Higher-Order Structure of the 30-nm Chromatin Fiber Revealed by Cryo-EM
Higher-Order Structure of the 30-nm Chromatin Fiber Revealed by Cryo-EM
复制标题
冷冻电镜揭示 30 纳米染色质纤维的高阶结构
作者：
Zhu Ping;Li Guohong
在真核生物中，基因组DNA按等级被包装成染色质。作为核小体阵列和高阶组织之间的中心水平染色质结构，30 nm染色质纤维及其动力学在调节基因转录的DNA可及性中起着至关重要的作用。然而，尽管经过了三十年的广泛努力，30纳米染色质纤维的高阶结构仍然没有得到解决和争议。我们最近在连接蛋白H1存在的情况下，从12个核小体阵列中重建了30 nm的染色质纤维，并在11 Å的分辨率下测定了它们的低温电镜结构（Song et al., Science 344, 376-380）。在这里，我们简要回顾了染色质纤维的高阶结构研究，主要集中在我们最近解决的低温电镜结构的见解。©2016 IUBMB生活，68(11):873-878,2016
Genomic DNA is hierarchically packaged into chromatin in eukaryotes. As a central‐level chromatin structure between nucleosomal arrays and higher order organizations, 30 nm chromatin fiber, and its dynamics play a crucial role in regulating DNA accessibility for gene transcription. However, despite extensive efforts over three decades, the higher‐order structure of the 30 nm chromatin fiber remains unresolved and controversial. We have recently reconstituted the 30 nm chromatin fibers from 12 nucleosomal arraysin vitroin the presence of linker histone H1, and determined their cryo‐EM structures at resolution of 11 Å (Song et al., Science 344, 376–380). Here, we briefly reviewed the higher‐order structure studies of chromatin fibers, mainly focusing on the insights from the cryo‐EM structures we recently solved. © 2016 IUBMB Life, 68(11):873–878, 2016