Isolation and characterization of the 5'-flanking regulatory region of the human natriuretic peptide receptor C gene.
Phenotypic modulation of vascular smooth muscle cells (SMCs) plays a central role in the pathogenesis of atherosclerosis. Natriuretic peptide receptor-C (NPR-C) is highly expressed in vascular SMCs in the experimental arteriosclerotic neointimal area as well as in cultured SMCs, suggesting that increased expression of the NPR-C gene is related to the phenotypic alteration of vascular SMCs. To elucidate the molecular mechanisms and to identify the essential DNA sequences in NPR-C gene expression, a genomic clone containing over 8 kilobases of the 5'-flanking region of the human NPR-C gene has been isolated. Sequence analysis revealed that a number of putative regulatory elements including unusual tandem repeated AP-2-like sequences were observed in the 5'-flanking region. Primer extension and ribonuclease protection analyses revealed that transcription of the human NPR-C gene starts from two major regions. Promoter analysis using deletion constructs in human cells, highly producing NPR-C transcripts, showing that the region (from - 33 to + 13 relative to the transcription start point) had a potential promoter activity suggested that the region from -33 to + 13, containing a pyrimidine-rich stretch composed of four CTTTTT-repeated sequences, is sufficient for the proximal promoter activity. Moreover, three distinct DNA sequences surrounding the transcription start site (P1, from -60 to -33; P2, from + 14 to +40; P3, from +41 to +66) were revealed to be functional as a cis-acting positive enhancer, and a nuclear protein(s) from the human cells was demonstrated to specifically bind to the sequences, respectively. However, promoter analysis has shown that the P2 and P3 sequences could not activate the human NPR-C promoter in a synergistic manner. On the basis of deoxyribonuclease I footprinting analysis showing that a DNA element from +48 to +60 within the P3 sequence is preferentially protected, the P3 sequence appears to contain a potential regulatory element involved in NPR-C gene expression. The present study demonstrated the structure of the 5'-regulatory region of the human NPR-C gene and multiple cis-acting positive sequences closely located around the transcription start points with an important role in regulation of human NPR-C gene expression.
Yanaka
N
N
Lead Generation Research Laboratory, Tanabe Seiyaku Co., Osaka, Japan.
Kotera
J
J
Omori
K
K
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D005786:Gene Expression Regulation; D006162:Guanylate Cyclase / Q000032:analysis / Q000235:genetics*; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017461:Receptors, Atrial Natriuretic Factor / Q000032:analysis / Q000235:genetics*; D014158:Transcription, Genetic
D012333:RNA, Messenger; D006162:Guanylate Cyclase; D017461:Receptors, Atrial Natriuretic Factor; C073616:atrial natriuretic factor receptor C