序列特异性转录因子从线粒体染色质的移位
M A Martínez-Balbás1, A Dey, S K Rabindran
1Laboratory of Biochemistry, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
Cell
|October 6, 1995
概括
在线粒分裂过程中,压力诱导的人类热冲击蛋白70 (hsp70) 基因表达被抑制. 转录因子被从hsp70促进体中取代,这表明染色质结构影响了这种线粒抑制.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
背景情况:
- 转录活动通常在线粒分裂过程中受到抑制.
- 受压力诱导的人类热冲击蛋白70 (hsp70) 基因的表达在线粒分裂过程中被废除.
研究的目的:
- 为了研究在转化过程中抑制hsp70基因表达的潜在机制.
- 确定转录因子和染色质结构在线粒抑制中的作用.
主要方法:
- 在线粒细胞提取物中分析转录因子 (C/EBP,GBP,HSF1,Sp1) 的DNA结合活性.
- 在体内足迹和免疫细胞化学分析以评估转录因子局部化.
- DNase I 过敏性测试用于评估染色质结构.
主要成果:
- 虽然C/EBP,GBP和HSF1的结合活动正常,但Sp1在线粒分裂过程中对hsp70促进体的结合减少.
- 所有序列特异性转录因子都在线粒分裂过程中从促进子序列和大量染色质中被取代.
- 线性染色体在hsp70促进体上保留了DNase I过敏性,表明它没有按照正规的核细胞结构组织.
结论:
- 染色质凝聚与转录因子位移相关,这表明染色质结构在hsp70.0.的线粒抑制中发挥了作用.
- 转录因子从线粒染色体的移位提供了一个潜在的机制,可以在线粒分裂后重置转录程序.
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