Zhao Yan, Zhou Haotian, Ayisi Christian Larbi, Wang Yan, Wang Jun, Chen Xiaowu, Zhao Jinling
Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, Shanghai Ocean University, 201306, Shanghai, China
National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, 201306, Shanghai, China.
Biol Open. 2018 Apr 18;7(4):bio029082. doi: 10.1242/bio.029082.
MicroRNAs may affect stress responses because they act as rapid responders at the post-translation level. In this study, we found that miR-26a is abundantly expressed in the brain and gill tissues of tilapia. Expression of miR-26a in the brain decreased significantly with increasing ammonia concentrations using stem-loop qPCR. To analyze the function of miRNA , miR-26a was stably knocked down with an antagomir in tilapia. Following ammonia challenge, miR-26a antagomir treatment significantly suppressed blood ammonia/[Cl]/[K] concentration and the reactive oxygen species production, while it markedly enhanced glutamine accumulation and antioxidant enzyme activity in the brain of tilapia, indicating that miR-26a may be involved in the remission of physiological disturbances resulting from ammonia stress. We strongly conclude that there is a direct link between miR-26a and the responses to ammonia in tilapia. Furthermore, bioinformatics analysis and luciferase assays demonstrated that miR-26a regulates (heat shock protein 70) and (glutamine synthetase) expression by targeting their 3'-UTR and that the suppression of miR-26a could increase the intracellular level of and .
微小RNA可能会影响应激反应，因为它们在翻译后水平上充当快速反应者。在本研究中，我们发现miR-26a在罗非鱼的脑和鳃组织中大量表达。使用茎环定量聚合酶链反应，随着氨浓度的增加，脑中miR-26a的表达显著降低。为了分析微小RNA的功能，在罗非鱼中用抗微小RNA稳定敲低miR-26a。氨应激后，miR-26a抗微小RNA处理显著抑制了血氨/[Cl]/[K]浓度和活性氧的产生，同时显著增强了罗非鱼脑中谷氨酰胺的积累和抗氧化酶活性，表明miR-26a可能参与了氨应激导致的生理紊乱的缓解。我们有力地得出结论，miR-26a与罗非鱼对氨的反应之间存在直接联系。此外，生物信息学分析和荧光素酶测定表明，miR-26a通过靶向热休克蛋白70和谷氨酰胺合成酶的3'-非翻译区来调节它们的表达，并且抑制miR-26a可以增加细胞内热休克蛋白70和谷氨酰胺合成酶的水平。
