Cardoso Tainã Figueiredo, Quintanilla Raquel, Tibau Joan, Gil Marta, Mármol-Sánchez Emilio, González-Rodríguez Olga, González-Prendes Rayner, Amills Marcel
Department of Animal Genetics, Center for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain.
CAPES Foundation, Ministry of Education of Brazil, Brasilia D. F., Zip Code 70.040-020, Brazil.
BMC Genomics. 2017 Aug 10;18(1):603. doi: 10.1186/s12864-017-3986-x.
The genetic basis of muscle fat deposition in pigs is not well known. So far, we have only identified a limited number of genes involved in the absorption, transport, storage and catabolism of lipids. Such information is crucial to interpret, from a biological perspective, the results of genome-wide association analyses for intramuscular fat content and composition traits. Herewith, we have investigated how the ingestion of food changes gene expression in the gluteus medius muscle of Duroc pigs.
By comparing the muscle mRNA expression of fasted pigs (T0) with that of pigs sampled 5 h (T1) and 7 h (T2) after food intake, we have detected differential expression (DE) for 148 (T0-T1), 520 (T0-T2) and 135 (T1-T2) genes (q-value <0.05 and a |FC| > of 1.5). Many of these DE genes were transcription factors, suggesting that we have detected the coordinated response of the skeletal muscle to nutrient supply. We also found DE genes with a dual role in oxidative stress and angiogenesis (THBS1, THBS2 and TXNIP), two biological processes that are probably activated in the post-prandial state. Finally, we have identified several loci playing a key role in the modulation of circadian rhythms (ARNTL, PER1, PER2, BHLHE40, NR1D1, SIK1, CIART and CRY2), a result that indicates that the porcine muscle circadian clock is modulated by nutrition.
We have shown that hundreds of genes change their expression in the porcine skeletal muscle in response to nutrient intake. Many of these loci do not have a known metabolic role, a result that suggests that our knowledge about the genetic basis of muscle energy homeostasis is still incomplete.
猪肌肉脂肪沉积的遗传基础尚不明确。到目前为止，我们仅鉴定出了有限数量的参与脂质吸收、运输、储存和分解代谢的基因。这些信息对于从生物学角度解释全基因组关联分析中肌内脂肪含量和组成性状的结果至关重要。在此，我们研究了食物摄入如何改变杜洛克猪臀中肌中的基因表达。
通过比较禁食猪（T0）与进食后5小时（T1）和7小时（T2）采样猪的肌肉mRNA表达，我们检测到148个（T0-T1）、520个（T0-T2）和135个（T1-T2）基因存在差异表达（q值<0.05且|FC|>1.5）。这些差异表达基因中有许多是转录因子，这表明我们检测到了骨骼肌对营养供应的协同反应。我们还发现了在氧化应激和血管生成中具有双重作用的差异表达基因（THBS1、THBS2和TXNIP），这两个生物学过程可能在餐后状态下被激活。最后，我们确定了几个在昼夜节律调节中起关键作用的基因座（ARNTL、PER1、PER2、BHLHE40、NR1D1、SIK1、CIART和CRY2），这一结果表明猪肌肉生物钟受营养调节。
我们已经表明，数百个基因在猪骨骼肌中会因营养摄入而改变其表达。这些基因座中有许多没有已知的代谢作用，这一结果表明我们对肌肉能量稳态遗传基础的了解仍然不完整。
