Multi-Omics Insights into Postnatal Skeletal Muscle Development in Duroc Pigs

Area of Science:

• Animal Science
• Molecular Biology
• Genomics

Background:

• Skeletal muscles constitute 40% of mammalian body mass and display significant anatomical heterogeneity.
• Current animal husbandry practices overemphasize the longissimus dorsi muscle, neglecting others.
• Understanding muscle-specific development is crucial for optimizing livestock production.

Purpose of the Study:

• To investigate the molecular basis of skeletal muscle heterogeneity in Duroc pigs.
• To identify key genes and metabolites regulating muscle development and fiber-type transformation.
• To provide insights for genetic improvement strategies in meat-producing animals.

Main Methods:

• Integrated bulk RNA sequencing (bulk RNA-seq) and Liquid Chromatography-Mass Spectrometry (LC-MS) analyses.
• Examined Soleus (SOL), Gastrocnemius (GAS), and Psoas major muscles (PMM) at three developmental stages.
• Analyzed gene expression (e.g., MYH7, MYH1, MYH4) and metabolite profiles.

Main Results:

• Identified nine critical genes and eight metabolites involved in muscle development and fiber-type switching.
• Observed increasing heterogeneity between SOL and GAS muscles during development, with PMM showing higher initial heterogeneity.
• Detected stage-specific and muscle-specific expression patterns for myosin heavy chain genes (MYH7, MYH1, MYH4).
• Found a developmental shift in signaling pathways, from MAPK to actin cytoskeleton regulation.

Conclusions:

• Muscle heterogeneity is a significant factor in skeletal muscle development and impacts meat production.
• The study identified key molecular players and pathways (e.g., MAPK, actin cytoskeleton) driving muscle development and fiber-type switching.
• Integrated multi-omics data offers novel molecular breeding strategies for enhancing meat-producing animal genetics.