Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin, Dublin 2, Ireland.
BMC Mol Cell Biol. 2019 Jul 18;20(1):26. doi: 10.1186/s12860-019-0211-6.
The processes of DNA supercoiling and transcription are interdependent because the movement of a transcription elongation complex simultaneously induces under- and overwinding of the DNA duplex and because the initiation, elongation and termination steps of transcription are all sensitive to the topological state of the DNA.
Policing of the local and global supercoiling of DNA by topoisomerases helps to sustain the major DNA-based transactions by eliminating barriers to the movement of transcription complexes and replisomes. Recent data from whole-genome and single-molecule studies have provided new insights into how interactions between transcription and the supercoiling of DNA influence the architecture of the chromosome and how they create cell-to-cell diversity at the level of gene expression through transcription bursting.
These insights into fundamental molecular processes reveal mechanisms by which bacteria can prevail in unpredictable and often hostile environments by becoming unpredictable themselves.
DNA 超螺旋化和转录过程是相互依存的，因为转录延伸复合物的移动同时诱导 DNA 双链的欠超螺旋和过超螺旋，并且转录的起始、延伸和终止步骤都对 DNA 的拓扑状态敏感。
拓扑异构酶对 DNA 局部和整体超螺旋的监管有助于通过消除转录复合物和复制体运动的障碍来维持主要的基于 DNA 的交易。来自全基因组和单分子研究的最新数据提供了新的见解，即转录和 DNA 超螺旋之间的相互作用如何影响染色体的结构，以及它们如何通过转录爆发在基因表达水平上产生细胞间多样性。
这些对基本分子过程的深入了解揭示了细菌如何通过自身的不可预测性在不可预测且常常充满敌意的环境中生存的机制。
