Journal article

FANCM Limits Meiotic Crossovers

Wayne Crismani, Chloe Girard, Nicole Froger, Monica Pradillo, Juan Luis Santos, Liudmila Chelysheva, Gregory P Copenhaver, Christine Horlow, Raphael Mercier



The number of meiotic crossovers (COs) is tightly regulated within a narrow range, despite a large excess of molecular precursors. The factors that limit COs remain largely unknown. Here, using a genetic screen in Arabidopsis thaliana, we identified the highly conserved FANCM helicase, which is required for genome stability in humans and yeasts, as a major factor limiting meiotic CO formation. The fancm mutant has a threefold-increased CO frequency as compared to the wild type. These extra COs arise not from the pathway that accounts for most of the COs in wild type, but from an alternate, normally minor pathway. Thus, FANCM is a key factor imposing an upper limit on the number of meiotic CO..

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Awarded by EU-FP7 program

Awarded by NSF

Awarded by Direct For Biological Sciences

Funding Acknowledgements

R.M. and J.L.S. thank the EU-FP7 program (Meiosys-KBBE-2009-222883), and G. P. C. thanks the NSF (MCB-1121563) for financial support. We thank V. Borde, M. Grelon, C. Mezard, F. Nogue, A. Demuyt, and O. Loudet for critical reading of the manuscript and helpful discussions. A provisional patent application based on the work has been filed by INRA.