Aquaculture Reports (Dec 2024)
Comparative transcriptomes and metabolome reveal heterosis in zig zag eel (Mastacembelus armatus)
Abstract
In the process of artificial breeding, due to the lack of rigorous and standardized screening and cultivation of parent fish, the quality of M. armatus' seedlings had sharply declined, seriously affecting the sustainable and healthy development of the artificial breeding industry of M. armatus. Therefore, we set up four breeding combinations (HH, Huizhou ♂ x Huizhou ♀; KK, Kaiping ♂ x Kaiping ♀; HK, Huizhou ♂ x Kaiping ♀; KH, Kaiping ♂ x Huizhou ♀) to study the effect of hybridization on the growth performance of M. armatus. After hatching, the juvenile fish were continuously farmed for 180 days, and their total length and weight were measured every 60 days. Liver tissues from various combinations were collected for transcriptome and metabolomic analysis. Compared with the HH combination and the KK combination, the total length and weight of individuals in the HK combination and the KH combination were significantly increased, and the expression levels of GH in brain tissue and GH, IGF-Ⅰ in muscle tissue were significantly up-regulated. Transcriptome analysis showed that the growth of individuals in the dominant hybrid combination (HK combination) was related to genes such as SCD, FASN, PPARα, ACO, etc. in the lipid metabolism pathways. Metabolomic analysis showed that the glycerol content in the HK combination was significantly lower than that in the KK combination. The combined analysis of transcriptome and metabolome showed that hybrid advantage was well demonstrated in the lipid metabolism pathways, and high expression of PPARα could promote the expression of AQP9 protein, further promoting the liver's uptake and metabolism of glycerol. The research results indicated that individuals in the HK combination had higher lipid synthesis and metabolic ability, and one of the hybrid advantages of M. armatus was its efficient utilization of glycerol.
