Disease relevance of Medicago

• A glutamine synthetase gene from alfalfa (Medicago sativa) has been expressed in Escherichia coli after fusion of bacterial transcription and translation signals to a complete alfalfa glutamine synthetase coding sequence [1].
• Activation of the cell cycle machinery and the isoflavonoid biosynthesis pathway by active Rhizobium meliloti Nod signal molecules in Medicago microcallus suspensions [2].
• We have studied the presence and the expression of two pectic gene families in Medicago, polygalacturonases (PGs) and pectin methyl esterases (PMEs) during the early steps of the Sinorhizobium meliloti-Medicago interaction and compared them with related pollen-specific genes [3].
• Cell cycle function of a Medicago sativa A2-type cyclin interacting with a PSTAIRE-type cyclin-dependent kinase and a retinoblastoma protein [4].
• We show here that Rhizobium meliloti, the nitrogen-fixing endosymbiont of alfalfa (Medicago sativa), has a regulatory gene that is structurally homologous to previously characterized ntrC genes in enteric bacteria [5].

High impact information on Medicago

• Orthologues of h76p have been characterized in Drosophila and in the higher plant Medicago [6].
• Crystal structures of a multifunctional triterpene/flavonoid glycosyltransferase from Medicago truncatula [7].
• We present crystal structures of the UDP flavonoid/triterpene GT UGT71G1 from Medicago truncatula bound to UDP or UDP-glucose [7].
• Ethylene inhibits the Nod factor signal transduction pathway of Medicago truncatula [8].
• Using nodulation-defective mutants of Medicago truncatula, we have started to dissect the genetic control of Nod factor transduction [9].

Chemical compound and disease context of Medicago

• L-Canavanine made by Medicago sativa interferes with quorum sensing in Sinorhizobium meliloti [10].
• The Sinorhizobium meliloti ABC transporter Cho is highly specific for choline and expressed in bacteroids from Medicago sativa nodules [11].
• In Sinorhizobium meliloti, which can form a nitrogen-fixing root nodule symbiosis with Medicago spp., PC can be formed by two entirely different biosynthetic pathways, either the PE methylation pathway or the recently discovered PC synthase pathway [12].
• In addition, we have constructed a guaB mutant derived from Sinorhizobium meliloti 1021, and shown that, unlike R. tropici, the guaB S. meliloti mutant is auxotrophic for guanine and induces wild-type nodules on alfalfa and Medicago truncatula [13].
• From a pool of Medicago truncatula mutants--obtained by gamma-irradiation or ethyl methanesulfonate mutagenesis--impaired in symbiosis with the N-fixing bacterium Sinorhizobium meliloti, new mutants are described and genetically analysed, and for already reported mutants, complementary data are given on their phenotypic and genetic analysis [14].

Biological context of Medicago

• cDNA clones containing sequence similarity to the multifunctional vertebrate protein disulfide-isomerase (PDI, EC 5.3.4.1) were isolated from an alfalfa (Medicago sativa L.) cDNA library by screening with a cDNA sequence encoding human PDI [15].
• Culturing leaf protoplast-derived cells of the embryogenic alfalfa (Medicago sativa subsp. varia A2) genotype in the presence of low (1 microM) or high (10 microM) 2, 4-dichlorophenoxyacetic acid (2,4-D) concentrations results in different cell types [16].
• Proteomic analysis of somatic embryogenesis in Medicago truncatula. Explant cultures grown under 6-benzylaminopurine and 1-naphthaleneacetic acid treatments [17].
• Ethyl methanesulfonate mutagenesis of the model legume Medicago truncatula has previously identified several genes required for early steps in nodulation [18].
• 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) [19].

