Characterization of Abrmal Anthocyanin and Proanthocyanidin Pigmentation Mutants in the Model Legume Medicago truncatula

The soilborne pathogen Ralstonia solanacearum is the causal agent of bacterial wilt and attacks more than 200 plant species, including some legumes and the model legume plant Medicago truncatula. We have demonstrated that M. truncatula accessions Jemalong A17 and F83005.5 are susceptible to R. solanacearum and, by screening 28 R. solana-cearum strains on the two M. truncatula lines, differential interactions were identified. R. solanacearum GMI1000 infected Jemalong A17 line, and disease symptoms were dependent upon functional hrp genes. An in vitro root inoculation method was employed to demonstrate that R. solanacearum colonized M. truncatula via the xylem and intercellular spaces. R. solanacearum multiplication was restricted by a factor greater than 1 × 105 in the resistant line F83005.5 compared with susceptible Jemalong A17. Genetic analysis of recombinant inbred lines from a cross between Jemalong A17 and F83005.5 revealed the presence of major quantitative trait loci for bacterial wilt resistance located on chromosome 5. The results indicate that the root pathosystem for M. truncatula will provide useful traits for molecular analyses of disease and resistance in this model plant species.

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Genome-wide identification and characterization of putative cytochrome P450 genes in the model legume Medicago truncatula

Planta ◽

10.1007/s00425-006-0473-z ◽

2007 ◽

Vol 226 (1) ◽

pp. 109-123 ◽

Cited By ~ 26

Author(s):

Lingyong Li ◽

Hao Cheng ◽

Junyi Gai ◽

Deyue Yu

Keyword(s):

Cytochrome P450 ◽

Medicago Truncatula ◽

Model Legume ◽

Genome Wide ◽

Cytochrome P450 Genes ◽

Identification And Characterization

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Molecular and physiological characterization of the monosaccharide transporters gene family in Medicago truncatula

Journal of Experimental Botany ◽

10.1093/jxb/eraa055 ◽

2020 ◽

Vol 71 (10) ◽

pp. 3110-3125

Author(s):

Fotios Komaitis ◽

Katerina Kalliampakou ◽

Maria Botou ◽

Marios Nikolaidis ◽

Chrysanthi Kalloniati ◽

...

Keyword(s):

Gene Family ◽

Medicago Truncatula ◽

Long Distance ◽

Model Legume ◽

Monosaccharide Transporter ◽

Physiological Characterization ◽

Complete Set ◽

C And N ◽

Carbon Remobilization

Abstract Monosaccharide transporters (MSTs) represent key components of the carbon transport and partitioning mechanisms in plants, mediating the cell-to-cell and long-distance distribution of a wide variety of monosaccharides. In this study, we performed a thorough structural, molecular, and physiological characterization of the monosaccharide transporter gene family in the model legume Medicago truncatula. The complete set of MST family members was identified with a novel bioinformatic approach. Prolonged darkness was used as a test condition to identify the relevant transcriptomic and metabolic responses combining MST transcript profiling and metabolomic analysis. Our results suggest that MSTs play a pivotal role in the efficient partitioning and utilization of sugars, and possibly in the mechanisms of carbon remobilization in nodules upon photosynthate-limiting conditions, as nodules are forced to acquire a new role as a source of both C and N.

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Medicago truncatulacopper transporter 1 (MtCOPT1) delivers copper for symbiotic nitrogen fixation

10.1101/104554 ◽

2017 ◽

Cited By ~ 1

Author(s):

Marta Senovilla ◽

Rosario Castro-Rodríguez ◽

Isidro Abreu ◽

Viviana Escudero ◽

Igor Kryvoruchko ◽

...

Keyword(s):

Nitrogen Fixation ◽

Medicago Truncatula ◽

Symbiotic Nitrogen Fixation ◽

Nitrogenase Activity ◽

Yeast Complementation ◽

Copper Transporter ◽

Model Legume ◽

Essential Nutrient ◽

Early Fixation

Summary• Copper is an essential nutrient for symbiotic nitrogen fixation. This element is delivered by the host plant to the nodule, where membrane copper transporter would introduce it into the cell to synthesize cupro-proteins.• COPT family members in model legumeMedicago truncatulawere identified and their expression determined. Yeast complementation assays, confocal microscopy, and phenotypical characterization of aTnt1insertional mutant line were carried out in the nodule-specificM.truncatulaCOPT family member.•Medicago truncatulagenome encodes eight COPT transporters.MtCOPT1(Medtr4g019870) is the only nodule-specificCOPTgene. It is located in the plasma membrane of the differentiation, interzone and early fixation zones. Loss of MtCOPT1 function results in a copper-mitigated reduction of biomass production when the plant obtains its nitrogen exclusively from symbiotic nitrogen fixation. Mutation ofMtCOPT1results in diminished nitrogenase activity in nodules, likely an indirect effect from the loss of a copper-dependent function, such as cytochrome oxidase activity incopt1-1bacteroids.• These data are consistent with a model in which MtCOPT1 transports copper from the apoplast into nodule cells to provide copper for essential metabolic processes associated with symbiotic nitrogen fixation.

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Characterization of dormancy behaviour in seeds of the model legume Medicago truncatula

Seed Science Research ◽

10.1017/s0960258510000061 ◽

2010 ◽

Vol 20 (2) ◽

pp. 97-107 ◽

Cited By ~ 22

Author(s):

William Bolingue ◽

Benoit Ly Vu ◽

Olivier Leprince ◽

Julia Buitink

Keyword(s):

Medicago Truncatula ◽

Initial Water Content ◽

Physical Dormancy ◽

Initial Water ◽

Model Legume ◽

Physiological Dormancy ◽

Germination Behaviour ◽

Kinetics Of

AbstractSeeds of Medicago truncatula, a genomic model species for legumes, exhibit physiological and physical dormancy. Here, the factors influencing the germination behaviour of freshly harvested and stored seeds were investigated using several genotypes. Hardseededness is promoted when mature seeds are equilibrated at relative humidities (RH) below 75%. The release of physical dormancy during imbibition was dependent on the initial water content/RH that the seeds were dried to: the drier the seeds, the longer the imbibition time needed to break physical dormancy. The kinetics of physical dormancy release was slower than that of physiological dormancy, making it possible to uncouple both phenomena. Freshly harvested embryos without seed coverings germinated at the same speed as afterripened seeds. The depth of dormancy varied between different M. truncatula genotypes, from more to less dormant: DZA315.16>A17 (Jemalong)>R108>DZA45.5. This difference was eliminated by removing the endosperm. Collectively, these observations indicate that the endosperm is likely the main factor in the reduced germination of freshly harvested seeds. White light decreased germination speed of dormant seeds whereas it had no effect on non-dormant seeds. Recently harvested seeds were most dormant at temperatures above 17°C, whereas afterripened seeds germinated over a wider range of temperature. Fluridone could efficiently break dormancy, reinforcing the role of abscisic acid (ABA) synthesis. However, dormancy was not affected by gibberellic acid (100 μM GA3) or nitrate. The particular dormancy features unravelled here for M. truncatula, combined with the available genomic resources, make it a new, useful model for genetic and molecular studies which can complement those developed for Arabidopsis.

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