title: A cruciform structural transition provides a molecular switch for chromosome structure and dynamics.
abstract: The interaction between specific sites along a DNA molecule is often crucial for the regulation of genetic processes. However, mechanisms regulating the interaction of specific sites are unknown. We have used atomic force microscopy to demonstrate that the structural transition between cruciform conformations can act as a molecular switch to facilitate or prevent communication between distant regions in DNA. Cruciform structures exist in vivo and they are critically involved in the initiation of replication and the regulation of gene expression in different organisms. Therefore, structural transitions of the cruciform may play a key role in these processes.
authors.affiliation: Department of Microbiology, Arizona State University, Tempe, AZ 85287-2701, USA.
authors.forename: L S
authors.initials: LS
authors.lastname: Shlyakhtenko
authors.forename: P
authors.initials: P
authors.lastname: Hsieh
authors.forename: M
authors.initials: M
authors.lastname: Grigoriev
authors.forename: V N
authors.initials: VN
authors.lastname: Potaman
authors.forename: R R
authors.initials: RR
authors.lastname: Sinden
authors.forename: Y L
authors.initials: YL
authors.lastname: Lyubchenko
mesh_terms: D020029:Base Pairing / Q000235:genetics; D002875:Chromosomes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D004265:DNA Helicases; D004278:DNA, Superhelical / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology; D029968:Escherichia coli Proteins; D018625:Microscopy, Atomic Force; D008957:Models, Genetic; D009690:Nucleic Acid Conformation; D010957:Plasmids / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D004278:DNA, Superhelical; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; C071059:Holliday junction DNA helicase, E coli; D004265:DNA Helicases