ABSTRACT: Analysis of porcine adipose tissue transcriptome reveals differences in de novo fatty acid synthesis in pigs with divergent muscle fatty acid composition
Project description:In pigs, adipose tissue is one of the principal organs involved in the regulation of lipid metabolism. It is particulary involved in the overall fatty acid synthesis with consequences in other lipid-target organs such as muscles and the liver. With this in mind, we have used massive, parallel high-throughput sequencing technologies to characterize the porcine adipose tissue transcriptome architecture in six Iberian x Landrace crossbred pigs showing extreme phenotypes for intramuscular fatty acid composition (three per group). High-throughput RNA sequencing was used to generate a whole characterization of adipose tissue (backfat) transcriptome. A total of 4,130 putative unannotated protein-coding sequences were identified in the 20% of reads which mapped in intergenic regions. Furthermore, 36% of the unmapped reads were represented by interspersed repeats, SINEs being the most abundant elements. Differential expression analyses identified 396 candidate genes among divergent animals for intramuscular fatty acid composition. Sixty-two percent of these genes (247/396) presented higher expression in the group of pigs with higher content of intramuscular SFA and MUFA, while the remaining 149 showed higher expression in the group with higher content of PUFA. Pathway analysis related these genes to biological functions and canonical pathways controlling lipid and fatty acid metabolisms. In concordance with the phenotypic classification of animals, the major metabolic pathway differentially modulated between groups was de novo lipogenesis, the group with more PUFA being the one that showed lower expression of lipogenic genes. These results will help in the identification of genetic variants at loci that affect fatty acid composition traits. The implications of these results range from the improvement of porcine meat quality traits to the application of the pig as an animal model of human metabolic diseases. The supplementary files contains the five arrays reported in the paper. Backfat from five animals were assayed with high-density oligonucleotide microarray chips (GeneChipM-BM-. Porcine) from Affymetrix, in order to validate RNA-Seq data.
Project description:In pigs, adipose tissue is one of the principal organs involved in the regulation of lipid metabolism. It is particulary involved in the overall fatty acid synthesis with consequences in other lipid-target organs such as muscles and the liver. With this in mind, we have used massive, parallel high-throughput sequencing technologies to characterize the porcine adipose tissue transcriptome architecture in six Iberian x Landrace crossbred pigs showing extreme phenotypes for intramuscular fatty acid composition (three per group). High-throughput RNA sequencing was used to generate a whole characterization of adipose tissue (backfat) transcriptome. A total of 4,130 putative unannotated protein-coding sequences were identified in the 20% of reads which mapped in intergenic regions. Furthermore, 36% of the unmapped reads were represented by interspersed repeats, SINEs being the most abundant elements. Differential expression analyses identified 396 candidate genes among divergent animals for intramuscular fatty acid composition. Sixty-two percent of these genes (247/396) presented higher expression in the group of pigs with higher content of intramuscular SFA and MUFA, while the remaining 149 showed higher expression in the group with higher content of PUFA. Pathway analysis related these genes to biological functions and canonical pathways controlling lipid and fatty acid metabolisms. In concordance with the phenotypic classification of animals, the major metabolic pathway differentially modulated between groups was de novo lipogenesis, the group with more PUFA being the one that showed lower expression of lipogenic genes. These results will help in the identification of genetic variants at loci that affect fatty acid composition traits. The implications of these results range from the improvement of porcine meat quality traits to the application of the pig as an animal model of human metabolic diseases. The supplementary files contains the five arrays reported in the paper.
