Reduced ets domain-containing protein Elk1 promotes pulmonary fibrosis via increased integrin alpha v beta 6 expression
Author(s)
Type
Journal Article
Abstract
Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic lung disease with high mortality. Active TGFβ1 is considered central to the pathogenesis of IPF. A major mechanism of TGFβ1 activation in the lung involves the epithelially restricted αvβ6 integrin. Expression of the αvβ6 integrin is dramatically increased in IPF. How αvβ6 integrin expression is regulated in the pulmonary epithelium is unknown. Here we identify a region in the β6 subunit gene (ITGB6) promoter acting to markedly repress basal gene transcription, which responds to both the Ets domain-containing protein Elk1 (Elk1) and the glucocorticoid receptor (GR). Both Elk1 and GR can regulate αvβ6 integrin expression in vitro. We demonstrate Elk1 binding to the ITGB6 promoter basally and that manipulation of Elk1 or Elk1 binding alters ITGB6 promoter activity, gene transcription, and αvβ6 integrin expression. Crucially, we find that loss of Elk1 causes enhanced Itgb6 expression and exaggerated lung fibrosis in an in vivo model of fibrosis, whereas the GR agonist dexamethasone inhibits Itgb6 expression. Moreover, Elk1 dysregulation is present in epithelium from patients with IPF. These data reveal a novel role for Elk1 regulating ITGB6 expression and highlight how dysregulation of Elk1 can contribute to human disease.
Date Issued
2016-04-29
Date Acceptance
2016-04-01
Citation
Journal of Biological Chemistry, 2016, 291 (18), pp.9540-9553
ISSN
0021-9258
Publisher
American Society for Biochemistry and Molecular Biology
Start Page
9540
End Page
9553
Journal / Book Title
Journal of Biological Chemistry
Volume
291
Issue
18
Copyright Statement
Author’s Choice—Final version free via Creative Commons CC-BY license.
License URL
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000375602300014&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Subjects
Science & Technology
Life Sciences & Biomedicine
Biochemistry & Molecular Biology
GROWTH-FACTOR-BETA
LUNG EPITHELIAL-CELLS
TRANSCRIPTIONAL ACTIVATION
LIVER FIBROSIS
INTEGRIN-ALPHA-V-BETA-6
INFLAMMATION
RECEPTOR
DIFFERENTIATION
DEGRADATION
INHIBITION
Publication Status
Published