奥利亚罗非鱼DMO和DMT基因的时空表达特征分析  

Temporal and spatial expression of DMO and DMT gene in Oreochromis aurea

作　　者：曹谨玲[1] 俞菊华[2] 曹哲民[2] 李建琳[2] 吴婷婷[2] 

机构地区：[1]南京农业大学无锡渔业学院,江苏无锡214081 [2]中国水产科学研究院淡水渔业研究中心农业部水生动物遗传育种和养殖生物学重点开放实验室,江苏无锡214081

出　　处：《水产学报》2007年第2期129-136,共8页Journal of Fisheries of China

基　　金：国家"八六三"高新技术发展计划(2004AA243060);国家"九七三"计划(2004CB117401);国家"十五"重点科技攻关计划(2004BA526B0110)

摘　　要：采用荧光定量RT-PCR方法对奥利亚罗非鱼DMO和DMT基因的时空表达进行了研究。结果发现,这两个基因均从原肠胚早期开始转录,一直到出膜,都维持着较高的表达水平,但DMO表达量明显高于DMT。从鱼苗孵化出膜的第1天开始,随着日龄的增加,DMO和DMT基因的表达量均增加,但DMO在性腺和脑中都能表达,而DMT则仅在精巢中专一性表达。鱼苗性腺分化时期,也可影响DMO和DMT基因的表达量,提示它们可能与激素调控有关。在雌、雄鱼的肝和肾等5种组织中均检测不到这两个基因转录本的存在;在脑中仅可检测到DMO基因不同强弱的转录本,呈现出很强的中枢神经系统的表达特异性。此外,在成体的卵巢和精巢中分别只可检测到DMO和DMT基因的大量表达,显示二者在性别决定和分化中的重要功能。奥利亚罗非鱼DMO基因在其中枢神经系统发育及卵巢发生和功能维持上有着重要功能;DMT基因在精巢发生和功能维持上起重要作用。The DMRT genes constitute a new gene family related to sex determination. Like the double-sex gene of Drosophila melanogaster and the mab-3 gene of Caenorhabditis elegents, they encode transcription factors characterized by a conserved zinc-finger like DNA-binding motif, the DM domain, which is thought to bind DNA in the process of sex differentiation and development. In 1998, DMRT1 genes were first identified and found containing DM domain in Homo sapiens and Mus musculus. And DMRT1 was found to regulate sex determination and differentiation in vertebrates extensively. So far, the DMRT genes have been discovered in a wide range of animal species, such as fish, amphibian, reptiles, birds, and mammals. These evidently reveal the evolutionary conservation of DMRT gene family. Tilapia is the most important breeding fish throughout the world. As to Oreochromis aurea, sex is an important economic character, for the male is bigger than the female. So to clarify the mechanism of Oreochromis aurea sex determination will be of great importance in both theory and application. With the hope of doing further research on the function of DMRT genes and clarifying the molecular mechanism of Oreochromis aurea, Real-time Quantitative RT-PCR was used in this research to analyze the temporal and spatial expression patterns on the basis of DMO and DMT gene sequences obtained. Their transcripts appeared from early gastrulae stage during embryonic development, and maintained a considerable high level till the one day＇s fry, but level of DMO was higher than that of DMT. With the increase of age, the levels of DMO discovered in ovary and brain and DMT only observed in testis both improve. During sex differentiation, after treatment with hormone for 30 days, level of DMO in estrogen group is significantly higher than that in control group （ P 〈 0.05 ）, while level of DMO in Hydroxyandrostenedione group, aromatase Ⅰ and aromatase Ⅱ are remarkably lower than those in control group （ P 〈 0.05 ） ; levels of DMO in all

关 键 词：奥利亚罗非鱼 DMO DMT 时空表达 荧光定量 

分 类 号：Q786[生物学—分子生物学] S917.4[农业科学—水产科学]