Coupling of Hedgehog and Hippo pathways promotes stem cell maintenance by stimulating proliferation.

ABSTRACT: It is essential to define the mechanisms by which external signals regulate adult stem cell numbers, stem cell maintenance, and stem cell proliferation to guide regenerative stem cell therapies and to understand better how cancers originate in stem cells. In this paper, we show that Hedgehog (Hh) signaling in Drosophila melanogaster ovarian follicle stem cells (FSCs) induces the activity of Yorkie (Yki), the transcriptional coactivator of the Hippo pathway, by inducing yki transcription. Moreover, both Hh signaling and Yki positively regulate the rate of FSC proliferation, both are essential for FSC maintenance, and both promote increased FSC longevity and FSC duplication when in excess. We also found that responses to activated Yki depend on Cyclin E induction while responses to excess Hh

SUBMITTER: Huang J 

PROVIDER: S-EPMC4018789 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature