Random chromosome segregation without meiotic arrest in both male and female meiocytes of a dmc1 mutant of Arabidopsis.
In yeast, the DMC1 gene is required for interhomolog recombination, which is an essential step for bivalent formation and the correct partition of chromosomes during meiosis I. By using a reverse genetics approach, we were able to identify a T-DNA insertion in AtDMC1, the Arabidopsis homolog of DMC1. Homozygotes for the AtDMC1 insertion failed to express AtDMC1, and their residual fertility was 1.5% that of the wild type. Complete fertility was restored in mutant plants when a wild-type copy of the AtDMC1 gene was reintroduced. Cytogenetical analysis points to a correlation of the sterility phenotype with severely disturbed chromosome behavior during both male and female meiosis. In this study, our data demonstrate that AtDMC1 function is crucial for meiosis in Arabidopsis. However, meiosis can be completed in the Arabidopsis dmc1 mutant, which is not the case for mouse or some yeast mutants.
Couteau
F
F
Institut de Biotechnologie des Plantes, Bâtiment 630, Université Paris-Sud, 91405 Orsay, France. florence.couteau@ibp.u-psud.fr
Belzile
F
F
Horlow
C
C
Grandjean
O
O
Vezon
D
D
Doutriaux
M P
MP
D000251:Adenosine Triphosphatases; D000818:Animals; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins; D001483:Base Sequence; D018797:Cell Cycle Proteins; D002875:Chromosomes / Q000235:genetics; D017931:DNA Primers / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics; D017343:Genes, Plant; D005816:Genetic Complementation Test; D008540:Meiosis / Q000235:genetics*; D051379:Mice; D016254:Mutagenesis, Insertional; D009154:Mutation; D009687:Nuclear Proteins; D010641:Phenotype; D028044:Phosphate-Binding Proteins; D010940:Plant Proteins / Q000235:genetics; D011938:Rec A Recombinases
D029681:Arabidopsis Proteins; D018797:Cell Cycle Proteins; D017931:DNA Primers; D004268:DNA-Binding Proteins; C513032:Dmc1 protein, mouse; D009687:Nuclear Proteins; D028044:Phosphate-Binding Proteins; D010940:Plant Proteins; C513034:ATDMC1 protein, Arabidopsis; D011938:Rec A Recombinases; D000251:Adenosine Triphosphatases