Publications

plants as bioreactors: a comparative study suggests that medicago truncatula is a promising production system.	plants are emerging as a promising alternative to conventional platforms for the large-scale production of recombinant proteins. this field of research, known as molecular farming, is developing rapidly and several plant-derived recombinant proteins are already in advanced clinical trials. however, the full potential of molecular farming can only be realized if we gain a fundamental understanding of biological processes regulating the production and accumulation of functional recombinant protein ...	2005	16026877
guab activity is required in rhizobium tropici during the early stages of nodulation of determinate nodules but is dispensable for the sinorhizobium meliloti-alfalfa symbiotic interaction.	the guab mutant strain rhizobium tropici ciat8999-10t is defective in symbiosis with common bean, forming nodules that lack rhizobial content. in order to investigate the timing of the guab requirement during the nodule formation on the host common bean by the strain ciat899-10.t, we constructed gene fusions in which the guab gene is expressed under the control of the symbiotic promoters noda, baca, and nifh. our data indicated that the guab is required from the early stages of nodulation becaus ...	2005	16042020
transcript enrichment of nod factor-elicited early nodulin genes in purified root hair fractions of the model legume medicago truncatula.	this article describes an efficient procedure to study nod factor-induced gene expression in root hairs of the model legume medicago truncatula. by developing an improved method of fracturing frozen root hairs, it has been possible to obtain a highly purified root hair fraction from m. truncatula seedlings yielding sufficient rna for real-time quantitative rt-pcr expression analysis. after nod factor treatment it was possible to detect up to 100-fold increases of mtenod11 and pmtenod11-gus trans ...	2005	16043451
microtubules guide root hair tip growth.	the ability to establish cell polarity is crucial to form and function of an individual cell. polarity underlies critical processes during cell development, such as cell growth, cell division, cell differentiation and cell signalling. interphase cytoplasmic microtubules in tip-growing fission yeast cells have been shown to play a particularly important role in regulating cell polarity. by placing proteins that serve as spatial cues in the cell cortex of the expanding tip, microtubules determine ...	2005	16101908
highly syntenic regions in the genomes of soybean, medicago truncatula, and arabidopsis thaliana.	recent genome sequencing enables mega-base scale comparisons between related genomes. comparisons between animals, plants, fungi, and bacteria demonstrate extensive synteny tempered by rearrangements. within the legume plant family, glimpses of synteny have also been observed. characterizing syntenic relationships in legumes is important in transferring knowledge from model legumes to crops that are important sources of protein, fixed nitrogen, and health-promoting compounds.	2005	16102170
organization and metabolism of plastids and mitochondria in arbuscular mycorrhizal roots of medicago truncatula.	colonization of root cortical cells by arbuscular mycorrhizal fungi leads to marked cytological changes of plastids and mitochondria. plastids in particular are forming tubular extensions partially connecting individual organelles in a network-like way. these cytological changes correspond to an increased need for plastid and mitochondrial products during establishment and functioning of the symbiosis. the analysis of metabolite and transcript levels in mycorrhizal and nonmycorrhizal roots from ...	2005	16126866
expression of the medicago truncatula dm12 gene suggests roles of the symbiotic nodulation receptor kinase in nodules and during early nodule development.	the medicago truncatula dmi2 gene encodes a receptorlike kinase required for establishing root endosymbioses. the dmi2 gene was shown to be expressed much more highly in roots and nodules than in leaves and stems. in roots, its expression was not altered by nitrogen starvation or treatment with lipochitooligosaccharidic nod factors. moreover, the dmi2 mrna abundance in roots of the nfp, dmil, dmi3, nsp1, nsp2, and hcl symbiotic mutants was similar to the wild type, whereas lower levels in some d ...	2005	16134899
phosphorylation and subsequent interaction with 14-3-3 proteins regulate plastid glutamine synthetase in medicago truncatula.	in this report we demonstrate that plastid glutamine synthetase of medicago truncatula (mtgs2) is regulated by phosphorylation and 14-3-3 interaction. to investigate regulatory aspects of gs2 phosphorylation, we have produced non-phosphorylated gs2 proteins by expressing the plant cdna in e. coli and performed in vitro phosphorylation assays. the recombinant isoenzyme was phosphorylated by calcium dependent kinase(s) present in leaves, roots and nodules. using an (his)6-tagged 14-3-3 protein col ...	2006	16136328
pseudomonas fluorescens and glomus mosseae trigger dmi3-dependent activation of genes related to a signal transduction pathway in roots of medicago truncatula.	plant genes induced during early root colonization of medicago truncatula gaertn. j5 by a growth-promoting strain of pseudomonas fluorescens (c7r12) have been identified by suppressive subtractive hybridization. ten m. truncatula genes, coding proteins associated with a putative signal transduction pathway, showed an early and transient activation during initial interactions between m. truncatula and p. fluorescens, up to 8 d after root inoculation. gene expression was not significantly enhanced ...	2005	16183836
rna interference identifies a calcium-dependent protein kinase involved in medicago truncatula root development.	changes in cellular or subcellular ca2+ concentrations play essential roles in plant development and in the responses of plants to their environment. however, the mechanisms through which ca2+ acts, the downstream signaling components, as well as the relationships among the various ca2+-dependent processes remain largely unknown. using an rna interference-based screen for gene function in medicago truncatula, we identified a gene that is involved in root development. silencing ca2+-dependent pro ...	2005	16199614
nod factors and a diffusible factor from arbuscular mycorrhizal fungi stimulate lateral root formation in medicago truncatula via the dmi1/dmi2 signalling pathway.	legumes form two different types of intracellular root symbioses, with fungi and bacteria, resulting in arbuscular mycorrhiza and nitrogen-fixing nodules, respectively. rhizobial signalling molecules, called nod factors, play a key role in establishing the rhizobium-legume association and genes have been identified in medicago truncatula that control a nod factor signalling pathway leading to nodulation. three of these genes, the so-called dmi1, dmi2 and dmi3 genes, are also required for formati ...	2005	16212600
crystal structures of a multifunctional triterpene/flavonoid glycosyltransferase from medicago truncatula.	glycosylation is a ubiquitous reaction controlling the bioactivity and storage of plant natural products. glycosylation of small molecules is catalyzed by a superfamily of glycosyltransferases (gts) in most plant species studied to date. we present crystal structures of the udp flavonoid/triterpene gt ugt71g1 from medicago truncatula bound to udp or udp-glucose. the structures reveal the key residues involved in the recognition of donor substrate and, by comparison with other gt structures, sugg ...	2005	16214900
