Cloning, Molecular Characteristics and Tissue Expression Analysis of SREBF1 Gene in Binglangjiang Buffalo

Purpose To elucidate the molecular characteristics and tissue expression specificity of buffalo sterol regulatory element binding transcription factor 1 (SREBF1), revealing the molecular function preliminarily.

Methods The Binglangjiang buffalo was used as research object, and the complete coding sequence (CDS) of buffalo SREBF1 gene was cloned by RT-PCR. The molecular characteristics of SREBF1 were analyzed by bioinformatics method. The expression specificity of SREBF1 gene in multiple tissues of lactating buffalo was further detected by qPCR.

Results The CDS length of buffalo SREBF1 gene was 3 438 bp, it encoded a protein composed of 1 145 amino acids. The protein was hydrophilic and contained a bHLHzip_SREBP1 (AA319-393) domain, and without transmembrane structure and signal peptide. The SREBF1 protein was localized in the nucleus and endoplasmic reticulum. The main functions were to bind and regulate DNA transcription, and participate in lipid metabolism. The primary structure, physicochemical characteristics, the composition of domains, and advanced structure of SREBF1 protein were highly similar among buffalo and other Bovidae species. Phylogenetic analysis of amino acid sequence based on SREBF1 showed buffalo clustered with other Bovidae species. The expression in eight tissues of lactating buffaloes showed that SREBF1 gene expression was higher in mammary gland, followed by liver, skeletal muscle, pituitary gland and kidney, and lower in spleen, rumen and heart.

Conclusion The amino acid sequence of SREBF1 in buffalo and other Bovidae species is highly similar. Buffalo SREBF1 can regulate DNA transcription and play a role in tissues with high lipid metabolism.