Transcriptome Analysis of Environmental Adaptation of Largemouth Bass (Micropterus salmonides)

The largemouth bass (Micropterus salmonides) is a farmed fish of significant economic value, and studying its adaptability is crucial for enhancing the economic benefits of aquaculture. The largemouth bass changes gene expression pattern to rapidly adapt to environmental changes and maintain normal physiological function.

In this study, largemouth bass from two distinct environmental backgrounds-Huzhou and Xingtai-were used as experimental materials, and they have significantly different breeding conditions. Comparative transcriptomics was used to analyze the gene expression patterns in largemouth bass from both backgrounds.

In the female, there were 1678 differentially expressed genes, of which 541 were upregulated and 1137 were downregulated. Meanwhile, in the male, there were 1287 differentially expressed genes, including 542 upregulated genes and 745 downregulated genes. The differentially expressed genes were mainly enriched in biological processes such as metabolic process, biological regulation, response to stimulus, developmental process, signaling, reproduction and immune system process. The enriched pathways included carbon metabolism, glycolysis/gluconeogenesis, purine metabolism, biosynthesis of amino acids, starch and sucrose metabolism, fructose and mannose metabolism, pyrimidine metabolism, MAPK signaling pathway, spliceosome, protein processing in the endoplasmic reticulum, ribosome biogenesis in eukaryotes, etc. Conclusions: We speculated that largemouth bass in Xingtai may adapt to the environment by downregulating metabolism- and reproduction-related genes and altering the expression of immune-related genes. Our study provided molecular evidence for the adaptation research of largemouth bass and provided a scientific basis for optimizing largemouth bass breeding technology.