title: Identifying the regulative role of NF-κB binding sites within promoter region of human matrix metalloproteinase 9 (mmp-9) by TNF-α induction.
abstract: Matrix metalloproteinase 9 (MMP-9), a member of MMP family, is involved in many physiological processes, including cardiovascular disease (CVD). Tumor necrosis factor-α (TNF-α) is considered a cytokine with pleiotropic biological capabilities and leads to the process of CVD when TNF-α is abnormally released and stimulates MMP-9 expression and activation. In this study, we investigated the molecular mechanism of TNF-α-regulated MMP-9 expression. The experimental results confirm that TNF-α could upregulate MMP-9 expression in heart myoblast H9c2 cells of rat. To evaluate the MMP-9 regulation at transcriptional level, a DNA fragment of 2.2 kb (-2168/+18) of human mmp-9 promoter region was cloned and constructed in a vector of luciferase reporter gene. The 2.2-kb sequences were identified as having three candidate nuclear factor-κ B (NF-κB) binding sites: NF-κB I (-1418/-1409), NF-κB II (-626/-617), and NF-κB III (-353/-345). A series of reporter vectors with the mutated NF-κB sites of mmp-9 promoter sequences were constructed and transfected into H9c2 cells. The results show that the NF-κB II binding site (-626/-617) within the promoter region of mmp-9 plays a key role in upregulation of mmp-9 expression by TNF-α induction. In addition, we also first identified that the NF-κB I, similar to c-Rel, might be one of the NF-κB families to regulate mmp-9 expression.
authors.affiliation: Department of BioAgricultural Science, National Chia Yi University, 300 Syuefu Rd., Chiayi 60004, Taiwan. htwu@mail.ncyu.edu.tw
authors.forename: Hsi Tien
authors.initials: HT
authors.lastname: Wu
authors.forename: Syu Sheng
authors.initials: SS
authors.lastname: Sie
authors.forename: Tang Ching
authors.initials: TC
authors.lastname: Kuan
authors.forename: Chih Sheng
authors.initials: CS
authors.lastname: Lin
mesh_terms: D001483:Base Sequence; D001665:Binding Sites; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics*; D006801:Humans; D020780:Matrix Metalloproteinase 9 / Q000235:genetics*; D008969:Molecular Sequence Data; D016328:NF-kappa B / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics*; D011485:Protein Binding; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics*; D015854:Up-Regulation / Q000235:genetics
chemical_list: D016328:NF-kappa B; D014409:Tumor Necrosis Factor-alpha; D020780:Matrix Metalloproteinase 9