In:
Molecular Biology of the Cell, American Society for Cell Biology (ASCB), Vol. 18, No. 9 ( 2007-09), p. 3388-3397
Abstract:
Cystic fibrosis results from mutations in the cystic fibrosis conductance regulator protein (CFTR), a cAMP/protein kinase A (PKA) and ATP-regulated Cl − channel. CFTR is increasingly recognized as a component of multiprotein complexes and although several inhibitory proteins to CFTR have been identified, protein complexes that stimulate CFTR function remain less well characterized. We report that annexin 2 (anx 2)–S100A10 forms a functional cAMP/PKA/calcineurin (CaN)-dependent complex with CFTR. Cell stimulation with forskolin/3-isobutyl-1-methylxanthine significantly increases the amount of anx 2–S100A10 that reciprocally coimmunoprecipitates with cell surface CFTR and calyculin A. Preinhibition with PKA or CaN inhibitors attenuates the interaction. Furthermore, we find that the acetylated peptide (STVHEILCKLSLEG, Ac1-14), but not the nonacetylated equivalent N1-14, corresponding to the S100A10 binding site on anx 2, disrupts the anx 2–S100A10/CFTR complex. Analysis of 4,4′-diisothiocyanatostilbene-2,2′-disulfonic acid (DIDS) and CFTR inh172 -sensitive currents, taken as indication of the outwardly rectifying Cl − channels (ORCC) and CFTR-mediated currents, respectively, showed that Ac1-14, but not N1-14, inhibits both the cAMP/PKA-dependent ORCC and CFTR activities. CaN inhibitors (cypermethrin, cyclosporin A) discriminated between ORCC/CFTR by inhibiting the CFTR inh172 -, but not the DIDS-sensitive currents, by 〉 70%. Furthermore, peptide Ac1-14 inhibited acetylcholine-induced short-circuit current measured across a sheet of intact intestinal biopsy. Our data suggests that the anx 2–S100A10/CFTR complex is important for CFTR function across epithelia.
Type of Medium:
Online Resource
ISSN:
1059-1524
,
1939-4586
DOI:
10.1091/mbc.e07-02-0126
Language:
English
Publisher:
American Society for Cell Biology (ASCB)
Publication Date:
2007
detail.hit.zdb_id:
1474922-1
SSG:
12
