The banana (Musa acuminata) genome and the evolution of monocotyledonous plants.
Angélique D’Hont, France Denoeud, Jean-Marc Aury, Franc-Christophe Baurens, Françoise Carreel, Olivier Garsmeur, Benjamin Noel, Stéphanie Bocs, Gaëtan Droc, Mathieu Rouard, Corinne Da Silva, Kamel Jabbari, Céline Cardi, Julie Poulain, Marlène Souquet, Karine Labadie, Cyril Jourda, Juliette Lengellé, Marguerite Rodier-Goud, Adriana Alberti, Maria Bernard, Margot Correa, Saravanaraj Ayyampalayam, Michael R. Mckain, Jim Leebens-Mack, Diane Burgess, Mike Freeling, Didier Mbéguié-A-Mbéguié, Matthieu Chabannes, Thomas Wicker, Olivier Panaud, Jose Barbosa, Eva Hribova, Pat Heslop-Harrison, Rémy Habas, Ronan Rivallan, Philippe Francois, Claire Poiron, Andrzej Kilian, Dheema Burthia, Christophe Jenny, Frédéric Bakry, Spencer Brown, Valentin Guignon, Gert Kema, Miguel Dita, Cees Waalwijk, Steeve Joseph, Anne Dievart, Olivier Jaillon, Julie Leclercq, Xavier Argout, Eric Lyons, Ana Almeida, Mouna Jeridi, Jaroslav Dolezel, Nicolas Roux, Ange-Marie Risterucci, Jean Weissenbach, Manuel Ruiz, Jean-Christophe Glaszmann, Francis Quétier, Nabila Yahiaoui & Patrick Wincker
Bananas (Musa spp.), including dessert and cooking types, are giant perennial monocotyledonous herbs of the order Zingiberales, a sister group to the well-studied Poales, which include cereals. Bananas are vital for food security in many tropical and subtropical countries and the most popular fruit in industrialized countries. The Musa domestication process started some 7,000 years ago in Southeast Asia. It involved hybridizations between diverse species and subspecies, fostered by human migrations, and selection of diploid and triploid seedless, parthenocarpic hybrids thereafter widely dispersed by vegetative propagation. Half of the current production relies on somaclones derived from a single triploid genotype (Cavendish). Pests and diseases have gradually become adapted, representing an imminent danger for global banana production. Here we describe the draft sequence of the 523-megabase genome of a Musa acuminata doubled-haploid genotype, providing a crucial stepping-stone for genetic improvement of banana. We detected three rounds of whole-genome duplications in the Musa lineage, independently of those previously described in the Poales lineage and the one we detected in the Arecales lineage. This first monocotyledon high-continuity whole-genome sequence reported outside Poales represents an essential bridge for comparative genome analysis in plants. As such, it clarifies commelinid-monocotyledon phylogenetic relationships, reveals Poaceae-specific features and has led to the discovery of conserved non-coding sequences predating monocotyledon–eudicotyledon divergence.
The unpeeling of the banana genome announced in Nature
The publication in the journal Nature of the sequence of one of the founding genomes of the banana, a subspecies of Musa acuminata, represents a major achievement for CIRAD and Genoscope, who led the sequencing project funded by the French government. It also opens up a new era for Musa scientists interested in harnessing the power of genomics to secure the future of this important crop.
According to the Nature paper, to which collaborated several scientific teams, including members of the Global Musa Genomics Consortium, 91% of the genome has been sequenced and 92% of the predicted 36,542 genes positioned on the chromosomes. The article goes on to analyse the evolutionary relationships between the banana and the other monocots whose genome has been sequenced. It also reveals that the banana lineage has undergone three rounds of whole genome duplication during the course of its evolution.
The availability of a high-quality reference sequence is an important milestone for the Consortium, whose first objective at the time of its creation was to ensure that the scientific community would have access to a complete sequence of the Musa genome.
http://www.musagenomics.org/
a, Paralogous relationships between chromosome segments from Musa α/β ancestral blocks 2 (red) and 8 (green). The 12 Musa α/β ancestral blocks are shown in different colours on the circle. b, Orthologous relationships of Musa ancestral blocks 2 and 8 with rice ancestral blocks ρ2, ρ5 and σ6. We did not observe a one-to-one relationship between, for instance, Musa α/β ancestral block 2 and one ρ ancestral block, which suggests that the γ and σ duplications are two separate events. c, Representation of the deduced WGD event.
