从活跃促进体的分离转录
Amy C Seila1, J Mauro Calabrese, Stuart S Levine
1Koch Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Science (New York, N.Y.)
|December 6, 2008
概括
大多数基因以单向的方式启动转录. 这项研究揭示了蛋白质编码基因促进体的广泛分离转录,短RNA与活跃促进体区域相邻,表明对调节的平衡状态.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
背景情况:
- 传统上,通过RNA聚合酶II (RNAPII) 启动转录被认为是单向的.
- 准确的调节促进子活动和基因调节的机制仍在研究中.
研究的目的:
- 为了研究蛋白质编码基因促进者的分离转录现象.
- 为了描述转录起点位相关RNAs (TSSa-RNAs) 的性质和基因组位置.
主要方法:
- 北方斑分析用于检测和表征TSSa-RNAs.
- 染色体免疫沉 (ChIP) 评估基因组修饰 (H3K4me3,H3K79me2) 和促进体区域的RNAPII占用率.
主要成果:
- 有广泛的分离转录的证据,产生感觉和反感觉的短RNA,并肩支持活跃的促进体.
- 从20-90核酸开始的TSSa-RNAs表现出明显的位置偏差:反感觉峰在转录开始地点 (TSS) 的上游和感觉峰在下游.
- 转录启动的标志 (RNAPII,H3K4me3) 与TSSa-RNA位置共定位,而延长标志 (H3K79me2) 则在TSSs的下游发现.
结论:
- 短距离分离转录是活性蛋白编码基因促进体的共同特征.
- 这种分离的转录可能有助于维持促进子区域在以后基因调节的平衡状态.
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