摘　要：同龄的黄颡鱼（Pelteobagrus fulvidraco）呈现明显的两性生长差异，即雄性个体的体长、体重皆大于雌性个体。而mTOR信号通路在细胞生长、发育以及蛋白合成过程中起重要作用。为了了解黄颡鱼两性差异的营养生长机制与mTOR信号通路之间的关联性，本试验首先在生理生化特性方面对雌、雄黄颡鱼的肌肉营养成分进行了比较分析。结果表明，在雌、雄黄颡鱼的比较分析中，除了两者的水分、粗蛋白、粗脂肪含量差别不大以外，在矿物元素、氨基酸组成、蛋白的氨基酸组成和脂肪酸组成等方面，雌性黄颡鱼肌肉的营养品质相对雄性更优。针对mTOR信号通路主要基因开展实时荧光定量PCR分析，结果显示，除性腺组织外，AKT1、AKT2、AKT3、mTOR、S6KA、S6KB、4E-BP1基因在雄性黄颡鱼的肌肉、肝、肾和心脏组织中的表达均显著高于雌性，这可能与雌雄黄颡鱼生长差异有关。本研究为进一步探索黄颡鱼两性生长差异的分子机制奠定了试验基础。
关键词：黄颡鱼；营养成分；生长差异；基因表达分析；mTOR信号通路
中图分类号：S965                          文献标志码：A                     DOI：10.3969/j.issn.1007-7146.2023.01.005

Abstract: There is a significant sex difference in the growth of yellow catfish (Pelteobagrus fulvidraco) at the same age which shows that males are longer in length and heavier in weight than females. mTOR (mechanistic target of rapamycin kinase) signaling pathway plays an important role in cell growth, development and protein synthesis. In order to understand the correlation between the nutritional growth mechanism of yellow catfish and the mTOR signaling pathway, this study firstly analyzed the muscle nutrient composition of female and male yellow catfish in the aspects of physiology and biochemistry. The results showed that the nutritional quality of female yellow catfish muscle was better than that of the wild female yellow catfish in terms of mineral elements, amino acid composition, protein evaluation and fatty acid quality, while there was little difference in water, crude protein and crude fat content between them. Quantitative real-time PCR (qRT-PCR) analysis was conducted for the major genes of mTOR signaling pathway. The results showed that the expressions of AKT serine/threonine kinase 1 (AKT1), AKT serine/threonine kinase 2 (AKT2), AKT serine/threonine kinase 3 (AKT3), mTOR, ribosomal protein S6 kinase B1 (S6KA), ribosomal protein S6 kinase B2 (S6KB), eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1) in muscle, liver, kidney and heart tissues of male yellow catfish were significantly higher than those of female. This may be related to the growth differences of female and male yellow catfish. These results provide an experimental basis for further exploring the molecular mechanism of sexual growth difference of yellow catfish.
Key words: Pelteobagrus fulvidraco; nutritional composition; growth difference; gene expression analysis; mTOR signaling pathway
（Acta Laser Biology Sinica, 2023, 32(1): 026-035）