Medicago truncatula

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Medicago truncatula
Medicago truncatula A17 branch.JPG
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Rosids
Order: Fabales
Family: Fabaceae
Subfamily: Faboideae
Tribe: Trifolieae
Genus: Medicago
Species: M. truncatula
Binomial name
Medicago truncatula
Gaertn.
Synonyms

Medicago tribuloides Desr.
Medicago tribuloides var. breviaculeata Moris
Medicago truncatula var. breviaculeata (Moris) Urb.
Medicago truncatula var. longiaculeata Urb.
Medicago truncatula var. tribuloides (Desr.) Burnat
Medicago truncatula f. tricycla Nègre
Medicago truncatula var. tricycla (Nègre) Heyn

Medicago truncatula (Barrel Medic or Barrel Medick or Barrel Clover) is a small annual legume native to the Mediterranean region that is used in genomic research. It is a low-growing, clover-like plant 10–60 cm tall with trifoliate leaves. Each leaflet is rounded, 1–2 cm long, often with a dark spot in the center. The flowers are yellow, produced singly or in a small inflorescence of 2-5 together; the fruit is a small spiny pod.

This species is studied as a model organism for legume biology because it has a small diploid genome, is self-fertile, has a rapid generation time and prolific seed production, is amenable to genetic transformation and its genome has been sequenced.[1]

It forms symbioses with nitrogen-fixing rhizobia (Sinorhizobium meliloti and Sinorhizobium medicae) and arbuscular mycorrhizal fungi including Rhizophagus irregularis (previously known as Glomus intraradices. The model plant Arabidopsis thaliana does not form either symbiosis, making M. truncatula an important tool for studying these processes.

It is also an important forage crop species in Australia.

Sequencing of the Medicago truncatula genome[edit]

The draft sequence of the genome of M. truncatula cultivar A17 was published in the journal Nature in 2011.[1]

The sequencing was carried out by an international partnership of research laboratoriesMedicago truncatula Sequencing Consortium involving researchers from the University of Oklahoma (US), J. Craig Venter Institute (US), Genoscope (France), and Sanger Centre (UK). Partner institutions included the University of Minnesota (US), University of California-Davis (US), the National Center for Genomic Resources (NCGR) (US), John Innes Centre (UK), Institut National de Recherche Agronomique (France), Munich Information Center for Protein Sequences (MIPS) (Germany), Wageningen University (Netherlands), and Ghent University (Belgium). The Medicago truncatula Sequencing Consortium began in 2001 with a seed grant from the Samuel Roberts Noble Foundation. In 2003, the National Science Foundation and the European Union 6th Framework Programme began providing most of the funding. By 2009, 84% of the genome assembly had been completed.[2]

The assembly of the genome sequence in Medicago truncatula was based on bacterial artificial chromosomes or BACs. This is the same approach that was used to sequence the genomes of humans, the fruitfly, Drosophila melanogaster, and the model plant, Arabidopsis thaliana. In July 2013 version 4.0 of the genome was released.[3] This version combined sequences gained from shotgun sequencing with the BAC-based sequence assemblies, which has helped to fill in the gaps in the previously mapped sequences.

A parallel group known as the International Medicago Gene Annotation Group (IMGAG) is responsible for identifying and describing putative gene sequences within the genome sequence.

Symbioses with soil microorganisms[edit]

Researcher Toby Kiers of VU University Amsterdam and associates used Medicago truncatula to study symbioses between plants and fungi - and to see whether the partners in the relationship could distinguish between good and bad traders/suppliers. By using labeled carbon to track the source of nutrient flowing through the arbuscular mycorrhizal system, The researchers have proven that the plants had indeed given more carbon to the more generous fungus species. By restricting the amount of carbon the plants gave to the fungus, the researchers also demonstrated that the fungus did pass along more of their phosphorus to the more generous plants.[4]

See also[edit]

References[edit]

Further Reading[edit]

Courty, Pierre Emmanuel; Smith, Penelope; Koegel, Sally; Redecker, Dirk; Wipf, Daniel (1 June 2015). "Inorganic Nitrogen Uptake and Transport in Beneficial Plant Root-Microbe Interactions". Critical Reviews in Plant Sciences 34 (1-3): 4-16. doi:10.1080/07352689.2014.897897. 


External links[edit]