Transcriptome analysis of golden pompano (Trachinotus ovatus) liver indicates a potential regulatory target involved in HUFA uptake and deposition

• Published in: Comparative biochemistry and physiology. Part D, Genomics & proteomics Vol. 33; p. 100633
• Main Authors: Lei, Cai-xia, Li, Meng-meng, Tian, Jing-jing, Wen, Ji-kai, Li, Yuan-you
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 01.03.2020
• Subjects: Animals; Fatty Acids, Unsaturated - genetics; Fatty Acids, Unsaturated - metabolism; Fish Proteins - genetics; Fish Proteins - metabolism; Fishes - genetics; Fishes - metabolism; Gene Expression Profiling; Highly unsaturated fatty acid; Liver - metabolism; RNA-seq; Signal Transduction; Trachinotus ovatus; Transcriptome; Uptake and deposition; ACOT8; Trachinotus ovatus; CYP46A; PUFA; AKR1D1; MUFA; FABP; Highly unsaturated fatty acid; HUFA; CYP7A1; CYP8B1; Uptake and deposition; FAT/CD36; SFA; CYP27A1; CH25H; RNA-seq; PPAR; PPRE; EPA; FATP; DHA
• ISSN: 1744-117X; 1878-0407
• DOI: 10.1016/j.cbd.2019.100633

Promoting highly unsaturated fatty acid (HUFA) uptake and deposition can improve nutritional value of farmed fish and reduce dietary fish oil addition. Previously, we found that the golden pompano Trachinotus ovatus liver HUFA content increased with the increasing of dietary HUFA. Therefore, we examined the common genes and pathways responsible for HUFA uptake and deposition in T. ovatus liver using transcriptome sequencing technology after feeding with either 1.0% or 2.1% HUFA for 8 weeks. Results showed that a total of 140 and 147 genes were significantly upregulated and downregulated, respectively. Five bile acid synthesis-related genes (CYP7A1, CYP8B1, AKR1D1, SCP2 and ACOT8), which are related to dietary fat emulsification were downregulated in 2.1% HUFA group, implying that the cholate synthesized through the classical pathway might be the main bile acid form in fat emulsification. Moreover, fatty acid transport protein (FATP)-6, fatty acid binding protein (FABP)-1, -4, and -6 increased with HUFA deposition, especially FATP6 and FABP4, suggesting that the two genes may be important mediators involved in HUFA uptake and deposition. KEGG analysis showed that most of the differential genes described above were involved in peroxisome proliferator activator receptor (PPAR) signaling pathway, and PPARγ increased with HUFA deposition, indicating that PPARγ might be a key regulator of HUFA uptake and deposition by regulating the genes involved in fatty acid emulsification and transport. This study focused on the liver, which is the center of intermediary metabolism, providing a comprehensive understanding of the molecular regulation of HUFA uptake and deposition in T. ovatus, which should be further investigated to develop potential measures to improve HUFA content. •Promoting HUFA deposition can improve nutritional value of farmed fish, and reduce dietary fish oil level.•Nine candidate genes involved in HUFA deposition were identified.•PPARγ plays an important role in promoting HUFA deposition by regulating related genes.•Common genes and pathways responsible for HUFA deposition were investigated.