Fisheries College, Jimei University, Xiamen, 361021, China; Engineering Research Center of the Modern Technology for Eel Industry, Ministry of Education, Xiamen, 361021, China; Key Laboratory of Cultivation and High-value Utilization of Marine Organisms in Fujian Province, Xiamen, 361013, China.
Fisheries College, Jimei University, Xiamen, 361021, China; Engineering Research Center of the Modern Technology for Eel Industry, Ministry of Education, Xiamen, 361021, China.
Theriogenology. 2022 Mar 1;180:176-188. doi: 10.1016/j.theriogenology.2021.12.031. Epub 2021 Dec 29.
Inducing maturation of the ovaries to enable the production of good-quality eggs is critical for the successful artificial breeding of Anguilla japonica. During the spawning season, however, the ovaries of A. japonica have been found to develop into asynchronous clutches, impeding the success of artificial breeding on a commercial scale. The dynamic molecular regulation of follicular development in the same individual was assessed by transcriptome analysis of the five stages of follicles, the pre-vitellogenic, early vitellogenic, midvitellogenic, late vitellogenic, and migratory nucleus stages in artificial maturing A. japonica. Comparisons across these developmental stages identified a total of 19,298 differentially expressed transcripts (DETs). Short time-series expression miner analysis across these DETs revealed four significant expression profiles. Gene Ontology function and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses found that some of the significantly enriched biological processes and metabolic pathways included those related to steroid hormone biosynthesis (cyp11a1, cyp17a1, cyp17a2, hsd17b1, and hsd17b12), cargo receptor activity (vtgr and vldlr), meiosis and ovulation (pgrs and mPRγ), hydration (cts and aqp1), and egg coat formation (zp). These genes and pathways were associated with serum 17β-estradiol concentrations and morphological changes. The levels of hsd17b12 and mPRγ mRNAs were much higher during the migratory nucleus stage, suggesting their respective involvement in the biosynthesis and functional pathway of the maturation-inducing steroid 17α,20β-dihydroxy-4-pregnen-3-one. The gene subtypes aqp1b and ctsd may regulate water influx into oocytes and yolk protein proteolysis, respectively. To our knowledge, the present study is the first to describe combined transcriptome profiling of asynchronously developing follicles in the same individual. The findings suggest that steroid hormone synthesis and nutrient absorption in follicular somatic cells play important roles during follicular development and maturation, despite the same external physiological surroundings.
诱导卵巢成熟以产生高质量卵子对于成功进行人工养殖日本鳗鲡至关重要。然而，在繁殖季节，发现日本鳗鲡的卵巢发育为异步卵群，这阻碍了商业规模的人工养殖的成功。通过对人工成熟的日本鳗鲡的五个卵泡阶段（卵黄前发生期、早期卵黄发生期、中期卵黄发生期、晚期卵黄发生期和迁移核期）的转录组分析，评估了同一个体中卵泡发育的动态分子调控。在这些发育阶段之间的比较中共鉴定出 19298 个差异表达转录本（DETs）。对这些 DETs 的短时间序列表达矿化分析揭示了四个显著的表达谱。基因本体论功能和京都基因与基因组百科全书途径富集分析发现，一些显著富集的生物学过程和代谢途径包括与类固醇激素生物合成（cyp11a1、cyp17a1、cyp17a2、hsd17b1 和 hsd17b12）、货物受体活性（vtgr 和 vldlr）、减数分裂和排卵（pgrs 和 mPRγ）、水合作用（cts 和 aqp1）和卵壳形成（zp）相关的过程和途径。这些基因和途径与血清 17β-雌二醇浓度和形态变化有关。在迁移核期，hsd17b12 和 mPRγ mRNAs 的水平要高得多，这表明它们分别参与成熟诱导类固醇 17α,20β-二羟基-4-孕烯-3-酮的生物合成和功能途径。基因亚型 aqp1b 和 ctsd 可能分别调节卵母细胞和卵黄蛋白水解的水流入。据我们所知，本研究首次描述了同一个体中异步发育卵泡的联合转录组分析。研究结果表明，尽管外部生理环境相同，但类固醇激素合成和卵泡体细胞中的营养吸收在卵泡发育和成熟过程中发挥着重要作用。
