Israel Oceanographic and Limnological Research, The National Center for Mariculture (NCM), P.O.B. 1212, 88112, Eilat, Israel.
Hopkins Marine Station of Stanford University, 120 Ocean View Blvd, Pacific Grove, CA, 93950, USA.
Sci Rep. 2024 Oct 5;14(1):23191. doi: 10.1038/s41598-024-74152-7.
This study elucidated the role of DHA-modulated genes in the development and growth of Atlantic bluefin tuna (Thunnus thynnus) larvae ingesting increasing levels of DHA in their rotifer prey. The effect of feeding low, medium, and high rotifer (Brachionus rotundiformis) DHA levels (2.0, 3.6 and 10.9 mg DHA g DW, respectively) was tested on 2-15 days post hatching (dph) bluefin tuna larvae. Larval DHA content markedly (P < 0.05) increased in a DHA dose-dependent manner (1.5, 3.9, 6.1 mg DHA g DW larva, respectively), that was positively correlated with larval prey consumption and growth (P < 0.05). Gene ontology enrichment analyses of differentially expressed genes (DEGs) demonstrated dietary DHA significantly (P < 0.05) affected different genes and biological processes at different developmental ages. The number of DHA up-regulated DEGs was highest in 10 dph larvae (491), compared to 5 (12) and 15 dph fish (34), and were mainly involved in neural and synaptic development in the brain and spinal cord. In contrast, DHA in older 15 dph larvae elicited fewer DEGs but played critical roles over a wider range of developing organs. The emerging picture underscores the importance of DHA-modulated gene expression as a driving force in bluefin tuna larval development and growth.
本研究阐明了 DHA 调节基因在大西洋蓝鳍金枪鱼（Thunnus thynnus）幼虫发育和生长中的作用，这些幼虫通过摄食富含 DHA 的轮虫来获取 DHA。研究测试了低、中、高三种轮虫（Brachionus rotundiformis）DHA 水平（分别为 2.0、3.6 和 10.9 mg DHA g DW）对孵化后 2-15 天（dph）蓝鳍金枪鱼幼虫的影响。幼虫的 DHA 含量显著（P<0.05）呈 DHA 剂量依赖性增加（分别为 1.5、3.9、6.1 mg DHA g DW 幼虫），这与幼虫摄食和生长呈正相关（P<0.05）。差异表达基因（DEGs）的基因本体富集分析表明，膳食 DHA 显著（P<0.05）影响不同发育阶段的不同基因和生物学过程。在 10 dph 幼虫中，上调的 DHA DEGs 数量最高（491 个），而在 5（12）和 15 dph 鱼类中，上调的 DHA DEGs 数量分别为 34 个，这些基因主要涉及大脑和脊髓中的神经和突触发育。相比之下，在年龄较大的 15 dph 幼虫中，DHA 诱导的 DEGs 数量较少，但在更广泛的发育器官中发挥着关键作用。这一新兴图景强调了 DHA 调节基因表达作为蓝鳍金枪鱼幼虫发育和生长的驱动力的重要性。
