Project description:12plex_medicago_2013-08 - r108 in symbiosis with rhizobia wt or rhizobia mutant for baca. - Two experiments to compare the transcriptomic response of medicago plants: Agar medium versus Phytagel medium (exp1) and rhizobium WT versus BacA (exp2). - Medicago truncatula ecotype R108 was inoculated with the symbiotic rhizobium Sinorhizobium meliloti strain Sm1021 and with its derivative mutant delta bacA. Nodules were collected 13 days after inoculation, and RNA were prepared for transcriptome analysis, there were three biological independant experiements. Overall design: rhizobium WT versus BacA. 3 dye-swap - gene knock out
Project description:To examine how the Arabidopsis root development responds to the Rhizobium sp. IRBG74 treatment at the molecular level, we performed RNA-seq experiments. Our RNA-seq results suggest that expression of genes mainly involved in auxin signaling, cell wall and cell membrane integrity and transport is altered in response to colonization by Rhizobium sp. IRBG74. Overall design: Examination of Arabidopsis roots treated by Rhizobium sp. IRBG74 for 24 and 48 hours.
Project description:12plex_medicago_2014_02 - nar nodule vs root transcriptome - which are the genes differentially expressed in alfalfa spontaneous (non rhizobium-infected) nodules vs. control roots? - biological material: aeroponically grown cuttings of a Medicago sativa (alfalfa) accession that produces empty nodules when nitrogen-starved. Samples for transcriptome comparison: isolated NAR nodules (10 days post N-starvation) vs. roots of the same plants (pools of 3 roots). Overall design: 4 dye-swap - organ comparison
Project description:Rhizobium leguminosarum biovar viciae strain 3841 was inoculated onto Viccia cracca seeds and bacteroids were harvested at 28d. Gene expression was then compared to free-living Rhizobium leguminosarum biovar viciae strain 3841 grown on succinate ammonia AMS.
Project description:For identification of plant gene networks which interact to initiate and support both rhizobial nodulation and AM fungal colonization, the transcription profiles of soybean genes induced during rhizobial, AM and their dual symbioses. Overall design: Four different treatments were used: an uninoculated control, inoculation with rhizobium alone (rhizobial symbiosis), inoculation with AM fungus alone (AM symbiosis), and inoculation with rhizobium and AM fungus together (dual symbiosis). After the soybeans inoculated were grown in a glasshouse for 6 weeks, the transcriptome of host genes were analyzed using a cDNA microarray
Project description:Coevolutionary change requires reciprocal selection between interacting species, i.e., that the partner genotypes that are favored in one species depend on the genetic composition of the interacting species. Coevolutionary genetic variation is manifested as genotype ´ genotype (G ´ G) interactions for fitness from interspecific interactions. Although quantitative genetic approaches have revealed abundant evidence for G ´ G interactions in symbioses, the molecular basis of this variation remains unclear. Here we study the molecular basis of G ´ G interactions in a model legume-rhizobium mutualism using gene expression microarrays. We find that, like quantitative traits such as fitness, variation in the symbiotic transcriptome may be partitioned into additive and interactive genetic components. Our results suggest that plant genetic variation is the largest influence on nodule gene expression, and that plant genotype and the plant genotype ´ rhizobium genotype interaction determine global shifts in rhizobium gene expression that in turn feedback to influence plant fitness benefits. Moreover, the transcriptomic variation we uncover implicates regulatory changes in both species as drivers of symbiotic gene expression variation. Our study is the first to partition genetic variation in a symbiotic transcriptome, and illuminates potential molecular routes of coevolutionary change. We assayed gene expression using three biological replicates for each plant genotype × rhizobium genotype combination (4 combinations) for a total of 12 chips. We compared gene expression in each of four combinations of Medicago truncatula families and Sinorhizobium meliloti strains using Affymetrix Medicago GeneChips to study how the entire transcriptome and individual genes responded to differences between plant families, between rhizobium strains, and due to the plant family × rhizobium strain (G × G) interaction.