title: Dissection of open chromatin domain formation by site-specific recombination in Drosophila.
abstract: Drosophila polytene interphase chromosomes provide an ideal test system to study the rules that define the structure of chromatin domains. We established a transgenic condensed chromatin domain cassette for the insertion of large pieces of DNA by site-specific recombination. Insertion of this cassette into open chromatin generated a condensed domain, visible as an extra band on polytene chromosomes. Site-specific recombination of DNA sequence variants into this ectopic band allowed us to compare their capacity for open chromatin formation by cytogenetic methods. We demonstrate that the 61C7-8 interband DNA maintains its open chromatin conformation and epigenetic state at an ectopic position. By deletion analysis, we mapped the sequences essential for open chromatin formation to a 490-bp fragment in the proximal part of the 17-kb interband sequence. This fragment overlaps binding sites for the chromatin protein Chriz (also known as Chro), the histone kinase Jil-1 and the boundary element protein CP190. It also overlaps a promoter region that locates between the Rev1 and Med30 transcription units.
authors.affiliation: Humboldt University Berlin Institute of Biology, Cytogenetics Group, Chausseestrasse 117, 10115, Berlin, Germany thomas.zielke@gmx.de harald.saumweber@cms.hu-berlin.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Zielke
authors.affiliation: Humboldt University Berlin Institute of Biology, Cytogenetics Group, Chausseestrasse 117, 10115, Berlin, Germany thomas.zielke@gmx.de harald.saumweber@cms.hu-berlin.de.
authors.forename: Harald
authors.initials: H
authors.lastname: Saumweber
mesh_terms: D000818:Animals; D002843:Chromatin / Q000235:genetics* / Q000378:metabolism*; D059006:Chromosomes, Insect; D004247:DNA / Q000235:genetics / Q000378:metabolism; D004330:Drosophila / Q000235:genetics* / Q000378:metabolism*; D006657:Histones / Q000378:metabolism; D011995:Recombination, Genetic
chemical_list: D002843:Chromatin; D006657:Histones; D004247:DNA
keywords: CP190; Chriz; Interphase chromatin domain; Jil-1; Polytene chromosome