Project description:Breed, gender and diet are factors affecting porcine metabolism. The aim of this study has been to investigate the gene expression patterns of the major sites for lipid metabolism, liver and fat, conditional on gender and on a moderate feeding restriction in Iberian pigs, as a model of obese porcine breed. Our results show that tissue effect account for more differentially expressed genes than gender or feeding restriction. The results obtained from the comparison between tissues support the studies showing adipose tissue is not only a fat-storage depot, we report a high number of upregulated genes in adipose tissue which represent relevant biological functions such as carbohydrate and energy metabolisms and endocrine function. Besides, key genes implicated in lipid metabolism are specifically overrepresented in liver or fat, particularly the differentially expressed genes related to fatty acid synthesis support previous studies showing that in pig, as in cattle or sheep, this process largely occurs in fat. We identified metabolic differences between genders such as oxidation capacity or response to toxins, reflected at gene expression level in liver but no in adipose tissue, contrarily to previous studies. Finally, our results seem to indicate that a moderate feeding restriction does not have large effects on liver or fat gene expression of obese pigs. Although the list of differentially expressed genes due to the effect of feeding restriction is limited, we could identify expression differences in genes related to antiageing mechanisms associated with feeding restriction as enhancement of immune response and anticoagulation and the balance between prosurvival and cell-death. Breed, gender and diet are factors affecting porcine metabolism. The aim of this study has been to investigate the gene expression patterns of the major sites for lipid metabolism, liver and fat, conditional on gender and on a moderate feeding restriction in Iberian pigs, as a model of obese porcine breed. Our results show that tissue effect account for more differentially expressed genes than gender or feeding restriction. The results obtained from the comparison between tissues support the studies showing adipose tissue is not only a fat-storage depot, we report a high number of upregulated genes in adipose tissue which represent relevant biological functions such as carbohydrate and energy metabolisms and endocrine function. Besides, key genes implicated in lipid metabolism are specifically overrepresented in liver or fat, particularly the differentially expressed genes related to fatty acid synthesis support previous studies showing that in pig, as in cattle or sheep, this process largely occurs in fat. We identified metabolic differences between genders such as oxidation capacity or response to toxins, reflected at gene expression level in liver but no in adipose tissue, contrarily to previous studies. Finally, our results seem to indicate that a moderate feeding restriction does not have large effects on liver or fat gene expression of obese pigs. Although the list of differentially expressed genes due to the effect of feeding restriction is limited, we could identify expression differences in genes related to antiageing mechanisms associated with feeding restriction as enhancement of immune response and anticoagulation and the balance between prosurvival and cell-death. 16 liver and subcutaneous backfat samples from eight animals at slaughter, 211 days old, four males and four females, four under high feeding level and four under 20% restriction
Project description:Cystic fibrosis (CF) mouse models exhibit exocrine pancreatic function yet do not develop adipose stores to the levels of non-CF mice. CF mice homozygous for the Cftr mutation (F508del) at 3 weeks (post-weaning) and 6 weeks (young adult) of age had markedly less adipose tissue than non-CF mice. Both 3- and 6-week old mice had dietary lipid absorption and fecal lipid excretion comparable to non-CF controls. Fractional hepatic de novo synthesis of palmitate and stearate (de novo lipogenesis, DNL) as determined by deuterium incorporation was reduced in CF mice. At 3 weeks of age, F508del mice had significantly decreased DNL of palmitate and stearate, by 83% and 80%, respectively. By 6 weeks of age, DNL rates in non-CF mice remained unchanged as compared to 3-week old mice, while DNL rates of F508del mice were still reduced, by 33% and 40%, respectively. Adipose tissue fatty acid profiles were comparable in CF and non-CF mice, indicating that adipose differences are quantitative, not qualitative. A correspondingly lower content of deuterium-labeled fatty acids was found in CF adipose tissue, consistent with reduced deposition of newly made hepatic triglycerides and/or decreased adipose tissue lipogenesis. Hepatic transcriptome analysis revealed lower mRNA expression from several genes involved in fatty acid biosynthesis, suggesting down-regulation of several enzymes in fatty acids synthesis as a mechanism for the reduced lipogenesis. These novel data provide a model for altered fat and fatty acid metabolism in CF, independent of malabsorption, and may partly explain the inability of pancreatic enzyme replacement therapy to completely restore normal body mass to CF patients ∆F508 CF mice and its WT littermates (3-weeks old females, C57BL/6J) were examined. RNA extracted from snapped-frozen livers, 4 replicates per genotype.
