Involvement of Sp1 elements in the promoter activity of genes affected in keratoconus.

摘要: PURPOSE: Keratoconus is a progressive disease that thins and scars the corneal stroma. In keratoconus corneas, levels of degradative enzymes, including lysosomal acid phosphatase (LAP) cathepsin B, are elevated, those inhibitors alpha1-proteinase inhibitor (alpha 1-PI) alpha 2-macroglobulin 2-M) reduced, especially in epithelial layer. An increased expression transcription factor Sp1 was also demonstrated. The role regulation genes affected examined this study. METHODS: DNA segments, containing 5'-flanking promoter sequences 1-PI, LAP, 2-M were ligated into secreted alkaline (SEAP) reporter gene vector. These constructs, along with pSV beta-galactosidase control vector, transfected cultured human stromal cells skin fibroblasts. Cotransfection vector performed parallel. SEAP enzyme activities assayed. RESULTS: cells, as 1-PI activity suppressed by cotransfection pPacSp1. promoters functional whereas these much lower experiments indicated up- or downregulation observed keratoconus-affected corneas not mediated Sp1. CONCLUSIONS: results support theory epithelium, stroma, involved keratoconus. upstream Sp1-mediated may be key event development.