Tissue homeostasis is maintained through tight multimodal regulation of stem cells and their supporting cells (the niche), which provide both physical contact and stemness factors to maintain stem cell identity. During development, the size of the niche must be correctly established in order to recruit a proper number of stem cells. Later, stem cell-intrinsic factors, niche-signals, and niche-stem cell anchorage cooperatively regulate and maintain stem cells. Intriguingly, stem cells adjust their behavior to fit the needs of the organism upon certain environmental and physiological cues. However, intense research into stem cell regulation by intrinsic and niche-derived factors has so far revealed very little about how stem cell niches are established and how stem cells respond to external stimuli.
We use the Drosophila ovarian germline stem cells and intestinal stem cells to ingestigate: 1. How is the stem cell niche established? 2. How are stem cells maintained in the niche? 3. How do stem cells respond to diet and aging?
Lin, K-Y., Wang, W-D., Lin, C-H., Rastegari, E., Su, Y-H., Chang, Y-C., Chang, Y-T., Liao, Y-F., Pi, HW., Yu, B-Y., Chen, S-H., Lin, C-Y., Lu, M-Y., Su, T-Y., Tzou, F-Y., Chan, C-C., and Hsu, H-J*. (2020) Piwi Reduction in the Aged Niche Eliminates Germline Stem Cells via Toll-GSK3 Signaling. Nature Communications, 11, article number: 3147.
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Ke Y-T and Hsu H-J*, 2019, “Generation of Inducible Gene-Switched GAL4 Expressed in the Drosophila Female Germline Stem Cell Niche.”, G3-Genes Genomes Genetics, 9(6), 2007-2016.
Su Y-H, Rastegri E, Kao S-H, Lai C-M, Lin K-Y, Liao H-Y Wang M-H and Hsu H-J*, 2018, “Diet Regulates Membrane Extension and Survival of Niche Escort Cells for Germline Homeostasis via Insulin signaling”, Development, 145(7), dev159186.
Tseng C-Y, Su Y-H, Yang S-M, Lin K-Y, Lai C-M, Rastegari E, Amartuvshin O, Cho Y, Cai Y, Hsu H-J*, 2018, “Smad-Independent BMP Signaling in Somatic Cells Limits the Size of the Germline Stem Cell Pool.”, Stem cell reports, 11(3), 811-827. (
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Kao, S-H., Tseng, C-Y., Wan, C-L., Su, Y-H., Hsieh, C-C., Pi, H., and Hsu, H-J*. (2015) Aging and insulin signaling differentially control normal and tumorous germline stem cells. Aging Cell,14(1): 25-34.
Yang, S-A., Wang, W-D., Chen, C-T., Tseng, C-Y., Chen, Y-N., and Hsu, H-J*. (2013). FOXO/Fringe is necessary for maintenance of the germline stem cell niche in response to insulin insufficiency. Developmental Biology 382, 124-135.