Bunz F, Dutriaux A, Lengauer C, Waldman T, Zhou S, Brown J P, Sedivy J M, Kinzler K W, Vogelstein B
The Howard Hughes Medical Institute and The Johns Hopkins Oncology Center, 424 North Bond Street, Baltimore, MD 21231, USA.
Science. 1998 Nov 20;282(5393):1497-501. doi: 10.1126/science.282.5393.1497.
After DNA damage, many cells appear to enter a sustained arrest in the G2 phase of the cell cycle. It is shown here that this arrest could be sustained only when p53 was present in the cell and capable of transcriptionally activating the cyclin-dependent kinase inhibitor p21. After disruption of either the p53 or the p21 gene, gamma radiated cells progressed into mitosis and exhibited a G2 DNA content only because of a failure of cytokinesis. Thus, p53 and p21 appear to be essential for maintaining the G2 checkpoint in human cells.
DNA损伤后,许多细胞似乎会在细胞周期的G2期进入持续停滞状态。本文表明,只有当细胞中存在p53且其能够转录激活细胞周期蛋白依赖性激酶抑制剂p21时,这种停滞状态才能持续。在p53或p21基因被破坏后,经γ射线照射的细胞进入有丝分裂,并且仅由于胞质分裂失败而呈现G2期DNA含量。因此,p53和p21似乎对于维持人类细胞中的G2检查点至关重要。