| First Author | Townsend PA | Year | 2005 |
| Journal | J Cell Sci | Volume | 118 |
| Issue | Pt 8 | Pages | 1629-39 |
| PubMed ID | 15784679 | Mgi Jnum | J:97547 |
| Mgi Id | MGI:3575623 | Doi | 10.1242/jcs.01728 |
| Citation | Townsend PA, et al. (2005) STAT-1 facilitates the ATM activated checkpoint pathway following DNA damage. J Cell Sci 118(Pt 8):1629-39 |
| abstractText | STAT-1 plays a role in mediating stress responses to various stimuli and has also been implied to be a tumour suppressor. Here, we report that STAT-1-deficient cells have defects both in intra-S-phase and G2-M checkpoints in response to DNA damage. Interestingly, STAT-1-deficient cells showed reduced Chk2 phosphorylation on threonine 68 (Chk2(-T68)) following DNA damage, suggesting that STAT-1 might function in the ATM-Chk2 pathway. Moreover, the defects in Chk2(-T68) phosphorylation in STAT-1-deficient cells also correlated with reduced degradation of Cdc25A compared with STAT-1-expressing cells after DNA damage. We also show that STAT-1 is required for ATM-dependent phosphorylation of NBS1 and p53 but not for BRCA1 or H2AX phosphorylation following DNA damage. Expression levels of BRCT mediator/adaptor proteins MDC1 and 53BP1, which are required for ATM-mediated pathways, are reduced in cells lacking STAT-1. Enforced expression of MDC1 into STAT-1-deficient cells restored ATM-mediated phosphorylation of downstream substrates. These results imply that STAT-1 plays a crucial role in the DNA-damage-response by regulating the expression of 53BP1 and MDC1, factors known to be important for mediating ATM-dependent checkpoint pathways. |
