Luger Karolin, Hansen Jeffrey C
Department of Biochemistry and Molecular Biology, Colorado State University,Mail Code 1870, Fort Collins, CO 80523, USA.
Curr Opin Struct Biol. 2005 Apr;15(2):188-96. doi: 10.1016/j.sbi.2005.03.006.
Chromosomal DNA is packaged into condensed nucleoprotein suprastructures, yet the DNA can be accessed as needed within this structural context. Recently, progress has been made concerning how the nucleosomal subunits of chromatin fibers are disassembled and reassembled in vitro and in vivo. At the level of the chromatin fiber, the conformational organization of condensed 30 nm secondary structures has been elucidated. A great deal of progress also has been made toward understanding how chromatin architectural proteins, such as MeCP2, MENT, polycomb and HP1alpha, assemble different specific types of secondary and tertiary chromatin structures. The emerging picture is that the inherent dynamics of nucleosomal assemblages at all structural levels are a key link between the condensed domains found in eukaryotic genomes and the functions that take place within them.
染色体DNA被包装成浓缩的核蛋白超结构，但在这种结构背景下，DNA可根据需要被访问。最近，在染色质纤维的核小体亚基如何在体外和体内进行拆卸和重新组装方面取得了进展。在染色质纤维水平上，已阐明了浓缩的30 nm二级结构的构象组织。在理解染色质结构蛋白，如MeCP2、MENT、多梳蛋白和HP1α如何组装不同特定类型的二级和三级染色质结构方面也取得了很大进展。新出现的情况是，在所有结构水平上核小体组装体的固有动力学是真核基因组中发现的浓缩结构域与其内部发生的功能之间的关键联系。
