Puig-Oliveras Anna, Ramayo-Caldas Yuliaxis, Corominas Jordi, Estellé Jordi, Pérez-Montarelo Dafne, Hudson Nicholas J, Casellas Joaquim, Folch Josep M, Ballester Maria
Departament de Genètica Animal, Centre de Recerca en Agrigenòmica (CRAG), Bellaterra, Spain; Departament de Ciència Animal i dels Aliments, Universitat Autònoma de Barcelona (UAB), Bellaterra, Spain.
Génétique Animale et Biologie Intégrative UMR1313 (GABI), Institut National de la Recherche Agronomique (INRA), Jouy-en-Josas, France.
PLoS One. 2014 Jun 13;9(6):e99720. doi: 10.1371/journal.pone.0099720. eCollection 2014.
Besides having an impact on human health, the porcine muscle fatty acid profile determines meat quality and taste. The RNA-Seq technologies allowed us to explore the pig muscle transcriptome with an unprecedented detail. The aim of this study was to identify differentially-expressed genes between two groups of 6 sows belonging to an Iberian × Landrace backcross with extreme phenotypes according to FA profile.
We sequenced the muscle transcriptome acquiring 787.5 M of 75 bp paired-end reads. About 85.1% of reads were mapped to the reference genome. Of the total reads, 79.1% were located in exons, 6.0% in introns and 14.9% in intergenic regions, indicating expressed regions not annotated in the reference genome. We identified a 34.5% of the intergenic regions as interspersed repetitive regions. We predicted a total of 2,372 putative proteins. Pathway analysis with 131 differentially-expressed genes revealed that the most statistically-significant metabolic pathways were related with lipid metabolism. Moreover, 18 of the differentially-expressed genes were located in genomic regions associated with IMF composition in an independent GWAS study in the same genetic background. Thus, our results indicate that the lipid metabolism of FAs is differently modulated when the FA composition in muscle differs. For instance, a high content of PUFA may reduce FA and glucose uptake resulting in an inhibition of the lipogenesis. These results are consistent with previous studies of our group analysing the liver and the adipose tissue transcriptomes providing a view of each of the main organs involved in lipid metabolism.
The results obtained in the muscle transcriptome analysis increase the knowledge of the gene regulation of IMF deposition, FA profile and meat quality, in terms of taste and nutritional value. Besides, our results may be important in terms of human health.
猪肌肉脂肪酸谱除了对人类健康有影响外，还决定肉质和口感。RNA测序技术使我们能够以前所未有的细节探索猪肌肉转录组。本研究的目的是鉴定两组6头母猪之间的差异表达基因，这两组母猪属于伊比利亚×长白回交群体，根据脂肪酸谱具有极端表型。
我们对肌肉转录组进行了测序，获得了7.875亿条75bp的双端 reads。约85.1%的 reads 被映射到参考基因组。在总 reads 中，79.1%位于外显子，6.0%位于内含子，14.9%位于基因间区域，表明参考基因组中未注释的表达区域。我们将34.5%的基因间区域鉴定为散布的重复区域。我们总共预测了2372个假定蛋白质。对131个差异表达基因的通路分析表明，统计学上最显著的代谢通路与脂质代谢有关。此外，在相同遗传背景下的一项独立全基因组关联研究中，18个差异表达基因位于与肌内脂肪组成相关的基因组区域。因此，我们的结果表明，当肌肉中的脂肪酸组成不同时，脂肪酸的脂质代谢受到不同的调节。例如，高含量的多不饱和脂肪酸可能会减少脂肪酸和葡萄糖的摄取，从而抑制脂肪生成。这些结果与我们小组之前分析肝脏和脂肪组织转录组的研究一致，提供了参与脂质代谢的每个主要器官的情况。
肌肉转录组分析获得的结果增加了我们对肌内脂肪沉积、脂肪酸谱和肉质在口感和营养价值方面的基因调控的认识。此外，我们的结果在人类健康方面可能很重要。
