Transcription factor access to chromatin
Transcription factor access to chromatin
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DOI：
10.1093/nar/25.18.3559
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发表时间：
1997-09-15
影响因子：
14.9
通讯作者：
Eisfeld, K
中科院分区：
文献类型：
--
作者：
Beato, M;Eisfeld, K
基于基因组足迹数据和染色质重构实验，讨论了序列特异性转录因子如何进入核小体组织DNA中的同源位点的问题。提出了将转录因子分为两类：（1）启动因子，能够在规则核小体内结合其靶序列并启动导致染色质重构和反式激活的事件;（ii）效应因子，其不能结合常规核小体并且依赖于起始因子或依赖于预设的核小体结构以接近其在染色质中的靶序列。对MMTV启动子的研究表明，蛋白质-DNA接触的程度和数量决定了一种因子是否属于一类。启动因子只有少数DNA接触聚集在双螺旋的一侧，而效应因子有广泛的接触分布在整个圆周的DNA螺旋。因此，DNA识别的性质赋予序列特异性因子在基因调控事件的序列层次中的特定位置。
The question of how sequence-specific transcription factors access their cognate sites in nucleosomally organized DNA is discussed on the basis of genomic footprinting data and chromatin reconstitution experiments, A classification of factors into two categories is proposed: (i) initiator factors which are able to bind their target sequences within regular nucleosomes and initiate events leading to chromatin remodelling and transactivation; (ii) effector factors which are unable to bind regular nucleosomes and depend on initiator factors or on a pre-set nucleosomal structure for accessing their target sequences in chromatin. Studies with the MMTV promoter suggest that the extent and number of protein-DNA contacts determine whether a factor belongs to one or the other category. Initiator factors have only a few DNA contacts clustered on one side of the double helix, whereas effector factors have extensive contacts distributed throughout the whole circumference of the DNA helix. Thus, the nature of DNA recognition confers to sequence-specific factors their specific place in the sequential hierarchy of gene regulatory events.