H3 and H4 histone tails play a central role in the interactions of recombinant NCPs
H3 and H4 histone tails play a central role in the interactions of recombinant NCPs
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DOI：
10.1529/biophysj.106.093815
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发表时间：
2007-04-01
影响因子：
3.4
通讯作者：
Durand, Dominique
中科院分区：
文献类型：
--
作者：
Bertin, Aurelie;Renouard, Madalena;Durand, Dominique
利用小角度x射线散射，我们探测组蛋白尾部对核小体间相互作用和核小体构象的影响。为了深入了解H3和H4组蛋白尾部的具体作用，我们构建了完美的单分散重组核小体核心颗粒，或者完整地或剥夺了H3和H4组蛋白尾部（gH3gH4）。主要结果是H3和H4组蛋白尾部对于诱导ncp之间的吸引相互作用是必需的。对电位模型用于描述ncp之间的相互作用。在所有盐浓度下，gH3gH4 ncp之间的相互作用最好用排斥性相互作用来描述。对于完整的ncp，需要一个额外的吸引项，具有5-10 kT等和20埃范围，以解释单价盐大于50 mM的粒子间相互作用。在构象方面，溶液中完整的ncp与三维晶体中的ncp相似。相反，gH3gH4 ncp会产生略有不同的小角度x射线散射曲线，这可以理解为颗粒的更开放的构象，其中DNA末端与核心略有分离。
Using small-angle x-ray scattering, we probe the effect of histone tails on both internucleosomal interactions and nucleosome conformation. To get insight into the specific role of H3 and H4 histone tails, perfectly monodisperse recombinant nucleosome core particles were reconstituted, either intact or deprived of both H3 and H4 histone tails (gH3gH4). The main result is that H3 and H4 histone tails are necessary to induce attractive interactions between NCPs. A pair potential model was used to describe interactions between NCPs. At all salt concentrations, interactions between gH3gH4 NCPs are best described by repulsive interactions exclusively. For intact NCPs, an additional attractive term, with a 5-10 kT magnitude and 20 angstrom range, is required to account for interparticle interactions above 50 mM monovalent salt. Regarding conformation, intact NCPs in solution are similar to NCPs in 3D crystals. gH3gH4 NCPs instead give rise to slightly different small-angle x-ray scattering curves that can be understood as a more opened conformation of the particle, where DNA ends are slightly detached from the core.