Study On Promoter Sequence With Function For Transcription Initiation Of BMPR-2 Gene

Background: BMPR-2 gene is a member of the TGF-b superfamily, which active domain is transmembrane serine/threonine kinase. Originally found in the search of bone inducing substances, it has turned out that this evolutionary conserved growth factor receptor plays important roles in bone formation and development.To undertake important roles, protein's expression of BMPR2 is strictly controlled, which one of important controlled mechanisms is by promoter, so it is fundamental to elucidate the upstream regions of the BMPR2 gene promoter.Objective: The 5"-flanking regions of the hBMPR2 promoter was isolated and analyzed to elucidate mechanism of transcription initiation in this study.Methods: The BMPR2 promoter serial 5' deletion construct inserts were generated by PCR amplification and cloned into vector pEGFP-1. Finally transient transfect these various promoter-EGFP reporter vector into MG-63 .Result: According to prediction result of approximate 3kb promoter sequences by bio-information method, a GGC repeat and some transcription factor binding sequences including Spl,MZFl,AML-la,c-Ets-,NRF-2,CdxA,CREB and TATA box was found in the sequence. The green fluorescent protein in vector pEGFP-S2 was detected in MG-63, but the green fluorescent proteins in vector pEGFP-S1 and pEGFP-S3 were not detected.Conclusion: A promoter fragment of 4450-5448bp has initiation transcriptional function, otherwise the promoter fragments of 4115-5448bp and 4757-5448bp have not initiation transcriptional function. We suppose that the transcription start site may be near TATA box and a direct GGC repeat.