title: Analysis of porcine adipose tissue transcriptome reveals differences in de novo fatty acid synthesis in pigs with divergent muscle fatty acid composition.
abstract: BACKGROUND
  In pigs, adipose tissue is one of the principal organs involved in the regulation of lipid metabolism. It is particularly 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).
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Centre de Recerca en Agrigenòmica (Consorci CSIC-IRTA-UAB-UB), Edifici CRAG, Campus UAB, Bellaterra, 08193 Barcelona, Spain. jordi.corominas@uab.cat.
authors.forename: Jordi
authors.initials: J
authors.lastname: Corominas
authors.forename: Yuliaxis
authors.initials: Y
authors.lastname: Ramayo-Caldas
authors.forename: Anna
authors.initials: A
authors.lastname: Puig-Oliveras
authors.forename: Jordi
authors.initials: J
authors.lastname: Estellé
authors.forename: Anna
authors.initials: A
authors.lastname: Castelló
authors.forename: Estefania
authors.initials: E
authors.lastname: Alves
authors.forename: Ramona N
authors.initials: RN
authors.lastname: Pena
authors.forename: Maria
authors.initials: M
authors.lastname: Ballester
authors.forename: Josep M
authors.initials: JM
authors.lastname: Folch
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D000818:Animals; D004251:DNA Transposable Elements; D005227:Fatty Acids / Q000096:biosynthesis*; D005260:Female; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D053263:Gene Regulatory Networks; D055106:Genome-Wide Association Study; D050356:Lipid Metabolism; D008297:Male; D053858:Metabolic Networks and Pathways; D058977:Molecular Sequence Annotation; D018482:Muscle, Skeletal / Q000378:metabolism; D009132:Muscles / Q000378:metabolism*; D016366:Open Reading Frames; D010641:Phenotype; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013552:Swine; D059467:Transcriptome
chemical_list: D004251:DNA Transposable Elements; D005227:Fatty Acids; D012333:RNA, Messenger