Whether aged hematopoietic stem and progenitor cells (HSPCs) have impaired DNA damage repair is controversial. Using a combination of DNA mutation indicator assays, we observe a 2- to 3-fold increase in the number of DNA mutations in the hematopoietic system upon aging. Young and aged hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs) do not show an increase in mutation upon irradiation-induced DNA damage repair, and young and aged HSPCs respond very similarly to DNA damage with respect to cell-cycle checkpoint activation and apoptosis. Both young and aged HSPCs show impaired activation of the DNA-damage-induced G1-S checkpoint. Induction of chronic DNA double-strand breaks by zinc-finger nucleases suggests that HSPCs undergo apoptosis rather than faulty repair. These data reveal a protective mechanism in both the young and aged hematopoietic system against accumulation of mutations in response to DNA damage.
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http://dx.doi.org/10.1016/j.celrep.2015.11.030 | DOI Listing |
Proc Natl Acad Sci U S A
January 2025
Department of Immunology and Microbiology, Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong 510000, China.
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State Research Center-Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, 123098, Moscow, Russia.
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View Article and Find Full Text PDFCell Mol Life Sci
January 2025
Institute of Endotypes in Oncology, Metabolism, and Immunology, National Research Council, Via Pietro Castellino 111, Naples, Italy.
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View Article and Find Full Text PDFJ Bacteriol
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Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
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View Article and Find Full Text PDFProteomes
January 2025
Instituto de Matemática e Estatística, Departamento de Ciência da Computação, Universidade de São Paulo, Rua do Matão 1010, São Paulo 05508-090, SP, Brazil.
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