Identification of genes in longissimus dorsi muscle differentially expressed between Wannanhua and Yorkshire pigs using RNA-sequencing.

Western commercial pig breeds have been intensively selected, resulting in a sizeable, rapid and efficient accretion of muscle but a reduction in meat quality. When compared with Western commercial pig breeds, Chinese indigenous pig breeds exhibited slower growth rates and reduced lean meat content but superior perceived meat quality. To study the factors that determine meat quality, we examined piglets of one Western commercial breed (Yorkshire) and one Chinese indigenous breed (Wannanhua) and sequenced the longissimus dorsi muscle using RNA-sequencing (RNA-seq). We analyzed their transcriptomes, focusing on identifying candidate genes that may influence porcine muscle growth, meat quality and adipose deposition. Gene Ontology functional enrichment and pathway enrichment analyses identified differentially expressed genes (DEGs) primarily associated with glycolytic metabolism, biological processes of muscle development and signaling pathways related to fatty acid metabolism, growth and carcass traits. This finding suggests that the DEGs may play important roles in determining meat quality traits. Quantitative real-time reverse transcription polymerase chain reaction confirmed the differential expression of 12 selected DEG. This study identified a number of novel candidate genes for porcine meat quality and carcass traits that merit further investigation to elucidate the molecular mechanisms responsible for muscle growth and fat deposition.