Department of Pharmacology, UMDNJ-Robert Wood Johnson Medical School, Piscataway, New Jersey, USA.
Mol Cell Biol. 2012 Dec;32(24):4892-7. doi: 10.1128/MCB.01127-12. Epub 2012 Oct 8.
Enhancers are regulatory DNA sequences that activate transcription over long distances. Recent studies revealed a widespread role of distant activation in eukaryotic gene regulation and in development of various human diseases, including cancer. Genomic and gene-targeted studies of enhancer action revealed novel mechanisms of transcriptional activation over a distance. They include formation of stable, inactive DNA-protein complexes at the enhancer and target promoter before activation, facilitated distant communication by looping of the spacer chromatin-covered DNA, and promoter activation by mechanisms that are different from classic recruiting. These studies suggest the similarity between the looping mechanisms involved in enhancer action on DNA in bacteria and in chromatin of higher organisms.
增强子是一种调节 DNA 序列，可以远距离激活转录。最近的研究揭示了远距离激活在真核生物基因调控和各种人类疾病（包括癌症）发展中的广泛作用。对增强子作用的基因组和基因靶向研究揭示了远距离转录激活的新机制。它们包括在激活前在增强子和靶启动子处形成稳定的、无活性的 DNA-蛋白质复合物，通过间隔染色质覆盖的 DNA 的环化促进远距离通信，以及通过不同于经典招募的机制激活启动子。这些研究表明，细菌中 DNA 上增强子作用涉及的环化机制与高等生物染色质中的环化机制相似。