the dark side of green fluorescent protein.	here, severe interference of chlorophyll with green fluorescent protein (gfp) fluorescence is described for medicago (medicago truncatula), rice (oryza sativa) and arabidopsis (arabidopsis thaliana). this interference disrupts the proportional relationship between gfp content and fluorescence that is intrinsic to its use as a quantitative reporter. the involvement of chlorophyll in the loss of gfp fluorescence with leaf age was shown in vivo, by the removal of chlorophyll through etiolation or b ...	2005	16219071
proteomic profiling unravels insights into the molecular background underlying increased aphanomyces euteiches-tolerance of medicago truncatula.	to investigate the molecular mechanisms underlying susceptibility of legumes to the root pathogen aphanomyces euteiches (oomycota), comparative proteomic studies have been carried out. in a first approach, we have analysed two medicago truncatula lines of the french core collection (f83.005-5 (r2002) and f83.005-9 (r2002)), which showed either increased or decreased susceptibility to a. euteiches as compared to the widely adopted line a17. several proteins were identified to be differentially in ...	2005	16235107
the medicago truncatula sunn gene encodes a clv1-like leucine-rich repeat receptor kinase that regulates nodule number and root length.	four medicago truncatula sunn mutants displayed shortened roots and hypernodulation under all conditions examined. the mutants, recovered in three independent genetic screens, all contained lesions in a leucine-rich repeat (lrr) receptor kinase. although the molecular defects among alleles varied, root length and the extent of nodulation were not significantly different between the mutants. sunn is expressed in shoots, flowers and roots. although previously reported grafting experiments showed t ...	2005	16240175
suppression of allene oxide cyclase in hairy roots of medicago truncatula reduces jasmonate levels and the degree of mycorrhization with glomus intraradices.	during the symbiotic interaction between medicago truncatula and the arbuscular mycorrhizal (am) fungus glomus intraradices, an endogenous increase in jasmonic acid (ja) occurs. two full-length cdnas coding for the ja-biosynthetic enzyme allene oxide cyclase (aoc) from m. truncatula, designated as mtaoc1 and mtaoc2, were cloned and characterized. the aoc protein was localized in plastids and found to occur constitutively in all vascular tissues of m. truncatula. in leaves and roots, mtaocs are e ...	2005	16244141
methylotrophic metabolism is advantageous for methylobacterium extorquens during colonization of medicago truncatula under competitive conditions.	facultative methylotrophic bacteria of the genus methylobacterium are commonly found in association with plants. inoculation experiments were performed to study the importance of methylotrophic metabolism for colonization of the model legume medicago truncatula. competition experiments with methylobacterium extorquens wild-type strain am1 and methylotrophy mutants revealed that the ability to use methanol as a carbon and energy source provides a selective advantage during colonization of m. trun ...	2005	16269765
significant microsynteny with new evolutionary highlights is detected between arabidopsis and legume model plants despite the lack of macrosynteny.	the increased amount of data produced by large genome sequencing projects allows scientists to carry out important syntenic studies to a great extent. detailed genetic maps and entirely or partially sequenced genomes are compared, and macro- and microsyntenic relations can be determined for different species. in our study, the syntenic relationships between key legume plants and two model plants, arabidopsis thaliana and populus trichocarpa were investigated. the comparison of the map position o ...	2005	16273388
arbuscular mycorrhizal fungi elicit a novel intracellular apparatus in medicago truncatula root epidermal cells before infection.	the penetration of arbuscular mycorrhizal (am) fungi through the outermost root tissues of the host plant is a critical step in root colonization, ultimately leading to the establishment of this ecologically important endosymbiotic association. to evaluate the role played by the host plant during am infection, we have studied in vivo cellular dynamics within medicago truncatula root epidermal cells using green fluorescent protein labeling of both the plant cytoskeleton and the endoplasmic reticu ...	2005	16284314
sini- and expr-dependent quorum sensing in sinorhizobium meliloti.	quorum sensing (qs) in sinorhizobium meliloti, the n-fixing bacterial symbiont of medicago host plants, involves at least half a dozen different n-acyl homoserine lactone (ahl) signals and perhaps an equal number of ahl receptors. the accumulation of 55 proteins was found to be dependent on sini, the ahl synthase, and/or on expr, one of the ahl receptors. gas chromatography-mass spectrometry and electrospray ionization tandem mass spectrometry identified 3-oxo-c(14)-homoserine lactone (3-oxo-c(1 ...	2005	16291666
competitive abilities of rhizobium meliloti strains considered to have potential as inoculants.	twenty four strains of rhizobium meliloti considered to have potential for inoculant production were grouped in pairs and tested for their ability to compete for nodulation on medicago sativa, medicago truncatula, and medicago littoralis. at the outset, each pair of strains, which consisted of a wild type and a selected streptomycin-resistant mutant of another strain, was tested in an autoclaved soil. six strain pairs, each consisting of a good and a poor competitor, reacted consistently when te ...	1982	16346072
nod factors alter the microtubule cytoskeleton in medicago truncatula root hairs to allow root hair reorientation.	the microtubule (mt) cytoskeleton is an important part of the tip-growth machinery in legume root hairs. here we report the effect of nod factor (nf) on mts in root hairs of medicago truncatula. in tip-growing hairs, the ones that typically curl around rhizobia, nf caused a subtle shortening of the endoplasmic mt array, which recovered within 10 min, whereas cortical mts were not visibly affected. in growth-arresting root hairs, endoplasmic mts disappeared shortly after nf application, but refor ...	2005	16353554
changes in chloroplast dna during development in tobacco, medicago truncatula, pea, and maize.	we examined the dna from chloroplasts obtained from young and fully expanded leaves of tobacco (nicotiana tabacum l.), medicago truncatula, pea (pisum sativum l.), and maize (zea mays l.). the changes in plastid dna content and structure were monitored by four independent methods: 4',6-diamidino-2-phenylindole (dapi) staining with intact chloroplasts, in situ dapi staining of cytological sections, ethidium bromide staining at the single-molecule level after exhaustive deproteinization of lysed c ...	2006	16362324
transcript analysis of early nodulation events in medicago truncatula.	within the first 72 h of the interaction between rhizobia and their host plants, nodule primordium induction and infection occur. we predicted that transcription profiling of early stages of the symbiosis between medicago truncatula roots and sinorhizobium meliloti would identify regulated plant genes that likely condition key events in nodule initiation. therefore, using a microarray with about 6,000 cdnas, we compared transcripts from inoculated and uninoculated roots corresponding to defined ...	2006	16377745
the dmi1 and dmi2 early symbiotic genes of medicago truncatula are required for a high-affinity nodulation factor-binding site associated to a particulate fraction of roots.	the establishment of the legume-rhizobia symbiosis between medicago spp. and sinorhizobium meliloti is dependent on the production of sulfated lipo-chitooligosaccharidic nodulation (nod) factors by the bacterial partner. in this article, using a biochemical approach to characterize putative nod factor receptors in the plant host, we describe a high-affinity binding site (kd = 0.45 nm) for the major nod factor produced by s. meliloti. this site is termed nod factor-binding site 3 (nfbs3). nfbs3 i ...	2006	16377749
