King's College London

Research portal

Transcriptional regulation of the NADPH oxidase isoform, Nox1, in colon epithelial cells: Role of GATA-binding factor(s)

Research output: Contribution to journalArticle

A C Brewer, E C Sparks, A M Shah

Original languageEnglish
Pages (from-to)260 - 274
Number of pages15
JournalFree Radical Biology and Medicine
Volume40
Issue number2
DOIs
Publication statusPublished - 15 Jan 2006

King's Authors

Abstract

Nonphagocytic NADPH oxidases (Noxs) are major sources of reactive oxygen species (ROS) and exist as a family of isoenzymes with tissue-restricted expression and functions. Nox1, expressed in colon epithelium and vascular smooth muscle, is suggested to be involved in innate immune defense and cell growth or proliferation. The transcriptional regulation of Nox1 appears to be particularly important in the modulation of its activity but the underlying mechanisms are unknown. Here we have identified the functional Nox1 promoter in human colon epithelial Caco-2 cells, and show that a 520-bp genomic fragment encompassing the CAP site is sufficient to direct high levels of expression of a linked reporter gene in these cells. Deletion analyses together with electrophoretic mobility-shift assays (EMSAs) suggest that maximal promoter activity is dependent oil a GATA-binding site, conserved between human and Mouse, Within the proximal promoter region. The ability of mouse GATA factors to transactivate the Nox1 promoter was demonstrated in Cos-7 cells and site-directed mutagenesis of the conserved GATA-binding site further demonstrates that the regulation of Nox1 transcription is mediated by the direct binding of a GATA factor to the Nox1 proximal promoter. We also identified more distal, upstream regions which act to repress significantly expression from the Nox1 promoter. (c) 2005 Elsevier Inc. All rights reserved

View graph of relations

© 2018 King's College London | Strand | London WC2R 2LS | England | United Kingdom | Tel +44 (0)20 7836 5454