Brca2 is involved in meiosis in Arabidopsis thaliana as suggested by its interaction with Dmc1.
Two BRCA2-like sequences are present in the Arabidopsis genome. Both genes are expressed in flower buds and encode nearly identical proteins, which contain four BRC motifs. In a yeast two-hybrid assay, the Arabidopsis Brca2 proteins interact with Rad51 and Dmc1. RNAi constructs aimed at silencing the BRCA2 genes at meiosis triggered a reproducible sterility phenotype, which was associated with dramatic meiosis alterations. We obtained the same phenotype upon introduction of RNAi constructs aimed at silencing the RAD51 gene at meiosis in dmc1 mutant plants. The meiotic figures we observed strongly suggest that homologous recombination is highly disturbed in these meiotic cells, leaving aberrant recombination events to repair the meiotic double-strand breaks. The 'brca2' meiotic phenotype was eliminated in spo11 mutant plants. Our experiments point to an essential role of Brca2 at meiosis in Arabidopsis. We also propose a role for Rad51 in the dmc1 context.
Siaud
Nicolas
N
Institut de Biotechnologie des Plantes, CNRS UMR8618, Université Paris XI, Orsay, France.
Dray
Eloïse
E
Gy
Isabelle
I
Gérard
Emmanuelle
E
Takvorian
Najat
N
Doutriaux
Marie-Pascale
MP
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000166:cytology* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins; D024682:BRCA2 Protein / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D018076:DNA, Complementary / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D035264:Flowers / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D020440:Gene Duplication; D020131:Genes, Duplicate / Q000235:genetics; D018745:Genome, Plant; D006801:Humans; D008540:Meiosis; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D010641:Phenotype; D030821:Plants, Genetically Modified; D011485:Protein Binding; D034622:RNA Interference; D051135:Rad51 Recombinase; D011938:Rec A Recombinases; D012441:Saccharomyces cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D016415:Sequence Alignment; D020798:Two-Hybrid System Techniques
D029681:Arabidopsis Proteins; D024682:BRCA2 Protein; D018797:Cell Cycle Proteins; C513033:DMC1 protein, S cerevisiae; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins; C513034:ATDMC1 protein, Arabidopsis; C495146:ATRAD51 protein, Arabidopsis; C495151:RAD51 protein, S cerevisiae; C495153:RAD51 protein, human; D051135:Rad51 Recombinase; D011938:Rec A Recombinases; C074556:DMC1 protein, human