Phosphatase inhibitors activate normal and defective CFTR chloride channels

Frédéric Becq, Timothy J. Jensen, Xiu-Bao D Chang, Anna Savoia, Johanna M. Rommens, Lap Chee Tsui, Manuel Buchwald, John R. Riordan, John W. Hanrahan

Research output: Contribution to journalArticle

139 Citations (Scopus)

Abstract

The cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel is regulated by phosphorylation and dephosphorylation at multiple sites. Although activation by protein kinases has been studied in some detail, the dephosphorylation step has received little attention. This report examines the mechanisms responsible for the dephosphorylation and spontaneous deactivation ('rundown') of CFTR chloride channels excised from transfected Chinese hamster ovary (CHO) and human airway epithelial cells. We report that the alkaline phosphate inhibitors bromotetramisole, 3-isobutyl-1- methylxanthine, theophylline, and vanadate slow the rundown of CFTR channel activity in excised membrane patches and reduce dephosphorylation of CFTR protein in isolated membranes. It was also found that in unstimulated cells, CFTR channels can be activated by exposure to phosphatase inhibitors alone. Most importantly, exposure of mammalian cells to phosphatase inhibitors alone activates CFTR channels that have disease-causing mutations, provided the mutant channels are present in the plasma membrane (R117H, G551D, and ΔF508 after cooling). These results suggest that CFTR dephosphorylation is dynamic and that membrane-associated phosphatase activity may be a potential therapeutic target for the treatment of cystic fibrosis.

Original languageEnglish (US)
Pages (from-to)9160-9164
Number of pages5
JournalProceedings of the National Academy of Sciences of the United States of America
Volume91
Issue number19
DOIs
StatePublished - Sep 13 1994
Externally publishedYes

Fingerprint

Cystic Fibrosis Transmembrane Conductance Regulator
Chloride Channels
Phosphoric Monoester Hydrolases
Membranes
1-Methyl-3-isobutylxanthine
Vanadates
Theophylline
Cricetulus
Cystic Fibrosis
Protein Kinases
Ovary
Epithelial Cells
Phosphates
Phosphorylation
Cell Membrane
Mutation

Keywords

  • cystic fibrosis transmembrane conductance regulator
  • rundown

ASJC Scopus subject areas

  • Genetics
  • General

Cite this

Becq, F., Jensen, T. J., Chang, X-B. D., Savoia, A., Rommens, J. M., Tsui, L. C., ... Hanrahan, J. W. (1994). Phosphatase inhibitors activate normal and defective CFTR chloride channels. Proceedings of the National Academy of Sciences of the United States of America, 91(19), 9160-9164. https://doi.org/10.1073/pnas.91.19.9160

Phosphatase inhibitors activate normal and defective CFTR chloride channels. / Becq, Frédéric; Jensen, Timothy J.; Chang, Xiu-Bao D; Savoia, Anna; Rommens, Johanna M.; Tsui, Lap Chee; Buchwald, Manuel; Riordan, John R.; Hanrahan, John W.

In: Proceedings of the National Academy of Sciences of the United States of America, Vol. 91, No. 19, 13.09.1994, p. 9160-9164.

Research output: Contribution to journalArticle

Becq, F, Jensen, TJ, Chang, X-BD, Savoia, A, Rommens, JM, Tsui, LC, Buchwald, M, Riordan, JR & Hanrahan, JW 1994, 'Phosphatase inhibitors activate normal and defective CFTR chloride channels', Proceedings of the National Academy of Sciences of the United States of America, vol. 91, no. 19, pp. 9160-9164. https://doi.org/10.1073/pnas.91.19.9160
Becq, Frédéric ; Jensen, Timothy J. ; Chang, Xiu-Bao D ; Savoia, Anna ; Rommens, Johanna M. ; Tsui, Lap Chee ; Buchwald, Manuel ; Riordan, John R. ; Hanrahan, John W. / Phosphatase inhibitors activate normal and defective CFTR chloride channels. In: Proceedings of the National Academy of Sciences of the United States of America. 1994 ; Vol. 91, No. 19. pp. 9160-9164.
@article{c78170b0d187499f8cd58082c0bb100a,
title = "Phosphatase inhibitors activate normal and defective CFTR chloride channels",
abstract = "The cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel is regulated by phosphorylation and dephosphorylation at multiple sites. Although activation by protein kinases has been studied in some detail, the dephosphorylation step has received little attention. This report examines the mechanisms responsible for the dephosphorylation and spontaneous deactivation ('rundown') of CFTR chloride channels excised from transfected Chinese hamster ovary (CHO) and human airway epithelial cells. We report that the alkaline phosphate inhibitors bromotetramisole, 3-isobutyl-1- methylxanthine, theophylline, and vanadate slow the rundown of CFTR channel activity in excised membrane patches and reduce dephosphorylation of CFTR protein in isolated membranes. It was also found that in unstimulated cells, CFTR channels can be activated by exposure to phosphatase inhibitors alone. Most importantly, exposure of mammalian cells to phosphatase inhibitors alone activates CFTR channels that have disease-causing mutations, provided the mutant channels are present in the plasma membrane (R117H, G551D, and ΔF508 after cooling). These results suggest that CFTR dephosphorylation is dynamic and that membrane-associated phosphatase activity may be a potential therapeutic target for the treatment of cystic fibrosis.",
keywords = "cystic fibrosis transmembrane conductance regulator, rundown",
author = "Fr{\'e}d{\'e}ric Becq and Jensen, {Timothy J.} and Chang, {Xiu-Bao D} and Anna Savoia and Rommens, {Johanna M.} and Tsui, {Lap Chee} and Manuel Buchwald and Riordan, {John R.} and Hanrahan, {John W.}",
year = "1994",
month = "9",
day = "13",
doi = "10.1073/pnas.91.19.9160",
language = "English (US)",
volume = "91",
pages = "9160--9164",
journal = "Proceedings of the National Academy of Sciences of the United States of America",
issn = "0027-8424",
number = "19",

