title: Unusual DNA structures at the integration site of an HIV provirus.
abstract: Supercoiled pHXBc2 DNA (containing the genome of the human immunodeficiency virus type 1 and human sequences) migrated more slowly than linear DNA in native and ethidium bromide agarose gel electrophoresis at 4.5 volts/cm, suggesting the presence of unusual DNA structures. S1 nuclease analysis of pHXBc2 revealed two S1 hypersensitive sites. Site I was located within a 25 bp direct repeat in host DNA 0.6 kB upstream from the 5' LTR. Site II was mapped 0.2 kB upstream from the vif gene start site. Sequence analysis showed that Site I sequences could assume different unusual DNA structures, whereas sequences at Site II could assume either slipped or H-DNA forms. Unusual DNA structures in host DNA may be associated with active chromatin regions and may favor proviral integration.
authors.affiliation: Division of Cancer Pharmacology, Dana-Farber Cancer Institute, Boston, MA.
authors.forename: M A
authors.initials: MA
authors.lastname: Gama Sosa
authors.forename: J C
authors.initials: JC
authors.lastname: Hall
authors.forename: K E
authors.initials: KE
authors.lastname: Schneider
authors.forename: G C
authors.initials: GC
authors.lastname: Lukaszewicz
authors.forename: R M
authors.initials: RM
authors.lastname: Ruprecht
mesh_terms: D001483:Base Sequence; D004252:DNA Mutational Analysis; D004251:DNA Transposable Elements; D004278:DNA, Superhelical; D004587:Electrophoresis, Agar Gel; D004720:Endonucleases; D005814:Genes, Viral; D015497:HIV-1 / Q000235:genetics*; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D011533:Proviruses / Q000235:genetics*; D015719:Single-Strand Specific DNA and RNA Endonucleases
chemical_list: D004251:DNA Transposable Elements; D004278:DNA, Superhelical; D004720:Endonucleases; D015719:Single-Strand Specific DNA and RNA Endonucleases