title: The Drosophila TGF alpha homolog Spitz acts in photoreceptor recruitment in the developing retina.
abstract: In vertebrates and Drosophila, the Epidermal Growth Factor Receptor (EGFR) signal transduction pathway is important in the regulation of cellular development. EGFR is bound by several activating ligands including Transforming Growth Factor-alpha in vertebrates, and its homolog Spitz in Drosophila. It has been shown that Spitz and EGFR act in the development of the Drosophila central nervous system and compound eye. Here we show that spitz function is required in developing ommatidia for the first cell recruitment step, and that Spitz pro-protein is expressed in the retinal neurons as they begin to differentiate. We propose a 'two-key' model for additive signal transduction from EGFR and other receptor tyrosine kinases, via the Ras pathway, in the developing eye.
authors.affiliation: Department of Biological Sciences, University of Southern California, Los Angeles 90089-1340, USA.
authors.forename: M
authors.initials: M
authors.lastname: Tio
authors.forename: K
authors.initials: K
authors.lastname: Moses
mesh_terms: D000818:Animals; D001921:Brain / Q000166:cytology / Q000196:embryology; D002454:Cell Differentiation; D002874:Chromosome Mapping; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000196:embryology* / Q000235:genetics*; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000502:physiology; D004815:Epidermal Growth Factor; D066246:ErbB Receptors / Q000502:physiology; D018507:Gene Expression Regulation, Developmental; D008565:Membrane Proteins / Q000096:biosynthesis / Q000502:physiology*; D009030:Mosaicism; D009474:Neurons / Q000166:cytology / Q000502:physiology; D017956:Photoreceptor Cells, Invertebrate / Q000196:embryology*; D012160:Retina / Q000196:embryology*; D015398:Signal Transduction; D016211:Transforming Growth Factor alpha / Q000502:physiology; D014714:Vertebrates
chemical_list: D029721:Drosophila Proteins; D008565:Membrane Proteins; D016211:Transforming Growth Factor alpha; C076026:spi protein, Drosophila; D004815:Epidermal Growth Factor; D066246:ErbB Receptors