Abstract：PCR primers were designed according to the adipocyte fatty acid-binding protein gene (A-FABP) of cattle (Bos taurus). A 399 bp cDNA fragment (GenBank accession No. EU815937.1) of A-FABP gene was obtained by RT-PCR using total RNA from subcutaneous fat of adult Jiulong yak (B. grunniens). This fragment showed 98.7% nucleotide sequence similarities with cattle, with four amino acid substitutions and resulted in a shift of theoretical isoelectric point. The expression profiling of A-FABP in Jiulong yak tissues were analyzed using semi-quantitative RT-PCR. A-FABP expression was observed in fat, skeletal muscle, heart, liver, kidney and spleen tissues except for lung, respectively. The expression of A-FABP in fat tissue was significantly higher than other tissues studied (P<0.01), and also exhibited high level in liver and skeletal muscle. The expression of A-FABP gene in longissimus muscle of 0.5 and over 9 years old Jiulong yaks was markedly higher than that of the age of 3.5 and 5.5 years old (P<0.05), respecctively. Moreover, its expression showed significant correlation with intramuscular fat content of longissimus muscle.
