title: The transcription factor Glass links eye field specification with photoreceptor differentiation in Drosophila.
abstract: Eye development requires an evolutionarily conserved group of transcription factors, termed the retinal determination network (RDN). However, little is known about the molecular mechanism by which the RDN instructs cells to differentiate into photoreceptors. We show that photoreceptor cell identity in Drosophila is critically regulated by the transcription factor Glass, which is primarily expressed in photoreceptors and whose role in this process was previously unknown. Glass is both required and sufficient for the expression of phototransduction proteins. Our results demonstrate that the RDN member Sine oculis directly activates glass expression, and that Glass activates the expression of the transcription factors Hazy and Otd. We identified hazy as a direct target of Glass. Induced expression of Hazy in the retina partially rescues the glass mutant phenotype. Together, our results provide a transcriptional link between eye field specification and photoreceptor differentiation in Drosophila, placing Glass at a central position in this developmental process.
authors.affiliation: Department of Biology, University of Fribourg, Fribourg 1700, Switzerland.
authors.forename: F Javier
authors.initials: FJ
authors.lastname: Bernardo-Garcia
authors.affiliation: Department of Biology, University of Fribourg, Fribourg 1700, Switzerland.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Fritsch
authors.affiliation: Department of Biology, University of Fribourg, Fribourg 1700, Switzerland simon.sprecher@unifr.ch.
authors.forename: Simon G
authors.initials: SG
authors.lastname: Sprecher
mesh_terms: D000818:Animals; D004268:DNA-Binding Proteins / Q000502:physiology*; D004330:Drosophila; D029721:Drosophila Proteins / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000502:physiology; D055495:Neurogenesis / Q000502:physiology*; D017956:Photoreceptor Cells, Invertebrate / Q000166:cytology*; D012160:Retina / Q000166:cytology / Q000196:embryology
chemical_list: D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D018398:Homeodomain Proteins; C411858:Pph13 protein, Drosophila; C087289:gl protein, Drosophila; C093053:oc protein, Drosophila
keywords: Cell fate; Drosophila; Eye formation; Photoreceptor; Phototransduction