Vazirzadeh Arya, Guiguen Yann
Department of Natural Resources and Environmental Engineering, School of Agriculture, Shiraz University, Shiraz, Iran.
Institut National de la Recherche Agronomique, SCRIBE, Campus de Beaulieu, 35042, Rennes Cedex, France.
Anim Reprod Sci. 2017 Sep;184:139-148. doi: 10.1016/j.anireprosci.2017.07.009. Epub 2017 Jul 14.
The patterns of expression of two subunits of 20β-hydroxysteroid dehydrogenase (20β-HSD), key enzyme involved in the biosynthesis and activation of steroid hormones, were examined in rainbow trout by using a combination of quantitative real-time PCR and in-situ hybridization. The expression of targeted genes was examined in mRNA extracted from different tissues at different gonadal stages in male and female trout. Both subunits of 20β-HSD were found to be widely distributed in tissues. The highest expression of 20β-HSD A was found in intestine followed by skin, stomach, liver and gills, whereas, the highest expression of 20β-HSD B was observed in stomach followed by head kidney, ovary - at late vitellogenesis stage- and trunk kidney. In ovarian tissue 20β-HSD A was highly expressed in mature oocytes, and the highest expression of 20β-HSD B was in ovary at late vitellogenesis stage. There were no differences in the level of expression of either subunit among groups of rainbow trout at different stages of maturational competence. In male fish, 20β-HSD A was highly expressed in testis stage I in contrast to 20β-HSD B which was highly expressed in testis stage VIII. In situ- hybridization results showed that the 20β-HSD gene was highly expressed in gastrointestinal organs, while only slightly expressed in the gonadal tissue of fish at stage 62day-post-fertilization (dpf). Overall, the results confirm the ubiquitous presence of 20β-HSD among tissues in rainbow trout with relatively minor fluctuations in expression associated with reproductive cycles which collectively suggests a wider metabolic role of these enzymes than just an association with the synthesis of control hormones for reproduction.
采用定量实时聚合酶链反应（PCR）和原位杂交相结合的方法，检测了虹鳟鱼体内20β-羟基类固醇脱氢酶（20β-HSD）两个亚基的表达模式。20β-HSD是类固醇激素生物合成和激活过程中的关键酶。在雌雄虹鳟鱼不同性腺发育阶段的不同组织中提取mRNA，检测目的基因的表达。结果发现，20β-HSD的两个亚基在组织中广泛分布。20β-HSD A亚基在肠道中的表达最高，其次是皮肤、胃、肝脏和鳃；而20β-HSD B亚基在胃中的表达最高，其次是头肾、处于卵黄发生后期的卵巢和躯干肾。在卵巢组织中，20β-HSD A在成熟卵母细胞中高表达，而20β-HSD B亚基在卵黄发生后期的卵巢中表达最高。在不同成熟能力阶段的虹鳟鱼群体中，两个亚基的表达水平没有差异。在雄鱼中，20β-HSD A在Ⅰ期精巢中高表达，而20β-HSD B在Ⅷ期精巢中高表达。原位杂交结果显示，20β-HSD基因在胃肠道器官中高表达，而在受精后62天（dpf）的鱼性腺组织中表达较弱。总体而言，结果证实了20β-HSD在虹鳟鱼组织中普遍存在，其表达随生殖周期的波动相对较小，这表明这些酶的代谢作用比仅与生殖控制激素合成相关更为广泛。
