title: [Contribution of the SuUR gene to the organization of epigenetically repressed regions of Drosophila melanogaster chromosomes].
abstract: A significant portion of a eukaryotic genome is silent (epigenetically repressed). In Drosophila melanogaster, this portion includes mainly regions of pericentric and intercalary heterochromatin and euchromatin regions subject to position-effect variegation. Detailed study of the organization of intercalary heterochromatin regions of Drosophila melanogaster polytene chromosomes started from the discovery of the SuUR gene (Suppressor of UnderReplication). The ability of the SuUR mutation to suppress underreplication in intercalary heterochromatin regions was used for molecular tagging of these regions. We showed that underreplicated intercalary heterochromatin regions contained silent unique genes and retained the features of late replication and transcriptionally inactive chromatin state in various cell types. Over 50% of these regions contain unique genes clustered on the base of coordinated expression. The origin of clusters and putative mechanisms of their gene expression are discussed. Data on the SuUR gene, its expression, and effect on polytene chromosome structure and replication are summarized.
authors.forename: T D
authors.initials: TD
authors.lastname: Kolesnikova
authors.forename: E N
authors.initials: EN
authors.lastname: Andreeva
authors.forename: A V
authors.initials: AV
authors.lastname: Pindiurin
authors.forename: N G
authors.initials: NG
authors.lastname: Anan'ko
authors.forename: S N
authors.initials: SN
authors.lastname: Beliakin
authors.forename: V V
authors.initials: VV
authors.lastname: Shloma
authors.forename: A A
authors.initials: AA
authors.lastname: Iurlova
authors.forename: I V
authors.initials: IV
authors.lastname: Makunin
authors.forename: G V
authors.initials: GV
authors.lastname: Pokholkova
authors.forename: E I
authors.initials: EI
authors.lastname: Volkova
authors.forename: E A
authors.initials: EA
authors.lastname: Zarutskaia
authors.forename: E B
authors.initials: EB
authors.lastname: Kokoza
authors.forename: V F
authors.initials: VF
authors.lastname: Seneshin
authors.forename: E S
authors.initials: ES
authors.lastname: Beliaeva
authors.forename: I F
authors.initials: IF
authors.lastname: Zhimulev
mesh_terms: D000818:Animals; D002875:Chromosomes; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D029721:Drosophila Proteins / Q000235:genetics / Q000502:physiology*; D004331:Drosophila melanogaster / Q000235:genetics*; D044127:Epigenesis, Genetic; D023061:Gene Order; D017344:Genes, Insect / Q000235:genetics
chemical_list: D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; C464850:SuUR protein, Drosophila