Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
2000-11-28
pubmed:abstractText
Chromosomal abnormalities associated with hypomethylation of classical satellite regions are characteristic for the ICF immunodeficiency syndrome. We, as well as others, have found that these effects derive from mutations in the DNMT3B DNA methyltransferase gene. Here we examine further the molecular phenotype of ICF cells and report several examples of extensive hypomethylation that are associated with advanced replication time, nuclease hypersensitivity and a variable escape from silencing for genes on the inactive X and Y chromosomes. Our analysis suggests that all genes on the inactive X chromosome may be extremely hypomethylated at their 5' CpG islands. Our studies of G6PD in one ICF female and SYBL1 in another ICF female provide the first examples of abnormal escape from X chromosome inactivation in untransformed human fibroblasts. XIST RNA localization is normal in these cells, arguing against an independent silencing role for this RNA in somatic cells. SYBL1 silencing is also disrupted on the Y chromosome in ICF male cells. Increased chromatin sensitivity to nuclease was found at all hypomethylated promoters examined, including those of silenced genes. The persistence of inactivation in these latter cases appears to depend critically on delayed replication of DNA because escape from silencing was only seen when replication was advanced to an active X-like pattern.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0964-6906
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
9
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2575-87
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed-meshheading:11063717-Alleles, pubmed-meshheading:11063717-Cells, Cultured, pubmed-meshheading:11063717-Chromatin, pubmed-meshheading:11063717-CpG Islands, pubmed-meshheading:11063717-DNA, Satellite, pubmed-meshheading:11063717-DNA Methylation, pubmed-meshheading:11063717-DNA Replication, pubmed-meshheading:11063717-Dosage Compensation, Genetic, pubmed-meshheading:11063717-Female, pubmed-meshheading:11063717-Fibroblasts, pubmed-meshheading:11063717-Gene Silencing, pubmed-meshheading:11063717-Genetic Linkage, pubmed-meshheading:11063717-Glucosephosphate Dehydrogenase, pubmed-meshheading:11063717-Humans, pubmed-meshheading:11063717-Immunologic Deficiency Syndromes, pubmed-meshheading:11063717-Male, pubmed-meshheading:11063717-Membrane Proteins, pubmed-meshheading:11063717-Nuclease Protection Assays, pubmed-meshheading:11063717-Phenotype, pubmed-meshheading:11063717-Phosphoglycerate Kinase, pubmed-meshheading:11063717-Promoter Regions, Genetic, pubmed-meshheading:11063717-R-SNARE Proteins, pubmed-meshheading:11063717-RNA, Messenger, pubmed-meshheading:11063717-RNA, Untranslated, pubmed-meshheading:11063717-Time Factors, pubmed-meshheading:11063717-Transcription Factors, pubmed-meshheading:11063717-X Chromosome, pubmed-meshheading:11063717-Y Chromosome
pubmed:year
2000
pubmed:articleTitle
Escape from gene silencing in ICF syndrome: evidence for advanced replication time as a major determinant.
pubmed:affiliation
Department of Medicine, Box 357360, University of Washington, Seattle, WA 98195, USA. supreme@u.washington.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't