AtSPO11-1 is necessary for efficient meiotic recombination in plants.
The Saccharomyces cerevisiae Spo11 protein catalyses DNA double-strand breaks (DSBs) that initiate meiotic recombination. The model plant Arabidopsis thaliana possesses at least three SPO11 homologues. T-DNA and ethyl-methane sulfonate mutagenesis allowed us to show that meiotic progression is altered in plants in which the AtSPO11-1 gene is disrupted. Both male and female meiocytes formed very few bivalents. Furthermore, no fully synapsed chromosomes were observed during prophase I. Later, in meiosis I, we observed that chromosomes segregated randomly, leading to the production of a large proportion of non-functional gametes. These meiotic aberrations were associated with a drastic reduction in meiotic recombination. Thus, our data show that initiation of meiotic recombination by SPO11- induced DSBs is a mechanism conserved in plants. Furthermore, unlike Drosophila and Caenorhabditis elegans, but like fungi, SPO11 is necessary for normal synapsis in plants.
Grelon
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Station de Génétique et d'Amélioration des Plantes, INRA de Versailles, Route de St-Cyr, 78026 Versailles Cedex, France. grelon@versailles.inra.fr
Vezon
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Gendrot
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Pelletier
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D000595:Amino Acid Sequence; D000818:Animals; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics*; D001483:Base Sequence; D017931:DNA Primers / Q000235:genetics; D004706:Endodeoxyribonucleases; D004950:Esterases / Q000235:genetics* / Q000502:physiology*; D017343:Genes, Plant; D008540:Meiosis / Q000235:genetics*; D008969:Molecular Sequence Data; D009154:Mutation; D011995:Recombination, Genetic; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D000099257:Meiotic Recombination Protein SPO11
D017931:DNA Primers; D004706:Endodeoxyribonucleases; D004950:Esterases; D000099257:Meiotic Recombination Protein SPO11