architecture of infection thread networks in developing root nodules induced by the symbiotic bacterium sinorhizobium meliloti on medicago truncatula.	during the course of the development of nitrogen-fixing root nodules induced by sinorhizobium meliloti on the model plant medicago truncatula, tubules called infection threads are cooperatively constructed to deliver the bacterial symbiont from the root surface to cells in the interior of the root and developing nodule. three-dimensional reconstructions of infection threads inside m. truncatula nodules showed that the threads formed relatively simple, tree-like networks. some characteristics of ...	2006	16384905
nitrogen fixation mutants of medicago truncatula fail to support plant and bacterial symbiotic gene expression.	the rhizobium-legume symbiosis culminates in the exchange of nutrients in the root nodule. bacteria within the nodule reduce molecular nitrogen for plant use and plants provide bacteria with carbon-containing compounds. following the initial signaling events that lead to plant infection, little is known about the plant requirements for establishment and maintenance of the symbiosis. we screened 44,000 m2 plants from fast neutron-irradiated medicago truncatula seeds and isolated eight independent ...	2006	16407449
tracing nonlegume orthologs of legume genes required for nodulation and arbuscular mycorrhizal symbioses.	most land plants can form a root symbiosis with arbuscular mycorrhizal (am) fungi for assimilation of inorganic phosphate from the soil. in contrast, the nitrogen-fixing root nodule symbiosis is almost completely restricted to the legumes. the finding that the two symbioses share common signaling components in legumes suggests that the evolutionarily younger nitrogen-fixing symbiosis has recruited functions from the more ancient am symbiosis. the recent advances in cloning of the genes required ...	2006	16452143
mtenod11 gene activation during rhizobial infection and mycorrhizal arbuscule development requires a common at-rich-containing regulatory sequence.	the mtenod11 gene from the model legume medicago truncatula is transcriptionally activated both in response to sinorhizobium meliloti nod factors and throughout infection of root tissues by the nitrogen-fixing microsymbiont. to identify the regulatory sequences involved in symbiosis-related mtenod11 expression, a series of promoter deletions driving the beta-glucuronidase reporter gene were analyzed in transgenic m. truncatula roots. these studies have revealed that distinct regulatory regions a ...	2005	16478046
master: a novel family of pif/harbinger-like transposable elements identified in carrot (daucus carota l.).	members of a novel master family of class ii transposons were identified in the carrot genome. two elements, 2.5 kb long dcmaster1 and 4.4 kb long dcmaster-a, are characterized by 22 bp imperfect terminal inverted repeats and by 3 bp target site duplications. genbank search revealed that related elements are also present in medicago truncatula, including a 5.1 kb element mtmaster-a. both dcmaster-a and mtmaster-a contain open reading frames encoding for putative transposases with the complete dd ...	2006	16482474
defective long-distance auxin transport regulation in the medicago truncatula super numeric nodules mutant.	long-distance auxin transport was examined in medicago truncatula and in its supernodulating mutant sunn (super numeric nodules) to investigate the regulation of auxin transport during autoregulation of nodulation (aon). a method was developed to monitor the transport of auxin from the shoot to the root in whole seedlings. subsequently, the transport was monitored after inoculation of roots with the nodulating symbiont sinorhizobium meliloti. the sunn mutant showed an increased amount of auxin t ...	2006	16489131
metabolic engineering of proanthocyanidins through co-expression of anthocyanidin reductase and the pap1 myb transcription factor.	proanthocyanidins (pas) and their monomeric building blocks, the (epi)-flavan-3-ols, are plant antioxidants that confer multiple human health benefits. the presence of pas in forage crops is an important agronomic trait, preventing pasture bloat in ruminant animals. however, many consumed plant materials lack pas, and there has been little success to date in introducing monomeric or polymeric flavan-3-ols de novo into plant tissues for disease prevention by dietary means or development of 'bloat ...	2006	16507081
medicago truncatula mutants demonstrate the role of plant calcium oxalate crystals as an effective defense against chewing insects.	calcium oxalate is the most abundant insoluble mineral found in plants and its crystals have been reported in more than 200 plant families. in the barrel medic medicago truncatula gaertn., these crystals accumulate predominantly in a sheath surrounding secondary veins of leaves. mutants of m. truncatula with decreased levels of calcium oxalate crystals were used to assess the defensive role of this mineral against insects. caterpillar larvae of the beet armyworm spodoptera exigua hübner show a c ...	2006	16514014
caterpillar herbivory and salivary enzymes decrease transcript levels of medicago truncatula genes encoding early enzymes in terpenoid biosynthesis.	in response to caterpillar herbivory, alfalfa and related plant species defend themselves through the induction of saponin and volatile terpenoid biosynthesis. both these types of defensive compounds are derived from the metabolic intermediate, isopentenyl diphosphate (ipp). in plants, two distinct biosynthetic pathways can generate ipp; the cytosolic mevalonate pathway and the plastid-associated 2c-methyl erythritol 4-phosphate (mep) pathway. in medicago truncatula, transcript levels of key reg ...	2006	16525889
recruitment of novel calcium-binding proteins for root nodule symbiosis in medicago truncatula.	legume rhizobia symbiotic nitrogen (n2) fixation plays a critical role in sustainable nitrogen management in agriculture and in the earth's nitrogen cycle. signaling between rhizobia and legumes initiates development of a unique plant organ, the root nodule, where bacteria undergo endocytosis and become surrounded by a plant membrane to form a symbiosome. between this membrane and the encased bacteria exists a matrix-filled space (the symbiosome space) that is thought to contain a mixture of pla ...	2006	16543412
activation of an alfalfa cyclin-dependent kinase inhibitor by calmodulin-like domain protein kinase.	kip-related proteins (krps) play a central role in the regulation of the cell cycle and differentiation through modulation of cyclin-dependent kinase (cdk) functions. we have identified a cdk inhibitor gene from medicago truncatula (mt) by a yeast two-hybrid screen. the krpmt gene was expressed in all plant organs and cultured cells, and its transcripts accumulated after abscisic acid and nacl treatment. the krpmt protein exhibits seven conserved sequence domains and a pest motif that is also de ...	2006	16553899
insights into symbiotic nitrogen fixation in medicago truncatula.	in silico analysis of the medicago truncatula gene index release 8.0 at the institute for genomic research identified approximately 530 tentative consensus sequences (tc) clustered from 2,700 expressed sequence tags (est) derived solely from sinorhizobium meliloti-inoculated root and nodule tissues. a great majority (76%) of these tc were derived exclusively from nitrogen-fixing and senescent nodules. a cdna filter array was constructed using approximately 58% of the in silico-identified tc as w ...	2006	16570662
