In-Depth Interpretation of Lamb-Related Protein Network Map for Muscle Formation Mechanism, Postmortem Meat Quality,...

Area of Science:

• Animal Science
• Meat Science
• Proteomics

Background:

• Skeletal muscle fiber type significantly influences lamb meat quality traits.
• Key proteins and regulatory mechanisms affecting lamb muscle fiber development and meat characteristics remain unclear.

Purpose of the Study:

• To investigate differences in skeletal muscle fiber types and protein expression between Longissimus thoracis (LT) and Biceps Femoris (BF) muscles in lambs.
• To identify key proteins and regulatory pathways influencing lamb muscle fiber characteristics and meat quality traits.

Main Methods:

• Comparative analysis of LT and BF muscles from crossbred ewe lambs.
• Assessment of myofiber proportions and MyHC IIa gene expression.
• Tandem mass tags (TMT)-based proteomic analysis to identify differentially abundant proteins.
• Functional annotation and enrichment analysis of identified proteins.

Main Results:

• BF muscle exhibited a higher proportion of oxidative myofibers and MyHC IIa gene expression compared to LT muscle.
• BF muscle showed improved meat quality: lower shear force, lower b* value, lower crude fat, higher pH24h, and higher moisture.
• Proteomic analysis identified 285 differentially abundant proteins linked to muscle structure, glycolysis, and Ca2+ regulation.

Conclusions:

• Proteins involved in glycolysis, carbohydrate metabolism, and fiber type transition are significantly enriched in BF muscle.
• These identified proteins and pathways likely contribute to the observed differences in muscle fiber characteristics and meat quality between LT and BF muscles.
• Findings provide novel insights for enhancing meat attributes in the lamb industry through targeted muscle development strategies.