DNA damage responses in human induced pluripotent stem cells and embryonic stem cells
| Autor: | Sandra Varum, Gerald Schatten, Jamie L. Fornsaglio, Olga Momčilović, Charles A. Easley, Leah Knobloch |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
Pluripotent Stem Cells
DNA Repair Cellular differentiation Blotting Western lcsh:Medicine Cell Cycle Proteins Biology Polymerase Chain Reaction Cell Line 03 medical and health sciences 0302 clinical medicine Humans CHEK1 Phosphorylation Induced pluripotent stem cell lcsh:Science Cell potency Embryonic Stem Cells 030304 developmental biology 0303 health sciences Biochemistry/Replication and Repair Multidisciplinary Microscopy Confocal Gene Expression Profiling lcsh:R Cell Cycle Cell Differentiation G2-M DNA damage checkpoint Flow Cytometry Embryonic stem cell Immunohistochemistry Cell biology Developmental Biology/Stem Cells 030220 oncology & carcinogenesis lcsh:Q Stem cell Reprogramming DNA Damage Research Article Developmental Biology |
| Zdroj: | PLoS ONE PLoS ONE, Vol 5, Iss 10, p e13410 (2010) |
| ISSN: | 1932-6203 |
| Popis: | Background: Induced pluripotent stem (iPS) cells have the capability to undergo self-renewal and differentiation into all somatic cell types. Since they can be produced through somatic cell reprogramming, which uses a defined set of transcription factors, iPS cells represent important sources of patient-specific cells for clinical applications. However, before these cells can be used in therapeutic designs, it is essential to understand their genetic stability. Methodology/Principal Findings: Here, we describe DNA damage responses in human iPS cells. We observe hypersensitivity to DNA damaging agents resulting in rapid induction of apoptosis after γ-irradiation. Expression of pluripotency factors does not appear to be diminished after irradiation in iPS cells. Following irradiation, iPS cells activate checkpoint signaling, evidenced by phosphorylation of ATM, NBS1, CHEK2, and TP53, localization of ATM to the double strand breaks (DSB), and localization of TP53 to the nucleus of NANOG-positive cells. We demonstrate that iPS cells temporary arrest cell cycle progression in the G2 phase of the cell cycle, displaying a lack of the G1/S cell cycle arrest similar to human embryonic stem (ES) cells. Furthermore, both cell types remove DSB within six hours of γ-irradiation, form RAD51 foci and exhibit sister chromatid exchanges suggesting homologous recombination repair. Finally, we report elevated expression of genes involved in DNA damage signaling, checkpoint function, and repair of various types of DNA lesions in ES and iPS cells relative to their differentiated counterparts. Conclusions/Significance: High degrees of similarity in DNA damage responses between ES and iPS cells were found. Even though reprogramming did not alter checkpoint signaling following DNA damage, dramatic changes in cell cycle structure, including a high percentage of cells in the S phase, increased radiosensitivity and loss of DNA damage-induced G1/S cell cycle arrest, were observed in stem cells generated by induced pluripotency. © 2010 Momcilovic et al. |
| Databáze: | OpenAIRE |
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