Dame R T, Wyman C, Goosen N
Laboratory of Molecular Genetics, Gorlaeus Laboratories, Leiden Institute of Chemistry, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands.
Nucleic Acids Res. 2000 Sep 15;28(18):3504-10. doi: 10.1093/nar/28.18.3504.
The Escherichia coli H-NS protein is a nucleoid-associated protein involved in gene regulation and DNA compaction. To get more insight into the mechanism of DNA compaction we applied atomic force microscopy (AFM) to study the structure of H-NS-DNA complexes. On circular DNA molecules two different levels of H-NS induced condensation were observed. H-NS induced lateral condensation of large regions of the plasmid. In addition, large globular structures were identified that incorporated a considerable amount of DNA. The formation of these globular structures appeared not to be dependent on any specific sequence. On the basis of the AFM images, a model for global condensation of the chromosomal DNA by H-NS is proposed.
大肠杆菌H-NS蛋白是一种与类核相关的蛋白质，参与基因调控和DNA压缩。为了更深入了解DNA压缩机制，我们应用原子力显微镜（AFM）研究H-NS-DNA复合物的结构。在环状DNA分子上，观察到H-NS诱导的两种不同程度的凝聚。H-NS诱导质粒大片段区域的侧向凝聚。此外，还鉴定出包含大量DNA的大球状结构。这些球状结构的形成似乎不依赖于任何特定序列。基于AFM图像，提出了一个H-NS介导染色体DNA全局凝聚的模型。
