Department of Research Livestock, Xinjiang Academy of Animal Science, Urumqi, Xinjiang 830000, China; Department of Food Science and Engineering, Gansu Agricultural University, Lanzhou, Gansu 730070, China.
Department of Food Science and Engineering, Gansu Agricultural University, Lanzhou, Gansu 730070, China.
Gene. 2020 May 30;741:144537. doi: 10.1016/j.gene.2020.144537. Epub 2020 Mar 7.
Breed improvement is an important genetic process affecting meat quality. Compared with Kazakh cattle, Xinjiang brown cattle have significantly improved carcass quality and meat quality. To elucidate the molecular mechanisms underlying the improvements in Xinjiang brown cattle and the differences in beef quality between the two breeds, we used RNA-Seq to study differentially expressed genes and miRNAs and regulatory pathways related to adipogenesis, myogenesis and fibrogenesis in the longissimus dorsi muscles of Xinjiang brown cattle and Kazakh cattle. The results showed that 1669 genes were differentially expressed in the longissimus dorsi muscle tissues of Xinjiang brown cattle and Kazakh cattle; 879 genes were upregulated and 790 genes were downregulated in Xinjiang brown cattle compared to Kazakh cattle. These genes were mainly involved in PPAR signaling, unsaturated fatty acid biosynthesis and vascular smooth muscle contraction. Additionally, 346 differentially expressed miRNAs were identified, of which 265 miRNAs were downregulated and 81 miRNAs were upregulated in Xinjiang brown cattle compared to Kazakh cattle. Association analysis of the differentially expressed genes and miRNAs revealed that 86 differentially expressed miRNAs related to adipogenesis were associated with 31 differentially expressed genes, 76 differentially expressed miRNAs associated with myogenesis were associated with 28 differentially expressed genes, and 54 differentially expressed miRNAs associated with fibrogenesis were associated with 19 differentially expressed genes. miRNA-target gene networks were also constructed. Finally, the expression levels of 19 genes and miRNAs were verified by qRT-PCR. Some differentially expressed genes, including FABP4, ACTA2 and ACTG2, were shown to play an important role in beef meat quality. This is the first study to perform transcriptomic analysis of muscle tissues from Xinjiang brown and Kazakh cattle.
品种改良是影响肉质的重要遗传过程。与哈萨克牛相比，新疆褐牛的胴体质量和肉质有显著提高。为了阐明新疆褐牛改良的分子机制以及两个品种间牛肉质量的差异，我们使用 RNA-Seq 研究了新疆褐牛和哈萨克牛背最长肌中与脂肪生成、肌肉生成和纤维生成相关的差异表达基因和 miRNA 以及调控途径。结果表明，1669 个基因在新疆褐牛和哈萨克牛的背最长肌组织中差异表达；与哈萨克牛相比，新疆褐牛中有 879 个基因上调，790 个基因下调。这些基因主要参与 PPAR 信号转导、不饱和脂肪酸生物合成和血管平滑肌收缩。此外，鉴定出 346 个差异表达的 miRNA，其中 265 个 miRNA 在新疆褐牛中下调，81 个 miRNA 上调。差异表达基因和 miRNA 的关联分析表明，与脂肪生成相关的 86 个差异表达 miRNA 与 31 个差异表达基因相关，与肌肉生成相关的 76 个差异表达 miRNA 与 28 个差异表达基因相关，与纤维生成相关的 54 个差异表达 miRNA 与 19 个差异表达基因相关。还构建了 miRNA-靶基因网络。最后，通过 qRT-PCR 验证了 19 个基因和 miRNA 的表达水平。一些差异表达基因，包括 FABP4、ACTA2 和 ACTG2，在牛肉肉质中发挥重要作用。这是首次对新疆褐牛和哈萨克牛肌肉组织进行转录组分析的研究。
