Project description:Quiescent stem cells are periodically activated to maintain tissue homeostasis or occasionally called into action upon injury. Molecular mechanisms that constitutively maintain stem cell identity or promote stem cell proliferation and differentiation upon activation have been extensively studied. However, it is unclear how quiescent stem cells maintain identity and reinforce quiescence when they transition from quiescence to activation. Here we show mouse hair follicle stem cell compartment induces a transcription factor, Foxc1, when activated. Importantly, deletion of Foxc1 in the activated but not quiescent stem cells compromises stem cell identity, fails to re-establish quiescence and subsequently drives premature stem cell activation.These findings uncover a dynamic, cell-intrinsic mechanism employed by hair follicle stem cells to reinforce stemness in response to activation. Poly(A)-enriched transcriptome RNA-seq on HFSCs isolated in WT and K14Cre cKO mice at anagen and early telogen stage of hair cycle.
Project description:Hair follicle stem cells(HFSCs) can transition between active and quiescent stages during normal hair cycle or would healing. Transcriptional regulation has been show to regulate the transition. Previous studies have shown that two transcription factor, Foxc1 and Nfatc1, can help maintain the stem cells in quiescent state, the deletion of either one could lead to precocious activation. Here, we collect the hair follicle stem cell at postnatal day 30 from both control mice, Nfatc1 knockout mice, Foxc1 knockout mice(downloaded) and Foxc1/Nfatc1 double knockout mice to study the transcriptional regulation network of HFSCs quiescence.
Project description:Quiescent stem cells are periodically activated to maintain tissue homeostasis or occasionally called into action upon injury. Molecular mechanisms that constitutively maintain stem cell identity or promote stem cell proliferation and differentiation upon activation have been extensively studied. However, it is unclear how quiescent stem cells maintain identity and reinforce quiescence when they transition from quiescence to activation. Here we show mouse hair follicle stem cell compartment induces a transcription factor, Foxc1, when activated. Importantly, deletion of Foxc1 in the activated but not quiescent stem cells compromises stem cell identity, fails to re-establish quiescence and subsequently drives premature stem cell activation.These findings uncover a dynamic, cell-intrinsic mechanism employed by hair follicle stem cells to reinforce stemness in response to activation.
Project description:Quiescent stem cells are periodically activated to maintain tissue homeostasis or occasionally called into action upon injury. Molecular mechanisms that constitutively maintain stem cell identity or promote stem cell proliferation and differentiation upon activation have been extensively studied. However, it is unclear how quiescent stem cells maintain identity and reinforce quiescence when they transition from quiescence to activation. Here we show mouse hair follicle stem cell compartment induces a transcription factor, Foxc1, when activated. Importantly, deletion of Foxc1 in the activated but not quiescent stem cells compromises stem cell identity, fails to re-establish quiescence and subsequently drives premature stem cell activation.These findings uncover a dynamic, cell-intrinsic mechanism employed by hair follicle stem cells to reinforce stemness in response to activation.
Project description:We report downstream gene expression changes in stem cells of the adult mouse hair follicle upon conditional ablating of the transcription factor Forkhead Box C1 transcription factor (FOXC1). Hair follicles undergo cycles of rest (telogen; Tel) and regeneration (anagen; Ana). As such, we performed our analysis on these two different stages of hair follicles. mRNA-sequencing of WT vs. Foxc1-conditional or inducible KO (Foxc1-cKO or iKO) hair follicle stem cells (HFSCs) purified from mouse dorsal back skin by flow-activated cell sorting (FACS).
Project description:In many organs, adult stem cells are uniquely poised to serve as cancer cells of origin. In the epidermis, hair follicle stem cells (HFSCs) cycle through stages of quiescence (telogen) and proliferation (anagen) to drive hair growth. Within the hair follicle, HFSCs are capable of initiating squamous cell carcinoma, yet it is unclear how the hair cycle contributes to tumorigenesis. The data presented here show that HFSCs are unable to initiate tumors during the quiescent phase of the hair cycle, indicating that the mechanisms that keep HFSCs dormant are dominant to gain of oncogenes (Ras) or loss of tumor suppressors (p53). Instead, prolonged oncogenic stimuli only exert their effects when HFSC quiescence mechanisms are removed by normal HFSC activation. Furthermore, Pten activity is necessary for quiescence based tumor suppression, since Pten deletion alleviates this stem cell specific ability without affecting proliferation per se. Small RNAs were cloned from Trizol-lysed cells sorted from mouse skin and sequenced with the Illumina HiSeq2000.
Project description:We report downstream gene expression changes in stem cells of the adult mouse hair follicle upon conditional ablating of the transcription factor Forkhead Box C1 transcription factor (FOXC1). Hair follicles undergo cycles of rest (telogen; Tel) and regeneration (anagen; Ana). As such, we performed our analysis on these two different stages of hair follicles.