Comprehensive evaluation of the metabolic effects of porcine CRTC3 overexpression on subcutaneous adipocytes with metabolomic and transcriptomic analyses

Abstract

Background Meat quality is largely driven by fat deposition, which is regulated by several genes and signaling pathways. The cyclic adenosine monophosphate (cAMP) -regulated transcriptional coactivator 3 (CRTC3) is a coactivator of cAMP response element binding protein (CREB) that mediates the function of protein kinase A (PKA) signaling pathway and is involved in various biological processes including lipid and energy metabolism. However, the effects of CRTC3 on the metabolome and transcriptome of porcine subcutaneous adipocytes have not been studied yet. Here, we tested whether porcine CRTC3 expression would be related to fat deposition in Heigai pigs (a local fatty breed in China) and Duroc×Landrace×Yorkshire (DLY, a lean breed) pigs in vivo. The effects of adenovirus-induced CRTC3 overexpression on the metabolomic and transcriptomic profiles of subcutaneous adipocytes were also determined in vitro by performing mass spectrometry-based metabolomics combined with RNA sequencing (RNA-seq). Results Porcine CRTC3 expression is associated with fat deposition in vivo. In addition, CRTC3 overexpression increased lipid accumulation and the expression of mature adipocyte-related genes in cultured porcine subcutaneous adipocytes. According to the metabolomic analysis, CRTC3 overexpression induced significant changes in adipocyte lipid, amino acid and nucleotide metabolites in vitro. The RNA-seq analysis suggested that CRTC3 overexpression alters the expression of genes and pathways involved in adipogenesis, fatty acid metabolism and glycerophospholipid metabolism in vitro. Conclusions We identified significant alterations in the metabolite composition and the expression of genes and pathways involved in lipid metabolism in CRTC3-overexpressing adipocytes. Our results suggest that CRTC3 might play an important regulatory role in lipid metabolism and thus affects lipid accumulation in porcine subcutaneous adipocytes.

CRTC3 Regulates the Lipid Metabolism and Adipogenic Differentiation of Porcine Intramuscular and Subcutaneous Adipocytes by Activating the Calcium Pathway

“…For mice, a previous study demonstrated that overexpression of CRTC3 increased the intramuscular TGs level in skeletal muscle cells, which was consistent with our results. Our recent study provides a comprehensive resource describing the transcriptomic and metabolomic impacts of CRTC3 overexpression in porcine SC adipocytes . In this study, we found that various amino acid, lipid, carbohydrate, nucleotide, vitamin metabolism, and TCA cycle metabolic pathways were affected.…”

“…19,20 Furthermore, adenovirusmediated CRTC3 overexpression alters metabolite composition and the expression of genes and pathways in CRTC3overexpressing SC adipocytes. 21 However, the regulatory roles and metabolic effects of CRTC3 in porcine IM adipocytes are not understood. Furthermore, the effect and regulatory mechanism of CRTC3 on porcine adipocytes are still unknown.…”

“…CRTC3 overexpression altered GP metabolism and promoted lipid accumulation in both IM and SC adipocytes (Figure F and Figure S4A,B). To determine whether CRTC3 regulates lipid accumulation and metabolism through different regulatory pathways in IM and SC adipocytes, a Venn diagram was used to visualize the shared or specific DEGs that were altered in IM or SC adipocytes (Figure A) . We found that 192 upregulated DEGs and 129 downregulated DEGs were specific to SC adipocytes (Figure A), and 1417 upregulated DEGs and 1798 downregulated DEGs were found in CRTC3-overexpressing IM adipocytes compared with SC adipocytes (Figure A).…”

“…To determine whether CRTC3 regulates lipid accumulation and metabolism through different regulatory pathways in IM and SC adipocytes, a Venn diagram was used to visualize the shared or specific DEGs that were altered in IM or SC adipocytes (Figure 4A). 21 We found that 192 upregulated DEGs and 129 downregulated DEGs were specific to SC adipocytes (Figure 4A), and 1417 upregulated DEGs and 1798 downregulated DEGs were found in CRTC3overexpressing IM adipocytes compared with SC adipocytes (Figure 4A). Notably, the specific upregulated DEGs in CRTC3-overexpressing IM adipocytes were enriched in oxidative phosphorylation, transcriptional activity-related spliceosome, RNA transport, and RNA polymerase pathways (Figure 4B).…”

“…In our previous studies, we cloned the sequence of porcine CRTC3 and found that the expression of CRTC3 is associated with the IMF deposition in pigs. , Furthermore, adenovirus-mediated CRTC3 overexpression alters metabolite composition and the expression of genes and pathways in CRTC3-overexpressing SC adipocytes . However, the regulatory roles and metabolic effects of CRTC3 in porcine IM adipocytes are not understood.…”