NHERF1 Overexpression-dependent Increase of Cytoskeleton Organization Is Fundamental in the Rescue of F508del CFTR in Human Airway CFBE41o- Cells

Abstract

We have demonstrated that Na+/H+ exchanger regulatory factor 1 (NHERF1) overexpression in CFBE41o-cells induces a significant redistribution of F508del cystic fibrosis transmembrane conductance regulator (CFTR) from the cytoplasm to the apical membrane and rescues CFTR-dependent chloride secretion. Here, we observe that CFBE41o-monolayers displayed substantial disassembly of actin filaments and that overexpression of wild-type (wt) NHERF1 but not NHERF1-Delta Ezrin-Radixin-Moesin (ERM) increased F-actin assembly and organization. Furthermore, the dominant-negative band Four-point one, Ezrin, Radixin, Moesin homology (FERM) domain of ezrin reversed the wt NHERF1 overexpression-induced increase in both F-actin and CFTR-dependent chloride secretion. wt NHERF1 overexpression enhanced the interaction between NHERF1 and both CFTR and ezrin and between ezrin and actin and the overexpression of wt NHERF1, but not NHERF1-Delta ERM, also increased the phosphorylation of ezrin in the apical region of the cell monolayers. Furthermore, wt NHERF1 increased RhoA activity and transfection of constitutively active RhoA in CFBE41o-cells was sufficient to redistribute phospho-ezrin to the membrane fraction and rescue both the F-actin content and the CFTR-dependent chloride efflux. Rho kinase (ROCK) inhibition, in contrast, reversed the wt NHERF1 overexpression-induced increase of membrane phospho-ezrin, F-actin content, and CFTR-dependent secretion. We conclude that NHERF1 overexpression in CFBE41o-rescues CFTR-dependent chloride secretion by forming the multiprotein complex RhoA-ROCK-ezrin-actin that, via actin cytoskeleton reorganization, tethers F508del CFTR to the cytoskeleton stabilizing it on the apical membrane.


Tutti gli autori

  • FAVIA M.;RESHKIN S.J.;CASAVOLA V.

Titolo volume/Rivista

Non Disponibile


Anno di pubblicazione

2010

ISSN

1059-1524

ISBN

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Numero di citazioni Wos

61

Ultimo Aggiornamento Citazioni

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Numero di citazioni Scopus

56

Ultimo Aggiornamento Citazioni

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Settori ERC

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Codici ASJC

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