Structural and functional partitioning
of bread wheat chromosome 3B

Frédéric Choulet, Adriana Alberti, Sébastien Theil, Natasha Glover, Valérie Barbe, Josquin Daron, Lise Pingault, Pierre Sourdille, Arnaud Couloux, Etienne Paux, Philippe Leroy, Sophie Mangenot, Nicolas Guilhot, Jacques Le Gouis, Francois Balfourier, Michael Alaux, Véronique Jamilloux, Julie Poulain, Céline Durand, Arnaud Bellec, Christine Gaspin, Jan Safar, Jaroslav Dolezel, Jane Rogers, Klaas Vandepoele, Jean-Marc Aury, Klaus Mayer, Hélène Berges, Hadi Quesneville, Patrick Wincker, Catherine Feuillet

We produced a reference sequence of the 1-gigabase chromosome 3B of hexaploid bread wheat. By sequencing 8452 bacterial artificial chromosomes in pools, we assembled a sequence of 774 megabases carrying 5326 protein-coding genes, 1938 pseudogenes, and 85% of transposable elements. The distribution of structural and functional features along the chromosome revealed partitioning correlated with meiotic recombination. Comparative analyses indicated high wheat-specific inter- and intrachromosomal gene duplication activities that are potential sources of variability
for adaption. In addition to providing a better understanding of the organization, function, and evolution of a large and polyploid genome, the availability of a high-quality sequence anchored to genetic maps will accelerate the identification of genes underlying important agronomic traits.