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Updated: Jan 9, 2026
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在转变的甲状腺细胞中通过5-azacytidine重新激活甲状腺蛋白基因表达
E V Avvedimento1, S Obici, M Sanchez
1Institute of Cancer Research, Columbia University, New York, New York 10032.
Cell
|September 22, 1989
概括
拉斯转换的老鼠甲状腺细胞失去了甲状腺蛋白 (Tg) 的表达. 重新激活Tg促进体需要5-阿扎西丁治疗,以恢复甲状腺特异性核因子TgTF1,该核因子在Ras重激活时会丢失.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 癌症研究 癌症研究
背景情况:
- 转变的小鼠甲状腺细胞表现出抑制的甲状腺蛋白 (Tg) 表达.
- 基尔斯小鼠肉瘤病毒转化细胞在不允许的温度下失去转化表型,但Tg促进体仍然不活跃.
研究的目的:
- 调查拉斯转化细胞中铁血球蛋白促进体沉默背后的机制.
- 探索DNA甲基化和转录因子在Tg基因调节中的作用.
主要方法:
- 在转变的小鼠甲状腺细胞中利用了对温度敏感的Ras等位基因.
- 雇佣记者基因测试 (Tg促进剂-新米素耐药性) 来评估促进剂活性.
- 使用了DNA脱甲基化剂5-azacytidine.
- 使用分子技术检测出甲状腺特异性核因子TgTF1.
主要成果:
- 甲状腺球蛋白促进剂在转化细胞中保持不活跃,即使在表型逆转后.
- 5-阿扎丁治疗重新激活了Tg促进剂,并赋予了G418的耐药性.
- 与TgTF1.1存在相关的Tg促进剂活性.
- 在转化细胞中,TgTF1无法检测,但在接受5 - 亚扎丁治疗后再次出现.
- 拉斯活性恢复导致TgTF1和G418抗性的快速丧失.
结论:
- 拉斯转化诱导了甲状腺蛋白促进体的表观遗传沉默.
- 脱甲基化DNA和恢复TgTF1对于重新激活Tg促进体至关重要.
- 拉斯信号负面调节TgTF1的表达,有助于甲状腺脱差.
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