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Replication of vertebrate mitochondrial DNA entails transient ribonucleotide incorporation throughout the lagging strand.

ABSTRACT: Using two-dimensional agarose gel electrophoresis, we show that mitochondrial DNA (mtDNA) replication of birds and mammals frequently entails ribonucleotide incorporation throughout the lagging strand (RITOLS). Based on a combination of two-dimensional agarose gel electrophoretic analysis and mapping of 5' ends of DNA, initiation of RITOLS replication occurs in the major non-coding region of vertebrate mtDNA and is effectively unidirectional. In some cases, conversion of nascent RNA strands to DNA starts at defined loci, the most prominent of which maps, in mammalian mtDNA, in the vicinity of the site known as the light-strand origin.

SUBMITTER: Yasukawa T

PROVIDER: S-EPMC1636616 | biostudies-literature | 2006 Nov

REPOSITORIES: biostudies-literature

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Replication of vertebrate mitochondrial DNA entails transient ribonucleotide incorporation throughout the lagging strand.

Yasukawa Takehiro T Reyes Aurelio A Cluett Tricia J TJ Yang Ming-Yao MY Bowmaker Mark M Jacobs Howard T HT Holt Ian J IJ

The EMBO journal 20061026 22

Using two-dimensional agarose gel electrophoresis, we show that mitochondrial DNA (mtDNA) replication of birds and mammals frequently entails ribonucleotide incorporation throughout the lagging strand (RITOLS). Based on a combination of two-dimensional agarose gel electrophoretic analysis and mapping of 5' ends of DNA, initiation of RITOLS replication occurs in the major non-coding region of vertebrate mtDNA and is effectively unidirectional. In some cases, conversion of nascent RNA strands to D ...[more]

PMID: 17066082

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