Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
45
pubmed:dateCreated
2004-11-11
pubmed:abstractText
Machado-Joseph disease (MJD) is an inherited neurodegenerative disorder caused by ataxin-3 with a polyglutamine expansion. It is proposed that a toxic cleavage fragment of mutant ataxin-3 alternatively spliced isoform mjd1a triggers neurodegeneration, although this fragment has not yet been detected in the brains of MJD patients or in animal models. We have now generated transgenic mice expressing human mutant (Q71) or normal (Q20) ataxin-3 mjd1a under the control of the mouse prion promoter. Q71 transgenic mice expressing mutant ataxin-3 mjd1a above a critical level developed a phenotype similar to MJD including progressive postural instability, gait and limb ataxia, weight loss, premature death, neuronal intranuclear inclusions, and decreased tyrosine hydroxylase-positive neurons in the substantia nigra (determined by unbiased stereology). Q20 transgenic mice had normal behavior and pathology. Brains from sick Q71 transgenic mice contained an abundant mutant ataxin-3 mjd1a putative-cleavage fragment (Fragment), which was scarce in normal Q71 transgenic mice. Reactivity of the Fragment with a panel of antibodies and comigration with truncations of mutant ataxin-3 revealed that it contained residues C terminal to amino acid 221 to include the polyglutamine expansion. A similar portion of mutant ataxin-3 mjd1a expressed in transfected neuroblastoma cells was toxic above a critical concentration. The Fragment was more abundant in two affected brain regions of MJD patients. Thus, we have developed a murine model for mutant ataxin-3 mjd1a toxicity and identified a putative-cleavage fragment of the disease protein in the brains of these transgenic mice and MJD patients that is cytotoxic above a critical concentration.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1529-2401
pubmed:author
pubmed:issnType
Electronic
pubmed:day
10
pubmed:volume
24
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
10266-79
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:15537899-Adult, pubmed-meshheading:15537899-Alternative Splicing, pubmed-meshheading:15537899-Amino Acid Sequence, pubmed-meshheading:15537899-Animals, pubmed-meshheading:15537899-Brain Chemistry, pubmed-meshheading:15537899-Cell Line, Tumor, pubmed-meshheading:15537899-Dose-Response Relationship, Drug, pubmed-meshheading:15537899-Exploratory Behavior, pubmed-meshheading:15537899-Female, pubmed-meshheading:15537899-Hand Strength, pubmed-meshheading:15537899-Humans, pubmed-meshheading:15537899-Intranuclear Inclusion Bodies, pubmed-meshheading:15537899-Machado-Joseph Disease, pubmed-meshheading:15537899-Male, pubmed-meshheading:15537899-Mice, pubmed-meshheading:15537899-Mice, Transgenic, pubmed-meshheading:15537899-Middle Aged, pubmed-meshheading:15537899-Minisatellite Repeats, pubmed-meshheading:15537899-Molecular Sequence Data, pubmed-meshheading:15537899-Nerve Tissue Proteins, pubmed-meshheading:15537899-Neuroblastoma, pubmed-meshheading:15537899-Neurons, pubmed-meshheading:15537899-Nuclear Proteins, pubmed-meshheading:15537899-Peptide Fragments, pubmed-meshheading:15537899-Phenotype, pubmed-meshheading:15537899-Postural Balance, pubmed-meshheading:15537899-Reflex, pubmed-meshheading:15537899-Repressor Proteins, pubmed-meshheading:15537899-Subcellular Fractions, pubmed-meshheading:15537899-Substantia Nigra, pubmed-meshheading:15537899-Transcription Factors, pubmed-meshheading:15537899-Transfection
pubmed:year
2004
pubmed:articleTitle
A mutant ataxin-3 putative-cleavage fragment in brains of Machado-Joseph disease patients and transgenic mice is cytotoxic above a critical concentration.
pubmed:affiliation
Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural