Abstract: Annealing control primer (ACP) system was applied to find candidate genes related to lipidosis in muscle of Yanbian yellow cattle by screening differentially expressed genes (DEGs) in Longissimus dorsi, which had significant dif-ference on intramuscular fat (IMF) content. Thirty steers, aged at 28 month-bullocks were selected to measure the IMF content in L. dorsi. Two groups of bullocks (three heads per group) with the highest and the lowest contents of IMF were selected to build a RNA pool, and DEGs of two groups were analyzed by ACP system. Twelve DEGs were identified and sequenced by amplification with 20 arbitrary primers (fragment sizes were 200–890 bp). In these genes, eight were already known as functional groups of cytoskeleton, cytokine signal transduction, protein synthesis, energy metabolismand, and others, four were unknown. All the 12 ESTs were screened by ACP system, which may participated in regulating on lipidosis in muscle. This study established a foundation for further screening of lipidosis related genes.

Key words: differential expression genes(DEGs), Yanbian yellow cattle, Longissimus dorsi, intramuscular fat, annealing control primer (ACP) system