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Intramuscular fat deposition and the fatty acid profiles of beef are determined mainly by lipid metabolism, which dictates the balance between fat deposition and fat removal in skeletal muscle.Oleic acid(C18∶1n9), primarily responsible for soft fat, is a major monouasaturated fatty acid, which accounts for about33% of the fatty acid in beef, and is considered to have the least negative effect on serum cholesterol concentration.Fatty acid transport protein 1 (FATP1), an integral membrane protein that facilitates long-chain fatty acids (LCFA) influx, is involved in the genetic network for oleic acid synths in beef and its expression exhibited significant positive correlations with Intramuscular fat (IMF) content in the longissimus thoracis.However, the expression mechanism of FATP1 was still unclear.In this study, we determined that bovine FATP1was highly expressed in subcutaneous adipose tissue and longissimus thoracis.To elucidate the molecular mechanisms involved in bovine FATP1 regulation, we cloned and characterized the promoter region of FATP1.Applying 5'-rapid amplification of cDNA end analysis, we identified two alternative splice variants present in longissimus thoracis.Using a series of 5' deletion promoter plasmids in luciferase reporter assays, we found that108 base pairs upstream from the transcription initiation site (TSSs) was its core promoter.Electrophoretic mobility shift assay combined with site-directed mutation experiment indicated that KLF15 was important transcription factors for bovine FATP1.These results might provide further information on regulatory roles of FATP1 gene in mediating the lipid composition of beef.