transgenic medicago truncatula plants obtained from agrobacterium tumefaciens -transformed roots and agrobacterium rhizogenes-transformed hairy roots.	medicago truncatula, barrel medic, is a forage crop that has been developed into a model legume. the development of new transformation methods is important for functional genomic studies in this species. based on agrobacterium tumefaciens-mediated transformation of root explants, we developed an effective system for producing m. truncatula (genotype r108) transgenic plants. among the four a. tumefaciens strains (agl1, c58c1, eha105 and lba4404) tested, eha105 and agl1 were most effective in rege ...	2006	16575594
the conserved arbuscular mycorrhiza-specific transcription of the secretory lectin mtlec5 is mediated by a short upstream sequence containing specific protein binding sites.	in medicago truncatula a family of mycorrhiza-specific expressed lectins has been identified recently, but the function and regulation of these lectins during the arbuscular mycorrhiza symbiosis are still unknown. in order to characterize a first member of this protein family, mtlec5 was analyzed concerning its localization and regulation. confocal laser scanning microscopy showed that mtlec5 is a secretory protein indicating a role as a vegetative storage protein, which is specifically expresse ...	2006	16596411
plant fatty acid (ethanol) amide hydrolases.	fatty acid amide hydrolase (faah) plays a central role in modulating endogenous n-acylethanolamine (nae) levels in vertebrates, and, in part, constitutes an "endocannabinoid" signaling pathway that regulates diverse physiological and behavioral processes in animals. recently, an arabidopsis faah homologue was identified which catalyzed the hydrolysis of naes in vitro suggesting a faah-mediated pathway exists in plants for the metabolism of endogenous naes. here, we provide evidence to support th ...	2006	16624618
aging in legume symbiosis. a molecular view on nodule senescence in medicago truncatula.	rhizobia reside as symbiosomes in the infected cells of legume nodules to fix atmospheric nitrogen. the symbiotic relation is strictly controlled, lasts for some time, but eventually leads to nodule senescence. we present a comprehensive transcriptomics study to understand the onset of nodule senescence in the legume medicago truncatula. distinct developmental stages with characteristic gene expression were delineated during which the two symbiotic partners were degraded consecutively, marking t ...	2006	16648219
a rice calcium- and calmodulin-dependent protein kinase restores nodulation to a legume mutant.	the medicago truncatula dmi3 gene encodes a calcium- and calmodulin-dependent protein kinase (ccamk) that is necessary for the establishment of both rhizobial and mycorrhizal symbioses. the two symbiotic signaling pathways diverge downstream of dmi3; therefore, it has been proposed that legumes have evolved a particular form of ccamk, acting like a switch able both to discriminate between rhizobial and mycorrhizal calcium signatures and to trigger the appropriate downstream signaling pathway. to ...	2006	16673936
lysm domains of medicago truncatula nfp protein involved in nod factor perception. glycosylation state, molecular modeling and docking of chitooligosaccharides and nod factors.	the establishment of the symbiosis between legume plants and rhizobial bacteria depends on the production of rhizobial lipo-chitooligosaccharidic signals (the nod factors) that are specifically recognized by roots of the host plant. in medicago truncatula, specific recognition of sinorhizobium meliloti and its nod factors requires the nfp (nod factor perception) gene, which encodes a putative serine/threonine receptor-like kinase (rlk). the extracellular region of this protein contains three tan ...	2006	16723404
silencing the flavonoid pathway in medicago truncatula inhibits root nodule formation and prevents auxin transport regulation by rhizobia.	legumes form symbioses with rhizobia, which initiate the development of a new plant organ, the nodule. flavonoids have long been hypothesized to regulate nodule development through their action as auxin transport inhibitors, but genetic proof has been missing. to test this hypothesis, we used rna interference to silence chalcone synthase (chs), the enzyme that catalyzes the first committed step of the flavonoid pathway, in medicago truncatula. agrobacterium rhizogenes transformation was used to ...	2006	16751348
comprehensive structural analysis of the genome of red clover (trifolium pratense l.).	with the aim of establishing the basic knowledge and resources needed for applied genetics, we investigated the genome structure of red clover trifolium pratense l. by a combination of cytological, genomic and genetic approaches. the deduced genome size was approximately 440 mb, as estimated by measuring the nuclear dna content by flow cytometry. seven chromosomes could be distinguished by microscopic observation of dapi stained prometaphase chromosomes and fluorescence in situ hybridization usi ...	2005	16769692
effects of endogenous salicylic acid on nodulation in the model legumes lotus japonicus and medicago truncatula.	the exogenous addition of salicylic acid (sa) was previously shown to inhibit indeterminate but not determinate-type nodulation. we sought to extend these results by modulating endogenous levels of sa through the transgenic expression of salicylate hydroxylase (nahg) in both stably transformed lotus japonicus and composite medicago truncatula plants. nahg expression in l. japonicus resulted in a marked reduction of sa levels. this reduction correlated with an increase in the number of infections ...	2006	16798946
indole-3-acetic acid protein conjugates: novel players in auxin homeostasis.	indole-3-acetic acid (iaa) is found in plants in both free and conjugated forms. within the group of conjugated iaa there is a unique class of proteins and peptides where iaa is attached directly to the polypeptide structure as a prosthetic group. the first gene, iap1, encoding for a protein with iaa as a prosthetic group, was cloned from bean (phaseolus vulgaris). it was shown that the expression of iap1 as a major iaa modified protein in bean seed (pviap1) was correlated to a developmental per ...	2006	16807826
nodulation independent of rhizobia induced by a calcium-activated kinase lacking autoinhibition.	legumes, such as medicago truncatula, form mutualistic symbiotic relationships with nitrogen-fixing rhizobial bacteria. this occurs within specialized root organs--nodules--that provide the conditions required for nitrogen fixation. a rhizobium-derived signalling molecule, nod factor, is required to establish the symbiosis. perception of nod factor in the plant leads to the induction of ca2+ oscillations, and the transduction of this ca2+ signal requires dmi3 (refs 2, 3), which encodes the prote ...	2006	16810256
the medicago truncatula lysin [corrected] motif-receptor-like kinase gene family includes nfp and new nodule-expressed genes.	rhizobial nod factors are key symbiotic signals responsible for starting the nodulation process in host legume plants. of the six medicago truncatula genes controlling a nod factor signaling pathway, nod factor perception (nfp) was reported as a candidate nod factor receptor gene. here, we provide further evidence for this by showing that nfp is a lysin [corrected] motif (lysm)-receptor-like kinase (rlk). nfp was shown both to be expressed in association with infection thread development and to ...	2006	16844829
