染色质高度紧密的折叠阻止了转录因子和辅因子与DNA的结合, 因而通过染色质重塑以解除这样的抑制环境, 对于转录活动的正常进行是至关重要的。目前认为, 染色质重塑至少是通过两种机制来完成的, 一种是通过ATP依赖的染色质改构复合物, 另一种是通过对组蛋白尾部进行共价修饰的组蛋白修饰酶复合物。文章结合近年来的研究进展, 对前者进行染色质重塑的机制及两者在基因转录调控过程中如何相互协作等进行了论述。
The highly condensed chromatin prevents binding of transcription factors and cofactors to DNA. Therefore, it is crucial to relief the repressive environment for transcription through chromatin remodeling activities. Recently, it is widely accepted that chromatin remodeling is carried out by at least two mechanisms: ATP-dependent chromatin remodeling complex and covalent modifications of histone tails by histone modification complexes. This paper reviews the mechanisms of chromatin remodeling through ATP-dependent chromatin remodeling complex and how the two complexes work together to modify the chromatin structure and regulate the function of transcription mechanism according to recent studies.
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