title: Unique features of DNA replication in mitochondria: a functional and evolutionary perspective.
abstract: Last year, we reported a new mechanism of DNA replication in mammals. It occurs inside mitochondria and entails the use of processed transcripts, termed bootlaces, which hybridize with the displaced parental strand as the replication fork advances. Here we discuss possible reasons why such an unusual mechanism of DNA replication might have evolved. The bootlace mechanism can minimize the occurrence and impact of single-strand breaks that would otherwise threaten genome stability. Furthermore, by providing an implicit mismatch recognition system, it should limit the occurrence of replication-dependent deletions and insertions, and defend against invading elements. Such a mechanism may also limit attempts to manipulate the mammalian mitochondrial genome.
authors.affiliation: MRC National Institute for Medical Research, London, UK.
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Holt
authors.forename: Howard T
authors.initials: HT
authors.lastname: Jacobs
mesh_terms: D000818:Animals; D005075:Biological Evolution; D053903:DNA Breaks, Double-Stranded; D053904:DNA Breaks, Single-Stranded; D004261:DNA Replication / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000096:biosynthesis* / Q000235:genetics; D042822:Genomic Instability / Q000235:genetics*; D006801:Humans; D008928:Mitochondria / Q000235:genetics*
chemical_list: D004272:DNA, Mitochondrial
keywords: DNA; double strand breaks; fragile sites; mitochondria; mitochondrial DNA; replication; single strand breaks