Mechanisms of chaperone suppression of polyglutamine disease: selectivity, synergy and modulation of protein solubility in Drosophila.
At least eight dominant human neurodegenerative diseases are due to the expansion of a polyglutamine within the disease proteins. This confers toxicity on the proteins and is associated with nuclear inclusion formation. Recent findings indicate that molecular chaperones can modulate polyglutamine pathogenesis, but the basis of polyglutamine toxicity and the mechanism by which chaperones suppress neurodegeneration remains unknown. In a Drosophila: disease model, we demonstrate that chaperones show substrate specificity for polyglutamine protein, as well as synergy in suppression of neurotoxicity. Our analysis also reveals that chaperones alter the solubility properties of the protein, indicating that chaperone modulation of neurodegeneration in vivo is associated with altered biochemical properties of the mutant polyglutamine protein. These findings have implications for these and other human neurodegenerative diseases associated with abnormal protein aggregation.
Chan
H Y
HY
Department of Biology, Howard Hughes Medical Institute, 415 South University Avenue, University of Pennsylvania, Philadelphia, PA 19104-6018, USA.
Warrick
J M
JM
Gray-Board
G L
GL
Paulson
H L
HL
Bonini
N M
NM
D000818:Animals; D004195:Disease Models, Animal; D004331:Drosophila melanogaster / Q000235:genetics / Q000378:metabolism; D005838:Genotype; D050956:HSP40 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020271:Heredodegenerative Disorders, Nervous System / Q000235:genetics / Q000378:metabolism*; D006651:Histocytochemistry; D006801:Humans; D000071058:Huntingtin Protein; D019476:Insect Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D018832:Molecular Chaperones / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D009687:Nuclear Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D010455:Peptides / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D012160:Retina / Q000378:metabolism / Q000473:pathology; D012995:Solubility; D013379:Substrate Specificity; D019680:Trinucleotide Repeat Expansion / Q000235:genetics*
D050956:HSP40 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; C086055:HTT protein, human; D006360:Heat-Shock Proteins; D000071058:Huntingtin Protein; D019476:Insect Proteins; D018832:Molecular Chaperones; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D010455:Peptides; C097188:polyglutamine