Identification of differentially expressed proteins in adipose tissue of divergently selected broilers.

Reducing fat has been a major goal for the broiler industry. To gain insight into the molecular mechanisms underlying the regulation of fat deposition in chickens, a 2-dimensional electrophoresis-based proteomic approach was used to analyze the differentially expressed proteins in abdominal adipose tissues of Northeast Agricultural University broiler lines divergently selected for abdominal fat content (NEAUHLF). A total of 20 differentially expressed protein spots were found in abdominal adipose tissue between fat and lean broilers at 7 wk of age. Among them, 12 protein spots were upregulated and 8 protein spots were downregulated in fat birds compared with those in lean birds. These 20 protein spots were then identified by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry and matched to 15 proteins by searching against the NCBInr and SWISS-PROT databases, including adipocyte fatty acid-binding protein, apolipoprotein A-I, long-chain acyl-coenzyme A dehydrogenase, heat shock protein beta 1, glutathione S-transferase theta 1, glutathione S-transferase class alpha, guanine nucleotide-binding protein beta polypeptide 1, syntaxin 2, vimentin, cofilin 2, otokeratin, telomerase catalytic subunit, and 3 hypothetical proteins. These proteins are mainly related to lipid metabolism, chaperone, redox, signal transduction, transport, and cytoskeleton. The results, from the point of view of protein expression, establish the groundwork for further studies of the basic genetic control of growth and development of broiler adipose tissue.