Muscle transcriptome profiling in divergent phenotype swine breeds during growth using microarray and RT-PCR tools

Area of Science:

• Animal Genetics
• Molecular Biology
• Comparative Genomics

Background:

• The Casertana (CT) breed is an autochthonous Italian pig breed known for slow growth and high backfat accumulation.
• Cosmopolitan breeds like Large White (LW) and crossbreeds (CB) exhibit faster growth rates.
• Understanding genetic differences in muscle development is crucial for livestock improvement.

Purpose of the Study:

• To compare muscle tissue gene expression during growth between the CT breed and cosmopolitan pig breeds.
• To identify genes and pathways associated with differential growth rates and muscle development.
• To elucidate the genetic basis of the CT breed's unique growth characteristics.

Main Methods:

• Utilized a microarray with 10,665 70-mer oligonucleotide probes for gene expression analysis.
• Collected longissimus dorsi muscle tissues from pigs at 3, 6, 9, and 11 months of age.
• Validated findings using real-time PCR and performed time series cluster analysis.

Main Results:

• Identified 173 differentially expressed genes between CT and cosmopolitan breeds at 3 months of age.
• Time series cluster analysis revealed distinct gene expression patterns in CT pigs.
• Significant differences were observed in genes related to contractile fibers and muscle development transcription factors.

Conclusions:

• The CT breed displays a unique muscle gene expression profile during growth compared to LW and CB breeds.
• Differential gene expression is linked to variations in muscle development and differentiation rates.
• These findings provide insights into the genetic underpinnings of divergent pig growth phenotypes.