《生命科学》 2017, 29(10): 955-967
摘 要：摘 要：真核生物中，DNA 作为遗传物质并不是裸露存在的，而是以染色质的形式存储在细胞核中。作为遗传信息的载体，长达数米的基因组DNA 被压缩在微米级的细胞核中却能精确地控制生物高度有序的各种生理活动，因此，染色质的空间结构必定具有一定的规律性且高度可控。而30 nm 染色质纤维作为从核小体串珠结构到高级染色质结构中间一个关键的结构阶段，在诸多DNA 相关的生命活动中起重要调控功能，因此，对其结构及动态调控相关的研究具有重要的生物学意义。现总结近年来30 nm 染色质纤维精细结构解析以及染色质结构动态调控方面的一些重要最新进展，同时，也对细胞核内染色质纤维结构的一些基因组学和电镜方面的最新研究进行了讨论和展望。
Abstract: Abstract: Genomic DNA in eukaryote is hierarchically packaged by histones into chromatin to fit inside the nucleus. As the carrier of genetic information， genomic DNA， as long as 2 meters， can precisely fulfill and regulate all DNA-related biological processes while they’re compacted into chromatin within nucleus of a few micrometers. Therefore， the ultrastructure and 3D organization of chromatin fibers must be regular and regulatable as well. As a central-level structure between nucleosomal arrays and higher-order chromatin organizations， the 30-nm chromatin fiber and its dynamics play a crucial role in gene regulation. Here， we mainly review the most recent progresses in elucidating the structure of 30-nm chromatin fiber in vitro and epigenetic regulation of chromatin fibers by chromatin factors. In addition， we also discuss recent studies in unraveling the 3D organization of chromatin fibers in situ by genomic approaches and electron microscopy.
