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bioRxiv · 10.1101/740043

Symbiotic signalling is at the core of an endophytic Fusarium solani-legume association

Skiada, V.·Avramidou, M.·Bonfante, P.·Genre, A.·PAPADOPOULOU, K.
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Abstract

Legumes interact with a wide range of microbes in their root system, ranging from beneficial symbionts to pathogens. Symbiotic rhizobia and arbuscular mycorrhizal glomeromycetes trigger a so-called common symbiotic signalling pathway (CSSP), including the induction of nuclear calcium spiking in the root epidermis. In our study, the recognition of an endophytic Fusarium solani strain K in Lotus japonicus induced the expression of LysM receptors for chitin-based molecules, CSSP members and CSSP-dependent genes in L. japonicus. In LysM and CSSP mutant/RNAi lines, root penetration and fungal intraradical progression was either stimulated or limited while FsK exudates are perceived in a CSSP-dependent manner, triggering nuclear calcium spiking in epidermal cells of Medicago truncatula Root Organ Cultures. Our results corroborate that the CSSP is a more common pathway than previously envisaged, involved in the perception of signals from other microbes beyond the restricted group of symbiotic interactions sensu stricto.

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Skiada, V., Avramidou, M., Bonfante, P., Genre, A., PAPADOPOULOU, K.. 2019-08-20. Symbiotic signalling is at the core of an endophytic Fusarium solani-legume association. https://doi.org/10.1101/740043

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