Jin Nan, Wang Ling, Song Kai, Lu Kangle, Li Xueshan, Zhang Chunxiao
State Key Laboratory of Mariculture Breeding, Fisheries College, Jimei University, Xiamen 361021, China.
Xiamen Key Laboratory for Feed Quality Testing and Safety Evaluation, Fisheries College, Jimei University, Xiamen 361021, China.
Metabolites. 2024 Jul 25;14(8):406. doi: 10.3390/metabo14080406.
To analyze the potential mechanisms of growth differences in spotted seabass () fed a low-phosphorus diet, a total of 150 spotted seabass with an initial body weight of 4.49 ± 0.01 g were used (50 fish per tank) and fed a low-phosphorus diet for eight weeks. At the end of the experiment, five of the heaviest and five of the lightest fish were selected from each tank as fast-growing spotted seabass (FG) and slow-growing spotted seabass (SG), respectively, and their livers were analyzed by metabolomics and transcriptomics. The hepatic antioxidant capacity of the FG fed a low-phosphorus diet was significantly higher than that of the SG. A total of 431 differentially expressed genes (DEGs) were determined in the two groups, and most of the DEGs were involved in metabolism-related pathways such as steroid biosynthesis, glycolysis/gluconeogenesis, and protein digestion and absorption. Substance transport-related regulators and transporters were predominantly up-regulated. Furthermore, a large number of metabolites in the liver of FG were significantly up-regulated, especially amino acids, decanoyl-L-carnitine and dehydroepiandrosterone. The integration analysis of differential metabolites and genes further revealed that the interaction between protein digestion and absorption, as well as phenylalanine metabolism pathways were significantly increased in the liver of FG compared to those of the SG. In general, FG fed a low-phosphorus diet induced an enhancement in hepatic immune response, substance transport, and amino acid metabolism. This study provides new information on genetic mechanisms and regulatory pathways underlying differential growth rate and provides a basis for the foundation of efficient utilization of low-phosphorus diets and selective breeding programs for spotted seabass.
为分析投喂低磷饲料的花鲈生长差异的潜在机制，选取150尾初始体重为4.49±0.01 g的花鲈（每箱50尾），投喂低磷饲料8周。实验结束时，从每个水箱中分别选取5尾最重和5尾最轻的鱼作为快速生长花鲈（FG）和慢速生长花鲈（SG），并对它们的肝脏进行代谢组学和转录组学分析。投喂低磷饲料的FG肝脏抗氧化能力显著高于SG。两组共鉴定出431个差异表达基因（DEG），大多数DEG参与类固醇生物合成、糖酵解/糖异生以及蛋白质消化和吸收等代谢相关途径。物质运输相关调节因子和转运蛋白主要上调。此外，FG肝脏中的大量代谢物显著上调，尤其是氨基酸、癸酰-L-肉碱和脱氢表雄酮。差异代谢物和基因的整合分析进一步表明，与SG相比，FG肝脏中蛋白质消化和吸收以及苯丙氨酸代谢途径之间的相互作用显著增加。总体而言，投喂低磷饲料的FG诱导肝脏免疫反应、物质运输和氨基酸代谢增强。本研究为生长速率差异的遗传机制和调控途径提供了新信息，并为花鲈低磷饲料高效利用和选育计划的建立提供了依据。
