Fbxw7/Cdc4是一种p53-依赖的,具有哈普洛因不足的瘤抑制基因
Jian-Hua Mao1, Jesus Perez-Losada, Di Wu
1Cancer Research Institute, University of California at San Francisco, 2340 Sutter Street, San Francisco, California 94143, USA.
Nature
|December 14, 2004
概括
Fbxw7基因充当瘤抑制剂,其损失有助于癌症的发展,特别是在p53缺乏的小鼠中. 这种平时的瘤抑制基因是不够的.
科学领域:
- 在瘤学瘤学.
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 这种FBXW7/hCDC4基因编码了对染色体稳定性至关重要的一种乌比奎丁结合酶.
- 瘤发生是一种复杂的过程,涉及遗传突变和瘤抑制基因的丧失.
- p53通路是细胞循环停止和细胞亡的关键调节者,以应对DNA损伤.
研究的目的:
- 通过哺乳动物遗传查,识别参与瘤发生的p53依赖性瘤抑制基因.
- 研究小鼠Fbxw7基因在癌症发展中的作用及其与p53.3的关系.
- 了解Fbxw7损失导致遗传不稳定性和瘤形成的分子机制.
主要方法:
- 在辐射诱导淋巴瘤中寻找p53依赖基因的哺乳动物遗传选.
- 在p53+/-和p53-/-小鼠中分析Fbxw7基因的异构性损失和突变率.
- 在Fbxw7+/-小鼠和p53缺乏的小鼠中进行瘤谱分析.
- 在Fbxw7缺乏的小鼠胚胎纤维细胞和具有Fbxw7敲击的野生类型细胞中分析蛋白质水平 (Aurora-A激酶,c-Jun,Notch4,环素E).
主要成果:
- 鼠标Fbxw7基因被确定为一个p53依赖的瘤抑制剂.
- 在p53+/-小鼠的辐射诱导淋巴瘤中观察到频繁的异性损失和Fbxw7突变.
- Fbxw7的哈普隆缺陷增加了对辐射诱导的瘤发生的敏感性.
- 在p53缺乏的小鼠中,Fbxw7的丧失导致了更广泛的上皮瘤 (肺,肝,卵巢) 谱.
- 缺乏Fbxw7导致Aurora-A激酶,c-Jun和Notch4.4的水平升高.
结论:
- Fbxw7以p53-依赖的方式作为一个平分不充分的瘤抑制基因起作用.
- 丧失Fbxw7有助于遗传不稳定,可能是通过Aurora-A激酶激活.
- 这些发现为人类癌症中Fbxw7突变的早期发生提供了理由.
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