Rojo-Bartolomé Iratxe, Valencia Ainara, Cancio Ibon
CBET Research Group, Dept. of Zoology and Animal Cell Biology, Research Centre for Experimental Marine Biology and Biotechnology of Plentzia (PiE-UPV/EHU), University of the Basque Country (UPV/EHU), Areatza, z/g, E-48620 Plentzia, Basque Country, Spain.
CBET Research Group, Dept. of Zoology and Animal Cell Biology, Research Centre for Experimental Marine Biology and Biotechnology of Plentzia (PiE-UPV/EHU), University of the Basque Country (UPV/EHU), Areatza, z/g, E-48620 Plentzia, Basque Country, Spain.
Mar Pollut Bull. 2017 Aug 15;121(1-2):292-301. doi: 10.1016/j.marpolbul.2017.06.027. Epub 2017 Jun 13.
One of the best described effects of environmental xenoestrogens in fish is the generation of intersex gonads in males. Considering 5S rRNA a marker of the presence of oocytes, a 5S/18S rRNA index was calculated in 296 thicklip grey mullets (Chelon labrosus) from polluted environments. In addition, qPCR analysis of transcription factors gtf3a and ubtf1, related respectively to 5S and 18S rRNA synthesis, was conducted along female-oogenesis. 5S/18S rRNA index identified sex with a threshold value of 0.4521 separating males from females. Histological analysis identified 38 intersex individuals. Intersex severity and 5S/18S rRNA indexes were correlated. 5S/18S rRNA index identified ovarian developmental stage with high 5S rRNA levels during early oogenesis and 18S rRNA relative values increasing towards maturation. gtf3a and ubtf1 transcription levels followed the pattern of 5S rRNA accumulation. Thus, ribogenesis genes provide easy/quantitative methods to molecularly identify the sex, female gametogenic stage and intersex severity in mullets.
环境异源雌激素对鱼类最显著的影响之一是导致雄鱼出现雌雄同体性腺。将5S rRNA作为卵母细胞存在的标志物，对来自污染环境的296条厚唇灰鲻（Chelon labrosus）计算5S/18S rRNA指数。此外，在雌性卵子发生过程中，对分别与5S和18S rRNA合成相关的转录因子gtf3a和ubtf1进行了qPCR分析。5S/18S rRNA指数以0.4521的阈值区分雌雄。组织学分析鉴定出38个雌雄同体个体。雌雄同体严重程度与5S/18S rRNA指数相关。5S/18S rRNA指数可识别卵巢发育阶段，在卵子发生早期5S rRNA水平较高，而18S rRNA相对值随着成熟而增加。gtf3a和ubtf1转录水平遵循5S rRNA积累模式。因此，核糖体生成基因提供了简便/定量的方法，用于从分子水平鉴定鲻鱼的性别、雌性配子发生阶段和雌雄同体严重程度。
