| First Author | Bhandoola A | Year | 2000 |
| Journal | J Exp Med | Volume | 192 |
| Issue | 6 | Pages | 891-7 |
| PubMed ID | 10993919 | Mgi Jnum | J:112013 |
| Mgi Id | MGI:3655352 | Doi | 10.1084/jem.192.6.891 |
| Citation | Bhandoola A, et al. (2000) Immature thymocytes undergoing receptor rearrangements are resistant to an Atm-dependent death pathway activated in mature T cells by double-stranded DNA breaks. J Exp Med 192(6):891-7 |
| abstractText | Immature CD4(+)CD8(+) thymocytes rearrange their T cell receptor (TCR)-alpha gene locus to generate clonotypic alpha/beta TCR, after which a few cells expressing selectable TCR are signaled to further differentiate into mature T cells. Because of requirements for self-tolerance, immature CD4(+)CD8(+) thymocytes are programmed to die in the thymus in response to a variety of stimuli that do not induce death of mature T cells. We now demonstrate that, in contrast to all previously described stimuli, immature CD4(+)CD8(+) thymocytes are selectively more resistant than mature T cells to apoptotic death induced by DNA intercalating agents. Importantly, we demonstrate that DNA intercalating agents induce double-stranded DNA breaks in both immature thymocytes and mature T cells, but immature thymocytes tolerate these DNA breaks, whereas mature T cells are signaled to die by an Atm-dependent but p53-independent death mechanism. Thus, our results indicate that absence of an Atm-dependent but p53-independent pathway allows immature thymocytes to survive double-stranded DNA breaks. It is likely that the unique ability of immature thymocytes to survive DNA-damaging intercalating agents reflects their tolerance of double-stranded DNA breaks that occur normally during antigen receptor gene rearrangements. |
