Abstract:

This experiment was conducted to study the potential regulatory sequences of growth differentiate factor 5（GDF5）. The 5′ flanking region of bovine GDF5 gene was amplified through comparing human GDF5 gene, and then a 2 043 bp promoter sequence was confirmed after product purification, ligation, transformation and sequence. In addition, considering the confirmed human GDF5 promoter structure and the analytic result of promoter online software, the promoter sequence was analyzed. It was found that there are no CpG island existing in 5′ flanking region of bovine GDF5 gene using CpG Island Searcher program, and comparing with the human GDF5 5′ flanking sequence, about 78% nucleotide identity was showed. Meanwhile, the result showed that no typical TATA or CAAT boxes were found in bovine GDF5 promoter, and the transcription start site was mapped to -359 bp of translation start site, and the potential transcription factor binding motifs were predicted, including AMLla, Ap1, AmLla, CdxA, CdxA, TATA, AmLla, GTATA1, MZF1, CdxA, Nkx2, CdxA, S8 and SRY, in which only Ap1, AmLla, Nkx2, S8 and SRY were located at the identical positions in human and bovine, both of which were conserved. Moreover, it also showed that around the promoter region from －457 to －423 bp the repeat of GT could increase the promoter activity and a minimal enhancer element reside from －458 to －377 bp in bovine GDF5 promoter. In this experiment, we inferred the transcription start site, transcription factor binding motifs, activity sequence and minimal enhancer element in bovine GDF5 promoter, which may be helpful for exploring the mechanism of gene expression in chondrocyterestrictive.