title: Restriction enzymes permit quantitative determination of defined chromatin structures within the chromosome.
abstract: Open chromatin structures, operationally defined as nuclease-hypersensitive sites, are frequently found spanning the controlling regions of genes and they may ensure that trans-acting factors have ready access to their genomic substrates. The rapidity and extent of induction of a gene may be dependent on the probability that its promoter is folded into an open structure. We show that restriction enzymes can be used to estimate the probability that a given promoter region is contained within a defined structure in the chromosome. In the case of the Drosophila major heat-shock-protein gene, we show that an individual promoter element is folded in an accessible form in at least 75% of embryonic chromosomes. This efficient maintenance of the hypersensitive region may be a necessary precondition for a rapid heat-shock response.
authors.affiliation: Institut für Genetik, Universität zu Köln, Federal Republic of Germany.
authors.forename: R S
authors.initials: RS
authors.lastname: Jack
authors.forename: P
authors.initials: P
authors.lastname: Moritz
authors.forename: S
authors.initials: S
authors.lastname: Cremer
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D002843:Chromatin / Q000378:metabolism; D002875:Chromosomes / Q000378:metabolism; D004247:DNA / Q000235:genetics; D004262:DNA Restriction Enzymes / Q000378:metabolism*; D004330:Drosophila / Q000235:genetics; D006360:Heat-Shock Proteins / Q000235:genetics; D011401:Promoter Regions, Genetic; D014170:Transformation, Genetic
chemical_list: D002843:Chromatin; D006360:Heat-Shock Proteins; D004247:DNA; D004262:DNA Restriction Enzymes