Integrative transcriptomic, proteomic and metabolomic analyses yields insights into muscle fiber type in cattle.

Muscle fiber is an important factor in beef quality. Here, we compared fast-type longissimus dorsi muscle and slow-type psoas major muscle from cattle using transcriptomic, proteomic and metabolomic analyses. A total of 1717 differentially expressed genes (DEGs), 297 differentially abundant proteins (DAPs) and 193 differentially abundant metabolites (DAMs) were identified between LD and PM tissue, respectively. For verification, we selected 10 DEGs for qRT-PCR and 6 DAPs for western blotting, and showed they were consistent between the two approaches. GO and KEGG enrichment analyses revealed that some DEGs, DAPs and DAMs were enriched in muscle fiber type-associated GO terms and pathways. Many of them are involved in glycolysis, TCA and fatty acid metabolism. Integrated multi-omics analysis showed a correlation coefficient of 0.6244 between the transcriptome and proteome. This study provides a new understanding of molecular mechanisms involved in the determination of bovine muscle fiber type and meat quality.