Comparing the mRNA expression profile of psoas major and longissimus dorsi muscles in pig

To explore the differentially expressed mRNAs between oxidative and glycolytic muscles, Qianbei black pigs were slaughtered and longissimus dorsi muscle (LDM) and psoas major muscle (PMM) were selected and sequenced using Illumina Hiseq TM 4000. Bioinformatics analysis and differentially expressed genes were analyzed by GO and KEGG. qRT-PCR was used to validate the RNAseq result. As a result, 69 differentially expressed genes were identified, with 46 down regulated genes and 23 up regulated genes in LDM versus PMM, which were categorized into 44 functional groups under three GO classifications. KEGG pathway analysis revealed 20 pathways were enriched. qRT-PCR shows the expression trends of ND6, MYH7, TBX1, FOS and SLC7A5 are consist with the RNA-seq result. We speculated these five genes may involve in differentiation of muscle cells, metabolism of carbohydrate and lipid, deposits of intramuscular fat and transformation of different types of muscle fibers.