Characterization of a high-affinity binding site for a DNA-binding protein from sea urchin embryo mitochondria.
Based on electrophoretic mobility shift assays, DNase I footprinting and modification interference analyses we have identified a sequence-specific DNA-binding protein in blastula stage mitochondria of the sea urchin Strongylocentrotus purpuratus, which interacts with a binding site around the major pause site for DNA replication. This region straddles the boundary of the genes for ATP synthase subunit 6 and cytochrome c oxidase subunit III, and contains also a prominent origin of lagging-strand synthesis. The protein is thermostable, and its natural high-affinity binding site comprises the sequence 5'-AGCCT(N7)AGCAT-3'. Binding studies have demonstrated that two copies of the imperfect repeat, as well as the 7 bp spacing between them, are essential for tight binding. Based on the location of its binding site, we tentatively designate the protein mitochondrial pause-region binding protein (mtPBP) 1.
Qureshi
S A
SA
Robertson Institute of Biotechnology, Department of Genetics, University of Glasgow, UK.
Jacobs
H T
HT
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D001755:Blastocyst / Q000737:chemistry; D004261:DNA Replication / Q000502:physiology; D004272:DNA, Mitochondrial / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D003576:Electron Transport Complex IV / Q000235:genetics*; D008745:Methylation; D008928:Mitochondria / Q000737:chemistry; D008969:Molecular Sequence Data; D006180:Proton-Translocating ATPases / Q000235:genetics*; D012617:Sea Urchins / Q000737:chemistry* / Q000196:embryology
D004272:DNA, Mitochondrial; D004268:DNA-Binding Proteins; D003576:Electron Transport Complex IV; D006180:Proton-Translocating ATPases