Project description:Breed, gender and diet are factors affecting porcine metabolism. The aim of this study has been to investigate the gene expression patterns of the major sites for lipid metabolism, liver and fat, conditional on gender and on a moderate feeding restriction in Iberian pigs, as a model of obese porcine breed. Our results show that tissue effect account for more differentially expressed genes than gender or feeding restriction. The results obtained from the comparison between tissues support the studies showing adipose tissue is not only a fat-storage depot, we report a high number of upregulated genes in adipose tissue which represent relevant biological functions such as carbohydrate and energy metabolisms and endocrine function. Besides, key genes implicated in lipid metabolism are specifically overrepresented in liver or fat, particularly the differentially expressed genes related to fatty acid synthesis support previous studies showing that in pig, as in cattle or sheep, this process largely occurs in fat. We identified metabolic differences between genders such as oxidation capacity or response to toxins, reflected at gene expression level in liver but no in adipose tissue, contrarily to previous studies. Finally, our results seem to indicate that a moderate feeding restriction does not have large effects on liver or fat gene expression of obese pigs. Although the list of differentially expressed genes due to the effect of feeding restriction is limited, we could identify expression differences in genes related to antiageing mechanisms associated with feeding restriction as enhancement of immune response and anticoagulation and the balance between prosurvival and cell-death. Breed, gender and diet are factors affecting porcine metabolism. The aim of this study has been to investigate the gene expression patterns of the major sites for lipid metabolism, liver and fat, conditional on gender and on a moderate feeding restriction in Iberian pigs, as a model of obese porcine breed. Our results show that tissue effect account for more differentially expressed genes than gender or feeding restriction. The results obtained from the comparison between tissues support the studies showing adipose tissue is not only a fat-storage depot, we report a high number of upregulated genes in adipose tissue which represent relevant biological functions such as carbohydrate and energy metabolisms and endocrine function. Besides, key genes implicated in lipid metabolism are specifically overrepresented in liver or fat, particularly the differentially expressed genes related to fatty acid synthesis support previous studies showing that in pig, as in cattle or sheep, this process largely occurs in fat. We identified metabolic differences between genders such as oxidation capacity or response to toxins, reflected at gene expression level in liver but no in adipose tissue, contrarily to previous studies. Finally, our results seem to indicate that a moderate feeding restriction does not have large effects on liver or fat gene expression of obese pigs. Although the list of differentially expressed genes due to the effect of feeding restriction is limited, we could identify expression differences in genes related to antiageing mechanisms associated with feeding restriction as enhancement of immune response and anticoagulation and the balance between prosurvival and cell-death.
Project description:Cystic fibrosis (CF) mouse models exhibit exocrine pancreatic function yet do not develop adipose stores to the levels of non-CF mice. CF mice homozygous for the Cftr mutation (F508del) at 3 weeks (post-weaning) and 6 weeks (young adult) of age had markedly less adipose tissue than non-CF mice. Both 3- and 6-week old mice had dietary lipid absorption and fecal lipid excretion comparable to non-CF controls. Fractional hepatic de novo synthesis of palmitate and stearate (de novo lipogenesis, DNL) as determined by deuterium incorporation was reduced in CF mice. At 3 weeks of age, F508del mice had significantly decreased DNL of palmitate and stearate, by 83% and 80%, respectively. By 6 weeks of age, DNL rates in non-CF mice remained unchanged as compared to 3-week old mice, while DNL rates of F508del mice were still reduced, by 33% and 40%, respectively. Adipose tissue fatty acid profiles were comparable in CF and non-CF mice, indicating that adipose differences are quantitative, not qualitative. A correspondingly lower content of deuterium-labeled fatty acids was found in CF adipose tissue, consistent with reduced deposition of newly made hepatic triglycerides and/or decreased adipose tissue lipogenesis. Hepatic transcriptome analysis revealed lower mRNA expression from several genes involved in fatty acid biosynthesis, suggesting down-regulation of several enzymes in fatty acids synthesis as a mechanism for the reduced lipogenesis. These novel data provide a model for altered fat and fatty acid metabolism in CF, independent of malabsorption, and may partly explain the inability of pancreatic enzyme replacement therapy to completely restore normal body mass to CF patients
