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The Medicago genome provides insight into the evolution of rhizobial symbioses.

ABSTRACT: Legumes (Fabaceae or Leguminosae) are unique among cultivated plants for their ability to carry out endosymbiotic nitrogen fixation with rhizobial bacteria, a process that takes place in a specialized structure known as the nodule. Legumes belong to one of the two main groups of eurosids, the Fabidae, which includes most species capable of endosymbiotic nitrogen fixation. Legumes comprise several evolutionary lineages derived from a common ancestor 60 million years ago (Myr ago). Papilionoids are the largest clade, dating nearly to the origin of legumes and containing most cultivated species. Medicago truncatula is a long-established model for the study of legume biology. Here we describe the draft sequence of the M. truncatula euchromatin based on a recently completed BAC assembly supplemented with Illumina shotgun sequence, together capturing ?94% of all M. truncatula genes. A whole-genome duplication (WGD) approximately 58 Myr ago had a major role in shaping the M. truncatula genome and thereby contributed to the evolution of endosymbiotic nitrogen fixation. Subsequent to the WGD, the M. truncatula genome experienced higher levels of rearrangement than two other sequenced legumes, Glycine max and Lotus japonicus. M. truncatula is a close relative of alfalfa (Medicago sativa), a widely cultivated crop with limited genomics tools and complex autotetraploid genetics. As such, the M. truncatula genome sequence provides significant opportunities to expand alfalfa's genomic toolbox.

SUBMITTER: Young ND

PROVIDER: S-EPMC3272368 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature

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The Medicago genome provides insight into the evolution of rhizobial symbioses.

Young Nevin D ND Debellé Frédéric F Oldroyd Giles E D GE Geurts Rene R Cannon Steven B SB Udvardi Michael K MK Benedito Vagner A VA Mayer Klaus F X KF Gouzy Jérôme J Schoof Heiko H Van de Peer Yves Y Proost Sebastian S Cook Douglas R DR Meyers Blake C BC Spannagl Manuel M Cheung Foo F De Mita Stéphane S Krishnakumar Vivek V Gundlach Heidrun H Zhou Shiguo S Mudge Joann J Bharti Arvind K AK Murray Jeremy D JD Naoumkina Marina A MA Rosen Benjamin B Silverstein Kevin A T KA Tang Haibao H Rombauts Stephane S Zhao Patrick X PX Zhou Peng P Barbe Valérie V Bardou Philippe P Bechner Michael M Bellec Arnaud A Berger Anne A Bergès Hélène H Bidwell Shelby S Bisseling Ton T Choisne Nathalie N Couloux Arnaud A Denny Roxanne R Deshpande Shweta S Dai Xinbin X Doyle Jeff J JJ Dudez Anne-Marie AM Farmer Andrew D AD Fouteau Stéphanie S Franken Carolien C Gibelin Chrystel C Gish John J Goldstein Steven S González Alvaro J AJ Green Pamela J PJ Hallab Asis A Hartog Marijke M Hua Axin A Humphray Sean J SJ Jeong Dong-Hoon DH Jing Yi Y Jöcker Anika A Kenton Steve M SM Kim Dong-Jin DJ Klee Kathrin K Lai Hongshing H Lang Chunting C Lin Shaoping S Macmil Simone L SL Magdelenat Ghislaine G Matthews Lucy L McCorrison Jamison J Monaghan Erin L EL Mun Jeong-Hwan JH Najar Fares Z FZ Nicholson Christine C Noirot Céline C O'Bleness Majesta M Paule Charles R CR Poulain Julie J Prion Florent F Qin Baifang B Qu Chunmei C Retzel Ernest F EF Riddle Claire C Sallet Erika E Samain Sylvie S Samson Nicolas N Sanders Iryna I Saurat Olivier O Scarpelli Claude C Schiex Thomas T Segurens Béatrice B Severin Andrew J AJ Sherrier D Janine DJ Shi Ruihua R Sims Sarah S Singer Susan R SR Sinharoy Senjuti S Sterck Lieven L Viollet Agnès A Wang Bing-Bing BB Wang Keqin K Wang Mingyi M Wang Xiaohong X Warfsmann Jens J Weissenbach Jean J White Doug D DD White Jim D JD Wiley Graham B GB Wincker Patrick P Xing Yanbo Y Yang Limei L Yao Ziyun Z Ying Fu F Zhai Jixian J Zhou Liping L Zuber Antoine A Dénarié Jean J Dixon Richard A RA May Gregory D GD Schwartz David C DC Rogers Jane J Quétier Francis F Town Christopher D CD Roe Bruce A BA

Nature 20111116 7378

Legumes (Fabaceae or Leguminosae) are unique among cultivated plants for their ability to carry out endosymbiotic nitrogen fixation with rhizobial bacteria, a process that takes place in a specialized structure known as the nodule. Legumes belong to one of the two main groups of eurosids, the Fabidae, which includes most species capable of endosymbiotic nitrogen fixation. Legumes comprise several evolutionary lineages derived from a common ancestor 60 million years ago (Myr ago). Papilionoids ar ...[more]

PMID: 22089132

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The Medicago genome provides insight into the evolution of rhizobial symbioses.

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The Medicago genome provides insight into the evolution of rhizobial symbioses.

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