title: Mago Nashi and Tsunagi/Y14, respectively, regulate Drosophila germline stem cell differentiation and oocyte specification.
abstract: A protein complex consisting of Mago Nashi and Tsunagi/Y14 is required to establish the major body axes and for the localization of primordial germ cell determinants during Drosophila melanogaster oogenesis. The Mago Nashi:Tsunagi/Y14 heterodimer also serves as the core of the exon junction complex (EJC), a multiprotein complex assembled on spliced mRNAs. In previous studies, reduced function alleles of mago nashi and tsunagi/Y14 were used to characterize the roles of the genes in oogenesis. Here, we investigated mago nashi and tsunagi/Y14 using null alleles and clonal analysis. Germline clones lacking mago nashi function divide but fail to differentiate. The mago nashi null germline stem cells produce clones over a period of at least 11 days, suggesting that mago nashi is not necessary for stem cell self-renewal. However, germline stem cells lacking tsunagi/Y14 function are indistinguishable from wild type. Additionally, in tsunagi/Y14 null germline cysts, centrosomes and oocyte-specific components fail to concentrate within a single cell and oocyte fate is not restricted to a single cell. Together, our results suggest not only that mago nashi is required for germline stem cell differentiation but that surprisingly mago nashi functions independently of tsunagi/Y14 in this process. On the other hand, Tsunagi/Y14 is essential for restricting oocyte fate to a single cell and may function with mago nashi in this process.
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO 80309-0347, USA.
authors.forename: David H
authors.initials: DH
authors.lastname: Parma
authors.forename: Paul E
authors.initials: PE
authors.lastname: Bennett
authors.forename: Robert E
authors.initials: RE
authors.lastname: Boswell
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D002454:Cell Differentiation; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000166:cytology* / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D005260:Female; D018507:Gene Expression Regulation, Developmental; D017344:Genes, Insect; D005854:Germ Cells / Q000166:cytology* / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D009865:Oocytes / Q000166:cytology / Q000378:metabolism; D009866:Oogenesis / Q000235:genetics / Q000502:physiology*; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D029721:Drosophila Proteins; C107372:Mago protein, Drosophila; D009687:Nuclear Proteins; D016601:RNA-Binding Proteins; C440016:tsu protein, Drosophila