Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2004-7-21
pubmed:abstractText
Transforming growth factor beta (TGFbeta) is a multifunctional cytokine with effects on many cell types. We recently showed that in addition to epithelial barrier enhancing properties, TGFbeta causes diminished cAMP-driven chloride secretion in colonic epithelia, in a manner that is p38 MAPK-dependent. In this study, we sought to further delineate the mechanism behind TGFbeta diminution of chloride secretion. Using colonic and kidney epithelial cell lines, we found that exposure to TGFbeta causes dramatic changes in the expression and localization of the apical membrane chloride channel, cystic fibrosis transmembrane conductance regulator (CFTR). In TGFbeta-treated colonic epithelia (T84 and HT-29), CFTR mRNA was significantly reduced 2-24 h post-cytokine exposure. At a time consistent with decreased colonic epithelial secretory responses (16 h), TGFbeta treatment caused diminished intracellular CFTR protein expression (confocal microscopy) and reduced channel expression in the apical membrane during stimulated chloride secretion (biotinylation assay). In comparison, polarized kidney epithelia (MDCK) treated with TGFbeta displayed similarly reduced secretory responses to cAMP stimulating agents; however, a perinuclear accumulation of CFTR was observed, contrasting the diffuse cytoplasmic CFTR expression of control cells. Our data indicate that TGFbeta has profound effects on the expression and subcellular localization of an important channel involved in cAMP-driven chloride secretion, and thus suggest TGFbeta represents a key regulator of fluid movement.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0014-4827
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
298
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
473-84
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:15265695-Animals, pubmed-meshheading:15265695-Cell Line, pubmed-meshheading:15265695-Cell Membrane, pubmed-meshheading:15265695-Cell Membrane Permeability, pubmed-meshheading:15265695-Cell Nucleus, pubmed-meshheading:15265695-Chlorides, pubmed-meshheading:15265695-Cyclic AMP, pubmed-meshheading:15265695-Cystic Fibrosis Transmembrane Conductance Regulator, pubmed-meshheading:15265695-Cytoplasm, pubmed-meshheading:15265695-Cytoskeleton, pubmed-meshheading:15265695-Dogs, pubmed-meshheading:15265695-Dose-Response Relationship, Drug, pubmed-meshheading:15265695-Down-Regulation, pubmed-meshheading:15265695-Epithelial Cells, pubmed-meshheading:15265695-Humans, pubmed-meshheading:15265695-Protein Transport, pubmed-meshheading:15265695-RNA, Messenger, pubmed-meshheading:15265695-Reaction Time, pubmed-meshheading:15265695-Transforming Growth Factor beta, pubmed-meshheading:15265695-Water-Electrolyte Balance
pubmed:year
2004
pubmed:articleTitle
TGFbeta down-regulation of the CFTR: a means to limit epithelial chloride secretion.
pubmed:affiliation
Intestinal Disease Research Programme, Department of Pathology and Molecular Medicine, McMaster University, HSC-3N5C, Hamilton, Ontario, Canada L8N 3Z5.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't