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Mechanism of homologous recombination and implications for aging-related deletions in mitochondrial DNA.

ABSTRACT: Homologous recombination is a universal process, conserved from bacteriophage to human, which is important for the repair of double-strand DNA breaks. Recombination in mitochondrial DNA (mtDNA) was documented more than 4 decades ago, but the underlying molecular mechanism has remained elusive. Recent studies have revealed the presence of a Rad52-type recombination system of bacteriophage origin in mitochondria, which operates by a single-strand annealing mechanism independent of the canonical RecA/Rad51-type recombinases. Increasing evidence supports the notion that, like in bacteriophages, mtDNA inheritance is a coordinated interplay between recombination, repair, and replication. These findings could have profound implications for understanding the mechanism of mtDNA inheritance and the generation of mtDNA deletions in aging cells.

SUBMITTER: Chen XJ

PROVIDER: S-EPMC3811608 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Mechanism of homologous recombination and implications for aging-related deletions in mitochondrial DNA.

Chen Xin Jie XJ

Microbiology and molecular biology reviews : MMBR 20130901 3

Homologous recombination is a universal process, conserved from bacteriophage to human, which is important for the repair of double-strand DNA breaks. Recombination in mitochondrial DNA (mtDNA) was documented more than 4 decades ago, but the underlying molecular mechanism has remained elusive. Recent studies have revealed the presence of a Rad52-type recombination system of bacteriophage origin in mitochondria, which operates by a single-strand annealing mechanism independent of the canonical Re ...[more]

PMID: 24006472

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