Ctp1CtIP and Rad32Mre11 nuclease activity are required for Rec12Spo11 removal, but Rec12Spo11 removal is dispensable for other MRN-dependent meiotic functions.
The evolutionarily conserved Mre11/Rad50/Nbs1 (MRN) complex is involved in various aspects of meiosis. Whereas available evidence suggests that the Mre11 nuclease activity might be responsible for Spo11 removal in Saccharomyces cerevisiae, this has not been confirmed experimentally. This study demonstrates for the first time that Mre11 (Schizosaccharomyces pombe Rad32(Mre11)) nuclease activity is required for the removal of Rec12(Spo11). Furthermore, we show that the CtIP homologue Ctp1 is required for Rec12(Spo11) removal, confirming functional conservation between Ctp1(CtIP) and the more distantly related Sae2 protein from Saccharomyces cerevisiae. Finally, we show that the MRN complex is required for meiotic recombination, chromatin remodeling at the ade6-M26 recombination hot spot, and formation of linear elements (which are the equivalent of the synaptonemal complex found in other eukaryotes) but that all of these functions are proficient in a rad50S mutant, which is deficient for Rec12(Spo11) removal. These observations suggest that the conserved role of the MRN complex in these meiotic functions is independent of Rec12(Spo11) removal.
Hartsuiker
Edgar
E
Genome Damage and Stability Centre, Sussex University, Brighton BN15 8HG, United Kingdom. E.Hartsuiker@sussex.ac.uk
Mizuno
Kenichi
K
Molnar
Monika
M
Kohli
Juerg
J
Ohta
Kunihiro
K
Carr
Antony M
AM
D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism; D053903:DNA Breaks, Double-Stranded; D004260:DNA Repair; D004271:DNA, Fungal / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004706:Endodeoxyribonucleases; D004950:Esterases / Q000378:metabolism; D005090:Exodeoxyribonucleases / Q000378:metabolism*; D017353:Gene Deletion; D005799:Genes, Dominant; D008540:Meiosis; D009707:Nucleosomes / Q000378:metabolism; D010641:Phenotype; D011995:Recombination, Genetic; D012568:Schizosaccharomyces / Q000166:cytology* / Q000201:enzymology*; D029702:Schizosaccharomyces pombe Proteins / Q000378:metabolism*; D013172:Spores, Fungal / Q000166:cytology / Q000378:metabolism; D013696:Temperature; D000099257:Meiotic Recombination Protein SPO11
D002868:Chromosomal Proteins, Non-Histone; D004271:DNA, Fungal; D004268:DNA-Binding Proteins; D004706:Endodeoxyribonucleases; D004950:Esterases; D005090:Exodeoxyribonucleases; D009707:Nucleosomes; D029702:Schizosaccharomyces pombe Proteins; D000099257:Meiotic Recombination Protein SPO11; C525888:Ctp1 protein, S pombe; C478035:Nbs1 protein, S pombe; C480032:Rad50 protein, S pombe; C456270:rec12 protein, S pombe; C092453:Mre11 protein, S pombe