}

TY - JOUR

T1 - Phosphatase inhibitors activate normal and defective CFTR chloride channels

AU - Becq, Frédéric

AU - Jensen, Timothy J.

AU - Chang, Xiu-Bao D

AU - Savoia, Anna

AU - Rommens, Johanna M.

AU - Tsui, Lap Chee

AU - Buchwald, Manuel

AU - Riordan, John R.

AU - Hanrahan, John W.

PY - 1994/9/13

Y1 - 1994/9/13

N2 - The cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel is regulated by phosphorylation and dephosphorylation at multiple sites. Although activation by protein kinases has been studied in some detail, the dephosphorylation step has received little attention. This report examines the mechanisms responsible for the dephosphorylation and spontaneous deactivation ('rundown') of CFTR chloride channels excised from transfected Chinese hamster ovary (CHO) and human airway epithelial cells. We report that the alkaline phosphate inhibitors bromotetramisole, 3-isobutyl-1- methylxanthine, theophylline, and vanadate slow the rundown of CFTR channel activity in excised membrane patches and reduce dephosphorylation of CFTR protein in isolated membranes. It was also found that in unstimulated cells, CFTR channels can be activated by exposure to phosphatase inhibitors alone. Most importantly, exposure of mammalian cells to phosphatase inhibitors alone activates CFTR channels that have disease-causing mutations, provided the mutant channels are present in the plasma membrane (R117H, G551D, and ΔF508 after cooling). These results suggest that CFTR dephosphorylation is dynamic and that membrane-associated phosphatase activity may be a potential therapeutic target for the treatment of cystic fibrosis.

AB - The cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel is regulated by phosphorylation and dephosphorylation at multiple sites. Although activation by protein kinases has been studied in some detail, the dephosphorylation step has received little attention. This report examines the mechanisms responsible for the dephosphorylation and spontaneous deactivation ('rundown') of CFTR chloride channels excised from transfected Chinese hamster ovary (CHO) and human airway epithelial cells. We report that the alkaline phosphate inhibitors bromotetramisole, 3-isobutyl-1- methylxanthine, theophylline, and vanadate slow the rundown of CFTR channel activity in excised membrane patches and reduce dephosphorylation of CFTR protein in isolated membranes. It was also found that in unstimulated cells, CFTR channels can be activated by exposure to phosphatase inhibitors alone. Most importantly, exposure of mammalian cells to phosphatase inhibitors alone activates CFTR channels that have disease-causing mutations, provided the mutant channels are present in the plasma membrane (R117H, G551D, and ΔF508 after cooling). These results suggest that CFTR dephosphorylation is dynamic and that membrane-associated phosphatase activity may be a potential therapeutic target for the treatment of cystic fibrosis.

KW - cystic fibrosis transmembrane conductance regulator

KW - rundown

UR - http://www.scopus.com/inward/record.url?scp=0028577602&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0028577602&partnerID=8YFLogxK

U2 - 10.1073/pnas.91.19.9160

DO - 10.1073/pnas.91.19.9160

M3 - Article

VL - 91

SP - 9160

EP - 9164

JO - Proceedings of the National Academy of Sciences of the United States of America

JF - Proceedings of the National Academy of Sciences of the United States of America

SN - 0027-8424

IS - 19

ER -