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bioRxiv · 10.1101/2021.10.14.464072

Hunting the plant surrender signal activating apoplexy in grapevines after Neofusicoccum parvum infection

Khattab, I. M.·Fischer, J.·Kazmierczak, A.·Thines, E.·Nick, P.
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Abstract

O_LIApoplectic breakdown from Grapevines Trunk Diseases (GTDs) has become a serious challenge to viticulture in consequence to drought stress. We hypothesise that fungal aggressiveness is controlled by a chemical communication between host and colonising fungus. C_LIO_LIWe introduce the new concept of a "plant surrender signal" accumulating in host plants under stress and triggering aggressive behaviour of the strain Neofusicoccum parvum (Bt-67) causing Botryosphaeriaceae-related dieback in grapevines. C_LIO_LIUsing a cell-based experimental system (Vitis cells) and bioactivity-guided fractionation, we identify trans-ferulic acid, a monolignol precursor, as "surrender signal". We show that this signal specifically activates secretion of the fungal phytotoxin Fusicoccin A. We show further that this phytotoxin, mediated by 14-3-3 proteins, activates programmed cell death in Vitis cells. C_LIO_LIWe arrive at a model pinpointing the chemical communication driving apoplexy in Botryosphaeriaceae-Vitis interaction and define the channelling of phenylpropanoid pathway from the lignin precursor, trans-ferulic acid to the phytoalexin transresveratrol as target for future therapy. C_LI

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Khattab, I. M., Fischer, J., Kazmierczak, A., Thines, E., Nick, P.. 2021-10-15. Hunting the plant surrender signal activating apoplexy in grapevines after Neofusicoccum parvum infection. https://doi.org/10.1101/2021.10.14.464072

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