Dorfin-CHIP chimeric proteins potently ubiquitylate and degrade familial ALS-related mutant SOD1 proteins and reduce their cellular toxicity

Shinsuke Ishigaki; Jun-ichi Niwa; Shin-ichi Yamada; Miho Takahashi; Takashi Ito; Jun Sone; Manabu Doyu; Fumihiko Urano; Gen Sobue

doi:10.1016/j.nbd.2006.09.017

Dorfin-CHIP chimeric proteins potently ubiquitylate and degrade familial ALS-related mutant SOD1 proteins and reduce their cellular toxicity

Neurobiol Dis. 2007 Feb;25(2):331-41. doi: 10.1016/j.nbd.2006.09.017. Epub 2006 Dec 6.

Authors

Shinsuke Ishigaki¹, Jun-ichi Niwa, Shin-ichi Yamada, Miho Takahashi, Takashi Ito, Jun Sone, Manabu Doyu, Fumihiko Urano, Gen Sobue

Affiliation

¹ Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya 466-8500, Japan.

PMID: 17157513
DOI: 10.1016/j.nbd.2006.09.017

Abstract

The ubiquitin-proteasome system (UPS) is involved in the pathogenetic mechanisms of neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS). Dorfin is a ubiquitin ligase (E3) that degrades mutant SOD1 proteins, which are responsible for familial ALS. Although Dorfin has potential as an anti-ALS molecule, its life in cells is short. To improve its stability and enhance its E3 activity, we developed chimeric proteins containing the substrate-binding hydrophobic portion of Dorfin and the U-box domain of the carboxyl terminus of Hsc70-interacting protein (CHIP), which has strong E3 activity through the U-box domain. All the Dorfin-CHIP chimeric proteins were more stable in cells than was wild-type Dorfin (Dorfin(WT)). One of the Dorfin-CHIP chimeric proteins, Dorfin-CHIP(L), ubiquitylated mutant SOD1 more effectively than did Dorfin(WT) and CHIP in vivo, and degraded mutant SOD1 protein more rapidly than Dorfin(WT) does. Furthermore, Dorfin-CHIP(L) rescued neuronal cells from mutant SOD1-associated toxicity and reduced the aggresome formation induced by mutant SOD1 more effectively than did Dorfin(WT).

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Amyotrophic Lateral Sclerosis / genetics
Amyotrophic Lateral Sclerosis / metabolism*
Animals
Cell Death / drug effects
Cell Death / physiology
Cell Line
DNA-Binding Proteins / genetics
DNA-Binding Proteins / metabolism*
DNA-Binding Proteins / pharmacology
Humans
Mice
Mutation / genetics
Nerve Degeneration / drug therapy
Nerve Degeneration / genetics
Nerve Degeneration / metabolism
Neurotoxins / antagonists & inhibitors
Neurotoxins / metabolism
Proteasome Endopeptidase Complex / drug effects
Proteasome Endopeptidase Complex / genetics
Proteasome Endopeptidase Complex / metabolism
Recombinant Fusion Proteins / genetics
Recombinant Fusion Proteins / metabolism*
Recombinant Fusion Proteins / pharmacology
Superoxide Dismutase / genetics
Superoxide Dismutase / metabolism*
Superoxide Dismutase / toxicity
Superoxide Dismutase-1
Ubiquitin / agonists
Ubiquitin / metabolism*
Ubiquitin-Protein Ligases / genetics
Ubiquitin-Protein Ligases / metabolism*
Ubiquitin-Protein Ligases / pharmacology

Substances

DNA-Binding Proteins
Neurotoxins
Recombinant Fusion Proteins
SOD1 protein, human
Ubiquitin
Sod1 protein, mouse
Superoxide Dismutase
Superoxide Dismutase-1
RNF19A protein, human
STUB1 protein, human
Ubiquitin-Protein Ligases
Proteasome Endopeptidase Complex