Format

Send to

Choose Destination
J Biol Chem. 2010 Nov 12;285(46):35825-35. doi: 10.1074/jbc.M110.131623. Epub 2010 Jul 28.

The cystic fibrosis-causing mutation deltaF508 affects multiple steps in cystic fibrosis transmembrane conductance regulator biogenesis.

Author information

1
Department of Physiology, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA.

Abstract

The deletion of phenylalanine 508 in the first nucleotide binding domain of the cystic fibrosis transmembrane conductance regulator is directly associated with >90% of cystic fibrosis cases. This mutant protein fails to traffic out of the endoplasmic reticulum and is subsequently degraded by the proteasome. The effects of this mutation may be partially reversed by the application of exogenous osmolytes, expression at low temperature, and the introduction of second site suppressor mutations. However, the specific steps of folding and assembly of full-length cystic fibrosis transmembrane conductance regulator (CFTR) directly altered by the disease-causing mutation are unclear. To elucidate the effects of the ΔF508 mutation, on various steps in CFTR folding, a series of misfolding and suppressor mutations in the nucleotide binding and transmembrane domains were evaluated for effects on the folding and maturation of the protein. The results indicate that the isolated NBD1 responds to both the ΔF508 mutation and intradomain suppressors of this mutation. In addition, identification of a novel second site suppressor of the defect within the second transmembrane domain suggests that ΔF508 also effects interdomain interactions critical for later steps in the biosynthesis of CFTR.

PMID:
20667826
PMCID:
PMC2975206
DOI:
10.1074/jbc.M110.131623
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center