the ethylene-insensitive sickle mutant of medicago truncatula shows altered auxin transport regulation during nodulation.	we studied the ethylene-insensitive, hypernodulating mutant, sickle (skl), to investigate the interaction of ethylene with auxin transport during root nodulation in medicago truncatula. grafting experiments demonstrated that hypernodulation in skl is root controlled. long distance transport of auxin from shoot to root was reduced by rhizobia after 24 h in wild type but not in skl. similarly, the ethylene precursor 1-amino cyclopropane-1-carboxylic acid inhibited auxin transport in wild type but ...	2006	16844840
ftsz characterization and immunolocalization in the two phases of plastid reorganization in arbuscular mycorrhizal roots of medicago truncatula.	we have analyzed plastid proliferation in root cortical cells of medicago truncatula colonized by arbuscular mycorrhizal (am) fungi by concomitantly labeling fungal structures, root plastids, a protein involved in plastid division (ftsz1) and a protein involved in the biosynthesis of am-specific apocarotenoids. antibodies directed against ftsz1 have been generated after heterologous expression of the respective gene from m. truncatula and characterization of the gene product. analysis of enzymat ...	2006	16854943
gc-ms based metabolite profiling implies three interdependent ways of ammonium assimilation in medicago truncatula root nodules.	in symbiotic interaction with legume plants, bacteria termed rhizobia can fix massive amounts of atmospheric nitrogen which is primarily provided in the form of ammonium to the host plants. therefore, legume root nodules that house the symbiotic bacteria are ideally suited to study the process of primary ammonium assimilation. here, we present a gc-ms based metabolite profiling analysis of medicago truncatula root nodules (induced by the bacterium sinorhizobium meliloti) before and after inhibit ...	2006	16870293
isolation and characterization of root-specific phosphate transporter promoters from medicago trunatula.	promoters of phosphate transporter genes mtpt1 and mtpt2 of medicago truncatula were isolated by utilizing the gene-space sequence information and by screening of a genomic library, respectively. two reporter genes, beta-glucuronidase (gus) and green fluorescent protein (gfp) were placed under the control of the mtpt1 and mtpt2 promoters. these chimeric transgenes were introduced into arabidopsis thaliana and transgenic roots of m. truncatula, and expression patterns of the reporter genes were a ...	2006	16917979
legumedb1 bioinformatics resource: comparative genomic analysis and novel cross-genera marker identification in lupin and pasture legume species.	the identification of markers in legume pasture crops, which can be associated with traits such as protein and lipid production, disease resistance, and reduced pod shattering, is generally accepted as an important strategy for improving the agronomic performance of these crops. it has been demonstrated that many quantitative trait loci (qtls) identified in one species can be found in other plant species. detailed legume comparative genomic analyses can characterize the genome organization betwe ...	2006	16936848
genetic diversity of crotalaria germplasm assessed through phylogenetic analysis of est-ssr markers.	the genetic diversity of the genus crotalaria is unknown even though many species in this genus are economically valuable. we report the first study in which polymorphic expressed sequence tag-simple sequence repeat (est-ssr) markers derived from medicago and soybean were used to assess the genetic diversity of the crotalaria germplasm collection. this collection consisted of 26 accessions representing 4 morphologically characterized species. phylogenetic analysis partitioned accessions into 4 m ...	2006	16936850
nitric oxide is formed in medicago truncatula-sinorhizobium meliloti functional nodules.	nitric oxide (no) has recently gained interest as a major signaling molecule during plant development and response to environmental cues. its role is particularly crucial for plant-pathogen interactions, during which it participates in the control of plant defense response and resistance. indication for the presence of no during symbiotic interactions has also been reported. here, we defined when and where no is produced during medicago truncatula-sinorhizobium meliloti symbiosis. using the no-s ...	2006	16941901
medicago truncatula syntaxin syp132 defines the symbiosome membrane and infection droplet membrane in root nodules.	symbiotic association of legume plants with rhizobia bacteria culminates in organogenesis of nitrogen-fixing root nodules. in indeterminate nodules, plant cells accommodate rhizobial infection by enclosing each bacterium in a membrane-bound, organelle-like compartment called the symbiosome. numerous symbiosomes occupy each nodule cell; therefore an enormous amount of membrane material must be delivered to the symbiosome membrane for its development and maintenance. protein delivery to the symbio ...	2007	16944200
phosphoproteins analysis in plants: a proteomic approach.	the study of phosphoproteome on a global scale represents one of the challenges in the post-genomic era. here, we propose an integrated procedure starting from the crude protein extract, that consists of sequential purification steps, and ending up in the identification of phosphorylation sites. this involves (i) an enrichment in phosphoproteins with a commercially available chromatography matrix, (ii) a 2-d gel analysis of the enriched fraction followed by the selective staining with the phosph ...	2006	16962150
extracellular atp in plants. visualization, localization, and analysis of physiological significance in growth and signaling.	extracellular atp (eatp) in animals is well documented and known to play an important role in cellular signaling (e.g. at the nerve synapse). the existence of eatp has been postulated in plants; however, there is no definitive experimental evidence for its presence or an explanation as to how such a polar molecule could exit the plant cell and what physiological role it may play in plant growth and development. the presence of eatp in plants (medicago truncatula) was detected by constructing a n ...	2006	16963521
isolation of mtpim proves tnt1 a useful reverse genetics tool in medicago truncatula and uncovers new aspects of ap1-like functions in legumes.	comparative studies help shed light on how the huge diversity in plant forms found in nature has been produced. we use legume species to study developmental differences in inflorescence architecture and flower ontogeny with classical models such as arabidopsis thaliana or antirrhinum majus. whereas genetic control of these processes has been analyzed mostly in pea (pisum sativum), medicago truncatula is emerging as a promising alternative system for these studies due to the availability of a ran ...	2006	16963524
ralstonia solanacearum requires f-box-like domain-containing type iii effectors to promote disease on several host plants.	the phytopathogenic bacterium ralstonia solanacearum encodes a family of seven type iii secretion system (t3ss) effectors that contain both a leucine-rich repeat and an f-box domain. this structure is reminiscent of a class of typical eukaryotic proteins called f-box proteins. the latter, together with skp1 and cullin1 subunits, constitute the scf-type e3 ubiquitin ligase complex and control specific protein ubiquitinylation. in the eukaryotic cell, depending on the nature of the polyubiquitin c ...	2006	16983093
medicago truncatula transformation using leaf explants.	legumes have long been recalcitrant to efficient agrobacterium tumefaciens-mediated transformation. the choice and use of model legume plants (medicago truncatula and lotus japonicus) for molecular studies has triggered extensive studies devoted to the development of efficient agrobacterium-mediated transformation protocols for these two plants. in m. truncatula, transformation protocols rely on the use of highly regenerable lines obtained by recurrent in vitro culture selection. these protocols ...	2006	16988338
