Comparative analysis of gene expression profiles in differentiated subcutaneous adipocytes between Jiaxing Black and Large White pigs

Abstract

Background Chinese domestic pig breeds are reputed for pork quality, but their low ratio of lean-to-fat carcass weight decreases production efficiency. A better understanding of the genetic regulation network of subcutaneous fat tissue is necessary for the rational selection of Chinese domestic pig breeds. In the present study, subcutaneous adipocytes were isolated from Jiaxing Black pigs a Chinese indigenous pig breed with redundant subcutaneous fat deposition and Large White pigs a lean-type pig breed with relatively low subcutaneous fat deposition. The expression profiles of mRNAs and lncRNAs were compared by RNA-seq analysis to identify biomarkers correlated with the differences of subcutaneous fat deposition between the two breeds. Results A total of 1058 differentially expressed genes and 221 differentially expressed lncRNAs were identified in subcutaneous adipocytes between Jiaxing Black and Large White pigs, which included 275 up-regulated mRNAs, 783 down-regulated mRNAs, 118 up-regulated lncRNAs and 103 down-regulated lncRNAs. Gene Ontology and KEGG pathway enrichment analyses revealed that the differentially expressed genes and differentially expressed lncRNAs were mainly involved in the immune response, cell fate determination, PI3K-Akt signaling pathway and MAPK signaling pathway, which are known to be related to adipogenesis and lipid metabolism. The expression levels of differentially expressed genes and differentially expressed lncRNAs according to the RNA-seq data were verified by quantitative PCR, which showed 81.8% consistency. The differences in MAPK pathway activity between Jiaxing Black and Large White pigs was confirmed by western blot analysis, which revealed elevated p38 phosphorylation in Jiaxing Black pigs. Conclusions This study offers a detailed characterization of mRNAs and lncRNAs in fat- and lean-type pig breeds. The activity of the MAPK signaling pathway was found to be associated with subcutaneous adipogenesis. These results provide new targets for further investigation of the molecular mechanisms regulating subcutaneous fat deposition in pigs.

Genome-wide association study identifying genetic variants associated with carcass backfat thickness, lean percentage and fat percentage in a four-way crossbred pig population using SLAF-seq technology

“…GO annotation result showed that GRM4 was involved in activation of MAPK activity (Table S 4 ). The MAPK pathway was demonstrated in numerous studies to be crucial for adipogenesis [ 54 , 55 ]. So GRM4 might play an important role in adipogenesis by activation of MAPK activity.…”

Genome-Wide Association Study of Growth Traits in a Four-Way Crossbred Pig Population

“…The Ras-MAPK signaling pathway can control cell proliferation, differentiation, and survival through the kinase cascade [ 72 , 73 , 74 ]. Many studies have shown that Ras-MAPK signaling pathway is crucial for adipogenesis [ 75 , 76 ]. Therefore, it could be inferred that BRAP gene might regulate fat deposition in pigs through Ras-MAPK signal pathway, thereby affecting average daily gain of pigs.…”

Screening candidate genes related to psoas muscle traits in Debao and Landrace pigs based on transcriptome analysis

“…FOS is an inflammatory and apoptosis-related gene [20][21], and in recent years, studies have reported that FOS may be related to pig muscle growth weight [22]. Studies have also shown that EGR1 is an early growth response protein, which has an important relationship with cell proliferation, differentiation and apoptosis, Egr1 expression is activated by a variety of MAPK-inducing factors [23][24][25], Multiple studies have shown that the MAPK pathway regulates the expression of adipogenesis transcription factors during adipogenesis [26][27]. EGR1 knockout in mice can reduce leptin expression in basal cells [28].…”