Loading...
A functional insulator screen identifies NURF and dREAM components to be required for enhancer-blocking.
Bohla, Dorte Herold, Martin Panzer, Imke Buxa, Melanie K Ali, Tamer Demmers, Jeroen Krüger, Marcus Scharfe, Maren Jarek, Michael Bartkuhn, Marek
Bohla, Dorte
Herold, Martin
Panzer, Imke
Buxa, Melanie K
Ali, Tamer
Demmers, Jeroen
Krüger, Marcus
Scharfe, Maren
Jarek, Michael
Bartkuhn, Marek
Files
Loading...
Open Access publication
Adobe PDF, 1.8 MB
Other Titles
Abstract
Chromatin insulators of higher eukaryotes functionally divide the genome into active and inactive domains. Furthermore, insulators regulate enhancer/promoter communication, which is evident from the Drosophila bithorax locus in which a multitude of regulatory elements control segment specific gene activity. Centrosomal protein 190 (CP190) is targeted to insulators by CTCF or other insulator DNA-binding factors. Chromatin analyses revealed that insulators are characterized by open and nucleosome depleted regions. Here, we wanted to identify chromatin modification and remodelling factors required for an enhancer blocking function. We used the well-studied Fab-8 insulator of the bithorax locus to apply a genome-wide RNAi screen for factors that contribute to the enhancer blocking function of CTCF and CP190. Among 78 genes required for optimal Fab-8 mediated enhancer blocking, all four components of the NURF complex as well as several subunits of the dREAM complex were most evident. Mass spectrometric analyses of CTCF or CP190 bound proteins as well as immune precipitation confirmed NURF and dREAM binding. Both co-localise with most CP190 binding sites in the genome and chromatin immune precipitation showed that CP190 recruits NURF and dREAM. Nucleosome occupancy and histone H3 binding analyses revealed that CP190 mediated NURF binding results in nucleosomal depletion at CP190 binding sites. Thus, we conclude that CP190 binding to CTCF or to other DNA binding insulator factors mediates recruitment of NURF and dREAM. Furthermore, the enhancer blocking function of insulators is associated with nucleosomal depletion and requires NURF and dREAM.
Citation
A functional insulator screen identifies NURF and dREAM components to be required for enhancer-blocking. 2014, 9 (9):e107765 PLoS ONE
Publisher
Journal
PubMed ID
PubMed Central ID
Additional Links
Embedded video
Type
Article
Language
en
Description
Series/Report no.
ISSN
1932-6203