Identification of Nuclear Factor-κB Responsive Element within the Neuronal Nitric Oxide Synthase Exon If-specific Promoter  

作　　者：Yinghui LI Guangyu LI Chunyi LI Yanyan ZHAO 

机构地区：[1]Department of Medical Genetics, China Medical University, Shenyang 110001, China [2]Department of Neurosurgery, First Affiliated Hospital, China Medical University, Shenyang 110001, China

出　　处：《Acta Biochimica et Biophysica Sinica》2007年第4期247-254,共8页生物化学与生物物理学报（英文版）

基　　金：This work was supported by the grants from the National Natural Science Foundations of China(No.30400463 and 30370785)

摘　　要：Transcriptional regulation of the neuronal nitric oxide synthase gene （nNOS） is particularly complex as 12 distinct transcripts derived from different first exons are expressed in a tissue- and cellspecific manner. The exon If mRNA is relatively highly expressed in nervous system and relies upon exon If-specific promoter activity. Using conventional and real-time reverse transcription-polymerase chain reaction, we found exon If mRNA was the major transcript of the nNOS gene in human neuroblastoma SK-N-SH cells. We analyzed a 1090 bp fragment of If promoter by TRANSFAC-TESS and Match softwares and luciferase assay, and found an important positive transcriptional regulation region that contained a putative nuclear factor （NF）-κB binding site. Subsequently, using electrophoresis mobility shift and chromatin immunoprecipitation assays, we identified this site to be the NF-κB responsive element, a crucial positive regulator in the activation of the nNOS If promoter. Taken together, our study identified an NF-κB responsive element within nNOS If promoter and showed that it plays an important role in the transactivation of nNOS If mRNA, the major transcript of nNOS in SK-N-SH cells.Transcriptional regulation of the neuronal nitric oxide synthase gene （nNOS） is particularly complex as 12 distinct transcripts derived from different first exons are expressed in a tissue- and cellspecific manner. The exon If mRNA is relatively highly expressed in nervous system and relies upon exon If-specific promoter activity. Using conventional and real-time reverse transcription-polymerase chain reaction, we found exon If mRNA was the major transcript of the nNOS gene in human neuroblastoma SK-N-SH cells. We analyzed a 1090 bp fragment of If promoter by TRANSFAC-TESS and Match softwares and luciferase assay, and found an important positive transcriptional regulation region that contained a putative nuclear factor （NF）-κB binding site. Subsequently, using electrophoresis mobility shift and chromatin immunoprecipitation assays, we identified this site to be the NF-κB responsive element, a crucial positive regulator in the activation of the nNOS If promoter. Taken together, our study identified an NF-κB responsive element within nNOS If promoter and showed that it plays an important role in the transactivation of nNOS If mRNA, the major transcript of nNOS in SK-N-SH cells.

关 键 词：NNOS NF-ΚB TRANSACTIVATION nervous system 

分 类 号：Q593.2[生物学—生物化学]