title: Drosophila morgue influences cell numbers and positions in the embryonic nervous system.
abstract: Morgue is a unique multi-domain protein that contains a zinc finger motif, an F box, and a variant E2 conjugase domain. The presence of these domains suggests potentially complex and novel functions for Morgue in ubiquitination pathways. Morgue was originally identified via its gain-of-function enhancement of eye cell death phenotypes in Drosophila and ectopic expression of Morgue also influences circadian rhythms. However, there is as yet little known about Morgues normal developmental or physiological functions. To address this issue, we generated several morgue loss-of-function mutants via P element excision mutagenesis and analyzed the mutant phenotypes during the fly life cycle. These studies revealed that morgue null mutants are viable, though approximately 10% of the mutants exhibit defects in pupal spiracle eversion and malformations in the adult abdominal cuticle. In addition, a similar subset of morgue mutant embryos exhibited alterations in the normal number, position, or morphology of specific neurons and glia. Analysis of Morgue protein localization was addressed through generation of a transgenic fly strain that expresses a GFP::Morgue fusion protein. Use of this strain revealed Morgue protein localization in multiple cellular compartments, including nuclei, cytoplasm and membranes. Taken together, these diverse phenotypes and distribution patterns suggest pleiotropic functions for Morgue.
authors.affiliation: Biology Department, University of Massachusetts, Amherst MA, USA.
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Schreader
authors.forename: Yiqin
authors.initials: Y
authors.lastname: Wang
authors.forename: Stephanie
authors.initials: S
authors.lastname: Carter
authors.forename: Joanna
authors.initials: J
authors.lastname: Grigas
authors.forename: John R
authors.initials: JR
authors.lastname: Nambu
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D002452:Cell Count; D016923:Cell Death; D029721:Drosophila Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000196:embryology* / Q000235:genetics* / Q000378:metabolism; D005136:Eye Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D044782:F-Box Motifs / Q000235:genetics; D009154:Mutation; D009420:Nervous System / Q000737:chemistry / Q000196:embryology; D009457:Neuroglia / Q000166:cytology*; D009474:Neurons / Q000166:cytology*; D016133:Polymerase Chain Reaction; D011679:Pupa / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D054875:Ubiquitination; D016335:Zinc Fingers
chemical_list: D029721:Drosophila Proteins; D005136:Eye Proteins; D011993:Recombinant Fusion Proteins; C460739:morgue protein, Drosophila