Progression of Coronary Atherosclerosis Is Associated with a Common Genetic Variant of the Human Stromelysin-1 Promoter Which Results in Reduced Gene Expression

Abstract

There is a common polymorphism in the promoter sequence of the human stromelysin-1 gene, with one allele having a run of six adenosines (6A) and the other five adenosines (5A). We have previously reported, in a 3-year follow-up study of patients with coronary atherosclerosis, that those patients who are homozygous for the 6A allele show a more rapid progression of the disease. In this study, we have investigated whether the 5A/6A promoter polymorphism plays a role in the regulation of stromelysin-1 gene expression. In transient transfection experiments, a stromelysin-1 promoter construct with 6A at the polymorphic site was found to express less of the chloramphenicol acetyltransferase reporter gene than a construct containing 5A. Electrophoretic mobility shift assay and DNase I footprinting revealed the interaction of one or more nuclear protein(s) with the DNA sequence at the 5A/6A polymorphic site. The binding of one of the nucleoprotein factors was more readily detectable with an oligonucleotide probe corresponding to the 6A allele as compared with a probe corresponding to the 5A allele. Replacing the core binding sequence with a random DNA sequence abolished the interaction between the nuclear protein(s) and the probe and also increased reporter gene expression in transiently transfected cells. Thus, the common 5A/6A polymorphism of the human stromelysin-1 promoter appears to play an important role in regulating stromelysin-1 gene expression and may be involved in the progression of coronary heart disease.Stromelysin-1 is a key member of the matrix metalloproteinase (MMP) 1 family, with a broad substrate specificity. It can degrade types II, IV, and IX collagen, proteoglycans, laminin, fibronectin, gelatins, and elastin (1-3). In addition, stromelysin-1 can also activate other MMPs such as collagenase, matrilysin, and gelatinase B, rendering stromelysin-1 crucial in connective tissue remodeling (4 -6). Expression of stromelysin-1 is primarily regulated at the level of transcription, where the promoter of the gene responds to various stimuli, including growth factors, cytokines, tumor promoters, and oncogene products (7-10). The regulatory effects of such stimuli are mediated through a number of cis-elements located in the stromelysin-1 promoter. For instance, the activator protein-1 binding site at positions Ϫ63 to Ϫ70 is necessary for the basal expression of the gene and is also involved in interleukin-1 induction (11-13). A promoter element located between Ϫ1218 and Ϫ1202 is responsible for the induction of stromelysin-1 expression by platelet-derived growth factor B/B (14, 15), whereas three sequences that share strong homology with the glucocorticoid-responsive consensus element are likely to be involved in the dexamethasone suppression (16).Over the last few years, MMPs have been implicated in the connective tissue remodeling during atherogenesis (17)(18)(19)(20)(21)(22). By in situ mRNA hybridization, we originally demonstrated the presence of stromelysin-1 in coronary atherosclerotic plaques (18). E...

Promoter polymorphism of the matrix metalloproteinase 3 gene is associated with regurgitation and left ventricular remodelling in mitral valve prolapse patients

“…Studies by Ye et al indicated that MMP-3 promoter with the 5A allele has greater activity than the 6A allele [11,17]. Others have shown that the MMP-3 gene transcript in aorta and protein expression in skin are higher in individuals with the 5A/5A than the 5A/6A or 6A/6A genotypes [23].…”

“…A number of sequence variants have been identified in the promoter region of this gene [17]. Further sequence analysis revealed that the 5A/6A polymorphism was firstly identified in the reverse orientation of the gene [11,18] and therefore the correct nomenclature and position of this polymorphism should be -1612 5T/6T (Genbank sequence accession no. AF405705).…”

“…Two single nucleotide polymorphisms ( -1607 1G/2G and -1612 5A/6A) have been identified in the promoter region of the MMP-1 and MMP-3 genes respectively and are known to have functional effects on promoter activity [10,11]. Since MMPs play crucial roles in the tissue remodelling process in the heart, it is plausible that these polymorphisms might affect the level of gene expression and hence might influence the LV remodelling process in patients with MVP.…”

Matrix metalloproteinase-3 (MMP-3) -1612 5A/6A promoter polymorphism in coronary artery disease in Indian population

“…A single nucleotide polymorphism (SNP) has been identified in the promoter region of the MMP-3 gene, located 1612 base pair (bp) upstream of the transcription start site with one allele containing a run of five adenosines (5A), and the other allele containing a run of six adenosines (6A) (8). Transient transfection experiments have indicated that the 5A-allele expresses a two fold higher activity of the reporter gene than does the 6A-allele, a finding suggesting that carriers of the 5A-allele exhibit a higher MMP-3 promoter activity (9). There is also clinical evidence that MMP-3-1612 5A/6A promoter polymorphism influences atherosclerosis in carotid arteries (10) the aorta (11) and coronary arteries (9).…”

“…Transient transfection experiments have indicated that the 5A-allele expresses a two fold higher activity of the reporter gene than does the 6A-allele, a finding suggesting that carriers of the 5A-allele exhibit a higher MMP-3 promoter activity (9). There is also clinical evidence that MMP-3-1612 5A/6A promoter polymorphism influences atherosclerosis in carotid arteries (10) the aorta (11) and coronary arteries (9).…”