title: lines and bowl affect the specification of cyst stem cells and niche cells in the Drosophila testis.
abstract: To function properly, tissue-specific stem cells must reside in a niche. The Drosophila testis niche is one of few niches studied in vivo. Here, a single niche, comprising ten hub cells, maintains both germline stem cells (GSC) and somatic stem cells (CySC). Here, we show that lines is an essential CySC factor. Surprisingly, lines-depleted CySCs adopted several characteristics of hub cells, including the recruitment of new CySCs. This led us to examine the developmental relationship between CySCs and hub cells. In contrast to a previous report, we did not observe significant conversion of steady-state CySC progeny to hub fate. However, we found that these two cell types derive from a common precursor pool during gonadogenesis. Furthermore, lines mutant embryos exhibited gonads containing excess hub cells, indicating that lines represses hub cell fate during gonadogenesis. In many tissues, lines acts antagonistically to bowl, and we found that this is true for hub specification, establishing bowl as a positively acting factor in the development of the testis niche.
authors.affiliation: Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine and the Penn Institute for Regenerative Medicine, Philadelphia, PA 19104-6048, USA. sdinardo@zimbra.upenn.edu
authors.forename: Stephen
authors.initials: S
authors.lastname: Dinardo
authors.forename: Tishina
authors.initials: T
authors.lastname: Okegbe
authors.forename: Lindsey
authors.initials: L
authors.lastname: Wingert
authors.forename: Sarah
authors.initials: S
authors.lastname: Freilich
authors.forename: Natalie
authors.initials: N
authors.lastname: Terry
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D019521:Body Patterning / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics / Q000502:physiology*; D054337:Cell Dedifferentiation / Q000235:genetics / Q000502:physiology; D002454:Cell Differentiation / Q000235:genetics / Q000502:physiology; D049109:Cell Proliferation; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D004330:Drosophila / Q000196:embryology* / Q000235:genetics / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics / Q000502:physiology*; D004625:Embryo, Nonmammalian; D005854:Germ Cells / Q000166:cytology / Q000378:metabolism; D008297:Male; D055153:Stem Cell Niche; D013737:Testis / Q000166:cytology* / Q000196:embryology* / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*
chemical_list: D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D014157:Transcription Factors; C100532:bowl protein, Drosophila; C410902:lin protein, Drosophila