Nucleosome arrays reveal the two-start organization of the chromatin fiber
Nucleosome arrays reveal the two-start organization of the chromatin fiber
复制标题
DOI：
10.1126/science.1103124
复制
发表时间：
2004-11-26
期刊：
影响因子：
56.9
通讯作者：
Richmond, TJ
中科院分区：
文献类型：
--
作者：
Dorigo, B;Schalch, T;Richmond, TJ
染色质折叠决定了DNA组成真核生物基因组的可及性，因此在基因调控等核过程机制中非常重要。核小体排列紧密形成一个30纳米的染色质纤维，其结构至今仍有争议。已经提出了两类相互竞争的模型，其中核小体要么以单起点高阶螺旋的形式线性排列，要么以双起点螺旋的形式来回曲折排列。我们分析了通过引入二硫键交联稳定的紧凑的核小体阵列，并表明染色质纤维包括符合双起始模型的核小体的两个堆叠雅阁。
Chromatin folding determines the accessibility of DNA constituting eukaryotic genomes and consequently is profoundly important in the mechanisms of nuclear processes such as gene regulation. Nucleosome arrays compact to form a 30-nanometer chromatin fiber of hitherto disputed structure. Two competing classes of models have been proposed in which nucleosomes are either arranged linearly in a one-start higher order helix or zigzag back and forth in a two-start helix. We analyzed compacted nucleosome arrays stabilized by introduction of disulfide cross-links and show that the chromatin fiber comprises two stacks of nucleosomes in accord with the two-start model.