title: Involvement of mitochondrial-targeted RecA in the repair of mitochondrial DNA in the moss, Physcomitrella patens.
abstract: Homologous recombination is a universal process that contributes to genetic diversity and genomic integrity. Bacterial-type RecA generally exists in all bacteria and plays a crucial role in homologous recombination. Although RecA homologues also exist in plant mitochondria, there have been few reports about the in vivo functions of these homologues. We identified a recA gene orthologue (named PprecA1) in a cDNA library of the moss, Physcomitrella patens. N-terminal fusion of the putative organellar targeting sequence of PpRecA1 to GFP caused a targeting of PpRecA1 to mitochondria. PprecA1 partially complemented the effects of a DNA damaging agent in an Escherichia coli recA deficient strain. Additionally, the expression of PprecA1 was induced by treating the plants with DNA damaging agents. Disruption of PprecA1 by targeted replacement resulted lower rate of the recovery of the mitochondrial DNA from methyl methan sulfonate damage. This is the first report about the characteristics of a null mutant of bacterial-type recA gene in plant. The data suggest that PprecA1 participates in the repair of mitochondrial DNA in P. patens.
authors: Department of Life Science, College of Science, Rikkyo, St. Paul's University, Tokyo, Japan.
authors: Masaki
authors: M
authors: Odahara
authors: Takayuki
authors: T
authors: Inouye
authors: Tomomichi
authors: T
authors: Fujita
authors: Mitsuyasu
authors: M
authors: Hasebe
authors: Yasuhiko
authors: Y
authors: Sekine
mesh_terms: D000595:Amino Acid Sequence; D019068:Bryopsida / Q000201:enzymology* / Q000235:genetics; D004260:DNA Repair; D004272:DNA, Mitochondrial / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D008928:Mitochondria / Q000201:enzymology*; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010802:Phylogeny; D010940:Plant Proteins / Q000032:analysis / Q000378:metabolism*; D011938:Rec A Recombinases / Q000032:analysis / Q000378:metabolism*; D011995:Recombination, Genetic; D016415:Sequence Alignment; D013997:Time Factors
chemical_list: D004272:DNA, Mitochondrial; D010940:Plant Proteins; D011938:Rec A Recombinases