Inhibition of endoplasmic reticulum-associated degradation rescues native folding in loss of function protein misfolding diseases.

Abstract

Lysosomal storage disorders are often caused by mutations that destabilize native folding and impair trafficking of secretory proteins. We demonstrate that endoplasmic reticulum (ER)-associated degradation (ERAD) prevents native folding of mutated lysosomal enzymes in patient-derived fibroblasts from two clinically distinct lysosomal storage disorders, namely Gaucher and Tay-Sachs disease. Prolonging ER retention via ERAD inhibition enhanced folding, trafficking, and activity of these unstable enzyme variants. Furthermore, combining ERAD inhibition with enhancement of the cellular folding capacity via proteostasis modulation resulted in synergistic rescue of mutated enzymes. ERAD inhibition was achieved by cell treatment with small molecules that interfere with recognition (kifunensine) or retrotranslocation (eeyarestatin I) of misfolded substrates. These different mechanisms of ERAD inhibition were shown to enhance ER retention of mutated proteins but were associated with dramatically different levels of ER stress, unfolded protein response activation, and unfolded protein response-induced apoptosis.

• Authors: Fan Wang, Wensi Song, Giovanna Brancati, Laura Segatori
• Journal: The Journal of biological chemistry (J Biol Chem) Vol. 286 Issue 50 Pg. 43454-64 (Dec 16 2011) ISSN: 1083-351X [Electronic] United States
• PMID: 22006919 (Publication Type: Journal Article)

Chemical References

• 1-(4-chlorophenyl)-3-(3-(4-chlorophenyl)-5,5-dimethyl-1-(3-(5-nitrofuran-2-yl)allyldienehydrazinocarbonylmethyl)-2-oxoimidazolidin-4-yl)-1-hydroxyurea
• Alkaloids
• Hydrazones
• Molecular Chaperones
• kifunensine
• Hydroxyurea

Topics

• Alkaloids (pharmacology)
• Apoptosis (genetics, physiology)
• Blotting, Western
• Cells, Cultured
• Endoplasmic Reticulum-Associated Degradation (drug effects, genetics, physiology)
• Humans
• Hydrazones (pharmacology)
• Hydroxyurea (analogs & derivatives, pharmacology)
• Lysosomal Storage Diseases (genetics, metabolism)
• Molecular Chaperones (genetics, metabolism)
• Protein Folding (drug effects)
• Proteostasis Deficiencies (genetics, metabolism)
• Real-Time Polymerase Chain Reaction
• Unfolded Protein Response (drug effects, genetics, physiology)