First Author | Konishi A | Year | 2008 |
Journal | Genes Dev | Volume | 22 |
Issue | 9 | Pages | 1221-30 |
PubMed ID | 18451109 | Mgi Jnum | J:134654 |
Mgi Id | MGI:3789452 | Doi | 10.1101/gad.1634008 |
Citation | Konishi A, et al. (2008) Cell cycle control of telomere protection and NHEJ revealed by a ts mutation in the DNA-binding domain of TRF2. Genes Dev 22(9):1221-30 |
abstractText | TRF2 is a component of shelterin, the telomere-specific protein complex that prevents DNA damage signaling and inappropriate repair at the natural ends of mammalian chromosomes. We describe a temperature-sensitive (ts) mutation in the Myb/SANT DNA-binding domain of TRF2 that allows controlled and reversible telomere deprotection. At 32 degrees C, TRF2ts was functional and rescued the lethality of TRF2 deletion from conditional TRF2(F/-) mouse embryonic fibroblasts (MEFs). When shifted to the nonpermissive temperature (37 degrees C), TRF2ts cells showed extensive telomere damage resulting in activation of the ATM kinase and nonhomologous end-joining (NHEJ) of chromosome ends. The inactivation of TRF2ts at 37 degrees C was rapid and reversible, permitting induction of short periods (3-6 h) of telomere dysfunction in the G0, G1, and S/G2 phases of the cell cycle. The results indicate that both the induction of telomere dysfunction and the re-establishment of the protected state can take place throughout interphase. In contrast, the processing of dysfunctional telomeres by NHEJ occurred primarily in G1, being repressed in S/G2 in a cyclin-dependent kinase (CDK)-dependent manner. |