Tissue expression analysis, cloning, and characterization of the 5 '-regulatory region of the bovine fatty acid binding protein 4 gene

摘要

Fatty acid binding protein 4 (FABP4) is a member of the FABP family of proteins that bind fatty acids and play important roles in fatty acid uptake and intracellular transport. In the present study, we cloned the 5'-regulatory region of bovine FABP4 and identified its transcription initiation sites. Sequence comparative analysis demonstrated amino acids and promoter sequences of FABP4 were highly conservative in mammals. Real-time PCR analysis revealed the products of bovine FABP4 were very highly expressed in subcutaneous adipose tissue. Serial deletion constructs of the bovine FABP4 5'-regulatory region evaluated in a dual-luciferase reporter assay showed that 209 bp upstream from the transcription initiation site was its core promoter. An electrophoretic mobility shift assay combined with a site-directed mutation experiment indicated that peroxisome proliferator activated receptor gamma (PPAR.), CCAAT/enhancer-binding protein beta (C/EBP beta), and sterol regulatory element-binding protein (SREBP) were important transcription factors for bovine FABP4. These results provide an important basis for further understanding the regulation of bovine FABP4.