Biology Department, University of Massachusetts, Amherst, Massachusetts 01003, USA.
Cold Spring Harb Perspect Biol. 2010 May;2(5):a000596. doi: 10.1101/cshperspect.a000596. Epub 2010 Apr 7.
The primary role of the nucleus as an information storage, retrieval, and replication site requires the physical organization and compaction of meters of DNA. Although it has been clear for many years that nucleosomes constitute the first level of chromatin compaction, this contributes a relatively small fraction of the condensation needed to fit the typical genome into an interphase nucleus or set of metaphase chromosomes, indicating that there are additional "higher order" levels of chromatin condensation. Identifying these levels, their interrelationships, and the principles that govern their occurrence has been a challenging and much discussed problem. In this article, we focus on recent experimental advances and the emerging evidence indicating that structural plasticity and chromatin dynamics play dominant roles in genome organization. We also discuss novel approaches likely to yield important insights in the near future, and suggest research areas that merit further study.
核作为信息存储、检索和复制的主要场所，需要对数米长的 DNA 进行物理组织和压缩。尽管多年来人们已经清楚核小体构成了染色质紧缩的第一级，但这只贡献了将典型基因组装入间期核或一组中期染色体所需的紧缩的相对较小的一部分，这表明存在额外的“更高阶”的染色质紧缩水平。确定这些水平、它们的相互关系以及控制它们发生的原则一直是一个具有挑战性且备受讨论的问题。在本文中，我们重点介绍了最近的实验进展和新兴证据，这些证据表明结构可塑性和染色质动力学在基因组组织中发挥主导作用。我们还讨论了可能在不久的将来产生重要见解的新方法，并提出了值得进一步研究的研究领域。
