Rescue of vasopressin V2 receptor mutants by chemical chaperones: specificity and mechanism

Because missense mutations in genetic diseases of membrane proteins often result in endoplasmic reticulum (ER) retention of functional proteins, drug-induced rescue of their cell surface expression and understanding the underlying mechanism are of clinical value. To study this, we tested chemical ch...

Full description

Saved in:
Bibliographic Details
Published in:Molecular biology of the cell 2006-01, Vol.17 (1), p.379-386
Main Authors: Robben, J H, Sze, M, Knoers, N V A M, Deen, P M T
Format: Article
Language:English
Subjects:
Animals
Biological Transport
Calcium - metabolism
Cell Line
Cell Membrane - metabolism
Cell Membrane Permeability
Curcumin - pharmacology
Cytosol - metabolism
Dogs
Endoplasmic Reticulum - metabolism
Humans
Ionomycin - pharmacology
Ligands
Molecular Chaperones - metabolism
Mutation - genetics
Receptors, Vasopressin - genetics
Receptors, Vasopressin - metabolism
Sensitivity and Specificity
Thapsigargin - pharmacology
Valine - genetics
Valine - metabolism
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Because missense mutations in genetic diseases of membrane proteins often result in endoplasmic reticulum (ER) retention of functional proteins, drug-induced rescue of their cell surface expression and understanding the underlying mechanism are of clinical value. To study this, we tested chemical chaperones and sarco(endo)plasmic reticulum Ca2+ ATPase pump inhibitors on Madin-Darby canine kidney cells expressing nine ER-retained vasopressin type-2 receptor (V2R) mutants involved in nephrogenic diabetes insipidus. Of these nine, only V2R-V206D showed improved maturation and plasma membrane rescue with glycerol, dimethyl sulfoxide (DMSO), thapsigargin/curcumin, and ionomycin but not with other osmolytes or growth at 27 degrees C. This revealed that rescue is mutant specific and that this mutant is prone to rescue by multiple compounds. Rescue did not involve changed expression of molecular chaperones calnexin, heat-shock protein (HSP) 70, or HSP90. V2R antagonist SR121463B treatment revealed that V2R-V206D and V2R-S167T were rescued and matured to a greater extent, suggesting that the rescuing activity of a pharmacological versus chemical chaperone is broader and stronger. Calcium measurements showed that rescue of V2R-V206D by thapsigargin, curcumin, and ionomycin was because of increased cytosolic calcium level, rather than decreased endoplasmic reticulum calcium level. The molecular mechanism underlying rescue by DMSO, glycerol, and SR121463B is different, because with these compounds intracellular calcium levels were unaffected.
ISSN:1059-1524
1939-4586
DOI:10.1091/mbc.E05-06-0579