Migration of a Holliday junction through a nucleosome directed by the E. coli RuvAB motor protein.
Chromatin plays a critical role in regulating access to DNA by proteins that direct recombination and repair. The E. coli RuvAB protein complex promotes branch migration of the Holliday junction recombination intermediate. The ability of RuvAB to negotiate passage of the junction through nucleosomal DNA is examined. The model system involves the formation of a Holliday junction positioned upstream of a nucleosome. Unassisted, the junction is blocked by a histone octamer. In the presence of RuvAB and ATP, rapid branch migration through the nucleosome is observed. It results in disruption of the histone-DNA interactions leading to the removal of the octamer from the junction intermediate. These results suggest that eukaryotic DNA motor proteins analogous to RuvAB could function during recombination to promote branch migration through chromatin.
Genetics and Biochemistry Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-1810, USA.
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M
Grigoriev
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P
Hsieh
D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D001483:Base Sequence; D004265:DNA Helicases / Q000378:metabolism*; D004260:DNA Repair; D004269:DNA, Bacterial / Q000737:chemistry / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins; D006657:Histones / Q000378:metabolism; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D009692:Nucleic Acid Heteroduplexes / Q000737:chemistry / Q000378:metabolism; D009707:Nucleosomes / Q000378:metabolism*; D011487:Protein Conformation; D011995:Recombination, Genetic
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D006657:Histones; D009692:Nucleic Acid Heteroduplexes; D009707:Nucleosomes; C061260:RuvB protein, Bacteria; C071059:Holliday junction DNA helicase, E coli; D004265:DNA Helicases