublesex and mab-3- related transcription factor 1 （Dmrt1）, a gene that encodes a transcription factor with a DM-domain, is considered to be one of the essential genes controlling testicular differentiation in mammals, birds, reptiles, amphibians and fish. Dmrt1 has been suggested to be the first conserved gene involved in sex differentiation found from invertebrates to human. Half-smooth tongue-sole （Cynoglossus semilaevis） is a newly exploited and commercially important cultured marine flatfish. Females grow 2-3 times faster than males. To clarify the mechanism of sex reversal and gain all-female tongue sole stock would be significantly beneficial for aquaculture. The full-length cDNA of the half-smooth tongue-sole Dmrt 1 α was isolated from testis of tongue sole by using homologous cloning method, which was 1 149 bp in length, including 45 bp of 5＇ terminal UTR, 777 bp encoding region and 327 bp of 3＇ terminal UTR. The putative Dmrt1α amino acid of tongue sole shared 41.9%-58.1% sequence identity with other fish Dmrt1. However there was only 32.6% and 33.7% sequence identify with that of mouse and human. The RT-PCR analysis reveals that Dmrt1α mRNA was only expressed in the testis, but not in ovary, brain, liver, spleen, kidney, muscle, skin, heart, head kidney, gill, intestine, and eyes. However, it also expressed in the testis of sex-reversed male treatment by Methyltestosterone or high temperature. These results suggested that Dmrt1α may be involved in the male sex determination of tongue sole.
出处
《中国水产科学》
CAS
CSCD
北大核心
2008年第4期577-584,共8页
Journal of Fishery Sciences of China
基金
国家863计划项目(2006AA10A403)
山东省泰山学者工程专项经费
山东省农业良种工程重大项目
