title: Involvement of winged eye encoding a chromatin-associated bromo-adjacent homology domain protein in disc specification.
abstract: How organ identity is determined is a fundamental question in developmental biology. In Drosophila, field-specific selector genes, such as eyeless (ey) for eyes and vestigial (vg) for wings, participate in the determination of imaginal disc-specific identity. We performed gain-of-function screening and identified a gene named winged eye (wge), which encodes a bromo-adjacent homology domain protein that localizes at specific sites on chromosomes in a bromo-adjacent homology domain-dependent manner. Overexpression of wge-induced ectopic wings with antero-posterior and dorso-ventral axes in the eye field in a region-specific Hox gene-(Antennapedia) independent manner. Overexpression of wge was sufficient for ectopic expression of vg in eye discs. A context-dependent requirement of wge was demonstrated for vg expression in wing discs and for expression of eyes absent (eya), a control gene for eye development downstream of ey, in eye discs. In contrast to vg, however, overexpression of wge inhibited EY-mediated expression of eya. Consistent with colocalization on polytene chromosomes of WGE and Posterior sex combs (PSC), a Polycomb group gene product, we demonstrated an antagonistic genetic interaction between wge and Psc. These findings suggest that wge functions in the determination of disc-specific identity, downstream of Hox genes.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai 980-8578, Japan.
authors.forename: Tomonori
authors.initials: T
authors.lastname: Katsuyama
authors.forename: Tomo
authors.initials: T
authors.lastname: Sugawara
authors.forename: Masanobu
authors.initials: M
authors.lastname: Tatsumi
authors.forename: Yoshiteru
authors.initials: Y
authors.lastname: Oshima
authors.forename: Walter J
authors.initials: WJ
authors.lastname: Gehring
authors.forename: Toshiro
authors.initials: T
authors.lastname: Aigaki
authors.forename: Shoichiro
authors.initials: S
authors.lastname: Kurata
mesh_terms: D000818:Animals; D001483:Base Sequence; D002843:Chromatin / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics; D004330:Drosophila / Q000235:genetics* / Q000254:growth & development; D029721:Drosophila Proteins / Q000235:genetics*; D005123:Eye / Q000254:growth & development; D051858:Forkhead Transcription Factors / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental; D008969:Molecular Sequence Data; D009024:Morphogenesis / Q000235:genetics; D009928:Organ Specificity / Q000235:genetics*; D014921:Wings, Animal / Q000254:growth & development
chemical_list: D002843:Chromatin; D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D051858:Forkhead Transcription Factors; C506268:wge protein, Drosophila