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).
Project description:In order to better understand the commonalities and differences in lateral root and nodule development, we compared their organogenesis and correlated this with changes in gene expression. To initiate lateral roots in Medicago truncatula we turned 2-day-old seedlings 135°, before returning them to their original axis of growth, while for nodule initiation we applied droplets of Sinorhizobium meliloti on the susceptibility zone of the root.
Project description:We studied potentially amyloidogenic proteins (e.g. protein forming polymers and complexes that are resistant to treatment with ionic detergents) in root nodules formed by two lines of garden pea (P. sativum L.): Sprint-2 (Fix+ phenotype) and Sprint-2Fix- (sym31) (Fix- phenotype) inoculated with the Rhizobium leguminosarum bv. viciae RCAM1026 root nodule bacteria. The Fix+ phenotype is characterized by effective (ability to fix nitrogen) root nodules formation. The Fix- line is a descendant of the Fix+ line and forms ineffective root nodules (unable to fix nitrogen) with undifferentiated bacteroids. We demonstrated the presence of both plant and bacterial proteins in detergent resistant fractions, including previously identified amyloid proteins RopA and RopB of R. leguminosarum and vicilin of P. sativum L.