GSE64523
The miRNA Transcriptome directly Reflect the Physiological and Biochemical Differences between Red, White and Intermediate Muscle Fiber Types
MicroRNAs (miRNAs) are small non-coding RNAs that can regulate the expression of their target genes at post-transcriptional level. Skeletal muscle comprises different ?ber types that can be broadly classified as red, intermediate and white fiber types. Recently, a set of miRNAs were identified to be expressed on a fiber type-specific manner between red and white fiber types. Nonetheless, an integral explanation of the miRNA transcriptome differences in all three fiber types is long overdue. Herein, we collected 15 kinds of porcine skeletal muscles from different anatomic locations, which were then clearly divided into red, white and intermediate fiber type based on the hierarchical clustering analysis for the ratios of myosin heavy chain (MHC) isoforms. We further illustrated that three muscles, which typically represented each muscle fiber type (i.e. red: peroneal longus (PL), intermediate: psoas major muscle (PMM), white: longissimus dorsi muscle (LDM)), have distinct metabolic patterns of mitochondrial and glycolytic enzyme levels. In addition, we constructed the small RNA libraries for PL, PMM and LDM using deep sequencing approach. Results showed that, the differentially expressed miRNAs were mainly enriched in PL and played a vital role in myogenesis and energy metabolism. Overall, this comprehensive analysis will contribute to a better understanding of the miRNA regulatory mechanism for the phenotypic diversity of skeletal muscles. Overall design: 3 sample