| Title: | Grapevine fatty acid hydroperoxide lyase generates actin-disrupting volatiles and promotes defence-related cell death |
| Author(s): | Akaberi S; Wang H; Claudel P; Riemann M; Hause B; Hugueney P; Nick P; |
| Address: | "Molecular Cell Biology, Botanical Institute, Karlsruhe Institute of Technology, Fritz-Haber-Weg, Building, Karlsruhe, Germany. Joint research unit for grapevine health and wine quality (SVQV), INRA, Universite de Strasbourg, Colmar, France. Cell and Metabolic Biology, Leibniz Institute of Plant Biochemistry (IPB), Weinberg, Halle (Saale), Germany" |
| ISSN/ISBN: | 1460-2431 (Electronic) 0022-0957 (Print) 0022-0957 (Linking) |
| Abstract: | "Fatty acid hydroperoxides can generate short-chained volatile aldehydes that may participate in plant defence. A grapevine hydroperoxide lyase (VvHPL1) clustering to the CYP74B class was functionally characterized with respect to a role in defence. In grapevine leaves, transcripts of this gene accumulated rapidly to high abundance in response to wounding. Cellular functions of VvHPL1 were investigated upon heterologous expression in tobacco BY-2 cells. A C-terminal green fluorescent protein (GFP) fusion of VvHPL1 was located in plastids. The overexpression lines were found to respond to salinity stress or the bacterial elicitor harpin by increasing cell death. This signal-dependent mortality response was mitigated either by addition of exogenous jasmonic acid or by treatment with diphenyleneiodonium (DPI), an inhibitor of NADPH oxidases. By feeding different substrates to recombinantly expressed enzyme, VvHPL1 could also be functionally classified as true 13-HPL. The cognate products generated by this 13-HPL were cis-3-hexenal and trans-2-hexenal. Using a GFP-tagged actin marker line, one of these isomeric products, cis-3-hexenal, was found specifically to elicit a rapid disintegration of actin filaments. This response was not only observed in the heterologous system (tobacco BY-2), but also in a grapevine cell strain expressing this marker, as well as in leaf discs from an actin marker grape used as a homologous system. These results are discussed in the context of a role for VvHPL1 in a lipoxygenase-dependent signalling pathway triggering cell death-related defence that bifurcates from jasmonate-dependent basal immunity" |
| Keywords: | Actins/*metabolism Aldehyde-Lyases/*genetics/metabolism Cell Death/*physiology Cytochrome P-450 Enzyme System/*genetics/metabolism Plant Leaves/metabolism Plant Proteins/*genetics/metabolism Vitis/genetics/*physiology Volatile Organic Compounds/*metabolis; |
| Notes: | "MedlineAkaberi, Sahar Wang, Hao Claudel, Patricia Riemann, Michael Hause, Bettina Hugueney, Philippe Nick, Peter eng Research Support, Non-U.S. Gov't England 2018/04/17 J Exp Bot. 2018 May 25; 69(12):2883-2896. doi: 10.1093/jxb/ery133" |
