Gansu Key Laboratory of Herbivorous Animal Biotechnology, College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, China.
Int J Mol Sci. 2024 Sep 21;25(18):10151. doi: 10.3390/ijms251810151.
As a class of regulatory factors, microRNAs (miRNAs) play an important role in regulating normal muscle development and fat deposition. Muscle and adipose tissues, as major components of the animal organism, are also economically important traits in livestock production. However, the effect of miRNA expression profiles on the development of muscle and adipose tissues in yak is currently unknown. In this study, we performed RNA sequencing (RNA-Seq) on Tianzhu white yak longissimus dorsi muscle tissue obtained from calves (6 months of age, M6, = 6) and young (30 months of age, M30, = 6) and adult yak (54 months of age, M54, = 6) to identify which miRNAs are differentially expressed and to investigate their temporal expression profiles, establishing a regulatory network of miRNAs associated with the development of muscle and adipose. The results showed that 1191 miRNAs and 22061 mRNAs were screened across the three stages, of which the numbers of differentially expressed miRNAs (DE miRNAs) and differentially expressed mRNAs (DE mRNAs) were 225 and 450, respectively. The expression levels of the nine DE miRNAs were confirmed using a reverse transcription quantitative PCR (RT-qPCR) assay, and the trend of the assay results was generally consistent with the trend of the transcriptome profiles. Based on the expression trend, DE miRNAs were categorized into eight different expression patterns. Regarding the expression of DE miRNAs in sub-trends Profile 1 and Profile 2 ( < 0.05), the gene expression patterns were upregulated (87 DE miRNAs). Gene ontology (GO) and Kyoto Encyclopedia of Genes Genomes (KEGG) analyses showed that the identified DE miRNAs and DE mRNAs were enriched in pathway entries associated with muscle and intramuscular fat (IMF) growth and development. On this basis, we constructed a DE miRNA-mRNA interaction network. We found that some DE mRNAs of interest overlapped with miRNA target genes, such as , , , , , (muscle development), , , , , , and (intramuscular fat deposition). These results provide a valuable resource for further studies on the molecular mechanisms of muscle tissue development in yak and also lay a foundation for investigating the interactions between genes and miRNAs.
作为一类调控因子，微小 RNA（miRNA）在调节正常肌肉发育和脂肪沉积方面发挥着重要作用。肌肉和脂肪组织作为动物机体的主要组成部分，也是畜牧业生产中具有重要经济意义的性状。然而，miRNA 表达谱对牦牛肌肉和脂肪组织发育的影响目前尚不清楚。本研究通过对天祝白牦牛幼龄（6 月龄，M6，n=6）、青年（30 月龄，M30，n=6）和成年（54 月龄，M54，n=6）牛背最长肌组织进行 RNA 测序（RNA-Seq），鉴定出差异表达的 miRNA，并对其进行了时空表达谱分析，构建了与肌肉和脂肪发育相关的 miRNA 调控网络。结果表明，在这三个阶段共筛选出 1191 个 miRNA 和 22061 个 mRNA，其中差异表达 miRNA（DE miRNA）和差异表达 mRNA（DE mRNA）的数量分别为 225 个和 450 个。使用逆转录定量 PCR（RT-qPCR）实验验证了 9 个 DE miRNA 的表达水平，实验结果与转录组图谱的趋势基本一致。根据表达趋势，DE miRNA 分为 8 种不同的表达模式。在 Profile 1 和 Profile 2（<0.05）中，DE miRNA 的表达呈上调趋势（87 个 DE miRNA）。GO 和 KEGG 分析表明，所鉴定的 DE miRNA 和 DE mRNA 在与肌肉和肌内脂肪（IMF）生长和发育相关的途径中富集。在此基础上，构建了 DE miRNA-mRNA 互作网络。发现一些感兴趣的 DE mRNA 与 miRNA 靶基因重叠，如、、、、、（肌肉发育）、、、、、（肌内脂肪沉积）。这些结果为进一步研究牦牛肌肉组织发育的分子机制提供了有价值的资源，也为研究基因与 miRNA 之间的相互作用奠定了基础。
