Circular RNA transcriptome across multiple tissues reveal skeletal muscle-specific circPSME4 regulating myogenesis

Area of Science:

• Animal Genetics
• Molecular Biology
• Genomics

Background:

• Significant phenotypic differences exist between Western commercial pigs and Chinese local breeds in traits like meat production and growth rate.
• Comparative transcriptomics has identified candidate genes, but the role of circular RNAs (circRNAs) in pig tissue development remains largely unexplored.

Purpose of the Study:

• To conduct a comprehensive genome-wide analysis of circRNA expression profiles across ten tissues in Luchuan (Chinese local breed) and Duroc (Western commercial breed) pigs.
• To identify differentially expressed and tissue-specific circRNAs and investigate the function of a novel circRNA in skeletal muscle development.

Main Methods:

• Genome-wide circRNA expression profiling across ten tissues from Luchuan and Duroc pigs.
• Identification and annotation of circRNAs, differential expression analysis, and enrichment analysis.
• Competitive endogenous RNA (ceRNA) network construction and functional analysis of circPSME4 in myoblasts.

Main Results:

• A total of 56,254 circRNAs were identified, with 42.9% being novel and 33.7% showing differential expression between the breeds.
• 538 tissue-specific circRNAs were identified, predominantly in brain and skeletal muscle tissues.
• Skeletal muscle-specific circPSME4 was found to regulate myoblast proliferation and differentiation, acting as a novel regulator of skeletal muscle development.

Conclusions:

• This study provides a valuable resource of circRNAs for pig breeding and biomedical research.
• Differentially expressed circRNAs likely contribute to the phenotypic divergence between Chinese local and Western commercial pigs.
• circPSME4 is identified as a novel regulator of skeletal muscle development, with potential applications in improving meat production traits.