Differential proteome and transcriptome analysis of porcine skeletal muscle during development

To gain further insight into the molecular mechanism of porcine skeletal muscle development, we combined MS characterization of proteins with high-throughput screening of differential mRNAs obtained from purebred Meishan longissimus dorsi muscle (LM) at four stages of 65 days post conception, 3, 60 and 120 days after birth. Strikingly, the dramatic differences were observed in embryo and newborn pigs, whereas 60 and 120 days pigs exhibited similar patterns in protein and mRNA expression. At the protein level, 66 differentially expressed proteins were identified. The development-dependent alterations in protein abundance indicated dramatic changes in metabolism, myofibrillar filaments, cytoskeleton, contractile activity and stress response, and signal transduction. At the transcript level, gene expression was measured with the Affymetrix Porcine Genechip, and 338 genes, representing approximately 1.7% of the chromosome, differed by two fold or more between the neighboring growth phases. Analysis of one such comparison, the expression patterns of most differential proteins showed a positive correlation with their gene expression at the transcript level during skeletal muscle development. Overall, many proteins or genes were previously unrecognized as differentially expressed during growth stages, and they represented novel starting points for understanding the developmental characteristics of biochemical and physiological properties in porcine skeletal muscle.