Comparative analysis on gene expression profiles in cattle subcutaneous fat tissues.

Fat related carcass traits are important to the beef industry due to their association with value of the meat. In this study, we attempted to discover the genes that are associated with fat metabolism by identification of differentially expressed genes in subcutaneous adipose tissues of beef steers with different backfat thicknesses. Microarray analysis was performed using a bovine specific oligo-platform containing 8329 probes. In total, 360 differentially expressed genes were identified and their functions were characterized by bioinformatical tools to elucidate molecular pathways. 45 out of 360 differentially expressed genes were found to be involved in 82 KEGG pathways. Validation of 6 selected differentially expressed genes by quantitative real-time PCR revealed correlations between backfat thickness and their expression levels. Our results suggest that expression differences of novel genes and the genes that have been known as genetic markers for fat related traits may be associated with backfat development in beef cattle. Moreover, the gene expression differences were also compared between two cattle crossbreds. The observed different association between the expression of selected genes and breed types suggested that the mechanisms of fat metabolism may differ in response to genotypes. 2008 Elsevier Inc. All rights reserved.