medicago truncatula transformation using cotyledon explants.	medicago truncatula has been developed into a model species for legumes. large numbers of ests have been sequenced, and sequencing of the complete gene-rich space of the genotype jemalong a17 is in progress. by using cotyledons as explants for agrobacterium infection and direct shoot formation, this protocol allows for rapid production of transgenic plants from a17 and other genotypes. transgenic plants can be regenerated and established in the greenhouse in only 3-4 mo after agrobacterium-media ...	2006	16988339
medicago truncatula transformation using root explants.	medicago truncatula is a forage crop that has been developed into a model legume. as a model plant, m. truncatula is particularly useful for the study of root endosymbiotic associations, including nodulation and mycorrhizal colonization. the development of different transformation methods is an important aspect for functional genomic studies in the species. this protocol describes an efficient system for generating transgenic plants from m. truncatula roots based on agrobacterium tumefaciens-med ...	2006	16988340
functional analysis of members of the isoflavone and isoflavanone o-methyltransferase enzyme families from the model legume medicago truncatula.	previous studies have identified two distinct o-methyltransferases (omts) implicated in isoflavonoid biosynthesis in medicago species, a 7-omt methylating the a-ring 7-hydroxyl of the isoflavone daidzein and a 4'-omt methylating the b-ring 4'-hydroxyl of 2,7,4'-trihydroxyisoflavanone. genes related to these omts from the model legume medicago truncatula cluster as separate branches of the type i plant small molecule omt family. to better understand the possible functions of these related omts in ...	2006	17001495
salt-tolerant rhizobia isolated from a tunisian oasis that are highly effective for symbiotic n2-fixation with phaseolus vulgaris constitute a novel biovar (bv. mediterranense) of sinorhizobium meliloti.	nodulation of common bean was explored in six oases in the south of tunisia. nineteen isolates were characterized by pcr-rflp of 16s rdna. three species of rhizobia were identified, rhizobium etli, rhizobium gallicum and sinorhizobium meliloti. the diversity of the symbiotic genes was then assessed by pcr-rflp of nodc and nifh genes. the majority of the symbiotic genotypes were conserved between oases and other soils of the north of the country. sinorhizobia isolated from bean were then compared ...	2007	17019605
the medicago truncatula cre1 cytokinin receptor regulates lateral root development and early symbiotic interaction with sinorhizobium meliloti.	legumes develop different types of lateral organs from their primary root, lateral roots and nodules, the latter depending on a symbiotic interaction with sinorhizobium meliloti. phytohormones have been shown to function in the control of these organogeneses. however, related signaling pathways have not been identified in legumes. we cloned and characterized the expression of medicago truncatula genes encoding members of cytokinin signaling pathways. rna interference of the cytokinin receptor ho ...	2006	17028204
geminivirus infection up-regulates the expression of two arabidopsis protein kinases related to yeast snf1- and mammalian ampk-activating kinases.	geminivirus rep-interacting kinase 1 (grik1) and grik2 constitute a small protein kinase family in arabidopsis (arabidopsis thaliana). an earlier study showed that a truncated version of grik1 binds to the geminivirus replication protein al1. we show here both full-length grik1 and grik2 interact with al1 in yeast two-hybrid studies. using specific antibodies, we showed that both arabidopsis kinases are elevated in infected leaves. immunoblot analysis of healthy plants revealed that grik1 and gr ...	2006	17041027
extending mapman: application to legume genome arrays.	based on a gene classification into hierarchical categories ('bins'), mapman was originally developed to display arabidopsis thaliana gene expression in a functional context. we have created a bioinformatics system to extend mapman to any organism by using a new bin structure based on the kegg database. gene sequences are assigned to this ontology by homology relationships in four reference databases: kegg, cog, swiss-prot and gene ontology. we applied this system to tailor mapman to the genechi ...	2006	17046975
lotus japonicus nodulation requires two gras domain regulators, one of which is functionally conserved in a non-legume.	a new nodulation-defective mutant of lotus japonicus does not initiate nodule cortical cell division in response to mesorhizobium loti, but induces root hair deformation, nod factor-induced calcium spiking, and mycorrhization. this phenotype, together with mapping data, suggested that the mutation could be in the ortholog of the medicago truncatula nsp1 gene (mtnsp1). the sequence of the orthologous gene (ljnsp1) in the l. japonicus mutant (ljnsp1-1) revealed a mutation causing a premature stop ...	2006	17071642
cyp74c3 and cyp74a1, plant cytochrome p450 enzymes whose activity is regulated by detergent micelle association, and proposed new rules for the classification of cyp74 enzymes.	cyp74c3 (cytochrome p450 subfamily 74c3), an hpl (hydroperoxide lyase) from medicago truncatula (barrel medic), and cyp74a1, an aos (allene oxide synthase) from arabidopsis thaliana, are key membrane-associated p450 enzymes in plant oxylipin metabolism. both recombinant detergent-free enzymes are monomeric proteins with dual specificity and very low enzyme activity that can be massively activated with detergent. this effect is a result of the formation of a complex between the protein monomer an ...	2006	17073790
identification of ethylene-mediated protein changes during nodulation in medicago truncatula using proteome analysis.	ethylene has been hypothesised to be a regulator of root nodule development in legumes, but its molecular mechanisms of action remain unclear. the skl mutant is an ethylene-insensitive legume mutant showing a hypernodulation phenotype when inoculated with its symbiont sinorhizobium meliloti. we used the skl mutant to study the ethylene-mediated protein changes during nodule development in medicago truncatula. we compared the root proteome of the skl mutant to its wild-type in response to the eth ...	2006	17081060
development of bioinformatic tools to support est-sequencing, in silico- and microarray-based transcriptome profiling in mycorrhizal symbioses.	the great majority of terrestrial plants enters a beneficial arbuscular mycorrhiza (am) or ectomycorrhiza (ecm) symbiosis with soil fungi. in the spp 1084 "molmyk: molecular basics of mycorrhizal symbioses", high-throughput est-sequencing was performed to obtain snapshots of the plant and fungal transcriptome in mycorrhizal roots and in extraradical hyphae. to focus activities, the interactions between medicago truncatula and glomus intraradices as well as populus tremula and amanita muscaria we ...	2007	17081576
gene expression analysis of arbuscule development and functioning.	the arbuscular mycorrhiza (am) is characterized by specific morphological structures of the fungus and the plant and by physiological adaptations which are mostly beneficial for both partners of the symbiosis. this review describes approaches to study the molecular basis of the interaction. rna accumulation patterns have been monitored in pisum sativum to analyse the plant response to arbuscule development. in a direct approach, the mtha1 gene from medicago truncatula was cloned which is express ...	2007	17081578
