The transcription factor Wilms tumor 1 regulates matrix metalloproteinase-9 through a nitric oxide-mediated pathway.
Matrix metalloproteinase-9 (MMP-9) is released by human lung epithelial cells (LEC) in conditions such as asthma and chronic obstructive pulmonary disease and expression of MMP-9 correlates with the severity of these disorders. MMP-9 production has been reported to be regulated by a NO/soluble guanylate cyclase-dependent pathway. Transcriptional regulation of this enzyme, however, is poorly understood. Using phylogenetic analysis, we observed a highly conserved sequence in the 5' flanking region of the MMP-9 gene containing binding sites for the transcription factor Wilms tumor 1 (WT1). We confirmed the presence of WT1 in human LEC and that treatment with TNF or a mixture containing LPS, PMA, and IFN-gamma resulted in translocation of WT1 from the nucleus to the cytosol. This translocation coincided with increased expression of MMP-9 and could be blocked by inhibitors of the NO/soluble guanylate cyclase pathway. WT1 knockdown using small-interfering RNA up-regulated MMP-9 expression in the presence of the NO synthase inhibitor 1400W. Using either WT1 pulldown with probes for the conserved region of the MMP-9 promoter or chromatin immunoprecipitation, we confirmed WT1 binding to the MMP-9 promoter. These findings indicate WT1 is a repressor of MMP-9, regulated by a NO-mediated pathway in human LEC. To our knowledge, this is the first report of WT1 regulating MMP-9 expression. Further study is needed to determine whether clinical conditions exhibiting tissue remodeling, such as asthma and/or chronic obstructive pulmonary disease, demonstrate reduced levels of WT1 or its repressor activity.
Marcet-Palacios
Marcelo
M
Glaxo-Heritage Asthma Research Laboraotries, Heritage Medical Research Center, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.
Ulanova
Marina
M
Duta
Florentina
F
Puttagunta
Lakshmi
L
Munoz
Samira
S
Gibbings
Derrick
D
Radomski
Marek
M
Cameron
Lisa
L
Mayers
Irvin
I
Befus
A Dean
AD
D002460:Cell Line; D002461:Cell Line, Transformed; D045744:Cell Line, Tumor; D054746:Cyclic AMP-Dependent Protein Kinase Type II; D017868:Cyclic AMP-Dependent Protein Kinases / Q000502:physiology; D004789:Enzyme Activation / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic; D006162:Guanylate Cyclase / Q000502:physiology; D006801:Humans; D008168:Lung / Q000166:cytology / Q000201:enzymology / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D061965:Matrix Metalloproteinase Inhibitors; D009569:Nitric Oxide / Q000502:physiology*; D052247:Nitric Oxide Synthase Type II / Q000096:biosynthesis / Q000502:physiology; D011401:Promoter Regions, Genetic; D011480:Protease Inhibitors / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding / Q000235:genetics; D018160:Receptors, Cytoplasmic and Nuclear / Q000502:physiology; D012097:Repressor Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism / Q000502:physiology*; D020545:Respiratory Mucosa / Q000166:cytology / Q000201:enzymology / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics; D000071756:Soluble Guanylyl Cyclase; D014409:Tumor Necrosis Factor-alpha / Q000502:physiology; D025721:WT1 Proteins / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000378:metabolism / Q000502:physiology*
D061965:Matrix Metalloproteinase Inhibitors; D011480:Protease Inhibitors; D018160:Receptors, Cytoplasmic and Nuclear; D012097:Repressor Proteins; D014409:Tumor Necrosis Factor-alpha; D025721:WT1 Proteins; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II; D054746:Cyclic AMP-Dependent Protein Kinase Type II; D017868:Cyclic AMP-Dependent Protein Kinases; D020780:Matrix Metalloproteinase 9; D006162:Guanylate Cyclase; D000071756:Soluble Guanylyl Cyclase