Zhao Hui, Dean Ann
Laboratory of Cellular and Developmental Biology, NIDDK, NIH, Bethesda, MD 20892, USA.
Biochem Cell Biol. 2005 Aug;83(4):516-24. doi: 10.1139/o05-054.
Enhancers can activate their target genes over large linear distances. Insulators can delimit the influence of an enhancer to an appropriate target. There are a number of intertwined mechanisms by which the regulatory functions of enhancers and insulators might be carried out at the level of the chromatin fiber. Recent evidence suggests that both enhancers and insulators participate in higher-order organization of chromatin in the nucleus and in localization of their regulated sequences to both subnuclear structures and compartments. Novel experimental approaches are helping to reveal the mechanisms underlying nuclear organization of developmentally regulated genes.
增强子能够在较大的线性距离上激活其靶基因。绝缘子能够将增强子的影响限定在合适的靶标上。在染色质纤维水平上，增强子和绝缘子的调控功能可能通过多种相互交织的机制来实现。最近的证据表明，增强子和绝缘子都参与了细胞核中染色质的高级组织，以及它们所调控序列在亚核结构和区室中的定位。新的实验方法有助于揭示发育调控基因的核组织背后的机制。
