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Wnt ligands regulate Tkv expression to constrain Dpp activity in the Drosophila ovarian stem cell niche.

ABSTRACT: Stem cell self-renewal versus differentiation is regulated by the niche, which provides localized molecules that favor self-renewal. In the Drosophila melanogaster female germline stem cell (GSC) niche, Decapentaplegic (Dpp), a fly transforming growth factor β molecule and well-established long-range morphogen, acts over one cell diameter to maintain the GSCs. Here, we show that Thickveins (Tkv; a type I receptor of Dpp) is highly expressed in stromal cells next to Dpp-producing cells and functions to remove excess Dpp outside the niche, thereby spatially restricting its activity. Interestingly, Tkv expression in these stromal cells is regulated by multiple Wnt ligands that are produced by the niche. Our data demonstrate a self-restraining mechanism by which the Drosophila ovarian GSC niche acts to define its own boundary.

SUBMITTER: Luo L

PROVIDER: S-EPMC4442805 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Wnt ligands regulate Tkv expression to constrain Dpp activity in the Drosophila ovarian stem cell niche.

Luo Lichao L Wang Huashan H Fan Chao C Liu Sen S Cai Yu Y

The Journal of cell biology 20150501 4

Stem cell self-renewal versus differentiation is regulated by the niche, which provides localized molecules that favor self-renewal. In the Drosophila melanogaster female germline stem cell (GSC) niche, Decapentaplegic (Dpp), a fly transforming growth factor β molecule and well-established long-range morphogen, acts over one cell diameter to maintain the GSCs. Here, we show that Thickveins (Tkv; a type I receptor of Dpp) is highly expressed in stromal cells next to Dpp-producing cells and functi ...[more]

PMID: 26008746

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