The human gene for renin-binding protein

Abstract

The human renin-binding protein (RnBP) gene was isolated from a human placental genomic library and characterized. The gene spans about 10 kilobases and consists of 11 exons separated by 10 introns. The 5'-flanking region and the exon-intron boundaries were sequenced. Residue G* in 5'-CGAG*TGG-3' was identified as the major transcription initiation site, and "GC" boxes were found in the vicinity of the cap site. No typical "TATA" or "CCAAT" box exists in the 5'-flanking region. The hydrophobic domain followed by a leucine-zipper motif in RnBP is encoded by the sixth exon. A fragment of the human RnBP gene (nucleotides -739 to +244) linked to the chloramphenicol acetyltransferase gene was transfected into human Wilms' tumor G401 and mouse L929 cells. The expression of this chimeric gene in G401 cells was 4-fold higher than that in L929 cells, the tissue-specific regulation of RnBP gene expression thus being suggested. The promoter for the RnBP gene was shown to be localized in nucleotides -35 to +244 on assaying of the promoter activity using deletion mutants of the chimeric constructs. The RnBP gene was found to be located in human chromosome X by means of polymerase chain reaction of hybrid DNAs from human and hamster somatic cells.