Li Chenchen, Wang Yinuo, Sun Xiaohui, Yang Jinjin, Ren Yingchun, Jia Jinrui, Yang Gongshe, Liao Mingzhi, Jin Jianjun, Shi Xin'e
Laboratory of Animal Fat Deposition and Muscle Development, Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Center of Bioinformatics, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China.
BMC Genomics. 2024 Apr 24;25(1):400. doi: 10.1186/s12864-024-10271-9.
Skeletal muscle is composed of muscle fibers with different physiological characteristics, which plays an important role in regulating skeletal muscle metabolism, movement and body homeostasis. The type of skeletal muscle fiber directly affects meat quality. However, the transcriptome and gene interactions between different types of muscle fibers are not well understood.
In this paper, we selected 180-days-old Large White pigs and found that longissimus dorsi (LD) muscle was dominated by fast-fermenting myofibrils and soleus (SOL) muscle was dominated by slow-oxidizing myofibrils by frozen sections and related mRNA and protein assays. Here, we selected LD muscle and SOL muscle for transcriptomic sequencing, and identified 312 differentially expressed mRNA (DEmRs), 30 differentially expressed miRNA (DEmiRs), 183 differentially expressed lncRNA (DElRs), and 3417 differentially expressed circRNA (DEcRs). The ceRNA network included ssc-miR-378, ssc-miR-378b-3p, ssc-miR-24-3p, XR_308817, XR_308823, SMIM8, MAVS and FOS as multiple core nodes that play important roles in muscle development. Moreover, we found that different members of the miR-10 family expressed differently in oxidized and glycolytic muscle fibers, among which miR-10a-5p was highly expressed in glycolytic muscle fibers (LD) and could target MYBPH gene mRNA. Therefore, we speculate that miR-10a-5p may be involved in the transformation of muscle fiber types by targeting the MYHBP gene. In addition, PPI analysis of differentially expressed mRNA genes showed that ACTC1, ACTG2 and ACTN2 gene had the highest node degree, suggesting that this gene may play a key role in the regulatory network of muscle fiber type determination.
We can conclude that these genes play a key role in regulating muscle fiber type transformation. Our study provides transcriptomic profiles and ceRNA interaction networks for different muscle fiber types in pigs, providing reference for the transformation of pig muscle fiber types and the improvement of meat quality.
骨骼肌由具有不同生理特性的肌纤维组成，在调节骨骼肌代谢、运动和身体内环境稳态中发挥重要作用。骨骼肌纤维类型直接影响肉质。然而，不同类型肌纤维之间的转录组和基因相互作用尚不清楚。
本文选取180日龄大白猪，通过冰冻切片及相关mRNA和蛋白质检测发现，背最长肌（LD）以快速酵解型肌原纤维为主，比目鱼肌（SOL）以慢氧化型肌原纤维为主。在此，我们选取LD肌和SOL肌进行转录组测序，鉴定出312个差异表达mRNA（DEmRs）、30个差异表达miRNA（DEmiRs）、183个差异表达lncRNA（DElRs）和3417个差异表达circRNA（DEcRs）。ceRNA网络包括ssc-miR-378、ssc-miR-378b-3p、ssc-miR-24-3p、XR_308817、XR_308823、SMIM8、MAVS和FOS等多个核心节点，它们在肌肉发育中起重要作用。此外，我们发现miR-10家族的不同成员在氧化型和糖酵解型肌纤维中表达不同，其中miR-10a-5p在糖酵解型肌纤维（LD）中高表达，且可靶向MYBPH基因mRNA。因此，我们推测miR-10a-5p可能通过靶向MYHBP基因参与肌纤维类型的转变。此外，对差异表达mRNA基因的PPI分析表明，ACTC1、ACTG2和ACTN2基因的节点度最高，表明该基因可能在肌纤维类型决定调控网络中起关键作用。
我们可以得出结论，这些基因在调节肌纤维类型转变中起关键作用。我们的研究提供了猪不同肌纤维类型的转录组图谱和ceRNA相互作用网络，为猪肌纤维类型转变和肉质改善提供参考。
