Abstract: 【Objective】To clone the full length cDNA of heart fatty acid-binding protein (H-FABP) gene in Lanzhou fat-tailed sheep for providing a theoretical basis to study its biological function and application in sheep. 【Method】 The 5′- and 3′- gene specific primers were designed according to the alignment of known cDNA sequences of H-FABP from mammals. Technique of rapid amplification of cDNA ends (RACE) was employed to clone the full length cDNA of H-FABP gene in Lanzhou fat-tailed sheep. 【Results】 About 425 bp 5′-RACE cDNA and 231 bp 3′-RACE cDNA was obtained by 5′-RACE and 3′-RACE, respectively, using skeletal muscle RNA transcribed cDNA as template. Nest PCR was performed to clone 177 bp intermediate fragment. The full length cDNA of 748 bp H-FABP gene was spliced (GenBank Accession Number JQ780322). The open reading frame of sheep H-FABP gene is 402 bp in length, encoding a mature protein H-FABP of 133 amino acids and a resulting Mr=14 761. Phylogenetic analysis showed that H-FABP gene in Lanzhou fat-tailed sheep is more close to goat, Capra hircus. Alignment comparison indicated that nucleotide homology of H-FABP gene in sheep is more similar with mammals. However, the base transition from T to G in sixty-six of nucleotide sequence leading to the change from asparagines (N) to lysine (K) in twenty-second of amino acid sequence, which is different from other species. It is predicted that tertiary structure of H-FABP protein is very similar to H-FABP of C. hircus, having 2 α-helix, 10 antiparallel β-pleated sheets that form barrel. 【Conclusion】The full length cDNA of 748 bp H-FABP gene was first to be cloned by RACE. This finding may provide basic data for further studying the role of H-FABP gene in sheep.

Key words: Lanzhou fat-tailed sheep , H-FABP gene , rapid amplification of cDNA ends (RACE) , sequence analysis