Anatomical context of Medicago

• Expression of the plastid-located glutamine synthetase of Medicago truncatula. Accumulation of the precursor in root nodules reveals an in vivo control at the level of protein import into plastids [20].
• G-protein from Medicago sativa: functional association to photoreceptors [21].
• Stress responses in alfalfa (Medicago sativa L.). 8. Cis-elements and trans-acting factors for the quantitative expression of a bean chalcone synthase gene promoter in electroporated alfalfa protoplasts [22].
• We further examined nematode feeding sites for the expression of two genes involved in nodule formation, ccs52 (encodes a mitotic inhibitor) and ENOD40 (encodes an early, nodulation mitogen), and found transcripts of both genes to be present in and around giant cells induced in Medicago [23].
• Oxygen consumption and Na+,K+-ATPase(EC 3.6.1.3)-dependent (ouabain-sensitive) and -independent respiration were measured for duodenal mucosa biopsies from 10-month-old sheep given two levels of digestible energy (DE) intake (7.6-7.7 and 14.8 MJ lucerne (Medicago sativa) pellets/d) and following 48 h of starvation [24].

Associations of Medicago with chemical compounds

• In aqueous solution, Medicago savita chalcone isomerase (CHI) enhances the reaction rate for the unimolecular rearrangement of chalcone (CHN) into flavanone by seven orders of magnitude [25].
• Chalcone O-methyltransferase (ChOMT) and isoflavone O-methyltransferase (IOMT) are S-adenosyl-l-methionine (SAM) dependent plant natural product methyltransferases involved in secondary metabolism in Medicago sativa (alfalfa) [26].
• There is strong evidence for a palaeoduplication event that affected both Glycine (a millettioid) and Medicago (from the IRL clade) [27].
• Conversion of vestitone to medicarpin in alfalfa (Medicago sativa L.) is catalyzed by two independent enzymes. Identification, purification, and characterization of vestitone reductase and 7,2'-dihydroxy-4'-methoxyisoflavanol dehydratase [28].
• We report the isolation and purification of a 42.98-kDa latex glycoprotein showing homology to the early nodule-specific protein (ENSP) of the legumes Medicago sativa, Medicago truncatula, and Glycine max [29].

Gene context of Medicago

• Previously, two cdc2 homologs, cdc2MsA and cdc2MsB, have been identified in alfalfa (Medicago sativa) [30].
• We have isolated a cDNA clone (cdc2Ms) from alfalfa (Medicago sativa L.) that is homologous to the yeast cdc2/CDC28 genes [31].
• Furthermore, our data show that addition of the Medicago CDKC;1-CYCT;1 heterodimer completely restored the transcriptional activity of a HeLa nuclear extract depleted of endogeneous CDK9 kinase complexes [32].
• The translated sequence of the cDNA has significant percent identity to Xenopus laevis nucleolin (31%), the alfalfa (Medicago sativa) nucleolin homolog (66%), and the yeast (Saccharomyces cerevisiae) nucleolin homolog (NSR1) (28%) [33].
• The 9.2-kb fragment complemented nodA-, nodB-, and nodC- mutants of R. meliloti to the Nod+ phenotype on Medicago sativa, M. truncatula, and Trigonella foenum-graecum [34].

Analytical, diagnostic and therapeutic context of Medicago

• We have cloned a SOMATIC EMBRYOGENESIS RECEPTOR KINASE (SERK) gene from Medicago truncatula (MtSERK1) and examined its expression in culture using real time PCR [35].
• In a second approach, microarray analysis was used to compare levels of alfalfa transcripts corresponding to 16,086 Medicago truncatula A17 genes in stems with and without trichomes [36].
• Immunolocalization and in situ hybridization experiments revealed that AO is preferentially expressed in the meristematic and the invasion zones in Medicago nodules and in the lateral meristematic zone of Lupinus nodules [37].
• Molecular cloning and expression of alfalfa (Medicago sativa L.) vestitone reductase, the penultimate enzyme in medicarpin biosynthesis [38].
• Application of immunodiffusion to the identification of Rhizobium meliloti strains competing for nodulation on Medicago sativa [39].

References