@article {Goupil145425, author = {Pascale Goupil and Razik Benouaret and Claire Richard}, title = {Alkyl gallates display elicitor activities in tobacco plants}, elocation-id = {145425}, year = {2017}, doi = {10.1101/145425}, publisher = {Cold Spring Harbor Laboratory}, abstract = {Alkyl gallates showed elicitor activities on tobacco in both whole plants and cell suspensions. Methyl gallate (MG), ethyl gallate (EG) and n-propyl gallate (PG) infiltration into tobacco leaves induced hypersensitive reaction-like lesions and topical production of autofluorescent compounds revealed under UV light. When sprayed on tobacco plants at 5 mM, EG promoted upregulation of defence-related genes such as the antimicrobial PR1, β-1,3-glucanase PR2, chitinase PR3 and osmotin PR5 target genes. Tobacco BY-2 cells challenged with EG underwent cell death in 48 h, significantly reduced in the presence of the protease inhibitor aprotinin. The three alkyl gallates all caused alkalinisation of the BY-2 extracellular medium, whereas gallic acid did not trigger any pH variation. Using EGTA or LaCl3, we showed that Ca2+ mobilisation occurred in BY-2 cells elicited with EG. Overall, our findings are the first evidence of alkyl gallate elicitor properties with early perception events on plasma membrane, potential hypersensitive reactions and PR-related downstream defence responses in tobacco.Highlights{\textendash} Alkyl gallates elicited defence reactions in tobacco{\textendash} Alkyl gallates induced local biochemical changes in tobacco leaves{\textendash} Alkyl gallates caused modification of plasma membrane properties{\textendash} Ethyl gallate led to defence transcript accumulation and dose-dependent cell death associated with hypersensitive response{\textendash} Alkyl gallates are novel elicitor agents well-suited to crop protection schemes.}, URL = {https://www.biorxiv.org/content/early/2017/06/02/145425}, eprint = {https://www.biorxiv.org/content/early/2017/06/02/145425.full.pdf}, journal = {bioRxiv} }