Live imaging of Drosophila melanogaster neural stem cells with photo-ablated centrosomes.
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ABSTRACT:
SUBMITTER: Thomas A
PROVIDER: S-EPMC9249821 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:As the biology of hematopoietic stem cells (HSCs) has been predominantly studied under transplantation conditions, it has been challenging to study dynamic HSC behaviors in their native niche given under steady state conditions. Here, we describe the generation of a double knock-in fluorescent reporter that restricts the reporter labeling exclusively to the LT-HSC compartment. Single cell RNAseq comparing previously published LSK signatures (GEO: GSE90742) to our sorted fluorescently labeled cells (sorted without the use of any other cell surface markers) demonstrates that the fluorescently marked cells in our unique mouse model are exclusively found in the LT-HSC compartment in terms of their overal RNA content. This confirms that the generated mice label LT-HSCs in a highly specific manner.
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Project description:Many types of normal and cancer stem cells are resistant to killing by genotoxins, but the mechanism for this resistance is poorly understood. Here we show that adult stem cells in Drosophila melanogaster germline and midgut are resistant to ionizing radiation (IR) or chemically induced apoptosis and dissect the mechanism for this protection. We find that upon IR the receptor tyrosine kinase Tie/Tie-2 is activated, leading to the upregulation of microRNA bantam that represses FOXO-mediated transcription of pro-apoptotic Smac/DIABLO orthologue, Hid in germline stem cells. Knockdown of the IR-induced putative Tie ligand, Pvf1, a functional homologue of human Angiopoietin, in differentiating daughter cells renders germline stem cells sensitive to IR, suggesting that the dying daughters send a survival signal to protect their stem cells for future repopulation of the tissue. If conserved in cancer stem cells, this mechanism may provide therapeutic options for the eradication of cancer.
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