a novel family of lectins evolutionarily related to class v chitinases: an example of neofunctionalization in legumes.	a lectin has been identified in black locust (robinia pseudoacacia) bark that shares approximately 50% sequence identity with plant class v chitinases but is essentially devoid of chitinase activity. specificity studies indicated that the black locust chitinase-related agglutinin (robpscra) preferentially binds to high-mannose n-glycans comprising the proximal pentasaccharide core structure. closely related orthologs of robpscra could be identified in the legumes glycine max, medicago truncatula ...	2007	17098856
mthap2-1 is a key transcriptional regulator of symbiotic nodule development regulated by microrna169 in medicago truncatula.	in the model legume medicago truncatula, we identified a new transcription factor of the ccaat-binding family, mthap2-1, for which rna interference (rnai) and in situ hybridization experiments indicate a key role during nodule development, possibly by controlling nodule meristem function. we could also show that mthap2-1 is regulated by microrna169, whose overexpression leads to the same nodule developmental block as mthap2-1 rnai constructs. the complementary expression pattern of mir169 and mt ...	2006	17114582
a cdpk isoform participates in the regulation of nodule number in medicago truncatula.	medicago spp. are able to develop root nodules via symbiotic interaction with sinorhizobium meliloti. calcium-dependent protein kinases (cdpks) are involved in various signalling pathways in plants, and we found that expression of mtcpk3, a cdpk isoform present in roots of the model legume medicago truncatula, is regulated during the nodulation process. early inductions were detected 15 min and 3-4 days post-inoculation (dpi). the very early induction of cpk3 messengers was also present in inocu ...	2006	17132148
towards the elucidation of am-specific transcription in medicago truncatula.	roots of most plants form a mutualistic interaction with arbuscular mycorrhiza (am) fungi. during the symbiosis, drastic morphological and physiological changes occur in the host plant root system. these changes are likely to be controlled by a specific genetic program of the plant. the legume medicago truncatula is a model system widely used to elucidate this program. a number of loci required for am-development have been identified by the analysis of m. truncatula mutants; however, the genes i ...	2007	17141285
a diffusible signal from arbuscular mycorrhizal fungi elicits a transient cytosolic calcium elevation in host plant cells.	the implication of calcium as intracellular messenger in the arbuscular mycorrhizal (am) symbiosis has not yet been directly demonstrated, although often envisaged. we used soybean (glycine max) cell cultures stably expressing the bioluminescent ca(2+) indicator aequorin to detect intracellular ca(2+) changes in response to the culture medium of spores of gigaspora margarita germinating in the absence of the plant partner. rapid and transient elevations in cytosolic free ca(2+) were recorded, in ...	2007	17142489
structural basis for dual functionality of isoflavonoid o-methyltransferases in the evolution of plant defense responses.	in leguminous plants such as pea (pisum sativum), alfalfa (medicago sativa), barrel medic (medicago truncatula), and chickpea (cicer arietinum), 4'-o-methylation of isoflavonoid natural products occurs early in the biosynthesis of defense chemicals known as phytoalexins. however, among these four species, only pea catalyzes 3-o-methylation that converts the pterocarpanoid isoflavonoid 6a-hydroxymaackiain to pisatin. in pea, pisatin is important for chemical resistance to the pathogenic fungus ne ...	2006	17172354
the symbiotic ion channel homolog dmi1 is localized in the nuclear membrane of medicago truncatula roots.	legumes utilize a common signaling pathway to form symbiotic associations both with rhizobial bacteria and arbuscular mycorrhizal fungi. the perception of microbial signals is believed to take place at the plasma membrane, activating a cascade that converges on the nucleus where transcriptional reprogramming facilitates the symbioses. forward genetic strategies have identified genes in this signaling pathway including medicago truncatula dmi1 (doesn't make infections 1) that encodes a putative i ...	2007	17173544
a transient decrease in reactive oxygen species in roots leads to root hair deformation in the legume-rhizobia symbiosis.	* a possible role for reactive oxygen species (ros) in root hair deformation in response to nod factor (nf) was investigated using medicago truncatula nodulation mutants, and an inhibitor and precursors of ros. * in wild-type roots, ros efflux transiently decreased approximately 1 h after nf treatment. transcript accumulation of two nadph oxidase homologs, respiratory burst oxidase homolog 2 (mtrboh2) and mtrboh3, also transiently decreased at 1 h. however, in the nonnodulating mutant nod factor ...	2007	17176392
validation of in silico-predicted genic snps in white clover (trifolium repens l.), an outbreeding allopolyploid species.	white clover (trifolium repens l.) is an obligate outbreeding allotetraploid forage legume. gene-associated snps provide the optimum genetic system for improvement of such crop species. an est resource obtained from multiple cdna libraries constructed from numerous genotypes of a single cultivar has been used for in silico snp discovery and validation. a total of 58 from 236 selected sequence clusters (24.5%) were fully validated as containing polymorphic snps by genotypic analysis across the pa ...	2007	17216492
microtubule dynamics in root hairs of medicago truncatula.	the microtubular cytoskeleton plays an important role in the development of tip-growing plant cells, but knowledge about its dynamics is incomplete. in this study, root hairs of the legume medicago truncatula have been chosen for a detailed analysis of microtubular cytoskeleton dynamics using gfp-mbd and eb1-yfp as markers and 4d imaging. the microtubular cytoskeleton appears mainly to be composed of bundles which form tracks along which new microtubules polymerise. polymerisation rates of micro ...	2007	17218039
the lipopolysaccharide of sinorhizobium meliloti suppresses defense-associated gene expression in cell cultures of the host plant medicago truncatula.	in the establishment of symbiosis between medicago truncatula and the nitrogen-fixing bacterium sinorhizobium meliloti, the lipopolysaccharide (lps) of the microsymbiont plays an important role as a signal molecule. it has been shown in cell cultures that the lps is able to suppress an elicitor-induced oxidative burst. to investigate the effect of s. meliloti lps on defense-associated gene expression, a microarray experiment was performed. for evaluation of the m. truncatula microarray datasets, ...	2007	17220366
analysis of calcium spiking using a cameleon calcium sensor reveals that nodulation gene expression is regulated by calcium spike number and the developmental status of the cell.	rhizobium-made nod factors induce rapid changes in both ca(2+) and gene expression. mutations and inhibitors that abolish nod-factor-induced ca(2+) spiking block gene induction, indicating a specific role for ca(2+) spiking in signal transduction. we used transgenic medicago truncatula expressing a "cameleon" ca(2+) sensor to assess the relationship between nod-factor-induced ca(2+) spiking and the activation of downstream gene expression. in contrast to enod11 induction, ca(2+) spiking is activ ...	2006	17227545
an ire-like agc kinase gene, mtire, has unique expression in the invasion zone of developing root nodules in medicago truncatula.	the agc protein kinase family (camp-dependent protein kinases a, cgmp-dependent protein kinases g, and phospholipid-dependent protein kinases c) have important roles regulating growth and development in animals and fungi. they are activated via lipid second messengers by 3-phosphoinositide-dependent protein kinase coupling lipid signals to phosphorylation of the agc kinases. these phosphorylate downstream signal transduction protein targets. agc kinases are becoming better studied in plants, esp ...	2007	17237187
