PDF(Pubmed)
Abstract：
Studies have demonstrated that chronic heat stress can accelerate glycolysis, decrease glycogen content in muscle, and affect muscle quality. However, the consequences of chronic heat stress on glycogen synthesis, miRNA expression in pectoralis major (PM) muscle, and its regulatory functions remain unknown. In this study, high-throughput sequencing and cell experiments were used to explore the effects of chronic heat stress on miRNA expression profiles and the regulatory mechanisms of miRNAs in glycogen synthesis under chronic heat stress. In total, 144 cocks were allocated into 3 groups: the normal control (NC) group, the heat stress (HS) group, and the pair-fed (PF) group. In total, 30 differently expressed (DE) miRNAs were screened after excluding the effect of feed intake, which were mainly related to metabolism, signal transduction, cell growth and death. Furthermore, the gga-miR-212-5p/GYS1 axis was predicted to participate in glycogen synthesis through the miRNA-mRNA analysis, and a dual-luciferase reporter test assay confirmed the target relationship. Mechanistically, chronic heat stress up-regulated gga-miR-212-5p, which could inhibit the expression of GYS1 in the PM muscle. Knocking down gga-miR-212-5p alleviates the reduction of glycogen content caused by chronic heat stress; overexpression of gga-miR-212-5p can reduce glycogen content. This study provided another important mechanism for the decreased glycogen contents within the PM muscle of broilers under heat stress, which might contribute to impaired meat quality.
摘要：
研究表明，慢性热应激可以加速糖酵解，减少肌肉中的糖原含量，影响肌肉质量。然而,慢性热应激对糖原合成的影响，胸大肌（PM）中的miRNA表达，其调节功能仍然未知。在这项研究中,通过高通量测序和细胞实验研究慢性热应激对miRNA表达谱的影响以及miRNA在慢性热应激下糖原合成中的调控机制。总的来说,144只公鸡被分为3组：正常对照（NC）组，热应激（HS）组，和成对喂养(PF)组。总的来说,在排除采食量的影响后，筛选了30种不同表达(DE)的miRNA，主要与新陈代谢有关，信号转导，细胞生长和死亡此外，通过miRNA-mRNA分析预测gga-miR-212-5p/GYS1轴参与糖原合成，和双荧光素酶报告测试测定证实了目标关系。机械上,慢性热应激上调gga-miR-212-5p，抑制PM肌GYS1的表达。敲低gga-miR-212-5p可缓解慢性热应激引起的糖原含量降低;gga-miR-212-5p的过表达可降低糖原含量。本研究为热应激下肉鸡PM肌肉内糖原含量降低提供了另一个重要机制。这可能会导致肉质受损。
