H-NS mediated compaction of DNA visualised by atomic force microscopy.
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.
Dame
R T
RT
Laboratory of Molecular Genetics, Gorlaeus Laboratories, Leiden Institute of Chemistry, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands.
Wyman
C
C
Goosen
N
N
D001426:Bacterial Proteins / Q000378:metabolism / Q000502:physiology* / Q000648:ultrastructure; D004247:DNA / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure*; D004268:DNA-Binding Proteins / Q000378:metabolism / Q000502:physiology* / Q000648:ultrastructure; D004926:Escherichia coli; D018625:Microscopy, Atomic Force; D009690:Nucleic Acid Conformation; D011485:Protein Binding; D011487:Protein Conformation
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; C031908:H-NS protein, bacteria; D004247:DNA