Endogenous biosynthesis of docosahexaenoic acid(DHA)regulates fish oocyte maturation by promoting pregnenolone production  

作　　者：Yi Li Xuehui Li Ding Ye Ru Zhang Chengjie Liu Mudan He Houpeng Wang Wei Hu Yonghua Sun 

机构地区：[1]State Key Laboratory of Freshwater Ecology and Biotechnology,Institute of Hydrobiology,Innovation Academy for Seed Design,Chinese Academy of Sciences,Wuhan,Hubei 430072,China [2]College of Advanced Agricultural Sciences,University of Chinese Academy of Sciences,Beijing 100049,China [3]Hubei Hongshan Laboratory,Wuhan,Hubei 430070,China

出　　处：《Zoological Research》2024年第1期176-188,共13页动物学研究（英文）

基　　金：supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Precision Seed Design and Breeding,XDA24010108);National Natural Science Foundation of China(31972780&31721005);National Key R&D Program of China(2018YFA0801000);State Key Laboratory of Freshwater Ecology and Biotechnology(2019FBZ05)。

摘　　要：Omega-3 polyunsaturated fatty acids(n-3 PUFAs),particularly docosahexaenoic acid(22:6n-3,DHA),play crucial roles in the reproductive health of vertebrates,including humans.Nevertheless,the underlying mechanism related to this phenomenon remains largely unknown.In this study,we employed two zebrafish genetic models,i.e.,elovl2^(-/-)mutant as an endogenous DHAdeficient model and fat1(omega-3 desaturase encoding gene)transgenic zebrafish as an endogenous DHA-rich model,to investigate the effects of DHA on oocyte maturation and quality.Results show that the elovl2^(-/-)mutants had much lower fecundity and poorer oocyte quality than the wild-type controls,while the fat1 zebrafish had higher fecundity and better oocyte quality than wildtype controls.DHA deficiency in elovl2^(-/-)embryos led to defects in egg activation,poor microtubule stability,and reduced pregnenolone levels.Further study revealed that DHA promoted pregnenolone synthesis by enhancing transcription of cyp11a1,which encodes the cholesterol side-chain cleavage enzyme,thereby stabilizing microtubule assembly during oogenesis.In turn,the hypothalamic-pituitary-gonadal axis was enhanced by DHA.In conclusion,using two unique genetic models,our findings demonstrate that endogenously synthesized DHA promotes oocyte maturation and quality by promoting pregnenolone production via transcriptional regulation of cyp11a1.

关 键 词：Docosahexaenoic acid Oocyte maturation Oocyte quality PREGNENOLONE MICROTUBULE 

分 类 号：S917.4[农业科学—水产科学]