Phosphatidylinositol-3 kinase signaling controls survival and stemness of hematopoietic stem and progenitor cells.
Sasja Blokzijl-FrankeBas PonsioenStefan Schulte-MerkerPhilippe HerbomelKarima KissaSuma ChoorapoikayilJeroen den HertogPublished in: Oncogene (2021)
Hematopoietic stem and progenitor cells (HSPCs) are multipotent cells giving rise to all blood lineages during life. HSPCs emerge from the ventral wall of the dorsal aorta (VDA) during a specific timespan in embryonic development through endothelial hematopoietic transition (EHT). We investigated the ontogeny of HSPCs in mutant zebrafish embryos lacking functional pten, an important tumor suppressor with a central role in cell signaling. Through in vivo live imaging, we discovered that in pten mutant embryos a proportion of the HSPCs died upon emergence from the VDA, an effect rescued by inhibition of phosphatidylinositol-3 kinase (PI3K). Surprisingly, inhibition of PI3K in wild-type embryos also induced HSPC death. Surviving HSPCs colonized the caudal hematopoietic tissue (CHT) normally and committed to all blood lineages. Single-cell RNA sequencing indicated that inhibition of PI3K enhanced survival of multipotent progenitors, whereas the number of HSPCs with more stem-like properties was reduced. At the end of the definitive wave, loss of Pten caused a shift to more restricted progenitors at the expense of HSPCs. We conclude that PI3K signaling tightly controls HSPCs survival and both up- and downregulation of PI3K signaling reduces stemness of HSPCs.
Keyphrases
- single cell
- wild type
- cell proliferation
- stem cells
- protein kinase
- pi k akt
- spinal cord
- rna seq
- bone marrow
- epithelial mesenchymal transition
- tyrosine kinase
- free survival
- high resolution
- signaling pathway
- induced apoptosis
- endothelial cells
- cell cycle arrest
- radiation therapy
- pulmonary artery
- aortic valve
- mass spectrometry
- mesenchymal stem cells
- cell therapy
- photodynamic therapy
- pulmonary arterial hypertension
- deep brain stimulation
- fluorescence imaging