title: Molecular Mechanisms Underlying the Regulation of the MFG-E8 Gene Promoter Activity in Physiological and Inflammatory Conditions.
abstract: Milk fat globule-EGF factor 8 (MFG-E8) is expressed by macrophages and plays an important role in attenuating inflammation and maintaining tissue homeostasis. Previously, we and others found that lipopolysaccharide (LPS) inhibits MFG-E8 gene expression in macrophages. Here, we characterized the 5'-flanking region of the mouse MFG-E8 gene. To functionally analyze the upstream regulatory region of the MFG-E8 gene, a series of luciferase reporter gene constructs containing deleted or mutated regulatory elements were prepared. Using the luciferase assay, we revealed that Sp1 binding motifs within the proximal promoter region were necessary for full activity of the MFG-E8 promoter, whereas AP-1 like binding sequence at -372 played a role in governing the promoter activity at a homeostatic level. With chromatin immunoprecipitation assay, we showed that Sp1 and c-Jun physically interact with the MFG-E8 promoter region in vivo. In addition, Sp1 was found to regulate the MFG-E8 promoter activity positively and c-Jun negatively. Furthermore, we demonstrated that LPS inhibited MFG-E8 promoter activity via targeting Sp1 and AP-1-like motifs in the 5'-flanking region. Collectively, our data indicate that Sp1 and AP-1-related factors are involved in the regulation of MFG-E8 gene transcription by targeting their binding sites in the 5'-flanking region under physiological and inflammatory states.
authors.affiliation: Center for Intestinal and Liver Inflammation Research, Stanley Manne Children's Research Institute, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois.|Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
authors.forename: Xiao
authors.initials: X
authors.lastname: Wang
authors.affiliation: Center for Intestinal and Liver Inflammation Research, Stanley Manne Children's Research Institute, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois.|Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
authors.forename: Heng-Fu
authors.initials: HF
authors.lastname: Bu
authors.affiliation: Center for Intestinal and Liver Inflammation Research, Stanley Manne Children's Research Institute, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois.|Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
authors.forename: Shirley X L
authors.initials: SX
authors.lastname: Liu
authors.affiliation: Center for Intestinal and Liver Inflammation Research, Stanley Manne Children's Research Institute, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois.|Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
authors.forename: Isabelle G
authors.initials: IG
authors.lastname: De Plaen
authors.affiliation: Center for Intestinal and Liver Inflammation Research, Stanley Manne Children's Research Institute, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois.|Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.|Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.|Department of Research & Development, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois.
authors.forename: Xiao-Di
authors.initials: XD
authors.lastname: Tan
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D001665:Binding Sites / Q000187:drug effects; D002478:Cells, Cultured; D005786:Gene Expression Regulation / Q000187:drug effects; D007249:Inflammation / Q000139:chemically induced* / Q000235:genetics / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D017737:Macrophages, Peritoneal / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D008894:Milk Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000187:drug effects; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism*; D016329:Sp1 Transcription Factor / Q000378:metabolism*
chemical_list: D000954:Antigens, Surface; D008070:Lipopolysaccharides; C490919:Mfge8 protein, mouse; D008894:Milk Proteins; D016755:Proto-Oncogene Proteins c-jun; D016329:Sp1 Transcription Factor
keywords: GENE REGULATION; INFLAMMATION; MACROPHAGES; TRANSCRIPTION FACTORS