Characterization of the polycystic kidney disease 2 gene promoter

• Key regulatory elements for human and porcine PKD2 gene remain unknown.
• G4 and Sp1 binding sites are abundantly distributed in the core promoter region of porcine PKD2 gene.
• G4 motif and Sp1 are critical regulators for mediating the transcription of PKD2 in human and swine.
• Highly conserved regulatory regions and transcriptional pattern between human and porcine PKD2.

The key regulatory elements for PKD2 transcription remain unclear. To identify these core elements, we characterized porcine PKD2 promoter with bioinformatics and molecular tools and found porcine PKD2 promoter bearing typical features of enriched CpG and less TATA. Further studies demonstrated that the core region was located in fragment − 483 to + 100. Subsequent biophysical binding assays and mutation experiments revealed that G4 motif and Sp1 are critical regulators for mediating the transcription of porcine PKD2. Moreover, the same regulatory pattern was reproduced in human PKD2 promoter region, indicating the critical role of G4 and Sp1 in regulating PKD2.