Exploring Multi-Tissue Alternative Splicing and Skeletal Muscle Metabolism Regulation in Obese- and Lean-Type Pigs

Area of Science:

• Genomics and Molecular Biology
• Transcriptomics and Post-Transcriptional Regulation

Background:

• Alternative splicing (AS) is a key post-transcriptional regulatory mechanism.
• AS generates transcriptome and proteome diversity, influencing biological functions.
• Understanding AS differences is crucial for livestock breeding and physiology.

Purpose of the Study:

• To comprehensively profile alternative splicing events in Duroc (lean) and Luchuan (obese) pigs.
• To identify genes with differential AS related to phenotypic differences.
• To explore the functional implications of AS in different pig tissues.

Main Methods:

• Comprehensive AS profiling across nine tissues from two pig breeds.
• Identification and quantification of AS events, categorizing by type (e.g., skipped exon).
• Functional enrichment analysis and overlap analysis with differentially expressed genes (DEGs).

Main Results:

• Identified 94,990 AS events across 14,393 genes.
• Skipped exon (SE) events constituted 80% of all identified AS events.
• Genes with extensive AS (>10 events) were linked to tissue-specific functions.
• Highest overlap between differentially alternative splicing genes (DSGs) and DEGs found in heart and skeletal muscle.
• Validated three key genes (PYGM, MAPK11, CAMK2B) in the glucagon signaling pathway with significant AS differences between breeds.

Conclusions:

• Provides novel insights into AS regulation and its role in tissue physiology.
• Highlights AS as a molecular basis for phenotypic differences between lean and obese pigs.
• Identified AS signatures valuable for improving pig breeding strategies.