Comparative Transcriptomic Profiling of Brain and Liver in Phoenix Barbs (Spinibarbus denticulatus denticulatus) with Differential Growth Rates

Phoenix barb (Spinibarbus denticulatus denticulatus) is a notable fish species in South China and is valued for its ecological and economic importance. To elucidate the molecular basis underlying its growth, we collected transcriptome profiles from the brains and livers of individual fish with different growth rates and compared differentially expressed genes (DEGs) at 3 and 9 months after hatching (MAH). Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that the pathways associated with growth were predominantly enriched in fatty acid biosynthesis, AMPK signaling, PI3K-Akt signaling, estrogen signaling, and protein metabolism. Notably, a greater number of DEGs from the fast-growing group were associated with these pathways at the early growth stage (3 MAH) than at the later stage (9 MAH). Real-time quantitative PCR results further validated that the genes involved in these pathways exhibited higher expression levels in fast-growing samples. This study enhances our understanding of the genetic mechanisms underlying growth rate differences and provides valuable genetic resources for future growth-related molecular breeding programs of phoenix barbs.