First Author | Asai T | Year | 2012 |
Journal | Blood | Volume | 120 |
Issue | 8 | Pages | 1601-12 |
PubMed ID | 22776820 | Mgi Jnum | J:189173 |
Mgi Id | MGI:5444571 | Doi | 10.1182/blood-2011-11-393983 |
Citation | Asai T, et al. (2012) Necdin, a p53 target gene, regulates the quiescence and response to genotoxic stress of hematopoietic stem/progenitor cells. Blood 120(8):1601-12 |
abstractText | We recently defined a critical role for p53 in regulating the quiescence of adult hematopoietic stem cells (HSCs) and identified necdin as a candidate p53 target gene. Necdin is a growth-suppressing protein and the gene encoding it is one of several that are deleted in patients with Prader-Willi syndrome. To define the intrinsic role of necdin in adult hematopoiesis, in the present study, we transplanted necdin-null fetal liver cells into lethally irradiated recipients. We show that necdin-null adult HSCs are less quiescent and more proliferative than normal HSCs, demonstrating the similar role of necdin and p53 in promoting HSC quiescence during steady-state conditions. However, wild-type recipients repopulated with necdin-null hematopoietic stem/progenitor cells show enhanced sensitivity to irradiation and chemotherapy, with increased p53-dependent apoptosis, myelosuppression, and mortality. Necdin controls the HSC response to genotoxic stress via both cell-cycle-dependent and cell-cycle-independent mechanisms, with the latter occurring in a Gas2L3-dependent manner. We conclude that necdin functions as a molecular switch in adult hematopoiesis, acting in a p53-like manner to promote HSC quiescence in the steady state, but suppressing p53-dependent apoptosis in response to genotoxic stress. |