Project description:Arbuscular mycorrhiza (AM) interactions between plants and Glomeromycota fungi primarily support phosphate aquisition of most terrestrial plant species. To unravel gene expression during early stages of Medicago truncatula root colonization by AM fungi, we used genome-wide transcriptome profiling based on mycorrhizal root fragments enriched for early fungal infection stages. We used Medicago GeneChips to detail the global programme of gene expression in response to early stages of colonization by arbuscular mycorrhizal fungi and identified genes differentially expressed during these early stages.
Project description:We used laser-capture microdissection (LCM) to isolate specific cells from the Medicago truncatula nodule meristem (M), the distal infection (DIZ), the proximal infection zone (PIZ), infected cells (IC) and uninfected cells (UIC) from the fixation zone. Based on Medicago GeneChips, we identified the cell- and tissue-specific programm of gene expression in Medicago truncatula root nodules.
Project description:affy_ralstonia_medicago - Ralstonia solanacearum is the causal agent of the devastating bacterial wilt disease. Its infection process was studied with an in vitro inoculation procedure on intact roots of Medicago truncatula. The pathosystem involved susceptible A17 and resistant F83005.5 M truncatula lines infected with the pathogenic strain GMI1000. The mutant A17 line, Sickle, which showed a resistant phenotype was also part of the experiment. To identify host signaling pathway triggered by R. solanacearum infection with a focus on the involvment of ethylene, we used the Medicago Affymetrix array to monitore the expression profiles and the molecular process associated with initial symptoms development (12hpi) and colonization (72hpi). In order to maximize chances to observe differential gene expression, RNA samples were extracted from the root infection zone (root tips) -Three Medicago truncatula lines, A17, F83005.5 and sickle were inoculated with GMI1000 Ralstonai solanacearum strain (107 cfu/ml). RNA were extracted from root extremities (1 cm above the root tip) at time 0, 12h and 72h post inoculation. Three biological repeats were conducted
Project description:affy_ralstonia_peeters_medicago - We have identified two essential virulence determinants (GALA7, a type III secretion effector and HpaP, a chaperone-like protein) of Ralstonia solanacearum for the infection and colonisation of the host plant Medicago truncatula. The scope of this project is to identify the GALA7 and HpaP-specific transcriptome alteration. For this purpose wild type and mutant infected root material (13h and 72h postinfection) will be analysed on M. truncatula affymetrix chips. Medicago truncatula (A17 line) are grown in vitro on Farheus medium (with Nitrogen source) plantlets are inoculated with water R. solanacearum wt, gala7 and hpap mutants, and root tips are collected at 13h and 72h postinoculation. Experiment was performed 3 times independently. 4 bacteria conditions x 2 harvest times x 3 biological repeats = 24 samples Keywords: gene knock out,normal vs disease comparison,time course,treated vs untreated comparison
Project description:We have used deep sequencing of small RNAs from nodules and root apexes of the model legume Medicago truncatula, to identify 113 novel candidate miRNAs. These miRNAs (legume or Mt-specific) are encoded by 278 putative hairpin precursors in the M. truncatula genome. Several miRNAs are differentially expressed in nodules and root tips and large variety of targets could be predicted for these genes. Specific miRNA isoforms showed contrasting expression patterns in these tissues Keywords: Transcriptome analysis
