Project description:ChIP-chip experiments with NimbleGen whole-genome tiling arrays to compare Su(Hw), dCTCF, BEAF, and CP190 localization on DNA in Kc and Mbn2 cells revealed that BEAF is a third subclass of CP190-containing insulators. The DNA binding proteins, Su(Hw), dCTCF, and BEAF show unique distribution patterns with respect to the location and expression level of genes, suggesting diverse roles for these three subclasses of insulators in genome organization. Notably, cell line specific localization sites for all three DNA binding proteins as well as CP190 indicate multiple levels at which insulators can be regulated to affect gene expression.

2009-05-15 | GSE15661 | GEO

Cooperation between architectural C2H2 proteins in CP190 recruitment to Drosophila regulatory elements [ChIP-Seq]

Project description:CTCF is the best-studied architectural protein that is highly conserved among animals, including Drosophila and mammals. In Drosophila, CTCF is involved in the organization of functional promoters and insulators, in cooperation with many other architectural proteins, including Su(Hw) and Pita. These proteins, like many other architectural proteins, interact with CP190, which, along with its partners, recruits transcriptional complexes to target promoters. This study was conducted to investigate the cooperation between architectural proteins in the recruitment of CP190 to regulatory elements. We generated transgenic flies expressing double and triple mutants of dCTCF, Su(Hw), and Pita that cannot interact with CP190. The single mutants are fully viable; however, few triple mutants develop into adults. In the triple mutant, although the CP190 concentration is reduced, the level of gene transcription remains unaltered, suggesting that co-expression of the three mutant proteins is responsible for CP190 instability. ChIP-seq analysis showed that CP190 is required for dCTCF–chromatin binding. In the triple mutant, CP190 demonstrates an almost complete loss of association with the promoters and insulators to which the tested architectural proteins bind; however, these regulatory elements were found to retain their activity. Architectural proteins cooperate to recruit CP190 to regulatory elements and determine its stability. Despite the important role of CP190 in transcriptional regulation, its functions may be partially performed by partner proteins.

2026-03-10 | GSE308016 | GEO

Gene expression analysis of Kc cells from Drosophila melanogaster during ecdysone treatment and CP190 knockdown

Project description:This study examines the changes in genes expression that occur in Drosophila melanogaster during the ecdysone response as well as during RNAi knockdown of the insulator protein, CP190. Analysis was performed in Kc cells after 0, 3, and 48 hours of ecdysone treatment in the presence of either control or CP190 knockdown.

2011-10-14 | GSE30686 | GEO

Drosophila melanogaster

Project description:Analysis of genome-wide binding of the insulator factors CTCF and CP190

| PRJNA114155 | ENA

Drosophila melanogaster

Project description:Gene expression analysis of Drosophila melanogaster S2 cells after RNAi-mediated depletion of the insulator factor CP190

| PRJNA114125 | ENA

Mechanism and functional role of the interaction between CP190 and the architectural protein Pita in Drosophila melanogaster

Project description:The architectural protein Pita is critical for Drosophila embryogenesis and predominantly binds to gene promoters and insulators. In particular, Pita is involved in the organization of boundaries between regulatory domains, controlled by the expression of three hox genes in the Bithorax complex (BX-C). The best-characterized partner for Pita is the BTB/POZ-domain containing protein CP190. Here, we precisely mapped two unstructured regions of Pita that interact with the BTB domain of CP190. The deletion of the CP190-interacting regions did not significantly affect the binding of the mutant Pita protein to most chromatin sites. The expression of the mutant protein completely complemented the null pita mutation. However, the mutant Pita protein does not support the ability of multimerized Pita sites to prevent cross-talk between the iab-6 and iab-7 regulatory domains that activate the expression of Abdominal-B (Abd-B), one of the genes in the BX-C. The recruitment of the Pita region and the interaction with CP190 and the polytene chromosomes of larvae induces the formation of a new interband, which is a consequence of the formation of open chromatin in this region. These results suggested that the interaction with CP190 is required for the primary Pita activities, but other architectural proteins may also recruit CP190 in flies expressing only the mutant Pita protein.

2020-11-30 | GSE160007 | GEO

Drosophila melanogaster

Project description:Next Generation Sequencing analysis of Functional Interactions among Insulator Proteins [CP190 ChIP-Seq]

| PRJNA230397 | ENA