title: Companion Blood Cells Control Ovarian Stem Cell Niche Microenvironment and Homeostasis.
abstract: The extracellular matrix plays an essential role for stem cell differentiation and niche homeostasis. Yet, the origin and mechanism of assembly of the stem cell niche microenvironment remain poorly characterized. Here, we uncover an association between the niche and blood cells, leading to the formation of the Drosophila ovarian germline stem cell niche basement membrane. We identify a distinct pool of plasmatocytes tightly associated with the developing ovaries from larval stages onward. Expressing tagged collagen IV tissue specifically, we show that the germline stem cell niche basement membrane is produced by these "companion plasmatocytes" in the larval gonad and persists throughout adulthood, including the reproductive period. Eliminating companion plasmatocytes or specifically blocking their collagen IV expression during larval stages results in abnormal adult niches with excess stem cells, a phenotype due to aberrant BMP signaling. Thus, local interactions between the niche and blood cells during gonad development are essential for adult germline stem cell niche microenvironment assembly and homeostasis.
authors.affiliation: University of Nice Sophia Antipolis, Institut de Biologie Valrose, iBV, 06108 Nice, France; CNRS, Institut de Biologie Valrose, iBV, UMR 7277, 06108 Nice, France; INSERM, Institut de Biologie Valrose, iBV, U1091, 06108 Nice, France. Electronic address: vandebor@unice.fr.
authors.forename: Véronique
authors.initials: V
authors.lastname: Van De Bor
authors.affiliation: University of Nice Sophia Antipolis, Institut de Biologie Valrose, iBV, 06108 Nice, France; CNRS, Institut de Biologie Valrose, iBV, UMR 7277, 06108 Nice, France; INSERM, Institut de Biologie Valrose, iBV, U1091, 06108 Nice, France.
authors.forename: Geordie
authors.initials: G
authors.lastname: Zimniak
authors.affiliation: University of Nice Sophia Antipolis, Institut de Biologie Valrose, iBV, 06108 Nice, France; CNRS, Institut de Biologie Valrose, iBV, UMR 7277, 06108 Nice, France; INSERM, Institut de Biologie Valrose, iBV, U1091, 06108 Nice, France.
authors.forename: Lise
authors.initials: L
authors.lastname: Papone
authors.affiliation: University of Nice Sophia Antipolis, Institut de Biologie Valrose, iBV, 06108 Nice, France; CNRS, Institut de Biologie Valrose, iBV, UMR 7277, 06108 Nice, France; INSERM, Institut de Biologie Valrose, iBV, U1091, 06108 Nice, France.
authors.forename: Delphine
authors.initials: D
authors.lastname: Cerezo
authors.affiliation: Institut de Génomique Fonctionnelle de Lyon-ENS de Lyon, CNRS UMR 5242, INRA USC 1370, 46, allée d'Italie, 69364 Lyon Cedex 07, France.
authors.forename: Marilyne
authors.initials: M
authors.lastname: Malbouyres
authors.affiliation: University of Nice Sophia Antipolis, Institut de Biologie Valrose, iBV, 06108 Nice, France; CNRS, Institut de Biologie Valrose, iBV, UMR 7277, 06108 Nice, France; INSERM, Institut de Biologie Valrose, iBV, U1091, 06108 Nice, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Juan
authors.affiliation: Institut de Génomique Fonctionnelle de Lyon-ENS de Lyon, CNRS UMR 5242, INRA USC 1370, 46, allée d'Italie, 69364 Lyon Cedex 07, France.
authors.forename: Florence
authors.initials: F
authors.lastname: Ruggiero
authors.affiliation: University of Nice Sophia Antipolis, Institut de Biologie Valrose, iBV, 06108 Nice, France; CNRS, Institut de Biologie Valrose, iBV, UMR 7277, 06108 Nice, France; INSERM, Institut de Biologie Valrose, iBV, U1091, 06108 Nice, France. Electronic address: noselli@unice.fr.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Noselli
mesh_terms: D000818:Animals; D024141:Collagen Type IV / Q000378:metabolism; D004330:Drosophila / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D005109:Extracellular Matrix / Q000378:metabolism; D006434:Hemocytes / Q000166:cytology* / Q000378:metabolism; D006706:Homeostasis; D009866:Oogenesis; D009867:Oogonia / Q000166:cytology* / Q000378:metabolism; D055153:Stem Cell Niche
chemical_list: D024141:Collagen Type IV
keywords: Drosophila ovary; basement membrane; collagen type IV; extracellular matrix; hemocytes; stem cell niche