Presymbiotic factors released by the arbuscular mycorrhizal fungus Gigaspora margarita induce starch accumulation in Lotus japonicus roots.

* Nutrient exchange is the key symbiotic feature of arbuscular mycorrhiza (AM). As evidence is accumulating that plants sense presymbiotic factors from AM fungi and prepare for colonization, we investigated whether modifications in plant sugar metabolism might be part of the precolonization program. * Inoculation of Lotus japonicus roots in a double Millipore sandwich with the AM fungus Gigaspora margarita prevented contact between the symbionts but allowed exchange of signal molecules.

Global changes in transcription orchestrate metabolic differentiation during symbiotic nitrogen fixation in Lotus japonicus.

Research on legume nodule metabolism has contributed greatly to our knowledge of primary carbon and nitrogen metabolism in plants in general, and in symbiotic nitrogen fixation in particular. However, most previous studies focused on one or a few genes/enzymes involved in selected metabolic pathways in many different legume species. We utilized the tools of transcriptomics and metabolomics to obtain an unprecedented overview of the metabolic differentiation that results from nodule development in the model legume, Lotus japonicus.