1. Requirement of GSK-3 for PUMA induction upon loss of pro-survival PI3K signaling
- Author
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Juliane Rapp, Lisa Schlicher, Kerstin Stock, Prisca Brauns-Schubert, Céline Charvet, Ulrich Maurer, Christoph Borner, Florian Schubert, Manuela Wissler, and Martina Weiß
- Subjects
0301 basic medicine ,Cancer Research ,Programmed cell death ,medicine.medical_treatment ,Immunology ,Regulator ,Apoptosis ,Article ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,Glycogen Synthase Kinase 3 ,Phosphatidylinositol 3-Kinases ,0302 clinical medicine ,GSK-3 ,Puma ,hemic and lymphatic diseases ,Proto-Oncogene Proteins ,medicine ,Humans ,lcsh:QH573-671 ,Protein kinase B ,Gene knockout ,biology ,Chemistry ,lcsh:Cytology ,Growth factor ,Cell Biology ,biology.organism_classification ,HCT116 Cells ,Cell biology ,030104 developmental biology ,HEK293 Cells ,030220 oncology & carcinogenesis ,biological phenomena, cell phenomena, and immunity ,Apoptosis Regulatory Proteins ,Signal Transduction - Abstract
Growth factor withdrawal induces rapid apoptosis via mitochondrial outer membrane permeabilization. We had previously observed that cell death of IL-3-dependent Ba/F3 cells, induced by removal of the growth factor, required the activity of the kinase GSK-3. Employing CRISPR/Cas9-mediated gene knockout, we aimed to identify pro-apoptotic GSK-3 regulated factors in this process. Knockout of either Puma or Bim demonstrated that the induction of Puma, but not Bim, was crucial for apoptosis induced by IL-3 deprivation. Thus, we aimed at identifying the GSK-3-dependent PUMA regulator. Loss of FOXO3A reduced the induction of Puma, while additional loss of p53 completely repressed induction upon growth factor withdrawal. A constitutively active mutant of FOXO3A, which cannot be controlled by AKT directly, still required active GSK-3 for the full transcriptional induction of Puma and cell death upon IL-3 withdrawal. Thus, the suppression of GSK-3 is the key function of PI3K signaling in order to prevent the induction of Puma by FOXO3A and p53 and thereby apoptosis upon growth factor withdrawal.
- Published
- 2018