Abstract:To explore the unique aquatic germplasm resources in the Mudanjiang region, this study compares the morphology and key flavor genes of wild grass carp from Jingpo Lake and commercially farmed grass carp. Grass carp with no significant differences in body weight were selected for morphological measurements, and their dorsal muscles were sampled for transcriptome sequencing analysis. The results showed that compared to commercial grass carp, Jingpo Lake grass carp had a more elongated body shape, a viscerosomatic ratio of 7.68% (significantly lower, P<0.01), and a gutted body ratio of 92.32% (significantly higher, P<0.05). Transcriptome sequencing yielded 40.38 Gb of filtered data, revealing 1,587 differentially expressed genes: 527 upregulated and 1,060 downregulated, showing high similarity between samples. KEGG enrichment analysis identified 183 signaling pathways, screening for flavor-related regulatory genes. Genes AK4 and AMPD1 were found to play important roles in inosine monophosphate (IMP) synthesis; FASN, LPL, PLIN2, ACOX1, and FABP1a are involved in regulating intramuscular fat (IMF) accumulation; BCAT1, BCAT2, and DDO are key to the generation of flavor amino acids. In summary, Jingpo Lake grass carp have a higher edible portion and less abdominal fat accumulation, with the expression of flavor-related genes being the main reason for their unique flavor. This study provides a theoretical basis for the development and application of grass carp resources in the volcanic barrier lake system of the Mudanjiang region.