silencing of pr-10-like proteins in medicago truncatula results in an antagonistic induction of other pr proteins and in an increased tolerance upon infection with the oomycete aphanomyces euteiches.	recent studies on the root proteome of medicago truncatula (gaertn.) showed an induction of pathogenesis-related (pr) proteins of the class 10 after infection with the oomycete pathogen aphanomyces euteiches (drechs.). to get insights into the function of these proteins during the parasitic root-microbe association, a gene knockdown approach using rnai was carried out. agrobacterium rhizogenes-mediated transformation of m. truncatula roots led to a knockdown of the medicago pr10-1 gene in transg ...	2007	17237953
abscisic acid rescues the root meristem defects of the medicago truncatula latd mutant.	the latd gene of the model legume, medicago truncatula, is required for the normal function of three meristems, i.e. the primary root, lateral roots and nitrogen-fixing nodules. in latd mutants, primary root growth eventually arrests, resulting in a disorganized root tip lacking a presumptive meristem and root cap columella cells. lateral root organs are more severely affected; latd lateral roots and nodules arrest immediately after emerging from the primary root, and reveal a lack of organizati ...	2007	17239844
a medicago truncatula phosphate transporter indispensable for the arbuscular mycorrhizal symbiosis.	the arbuscular mycorrhizal (am) symbiosis is a mutualistic endosymbiosis formed by plant roots and am fungi. most vascular flowering plants have the ability to form these associations, which have a significant impact on plant health and consequently on ecosystem function. nutrient exchange is a central feature of the am symbiosis, and am fungi obtain carbon from their plant host while assisting the plant with the acquisition of phosphorus (as phosphate) from the soil. in the am symbiosis, the fu ...	2007	17242358
independent action and contrasting phenotypes of resistance genes against spotted alfalfa aphid and bluegreen aphid in medicago truncatula.	host resistance to aphids is poorly understood. medicago truncatula, a model legume and cultivated pasture species, was used to elucidate defense against two aphid species, therioaphis trifolii f. maculata (spotted alfalfa aphid, saa) and acyrthosiphon kondoi (bluegreen aphid, bga). aphid performance and plant damage were compared between near-isogenic cultivars, mogul and borung, that differ in resistance to both aphids. analyses of aphid resistance in mogul x borung f2 plants and their progeny ...	2007	17244058
involvement of the octadecanoid pathway in bluegreen aphid resistance in medicago truncatula.	aphids are major insect pests of plants that feed directly from the phloem. we used the model legume medicago truncatula gaert. (barrel medic) to elucidate host resistance to aphids and identified a single dominant gene which confers resistance to acyrthosiphon kondoi shinji (bluegreen aphid). to understand how this gene conditions resistance to bluegreen aphid, transcription profiling of 23 defense-related genes representing various signaling pathways was undertaken using a pair of near-isogeni ...	2007	17249425
roles of poly-3-hydroxybutyrate (phb) and glycogen in symbiosis of sinorhizobium meliloti with medicago sp.	poly-3-hydroxybutyrate (phb) and glycogen are major carbon storage compounds in sinorhizobium meliloti. the roles of phb and glycogen in rhizobia-legume symbiosis are not fully understood. glycogen synthase mutations were constructed by in-frame deletion (glga1) or insertion (glga2). these mutations were combined with a phbc mutation to make all combinations of double and triple mutants. phb was not detectable in any of the mutants containing the phbc mutation; glycogen was not detectable in any ...	2007	17259610
the mtmmpl1 early nodulin is a novel member of the matrix metalloendoproteinase family with a role in medicago truncatula infection by sinorhizobium meliloti.	we show here that mtmmpl1, a medicago truncatula nodulin gene previously identified by transcriptomics, represents a novel and specific marker for root and nodule infection by sinorhizobium meliloti. this was established by determining the spatial pattern of mtmmpl1 expression and evaluating gene activation in the context of various plant and bacterial symbiotic mutant interactions. the mtmmpl1 protein is the first nodulin shown to belong to the large matrix metalloendoproteinase (mmp) family. w ...	2007	17293436
characterization of resistance to multiple aphid species (hemiptera: aphididae) in medicago truncatula.	aphids are phloem-feeding insects that damage many important crops throughout the world yet, compared to plant-pathogen interactions, little is known about the mechanisms by which plants become resistant to aphids. medicago truncatula (barrel medic) is widely considered as the pre-eminent model legume for genetic and biological research and in australia is an important pasture species. six cultivars of m. truncatula with varying levels of resistance to two pests of pasture and forage legumes, th ...	2007	17298680
plant species, atmospheric co2 and soil n interactively or additively control c allocation within plant-soil systems.	two plant species, medicago truncatula (legume) and avena sativa (non-legume), were grown in low- or high-n soils under two co2 concentrations to test the hypothesis whether c allocation within plant-soil system is interactively or additively controlled by soil n and atmospheric co2 is dependent upon plant species. the results showed the interaction between plant species and soil n had a significant impact on microbial activity and plant growth. the interaction between co2 and soil n had a signi ...	2006	17313000
characterization of the interaction between the bacterial wilt pathogen ralstonia solanacearum and the model legume plant 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. solanacearum strains on the two m. truncatula lines, differential interactions were identified. r. solanacearum gmi1000 infected jemalong a17 line, and disease symptoms ...	2007	17313167
mastoparan activates calcium spiking analogous to nod factor-induced responses in medicago truncatula root hair cells.	the rhizobial-derived signaling molecule nod factor is essential for the establishment of the medicago truncatula/sinorhizobium meliloti symbiosis. nod factor perception and signal transduction in the plant involve calcium spiking and lead to the induction of nodulation gene expression. it has previously been shown that the heterotrimeric g-protein agonist mastoparan can activate nodulation gene expression in a manner analogous to nod factor activation of these genes and this requires doesn't ma ...	2007	17322338
genebins: a database for classifying gene expression data, with application to plant genome arrays.	to interpret microarray experiments, several ontological analysis tools have been developed. however, current tools are limited to specific organisms.	2007	17349060
identification of qtl for reaction to three races of colletotrichum trifolii and further analysis of inheritance of resistance in autotetraploid lucerne.	anthracnose, caused by colletotrichum trifolii, is one of the most serious diseases of lucerne worldwide. the disease is managed through deployment of resistant cultivars, but new pathotypes present a challenge to the successful implementation of this strategy. this paper reports the genetic map locations of quantitative trait loci (qtl) for reaction to races 1, 2 and 4 of c. trifolii in a single autotetraploid lucerne clone, designated w126 from the australian cv. trifecta. resistance was mappe ...	2007	17356866