title: Multiple regulatory safeguards confine the expression of the GATA factor Serpent to the hemocyte primordium within the Drosophila mesoderm.
abstract: serpent (srp) encodes a GATA-factor that controls various aspects of embryogenesis in Drosophila, such as fatbody development, gut differentiation and hematopoiesis. During hematopoiesis, srp expression is required in the embryonic head mesoderm and the larval lymph gland, the two known hematopoietic tissues of Drosophila, to obtain mature hemocytes. srp expression in the hemocyte primordium is known to depend on snail and buttonhead, but the regulatory complexity that defines the primordium has not been addressed yet. Here, we find that srp is sufficient to transform trunk mesoderm into hemocytes. We identify two disjoint cis-regulatory modules that direct the early expression in the hemocyte primordium and the late expression in mature hemocytes and lymph gland, respectively. During embryonic hematopoiesis, a combination of snail, buttonhead, empty spiracles and even-skipped confines the mesodermal srp expression to the head region. This restriction to the head mesoderm is crucial as ectopic srp in mesodermal precursors interferes with the development of mesodermal derivates and promotes hemocytes and fatbody development. Thus, several genes work in a combined fashion to restrain early srp expression to the head mesoderm in order to prevent expansion of the hemocyte primordium.
authors.affiliation: Interfakultäres Institut für Zellbiologie, Abteilung Genetik der Tiere, Fachbereich für Biologie, Universität Tübingen, Auf der Morgenstelle 28, Tübingen, Germany.
authors.forename: Philipp
authors.initials: P
authors.lastname: Spahn
authors.affiliation: Interfakultäres Institut für Zellbiologie, Abteilung Genetik der Tiere, Fachbereich für Biologie, Universität Tübingen, Auf der Morgenstelle 28, Tübingen, Germany; The Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge, United Kingdom.
authors.forename: Sven
authors.initials: S
authors.lastname: Huelsmann
authors.affiliation: Interfakultäres Institut für Zellbiologie, Abteilung Genetik der Tiere, Fachbereich für Biologie, Universität Tübingen, Auf der Morgenstelle 28, Tübingen, Germany; Institut für Genetik, Universität zu Köln, Weyertal 121, Köln, Germany.
authors.forename: Klaus-Peter
authors.initials: KP
authors.lastname: Rehorn
authors.affiliation: Interfakultäres Institut für Zellbiologie, Abteilung Genetik der Tiere, Fachbereich für Biologie, Universität Tübingen, Auf der Morgenstelle 28, Tübingen, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Mischke
authors.affiliation: Interfakultäres Institut für Zellbiologie, Abteilung Genetik der Tiere, Fachbereich für Biologie, Universität Tübingen, Auf der Morgenstelle 28, Tübingen, Germany.
authors.forename: Melanie
authors.initials: M
authors.lastname: Mayer
authors.affiliation: Institute for Research in Biomedicine, Baldiri Reixach 10-12, Barcelona, Spain.
authors.forename: Andreu
authors.initials: A
authors.lastname: Casali
authors.affiliation: Interfakultäres Institut für Zellbiologie, Abteilung Genetik der Tiere, Fachbereich für Biologie, Universität Tübingen, Auf der Morgenstelle 28, Tübingen, Germany. Electronic address: rolf.reuter@uni-tuebingen.de.
authors.forename: Rolf
authors.initials: R
authors.lastname: Reuter
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001483:Base Sequence; D004330:Drosophila / Q000196:embryology*; D029721:Drosophila Proteins / Q000378:metabolism*; D004742:Enhancer Elements, Genetic; D050980:GATA Transcription Factors / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D006434:Hemocytes / Q000378:metabolism*; D008648:Mesoderm / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D010957:Plasmids / Q000378:metabolism; D013045:Species Specificity; D014158:Transcription, Genetic
chemical_list: D029721:Drosophila Proteins; D050980:GATA Transcription Factors; C103965:srp protein, Drosophila
keywords: GATA; Gene regulation; Hemocytes; Serpent; Transcriptional regulation