title: A minisatellite with fold-back structure is included in the 5'-flanking region of the Adh gene of Scaptodrosophila lebanonensis.
abstract: A tandem repetitive sequence with a repeat unit of 12 bp has been found 1.3 kb upstream of the Adh gene of Scaptodrosophila lebanonensis. This repetitive sequence extends over 4.3 kb and consists of two inverted arrays (a fold-back segment). The repeated unit with a consensus sequence GAATACAGAATA is highly conserved and the nucleotide substitutions are not distributed randomly among the 12 bp. In situ hybridization in S. lebanonensis polytene chromosomes revealed two signals, one at the 60A section, the Adh locus, and a second site in the same chromosome at the 60C section close to the telomere. This same pattern of hybridization is obtained in all the analyzed strains including the subspecies S. lebanonensis casteeli. The minisatellite sequence accounts for about 0.03-0.04% of the S. lebanonensis genome and showed intraspecific variability in tandem repeat numbers. Possible functions of this sequence are discussed.
authors.affiliation: Departament de Genètica, Facultat de Biologia, Universitat de Barcelona, Avda. Diagonal 645, 08028 Barcelona, Spain. dorcas@porthos.bio.ub.es
authors.forename: D J
authors.initials: DJ
authors.lastname: Orengo
authors.forename: M
authors.initials: M
authors.lastname: Papaceit
authors.forename: E
authors.initials: E
authors.lastname: Juan
mesh_terms: D024506:5' Flanking Region / Q000235:genetics*; D000426:Alcohol Dehydrogenase / Q000235:genetics*; D000818:Animals; D001483:Base Sequence; D004247:DNA / Q000737:chemistry / Q000235:genetics; D018428:Drosophilidae / Q000201:enzymology / Q000235:genetics*; D017344:Genes, Insect / Q000235:genetics*; D017403:In Situ Hybridization; D018598:Minisatellite Repeats / Q000235:genetics*; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
chemical_list: D004247:DNA; D000426:Alcohol Dehydrogenase