Linked Life Data

16413502

Source:http://linkedlifedata.com/resource/pubmed/id/16413502

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2006-1-24
pubmed:abstractText
Cystic fibrosis (CF), an autosomal recessive disorder, is caused by the disruption of biosynthesis or the function of a membrane cAMP-activated chloride channel, CFTR. CFTR regulatory mechanisms include recruitment of channel proteins to the cell surface from intracellular pools and by protein-protein interactions. Rab proteins are small GTPases involved in regulated trafficking controlling vesicle docking and fusion. Rab4 controls recycling events from endosome to the plasma membrane, fusion, and degradation. The colorectal cell line HT-29 natively expresses CFTR and responds to cAMP stimulation with an increase in CFTR-mediated currents. Rab4 over-expression in HT-29 cells inhibits both basal and cAMP-stimulated CFTR-mediated currents. GTPase-deficient Rab4Q67L and GDP locked Rab4S22N both inhibit channel activity, which appears characteristically different. Active status of Rab4 was confirmed by GTP overlay assay, while its expression was verified by Western blotting. The pull-down and immunoprecipitation experiments suggest that Rab4 physically interacts with CFTR through protein-protein interaction. Biotinylation with cell impermeant NHS-Sulfo-SS-Biotin implies that Rab4 impairs CFTR expression at cell surface. The enhanced cytosolic CFTR indicates that Rab4 expression restrains CFTR appearance at the cell membrane. The study suggests that Rab4 regulates the channel through multiple mechanisms that include protein-protein interaction, GTP/GDP exchange, and channel protein trafficking. We propose that Rab4 is a dynamic molecule with a significant role in CFTR function.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-291X
pubmed:author
pubmed:issnType
Print
pubmed:day
3
pubmed:volume
341
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
184-91
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Rab4GTPase modulates CFTR function by impairing channel expression at plasma membrane.
pubmed:affiliation
Center for Cell and Molecular Biology, Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, NJ 07030, USA. ssaxena@stevens.edu
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural