Brachypodium distachyon

Brachypodium distachyon
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Monocots
Clade:	Commelinids
Order:	Poales
Family:	Poaceae
Subfamily:	Pooideae
Genus:	Brachypodium
Species:	B. distachyon
Binomial name
Brachypodium distachyon (L.) P.Beauv.

Brachypodium distachyon, commonly called purple false brome^[1] or stiff brome,^[2] is a grass species native to southern Europe, northern Africa and southwestern Asia east to India. It is related to the major cereal grain species wheat, barley, oats, maize, rice, rye, sorghum, and millet. It has many qualities that make it an excellent model organism for functional genomics research in temperate grasses, cereals, and dedicated biofuel crops such as switchgrass. These attributes include small genome (~270 Mbp) diploid accessions, a series of polyploid accessions, a small physical stature, self-fertility, a short lifecycle, simple growth requirements, and an efficient transformation system. The genome of Brachypodium distachyon (diploid inbred line Bd21) has been sequenced and published in Nature in 2010.^[3]

Although Brachypodium distachyon has little or no direct agricultural significance, it has several advantages as an experimental model organism for understanding the genetic, cellular and molecular biology of temperate grasses. The relatively small size of its genome makes it useful for genetic mapping and sequencing. In addition, only ~21% of the Brachypodium genome consists of repetitive elements, compared to 26% in rice and ~80% in wheat, further simplifying genetic mapping and sequencing.^[3] At about 272 million base pairs and with five chromosomes, it has a small genome for a grass species. Brachypodium distachyon's small size (15–20 cm) and rapid life cycle (eight to twelve weeks) are also advantageous for research purposes.^[4] For early-flowering accessions it can take as little as three weeks from germination to flower (under an appropriate inductive photoperiod). The small size of some accessions makes it convenient for cultivation in a small space. As a weed it grows easily without specialized growing conditions.

This Brachypodium is emerging as a powerful model with a growing research community. The International Brachypodium Initiative (IBI) held its first genomics meeting and workshop at the PAG XIV conference in San Diego, California, in January 2006. The goal of the IBI is to promote the development of B. distachyon as a model system and will develop and distribute genomic, genetic, and bioinformatics resources such as reference genotypes, BAC libraries, genetic markers, mapping populations, and a genome sequence database. Recently, efficient Agrobacterium-mediated transformation systems have been developed for a range of Brachypodium genotypes,^[5][6][7] enabling the development of T-DNA mutant collections.^[6][8][9] The characterization and distribution of T-DNA insertion lines has been initiated to facilitate the understanding of gene function in grasses.^[10]

By now, Brachypodium distachyon has established itself as an important tool for comparative genomics.^[11] It is now emerging as a model for crop plant disease, facilitating the model-to-crop transfer of knowledge on disease resistance.^[12] Brachypodium distachyon is also becoming a useful model system for studies of evolutionary developmental biology, in particular to contrast molecular genetic mechanisms with dicotyledon model systems, notably Arabidopsis thaliana.^[13] The finding of higher genetic diversity in eastern Iberian populations occurring in basic soils suggests that these populations can be better adapted than those occurring in western areas of the Iberian Peninsula where the soils are more acidic and accumulate toxic Al ions.^[14]

This article includes a list of general references, but it lacks sufficient corresponding inline citations. Please help to improve this article by introducing more precise citations. (April 2009) (Learn how and when to remove this message)

• Olsen, P.; Lenk, I.; Jensen, C.S.; Petersen, K.; Andersen, C.H.; Didion, T.; Nielsen, K.K. (2006). "Analysis of two heterologous flowering genes in Brachypodium distachyon demonstrates its potential as a grass model plant". Plant Science. 170 (5): 1020–5. doi:10.1016/j.plantsci.2006.01.012.
• Hasterok, R.; Marasek, A; Donnison, IS; Armstead, I; Thomas, A; King, IP; Wolny, E; Idziak, D; et al. (2006). "Alignment of the Genomes of Brachypodium distachyon and Temperate Cereals and Grasses Using Bacterial Artificial Chromosome Landing with Fluorescence in Situ Hybridization". Genetics. 173 (1): 349–62. doi:10.1534/genetics.105.049726. PMC 1461447. PMID 16489232.
• Christiansen, Pernille; Andersen, Claus Henrik; Didion, Thomas; Folling, Marianne; Nielsen, Klaus Kristian (2004). "A rapid and efficient transformation protocol for the grass Brachypodium distachyon". Plant Cell Reports. 23 (10–11): 751–8. doi:10.1007/s00299-004-0889-5. PMID 15503032. S2CID 21296533.
• Engvild, Kjeld C. (March 2005). "Mutagenesis of the Model Grass Brachypodium distachyon with Sodium Azide". Risø National Laboratory.
• Hasterok, Robert; Draper, John; Jenkins, Glyn (2004). "Laying the Cytotaxonomic Foundations of a New Model Grass, Brachypodium distachyon (L.) Beauv". Chromosome Research. 12 (4): 397–403. doi:10.1023/B:CHRO.0000034130.35983.99. PMID 15241018. S2CID 8142728.
• Routledge, Andrew P. M.; Shelley, Greg; Smith, Joel V.; Talbot, Nicholas J.; Draper, John; Mur, Luis A. J. (2004). "Magnaporthe grisea interactions with the model grass Brachypodium distachyon closely resemble those with rice (Oryza sativa)". Molecular Plant Pathology. 5 (4): 253–65. doi:10.1111/j.1364-3703.2004.00224.x. PMID 20565594.
• Mur, Luis A. J.; Xu, Renlin; Casson, Stuart A.; Stoddart, Wendy M.; Routledge, Andrew P. M.; Draper, John (2004). "Characterization of a proteinase inhibitor from Brachypodium distachyon suggests the conservation of defence signalling pathways between dicotyledonous plants and grasses". Molecular Plant Pathology. 5 (4): 267–80. doi:10.1111/j.1364-3703.2004.00225.x. PMID 20565595.
• Draper, J.; Mur, L. A.J.; Jenkins, G.; Ghosh-Biswas, G. C.; Bablak, P.; Hasterok, R.; Routledge, A. P.M. (2001). "Brachypodium distachyon. A New Model System for Functional Genomics in Grasses". Plant Physiology. 127 (4): 1539–55. doi:10.1104/pp.010196. PMC 133562. PMID 11743099.
• Catalán, Pilar; Olmstead, Richard G. (2000). "Phylogenetic reconstruction of the genus Brachypodium P. Beauv. (Poaceae) from combined sequences of chloroplastndhF gene and nuclear ITS". Plant Systematics and Evolution. 220 (1–2): 1–19. Bibcode:2000PSyEv.220....1C. doi:10.1007/BF00985367. S2CID 28594760.
• Catalán, Pilar; Shi, Ying; Armstrong, Laurel; Draper, John; Stace, Clive A. (1995). "Molecular phylogeny of the grass genus Brachypodium P. Beauv. Based on RFLP and RAPD analysis". Botanical Journal of the Linnean Society. 117 (4): 263–80. doi:10.1111/j.1095-8339.1995.tb02590.x.
• Bablak, P.; Draper, J.; Davey, M. R.; Lynch, P. T. (1995). "Plant regeneration and micropropagation of Brachypodium distachyon". Plant Cell, Tissue and Organ Culture. 42 (1): 97–107. doi:10.1007/BF00037687. S2CID 45985719.
• Hsiao, C; Chatterton, NJ; Asay, KH; Jensen, KB (1994). "Phylogenetic relationships of 10 grass species: An assessment of phylogenetic utility of the internal transcribed spacer region in nuclear ribosomal DNA in monocots". Genome. 37 (1): 112–20. doi:10.1139/g94-014. PMID 8181731.
• Shi, Ying; Draper, John; Stace, Clive (1994). "Ribosomal DNA variation and its phylogenetic implication in the genus Brachypodium (Poaceae)". Plant Systematics and Evolution. 188 (3–4): 125–38. Bibcode:1994PSyEv.188..125S. doi:10.1007/BF00937726. S2CID 11867320.

Wikimedia Commons has media related to Brachypodium distachyon.

• www.brachypodium.org - The Brachypodium distachyon Information Resource.
• www.brachybase.org - The Brachypodium distachyon Genome Browser and Annotation Database.
• "Brachypodium distachyon". Germplasm Resources Information Network. Agricultural Research Service, United States Department of Agriculture.