Transcriptome profiling of mRNAs in muscle tissue of Pinan cattle and Nanyang cattle

Mammalian muscle development is regulated by complex gene networks at the molecular level. The revelation of gene regulatory mechanisms is an important basis for the study of muscle development and molecular breeding. To analyze the excellent meat performance of Pinan cattle at the molecular level, we performed high-throughput RNA sequencing to analyze the key regulatory genes that determine the muscle quality traits in Pinan cattle (n = 3) and Nanyang cattle (n = 3). We identified 57 differentially expressed genes in muscle tissue of Pinan cattle compared to that of Nanyang cattle, including 32 upregulated and 25 downregulated genes. GO enrichment analysis showed that these genes were significantly enriched in 'molecular function', including voltage-gated ion channel activity, calcium channel activity and calcium ion binding, and KEGG pathway analysis results revealed that adrenergic signaling in cardio myocytes, cell adhesion molecules and inositol phosphate metabolism pathway were significantly enriched. We identified the reliability of RNA-Seq data through RT-qPCR. Meanwhile, we found that GSTA3, PLCB1 and ISYNA1 genes are highly expressed in muscle tissue of Pinan cattle, and these genes play important roles in PI3K/Akt, MEK1/2-ERK and p53-ISYNA1 signaling pathway. In summary, our results suggested that these differentially expressed genes may play important roles in muscle development in Pinan cattle. However, the functions and mechanism of these significantly differential expressed genes should be investigated in future studies.