CHIP suppresses polyglutamine aggregation and toxicity in vitro and in vivo.
Huntington's disease (HD) and other polyglutamine (polyQ) neurodegenerative diseases are characterized by neuronal accumulation of the disease protein, suggesting that the cellular ability to handle abnormal proteins is compromised. As both a cochaperone and ubiquitin ligase, the C-terminal Hsp70 (heat shock protein 70)-interacting protein (CHIP) links the two major arms of protein quality control, molecular chaperones, and the ubiquitin-proteasome system. Here, we demonstrate that CHIP suppresses polyQ aggregation and toxicity in transfected cell lines, primary neurons, and a novel zebrafish model of disease. Suppression by CHIP requires its cochaperone function, suggesting that CHIP acts to facilitate the solubility of mutant polyQ proteins through its interactions with chaperones. Conversely, HD transgenic mice that are haploinsufficient for CHIP display a markedly accelerated disease phenotype. We conclude that CHIP is a critical mediator of the neuronal response to misfolded polyQ protein and represents a potential therapeutic target in this important class of neurodegenerative diseases.
Miller
Victor M
VM
Department of Neurology, University of Iowa, Roy J. and Lucille A. Carver College of Medicine, Iowa City, Iowa 52242, USA.
Nelson
Rick F
RF
Gouvion
Cynthia M
CM
Williams
Aislinn
A
Rodriguez-Lebron
Edgardo
E
Harper
Scott Q
SQ
Davidson
Beverly L
BL
Rebagliati
Michael R
MR
Paulson
Henry L
HL
D000818:Animals; D015153:Blotting, Western / Q000379:methods; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology; D002522:Chlorocebus aethiops; D004195:Disease Models, Animal; D004622:Embryo, Mammalian; D004625:Embryo, Nonmammalian; D005455:Fluorescent Antibody Technique / Q000379:methods; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000378:metabolism; D006816:Huntington Disease / Q000188:drug therapy; D066298:In Vitro Techniques; D051379:Mice; D008822:Mice, Transgenic; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D009154:Mutation; D009433:Neural Inhibition / Q000187:drug effects*; D009474:Neurons / Q000166:cytology / Q000187:drug effects*; D010455:Peptides / Q000235:genetics / Q000378:metabolism*; D011863:Radioimmunoassay / Q000379:methods; D051381:Rats; D014162:Transfection / Q000379:methods; D044767:Ubiquitin-Protein Ligases / Q000494:pharmacology*; D015027:Zebrafish
D008869:Microtubule-Associated Proteins; C079240:Mtap2 protein, mouse; D010455:Peptides; D049452:Green Fluorescent Proteins; C097188:polyglutamine; C467728:STUB1 protein, human; D044767:Ubiquitin-Protein Ligases