title: Exonuclease 1 is essential for maintaining genomic stability and the proliferative capacity of neural but not hematopoietic stem cells.
abstract: Exonuclease 1 (Exo1) has been implicated in the regulation of DNA damage responses in stem cells with dysfunctional telomeres. However, it is unclear whether Exo1-mediated DNA maintenance pathways play a role in the maintenance of genomic stability and the self-renewal of tissue stem cells in mice with functional telomeres. Here, we analyzed the proliferative capacity of neural stem cells (NSCs) and hematopoietic stem cells (HSCs) from Exo1(-/-) mice. Our study shows that Exo1 deficiency impairs the maintenance of genomic stability and proliferative capacity in NSCs but not HSCs. In line with these results, we detected a decrease in proliferation and an up-regulation of p21 expression levels in Exo1-deficient NSCs but not Exo1-deficient HSCs. Our data provide experimental evidence that Exo1 deficiency has a differential impact on the homeostasis and proliferative capacity of tissue stem cells in the brain and bone marrow, suggesting that different tissue stem cells utilize distinct mechanisms for maintaining their genomic stability. Our current study provides important insight into the role of Exo1-mediated DNA maintenance pathways in the maintenance of genomic stability and the proliferative capacity of tissue stem cells.
authors.affiliation: Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China; Institute of Aging Research, School of Medicine, Hangzhou Normal University School of Medicine, Hangzhou, China.
authors.forename: Junling
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Institute of Aging Research, School of Medicine, Hangzhou Normal University School of Medicine, Hangzhou, China.
authors.forename: Runan
authors.initials: R
authors.lastname: Yang
authors.affiliation: Department of Pharmaceutical Sciences and Winthrop P. Rockefeller Cancer Institute, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
authors.forename: Daohong
authors.initials: D
authors.lastname: Zhou
authors.affiliation: Leibniz Institute for Age Research, Fritz Lipmann Institute, Beutenbergstrasse 11, 07745 Jena, Germany.
authors.forename: Karl Lenhard
authors.initials: KL
authors.lastname: Rudolph
authors.affiliation: Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China.
authors.forename: Aimin
authors.initials: A
authors.lastname: Meng
authors.affiliation: Institute of Aging Research, School of Medicine, Hangzhou Normal University School of Medicine, Hangzhou, China. Electronic address: zhenyuju@163.com.
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Ju
mesh_terms: D000818:Animals; D049109:Cell Proliferation; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000378:metabolism; D004249:DNA Damage / Q000187:drug effects; D004260:DNA Repair; D005090:Exodeoxyribonucleases / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D042822:Genomic Instability; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000201:enzymology / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D058953:Neural Stem Cells / Q000166:cytology* / Q000201:enzymology* / Q000637:transplantation; D009830:Olfactory Bulb / Q000503:physiopathology; D017382:Reactive Oxygen Species / Q000633:toxicity; D015854:Up-Regulation
chemical_list: D050759:Cyclin-Dependent Kinase Inhibitor p21; D017382:Reactive Oxygen Species; D005090:Exodeoxyribonucleases; C028450:exodeoxyribonuclease I