SRA

As economical traits, food habits domestication can reduce production cost in aquaculture. However, the molecular mechanism underlying food habits domestication has remained elusive. Mandarin fish (Siniperca chuatsi) only feed on live prey fish and refuse artificial diets. In the present study, we domesticated mandarin fish to feed on artificial diets. The two groups were obtained, the fish did not eat artificial diets or ate artificial diets during all of the three domestication processes, named Group W or X, respectively. Using transcriptome and metabolome analysis, we investigated the differentially expressed genes and metabolites between the two groups, and found three common pathways related to food habit domestication: retinol metabolism, glycerolipid metabolism, and biosynthesis of unsaturated fatty acids pathways. Furthermore, the western blot and bisulfite sequencing PCR analysis were performed. The histone methyltransferases EZH1 and TFIIF gene expression were significantly decreased and increased in fish of Group X, respectively. The total DNA methylation levels of TFIIF gene and tri-methylation of histone H3 at lysine 27 (H3K27me3) were significantly lower in mandarin of Group X. It was speculated that mandarin fish which could feed on artificial diets, might be contributed to the down-regulation of EZH1, resulting in decreased level of H3K27me3 and DNA methylation of TFIIF gene. The high expression of TFIIF gene, which might be a transcript factor to up-regulate the expression of genes in retinol metabolism, glycerolipid metabolism and glycerophosphoric metabolism. Our study could correlate the DNA and histone methylation with food habits domestication, which might be a novel molecular mechanism of food habits domestication in animals.