Transcriptome analysis of subcutaneous adipose tissues in beef cattle using 3' digital gene expression-tag profiling

Area of Science:

• Animal Genomics
• Molecular Biology
• Quantitative Genetics

Background:

• Understanding the molecular basis of fat deposition in cattle is crucial for livestock improvement.
• Previous research on bovine adipose tissue gene regulation is limited.
• Genetic background significantly influences fat deposition traits.

Purpose of the Study:

• To identify genes and gene networks regulating fat deposition in bovine backfat tissue.
• To compare transcriptional profiles between two distinct cattle crossbreds (Hereford × Aberdeen Angus and Charolais × Red Angus).
• To investigate gene expression differences related to high versus low backfat thickness within breeds.

Main Methods:

• Digital gene expression-tag profiling (RNA sequencing) was performed on backfat tissues.
• Transcriptional profiles were analyzed from Hereford × Aberdeen Angus (HEAN) and Charolais × Red Angus (CHRA) steers.
• Statistical analyses identified differentially expressed genes (DEGs) between crossbreds and between high/low backfat thickness groups.

Main Results:

• A total of 18,034 genes were identified, with 650 DEGs found between the two crossbreds.
• CHRA tissues showed higher expression of development-related genes, while HEAN tissues had more metabolism and immune response genes.
• Specific DEGs related to cell proliferation, development, and lipid metabolism were identified in high backfat groups, including obesity-associated genes like PTX3 and SERPINE1 in CHRA.

Conclusions:

• Gene expression patterns in bovine backfat are significantly influenced by the cattle's genetic background.
• Distinct gene networks regulate fat deposition in different cattle breeds.
• The study provides insights into the genetic architecture of fatness traits in cattle, relevant for breeding programs.