title: Drosophila polytene chromosome bands formed by gene introns.
abstract: Genetic organization of bands and interbands in polytene chromosomes has long remained a puzzle for geneticists. It has been recently demonstrated that interbands typically correspond to the 5'-ends of house-keeping genes, whereas adjacent loose bands tend to be composed of coding sequences of the genes. In the present work, we made one important step further and mapped two large introns of ubiquitously active genes on the polytene chromosome map. We show that alternative promoter regions of these genes map to interbands, whereas introns and coding sequences found between those promoters correspond to loose grey bands. Thus, a gene having its long intron "sandwiched" between to alternative promoters and a common coding sequence may occupy two interbands and one band in the context of polytene chromosomes. Loose, partially decompacted bands appear to host large introns.
authors.affiliation: Institute of Molecular and Cellular Biology, SB RAS, Novosibirsk, 630090, Russia.|Novosibirsk State University, Novosibirsk, 630090, Russia.
authors.forename: I F
authors.initials: IF
authors.lastname: Zhimulev
authors.affiliation: Institute of Molecular and Cellular Biology, SB RAS, Novosibirsk, 630090, Russia.
authors.forename: L V
authors.initials: LV
authors.lastname: Boldyreva
authors.affiliation: Institute of Molecular and Cellular Biology, SB RAS, Novosibirsk, 630090, Russia.
authors.forename: O V
authors.initials: OV
authors.lastname: Demakova
authors.affiliation: Institute of Molecular and Cellular Biology, SB RAS, Novosibirsk, 630090, Russia.
authors.forename: G V
authors.initials: GV
authors.lastname: Poholkova
authors.affiliation: Institute of Molecular and Cellular Biology, SB RAS, Novosibirsk, 630090, Russia.
authors.forename: V A
authors.initials: VA
authors.lastname: Khoroshko
authors.affiliation: Institute of Molecular and Cellular Biology, SB RAS, Novosibirsk, 630090, Russia.
authors.forename: T Yu
authors.initials: TY
authors.lastname: Zykova
authors.affiliation: Institute of Molecular Genetics RAS, Moscow, 123182, Russia. zhimulev@mcb.nsc.ru.
authors.forename: S A
authors.initials: SA
authors.lastname: Lavrov
authors.affiliation: Institute of Molecular and Cellular Biology, SB RAS, Novosibirsk, 630090, Russia.
authors.forename: E S
authors.initials: ES
authors.lastname: Belyaeva
mesh_terms: D000818:Animals; D004330:Drosophila / Q000235:genetics*; D017344:Genes, Insect; D007438:Introns; D020161:Physical Chromosome Mapping; D059007:Polytene Chromosomes / Q000235:genetics*