限制、组蛋白和30纳米螺旋
Constraints, Histones, and the 30 Nanometer Spiral
摘要：
我们研究了核小体构型中包裹在组蛋白周围的一段DNA的机械稳定性。这项调查的假设是，这种包装安排的适当模型是一个弹性杆，是自由扭曲和扭曲的机械约束。我们发现，所需的限制，以稳定的nuclesome配置的数量是由段的长度，DNA缠绕在组蛋白线轴的次数，和具体的限制利用。虽然可以证明，原则上，四个约束条件足以确保核小体的稳定性，但必须做出适当的选择以保证这一最小数量的有效性。约束的最佳选择似乎与组蛋白八聚体表面上螺旋脊的存在有关。我们研究的特殊构型与30纳米螺旋有关，这是染色质中DNA的一种高阶组织。
英文摘要：
We investigate the mechanical stability of a segment of DNA wrapped around a histone in the nucleosome configuration. The assumption underlying this investigation is that the proper model for this packaging arrangement is that of an elastic rod that is free to twist and that writhes subject to mechanical constraints. We find that the number of constraints required to stabilize the nuclesome configuration is determined by the length of the segment, the number of times the DNA wraps around the histone spool, and the specific constraints utilized. While it can be shown that four constraints suffice, in principle, to insure stability of the nucleosome, a proper choice must be made to guarantee the effectiveness of this minimal number. The optimal choice of constraints appears to bear a relation to the existence of a spiral ridge on the surface of the histone octamer. The particular configuration that we investigate is related to the 30 nanometer spiral, a higher-order organization of DNA in chromatin.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
