title: The resolving enzyme CCE1 of yeast opens the structure of the four-way DNA junction.
abstract: Junction-resolving enzymes exhibit structure-selective binding to DNA, but may also manipulate the DNA structure. CCE1 is a junction-resolving enzyme found in the yeast mitochondrion. To facilitate the analysis of the CCE1-junction interaction, we have exploited the sequence dependence of the cleavage reaction to devise a junction that is refractory to cleavage by this enzyme, even in the presence of magnesium ions. On binding to four-way DNA junctions, pure recombinant CCE1 opens the global structure into a 4-fold symmetrical configuration of arms with an open, chemically reactive centre. The structure of the CCE1-junction complex is independent of the sequence of the junction, and of the presence or absence of magnesium or other ions. This and other functional properties of CCE1 are strikingly similar to those of RuvC resolving enzyme of Escherichia coli.
authors.affiliation: Department of Biochemistry, University Dundee, UK.
authors.forename: M F
authors.initials: MF
authors.lastname: White
authors.forename: D M
authors.initials: DM
authors.lastname: Lilley
mesh_terms: D001483:Base Sequence; D004247:DNA / Q000737:chemistry* / Q000378:metabolism*; D004254:DNA Nucleotidyltransferases / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism; D004706:Endodeoxyribonucleases / Q000378:metabolism*; D045565:Holliday Junction Resolvases; D007700:Kinetics; D008928:Mitochondria / Q000201:enzymology; D008961:Models, Structural; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D011487:Protein Conformation; D012441:Saccharomyces cerevisiae / Q000201:enzymology*; D029701:Saccharomyces cerevisiae Proteins; D013379:Substrate Specificity; D019895:Transposases
chemical_list: D004268:DNA-Binding Proteins; D009838:Oligodeoxyribonucleotides; D029701:Saccharomyces cerevisiae Proteins; D004247:DNA; D004254:DNA Nucleotidyltransferases; D019895:Transposases; D004706:Endodeoxyribonucleases; C473486:CCE1 protein, S cerevisiae; D045565:Holliday Junction Resolvases