Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2008-2-14
pubmed:abstractText
Friedreich ataxia (FRDA) is caused by a homozygous GAA repeat expansion mutation within intron 1 of the FXN gene, leading to reduced expression of frataxin protein. Evidence suggests that the mutation may induce epigenetic changes and heterochromatin formation, thereby impeding gene transcription. In particular, studies using FRDA patient blood and lymphoblastoid cell lines have detected increased DNA methylation of specific CpG sites upstream of the GAA repeat and histone modifications in regions flanking the GAA repeat. In this report we show that such epigenetic changes are also present in FRDA patient brain, cerebellum and heart tissues, the primary affected systems of the disorder. Bisulfite sequence analysis of the FXN flanking GAA regions reveals a shift in the FRDA DNA methylation profile, with upstream CpG sites becoming consistently hypermethylated and downstream CpG sites becoming consistently hypomethylated. We also identify differential DNA methylation at three specific CpG sites within the FXN promoter and one CpG site within exon 1. Furthermore, we show by chromatin immunoprecipitation analysis that there is overall decreased histone H3K9 acetylation together with increased H3K9 methylation of FRDA brain tissue. Further studies of brain, cerebellum and heart tissues from our GAA repeat expansion-containing FRDA YAC transgenic mice reveal comparable epigenetic changes to those detected in FRDA patient tissue. We have thus developed a mouse model that will be a valuable resource for future therapeutic studies targeting epigenetic modifications of the FXN gene to increase frataxin expression.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1460-2083
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
735-46
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:18045775-Acetylation, pubmed-meshheading:18045775-Animals, pubmed-meshheading:18045775-Brain, pubmed-meshheading:18045775-Case-Control Studies, pubmed-meshheading:18045775-Cerebellum, pubmed-meshheading:18045775-Chromatin Immunoprecipitation, pubmed-meshheading:18045775-CpG Islands, pubmed-meshheading:18045775-DNA Methylation, pubmed-meshheading:18045775-Epigenesis, Genetic, pubmed-meshheading:18045775-Friedreich Ataxia, pubmed-meshheading:18045775-Gene Expression Profiling, pubmed-meshheading:18045775-Gene Silencing, pubmed-meshheading:18045775-Genes, Recessive, pubmed-meshheading:18045775-Histones, pubmed-meshheading:18045775-Homozygote, pubmed-meshheading:18045775-Humans, pubmed-meshheading:18045775-Mice, pubmed-meshheading:18045775-Mice, Transgenic, pubmed-meshheading:18045775-Mutation, pubmed-meshheading:18045775-Myocardium, pubmed-meshheading:18045775-Promoter Regions, Genetic, pubmed-meshheading:18045775-RNA, Messenger, pubmed-meshheading:18045775-Trinucleotide Repeat Expansion
pubmed:year
2008
pubmed:articleTitle
The Friedreich ataxia GAA repeat expansion mutation induces comparable epigenetic changes in human and transgenic mouse brain and heart tissues.
pubmed:affiliation
Hereditary Ataxia Group, Centre for Cell & Chromosome Biology and Brunel Institute of Cancer Genetics & Pharmacogenomics, Division of Biosciences, School of Health Sciences & Social Care, Brunel University, Uxbridge UB8 3PH, UK.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't