Abstract:To investigate the transcriptional regulation of pig melanocortortin-4 receptor(MC4R) gene, 5' promoter fragment (spanned from -1 264 bp to -31 bp) was amplified with PCR method and the potential transcriptional start sites were predicted with bioinformatics method; Eleven promoter segments with different length were obtained by promoter deletion analysis and cloned into PGL3-Basic vector; then the promoter activities were determined in transiently transfected pig PK15 cell by the dual-luciferase assay system. The results indicated that there was a potential transcription start site in the region from intiation codon to -682 bp. Further analysis demonstrated that the region from -514 bp to -486 bp was important for the basic transcriptional activity and bioinformatics analysis showed that there was a cis-acting element possessing a functional binding site(HSF). HSF maybe play an important role in the regulation of MC4R gene expression.