Temporal and spatial expression of Smads and their correlation with YAP1 expression in sheep

Area of Science:

• Animal Science
• Molecular Biology
• Muscle Physiology

Background:

• Skeletal muscle development is regulated by complex signaling pathways.
• Smad proteins and Yes-associated protein 1 (YAP1) are key regulators in cellular processes, including muscle growth.
• Understanding their temporal and spatial expression patterns is crucial for elucidating muscle development mechanisms.

Purpose of the Study:

• To investigate the temporal and spatial expression patterns of Smad proteins and YAP1 in sheep skeletal muscle.
• To analyze the correlations between Smad and YAP1 expression at different growth stages and in different muscles.
• To explore the potential role of YAP1 in sheep muscle growth.

Main Methods:

• Quantitative analysis of Smad and YAP1 gene expression in gastrocnemius and extensor digitorum longus muscles of Hu sheep.
• Expression levels were assessed at three distinct growth stages: 2 days old, 2 months old, and 6 months old.
• Statistical analysis was performed to determine significant differences and correlations between gene expressions, muscle types, sexes, and age groups.

Main Results:

• Smad proteins exhibited differential expression between gastrocnemius and extensor digitorum longus muscles, with higher levels in gastrocnemius.
• Smad2, Smad3, and Smad4 expression peaked at the 2-day-old stage, while Smad7 levels varied across growth stages.
• Positive correlations were observed between YAP1 and Smad2/Smad4/Smad7, and YAP1 and MSTN expression, suggesting YAP1's involvement in muscle growth.

Conclusions:

• Smad and YAP1 expression patterns are dynamic and muscle-specific during sheep skeletal muscle development.
• YAP1 signaling is interconnected with Smad pathways and Myostatin (MSTN), indicating a role in regulating muscle mass.
• These findings provide insights into the molecular mechanisms governing sheep muscle growth and development.