Project description:Intramuscular fat (IMF) content is an important trait closely correlated with meat quality, which is highly variable among swine breeds from diverse genetic backgrounds. In order to elucidate the molecular mechanism underlying porcine meat quality, we adopted RNA-sequencing to detect transcriptome in the longissimus dorsi muscle of Wei pigs (a Chinese indigenous breed) and Yorkshire pigs (a Western lean-type breed) with different IMF content. A total of 717 differentially expressed genes (DEGs) were identified in our study, with 323 up-regulated and 394 down-regulated genes in Wei pigs compared with Yorkshire pigs. GO analysis showed that DEGs significantly related to muscle proliferation and development, lipid storage and catabolic, extracellular matrix structural constituent, and neutral amino acid transmembrane transporter activity. Pathway analysis revealed that DEGs associated with fatty acid metabolism, steroid biosynthesis, glycerophospholipid metabolism, protein digestion and absorption, and amino acid metabolism. Quantitative real time PCR confirmed the differential expression of 11 selected DEGs from both pig breeds. The results provide useful information to investigate the transcriptional profiling in skeletal muscle of different pig breeds with divergent phenotypes, and several DEGs can be taken as functional candidate genes for affecting pork quality.
Project description:Purpose: Identification of genes regulating growth and fatness traits in pig. Methods: Hypothalamic transcriptome analysis through RNA-seq and differential expression analysis of divergent pigs for growth and fatness traits. Results: Characterization of the transcripts expressed in the porcine hypothalamus and identification of differentially expressed genes, some of them located within previously described QTL regions. Conclusions: Characterization of porcine hypothalamic transcriptome and identification of relevant genes and transcription factors related to the traits of interest. Transcriptome sequencing of 10 hypothamic samples of two groups of divergent pigs for growth and fatness (five per group).
Project description:Regulatory Mechanisms of Atrial Remodeling of Mitral Regurgitation Pigs This study enrolled 6 pigs (age: 18 months) and divided into three groups: mitral regurgitation pigs (MR) (n = 2; 2 males sacrificed 12 months after surgery), MR pigs treated with valsartan (MRV) (n = 2; 2 males age-matched to MR sacrificed 12 months after surgery), and normal control pigs (NC) (n = 2; 2 males age-matched to MR pigs). Valsartan (3.43 mg/kg/day), a type I angiotensin II receptor blocker, was administered from one week before surgery and then daily after surgery in the MRV group. We sought to systemically elucidate critical differences in the alteration of RNA expression pattern between the atrial myocardium of pigs with and without MR, and between the atrial myocardium of MR pigs with and without valsartan using high-density oligonucleotide microarrays and functional network enrichment analysis.
Project description:Arabidopsis seeds expressing the castor fatty acid hydroxylase accumulate hydroxylated fatty acids up to 17% of total fatty acids in seed triacylglycerols, however total seed oil is also reduced up to 50%. Investigations into the cause of the reduced oil phenotype through in vivo [14C]acteate and [3H]2O metabolic labeling of developing seeds surprisingly revealed that the rate of de novo fatty acid synthesis within the transgenic seeds was approximately half that of control seeds. Addition of castor phospholipid:diacylglycerol acyltransferase (PDAT) increased hydroxylated fatty acid content of the seed oil, increased the rate of fatty acid synthesis, and mostly restored seed oil levels. RNAseq analysis indicated no changes in expression of fatty acid synthesis genes in hydroxylase-expressing plants. Transcript profiles of Arabidopsis developing seeds of three lines, at three stages of development were generated by deep sequencing, in triplicate, using Illumina.