在缺乏p21的细胞中,抗癌药物诱导的S相脱和线粒分裂
T Waldman1, C Lengauer, K W Kinzler
1The Howard Hughes Medical Institute, Johns Hopkins Oncology Center, and Program in Human Genetics, Baltimore, Maryland 21231, USA.
Nature
|June 20, 1996
概括
蛋白质p21WAF1/CIP1对于协调人体细胞细胞循环阶段至关重要. 没有它,DNA受损的细胞会发生异常的细胞分裂,导致多化和亡.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 精确协调S (DNA合成) 和M (转化) 阶段的真核细胞循环对于细胞分裂和压力诱导的增长停止至关重要.
- 细胞检查点确保了细胞周期的正确进展,防止错误,例如在线粒体阻断后的额外S阶段,但哺乳动物细胞中的机制尚未完全理解.
研究的目的:
- 研究p21WAF1/CIP1在人类细胞S和M相协调中的作用.
- 阐明在DNA损伤压力下细胞循环协调的分子机制.
主要方法:
- 利用人类细胞系研究细胞周期进展.
- 研究了p21WAF1/CIP1在对DNA损伤的反应中的功能.
- 在缺乏p21WAF1/CIP1.1.的细胞中观察到核形态和DNA含量.
主要成果:
- 在没有p21WAF1/CIP1的情况下,DNA受损的人类细胞会停留在类似G2的状态中,但会经历额外的S阶段而没有正常的线粒分裂.
- 缺少p21WAF1/CIP1的细胞会产生变形的多倍体细胞核.
- 这些细胞随后经历了亡.
结论:
- p21WAF1/CIP1是人体细胞中S和M相协调所需的,作为关键检查点调节器.
- 失去p21WAF1/CIP1功能导致S/M相解,基因组不稳定性和细胞死亡.
- 了解这种机制可能有助于癌症治疗,因为临床上使用的破坏DNA的药物可能会导致类似的S/M脱.
相关概念视频
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