The Arabidopsis thaliana MND1 homologue plays a key role in meiotic homologous pairing, synapsis and recombination.
Mnd1 has recently been identified in yeast as a key player in meiotic recombination. Here we describe the identification and functional characterisation of the Arabidopsis homologue, AtMND1, which is essential for male and female meiosis and thus for plant fertility. Although axial elements are formed normally, sister chromatid cohesion is established and recombination initiation appears to be unaffected in mutant plants, chromosomes do not synapse. During meiotic progression, a mass of entangled chromosomes, interconnected by chromatin bridges, and severe chromosome fragmentation are observed. These defects depend on the presence of SPO11-1, a protein that initiates recombination by catalysing DNA double-strand break (DSB) formation. Furthermore, we demonstrate that the AtMND1 protein interacts with AHP2, the Arabidopsis protein closely related to budding yeast Hop2. These data demonstrate that AtMND1 plays a key role in homologous synapsis and in DSB repair during meiotic recombination.
Kerzendorfer
Claudia
C
Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, A-1030 Vienna, Austria.
Vignard
Julien
J
Pedrosa-Harand
Andrea
A
Siwiec
Tanja
T
Akimcheva
Svetlana
S
Jolivet
Sylvie
S
Sablowski
Robert
R
Armstrong
Susan
S
Schweizer
Dieter
D
Mercier
Rapheal
R
Schlögelhofer
Peter
P
D017360:Arabidopsis / Q000235:genetics* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000502:physiology*; D023902:Chromosome Pairing / Q000235:genetics / Q000502:physiology*; D004249:DNA Damage; D008540:Meiosis / Q000502:physiology*; D009154:Mutation; D011995:Recombination, Genetic; D000099257:Meiotic Recombination Protein SPO11
D029681:Arabidopsis Proteins; C514180:MND1 protein, Arabidopsis; C477460:Spo11-1 protein, Arabidopsis; D000099257:Meiotic Recombination Protein SPO11