Lu Q, Wallrath L L, Elgin S C
Department of Biology, Washington University, St. Louis, Missouri 63130.
J Cell Biochem. 1994 May;55(1):83-92. doi: 10.1002/jcb.240550110.
Recent genetic and biochemical studies have revealed critical information concerning the role of nucleosomes in eukaryotic gene regulation. Nucleosomes package DNA into a dynamic chromatin structure, and by assuming defined positions in chromatin, influence gene regulation. Nucleosomes can serve as repressors, presumably by blocking access to regulatory elements; consequently, the positions of nucleosomes relative to the location of cis-acting elements are critical. Some genes have a chromatin structure that is "preset," ready for activation, while others require "remodeling" for activation. Nucleosome positioning may be determined by multiple factors, including histone-DNA interactions, boundaries defined by DNA structure or protein binding, and higher-order chromatin structure.
最近的遗传学和生物化学研究揭示了有关核小体在真核基因调控中作用的关键信息。核小体将DNA包装成动态的染色质结构，并通过在染色质中占据特定位置来影响基因调控。核小体可能作为阻遏物，大概是通过阻止对调控元件的访问；因此，核小体相对于顺式作用元件位置的位置至关重要。一些基因具有“预设”的染色质结构，随时准备激活，而另一些基因则需要“重塑”才能激活。核小体定位可能由多种因素决定，包括组蛋白-DNA相互作用、由DNA结构或蛋白质结合定义的边界以及高阶染色质结构。
