The first meiosis of resynthesized Brassica napus, a genome blender
Article first published online: 8 FEB 2010
© The Authors (2010). Journal compilation © New Phytologist Trust (2010)
Special Issue: Plant polyploidy
Volume 186, Issue 1, pages 102–112, April 2010
How to Cite
Szadkowski, E., Eber, F., Huteau, V., Lodé, M., Huneau, C., Belcram, H., Coriton, O., Manzanares-Dauleux, M. J., Delourme, R., King, G. J., Chalhoub, B., Jenczewski, E. and Chèvre, A.-M. (2010), The first meiosis of resynthesized Brassica napus, a genome blender. New Phytologist, 186: 102–112. doi: 10.1111/j.1469-8137.2010.03182.x
- Issue published online: 3 MAR 2010
- Article first published online: 8 FEB 2010
- Received date: 28 August 2009, Accepted date: 9 December 2009
- Brassica napus (oilseed rape);
- homoeologous recombination;
- synthetic hybrids
- •Polyploidy promotes the restructuring of merged genomes within initial generations of resynthesized Brassica napus, possibly caused by homoeologous recombination at meiosis. However, little is known about the impact of the first confrontation of two genomes at the first meiosis which could lead to genome exchanges in progeny. Here, we assessed the role of the first meiosis in the genome instability of synthetic B. napus.
- •We used three different newly resynthesized B. napus plants and established meiotic pairing frequencies for the A and C genomes. We genotyped the three corresponding progenies in a cross to a natural B. napus on the two homoeologous A1 and C1 chromosomes. Pairing at meiosis in a set of progenies with various rearrangements was scored.
- •Here, we confirmed that the very first meiosis of resynthesized plants of B. napus acts as a genome blender, with many of the meiotic-driven genetic changes transmitted to the progenies, in proportions that depend significantly on the cytoplasm background inherited from the progenitors.
- •We conclude that the first meiosis generates rearrangements on both genomes and promotes subsequent restructuring in further generations. Our study advances the knowledge on the timing of genetic changes and the mechanisms that may bias their transmission.