Characterization of the human CR1 gene promoter

Abstract

Abbreviations: CR1, Complement receptor type 1; CR2, complement receptor type 2; DAF, decay accelerating factor; MCP, membrane cofactor protein; C4BR C4 binding protein,; DMSO, Dime@ sulfoxide; MMLV-RTase, Moloney murine lekemia virus reverse transcriptase; HPRT, hypoxanthine phosphoribosyltransferase. SUMMARY:The human CR1 is a single chain membrane glycoprotein that is a member of the group of regulators of the complement activation system. In order to clarify the regulatory mechanisms of human CR1 gene expression, the 5'-flanking region of the human CR1 gene was isolated and its promoter was characterized. The CR1 expression was found to be transcriptionally up-regulated in HL60 cells by stimulation with DMSO. The cloned CR1 gene promoter was sequenced and computer analyzed. The potential promoter region lacks a distinct TATA box sequence. The transcription initiation site was determined by primer extension and several possible regulatory elements for transcription were found in the promoter region.

Promoter structure and transcriptional activity of human complement receptor type I (CR1) gene

“…We had previously shown that the basal human CR1 promoter is located within 376 nucleotides upstream of the transcription initiation site (Kim et al, 1999a) and identified several potential transcription factor-binding sites (Fig. 1).…”

“…The HEL cells were transfected with a reporter construct by electroporation and relative luciferase activities were assayed as described previously (Kim et al, 1999a). Compositions of the plasmids used are described in the figure legend.…”

“…This promoter has many features classically observed in housekeeping genes including a typical CpG island and TATA-less promoter. Several potential transcription factor binding sites, such as CArG (Funkhouser et al, 2000), Sp1, ets, inverted CCAAT box, and AML1 binding site (Kim et al, 1999a;Kim et al, 1999b;Rho et al, 2002) were also identified. In this context, here, we set out to further elucidate the promoter elements involved in regulation of human CR1 gene expression.…”

P2‐030: Investigating the Role of Clu, Picalm, and Cr1 in Alzheimer's Disease

“…They studied a region of ~2kb 5' of the gene, and found no evidence of a typical TATA type promoter sequence, but did find a CAAT-box type sequence (TCAAAA, which had previously been shown to be capable of acting as a CAAT-box (Kunz et al 1989)), which was observed around position -54 to -49. The 5' flanking region was also found to contain a GC-rich region, particularly high in CpG dinucleotides (Kim et al 1999).…”

“…Due to the different expression levels of CR1, Kim et al (Kim et al 1999) sought to identify the regulatory elements which may control this expression within the promoter of the CR1 gene. They studied a region of ~2kb 5' of the gene, and found no evidence of a typical TATA type promoter sequence, but did find a CAAT-box type sequence (TCAAAA, which had previously been shown to be capable of acting as a CAAT-box (Kunz et al 1989)), which was observed around position -54 to -49.…”