Page 15 - 《渔业研究》2026年第2期

158 渔 业 研 究 第 48 卷

Cloning and nutritional regulation analysis of the G-protein-coupled
receptor 43 (GPR43) gene in Trachinotus ovatus

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YU Na ，CHEN Yaqi ，LI Yuhao ，WANG Minghao ，ZHONG Yong ，
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XUN Pengwei ，LI Tao ，YU Dapeng ，CAI Jia 1,2*
(1. College of Fisheries, Guangdong Ocean University/Guangdong Provincial Laboratory of Southern Marine Science and
Engineering/Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture/Zhanjiang Key Laboratory
of Marine Ecology and Aquaculture Environment, Zhanjiang 524008, China;
2. Shenzhen Institute of Guangdong Ocean University, Shenzhen 518200, China;
3. School of Fisheries, Xinyang Agriculture and Forestry University, Xinyang 464000, China;
4. Shenzhen Experimental Base, South China Sea Fisheries Research Institute,
Chinese Academy of Fisheries Sciences, Shenzhen 518200, China)
Abstract: [Background] Trachinotus ovatus is a tropical-subtropical marine fish species. In recent years, the
aquaculture industry of T. ovatus in China has developed rapidly, with key breakthroughs in breeding and cultiv-
ation technologies. However, with the expansion of aquaculture scale and the subsequent increase in feed de-
mand, optimizing feed formulations to reduce production costs has become a crucial approach for enhancing
economic returns. [Objective] This study aims to investigate the role of G-protein-coupled receptor 43
(GPR43) gene in energy metabolism in T. ovatus. [Methods] Primers were designed based on the GPR43 gene
sequence to identify homologs and clone the coding sequence (CDS). Bioinformatics analysis was subsequently
employed to investigate the structural characteristics of the gene and its encoded protein. To further elucidate the
functional roles, both in vivo and in vitro experiments were conducted. In vivo, the expression levels of GPR43
gene in ten different tissues of T. ovatus were detected using quantitative real-time polymerase chain reaction
(qRT-PCR). Furthermore, the effects of high-sugar feeding and starvation on the expression of this gene in liver
and muscle tissues were analyzed. In vitro studies involved isolating primary hepatocytes from T. ovatus liver,
which were then subjected to high-sugar and starvation treatments to assess their impact on gene expression.
[Results] The CDS of T. ovatus GPR43 gene was 1 011 bp, encoding 336 amino acids, that form a receptor
specifically recognizing short-chain fatty acids. Protein structure analysis revealed that T. ovatus GPR43 protein
contains seven transmembrane domains. Homology analysis indicated that T. ovatus GPR43 gene shared high
homology with GPR43 gene of the same species (amino acid similarity>86%) and was most closely related to T.
anak. In contrast, its homology with mammals was relatively low (amino acid similarity was 50%). Tissue dis-
tribution analysis showed that GPR43 gene expression was the highest in the liver, followed by the intestine,
brain, and muscle, and the lowest in the skin. In vivo results demonstrated that GPR43 gene expression in the
liver and muscle of fish fed a high-glucose diet was lower than that in the starvation group. Similarly, in vitro
experiments showed that GPR43 gene expression in primary hepatocytes treated with high glucose was lower
compared to the starvation group, consistent with the in vivo trend. [Conclusion] The results demonstrate that
the expression levels of GPR43 gene in the liver and the muscle of T. ovatus are significantly modulated by diet-
ary carbohydrate levels. These findings suggest that GPR43 gene plays a crucial role in sensing energy status
and regulating lipid metabolism, thereby serving as a potential biomarker for energy homeostasis in this species.
The present study provides valuable insights for reducing feeding costs, controlling body fat content, and im-
proving flesh quality in T. ovatus aquaculture.
Key words: Trachinotus ovatus; GPR43 gene; sequence analysis; tissue distribution; nutritional regulation