Linked Life Data

17381543

Source:http://linkedlifedata.com/resource/pubmed/id/17381543

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2007-8-29
pubmed:abstractText
Cell differentiation is a multi-step process marked by progressive silencing of gene expression through mechanisms believed to involve heterochromatin. We have previously shown that interaction between the Krüppel associated box-containing zinc finger proteins (KRAB-ZFP) corepressor TIF1beta and the heterochromatin proteins HP1 is essential for progression through differentiation of embryonal carcinoma F9 cells. This analysis clearly demonstrated the link between gene specific repressors, components of heterochromatin and cell differentiation. In mammals, there are three HP1 isotypes, HP1alpha, beta, and gamma, that appear to be involved in both eu- and heterochromatin, but whose individual functions are still poorly defined. Therefore, the aim of the present study was to determine in vivo (i) which HP1 isotypes interact with TIF1beta, (ii) in which sub-nuclear compartments these interactions occur and (iii) whether these interactions are regulated during cell differentiation. To address these questions, we established stable F9 cell lines co-expressing TIF1beta fused to the ECFP fluorophore and HP1alpha, beta, or gamma fused to the EYFP fluorophore. Using the Föster resonance energy transfer (FRET) technology, we map the physical interaction between TIF1beta-CFP and the different HP1-YFP isotypes in living F9 cells. We demonstrate that in non-differentiated cells, TIF1beta-CFP/HP1-YFP interaction occurs only within euchromatin and involves selectively HP1beta-YFP and HP1gamma-YFP, but not HP1alpha-YFP. Furthermore, in differentiated cells, TIF1beta-CFP selectively associates with HP1beta-YFP within heterochromatin, while TIF1beta-CFP/HP1gamma-YFP is exclusively present within euchromatin. No physical TIF1beta-CFP/HP1alpha-YFP interaction is detected in neither non differentiated nor differentiated cells. These results support the notion that, in vivo, HP1 isotypes have specific nonredundant functions and provide evidence for HP1beta playing an essential role in the shuttling of TIF1beta from eu- to heterochromatin during cell differentiation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Chromosomal Proteins, Non-Histone, http://linkedlifedata.com/resource/pubmed/chemical/Cyan Fluorescent Protein, http://linkedlifedata.com/resource/pubmed/chemical/Euchromatin, http://linkedlifedata.com/resource/pubmed/chemical/Green Fluorescent Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Heterochromatin, http://linkedlifedata.com/resource/pubmed/chemical/Luminescent Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Nuclear Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Protein Isoforms, http://linkedlifedata.com/resource/pubmed/chemical/Repressor Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Transcription Factors, http://linkedlifedata.com/resource/pubmed/chemical/Trim28 protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/heterochromatin-specific...
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0301-4681
pubmed:author
pubmed:issnType
Print
pubmed:volume
75
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
627-37
pubmed:dateRevised
2011-4-28
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Dynamic and selective interactions of the transcriptional corepressor TIF1 beta with the heterochromatin protein HP1 isotypes during cell differentiation.
pubmed:affiliation
Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP/Collège de France, BP10142, 67404 Illkirch-Cedex, France. florence.cammas@igbmc.u-strasbg.fr
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't