TY - JOUR
T1 - Biochemical characterization of the tomato phosphatidylinositol-specific phospholipase C (PI-PLC) family and its role in plant immunity
AU - Abd-El-Haliem, Ahmed M
AU - Vossen, Jack H
AU - van Zeijl, Arjan
AU - Dezhsetan, Sara
AU - Testerink, Christa
AU - Seidl, Michael F
AU - Beck, Martina
AU - Strutt, James
AU - Robatzek, Silke
AU - Joosten, Matthieu H A J
N1 - Copyright © 2016 Elsevier B.V. All rights reserved.
PY - 2016/9
Y1 - 2016/9
N2 - Plants possess effective mechanisms to quickly respond to biotic and abiotic stresses. The rapid activation of phosphatidylinositol-specific phospholipase C (PLC) enzymes occurs early after the stimulation of plant immune-receptors. Genomes of different plant species encode multiple PLC homologs belonging to one class, PLCζ. Here we determined whether all tomato homologs encode active enzymes and whether they can generate signals that are distinct from one another. We searched the recently completed tomato (Solanum lycopersicum) genome sequence and identified a total of seven PLCs. Recombinant proteins were produced for all tomato PLCs, except for SlPLC7. The purified proteins showed typical PLC activity, as different PLC substrates were hydrolysed to produce diacylglycerol. We studied SlPLC2, SlPLC4 and SlPLC5 enzymes in more detail and observed distinct requirements for Ca(2+) ions and pH, for both their optimum activity and substrate preference. This indicates that each enzyme could be differentially and specifically regulated in vivo, leading to the generation of PLC homolog-specific signals in response to different stimuli. PLC overexpression and specific inhibition of PLC activity revealed that PLC is required for both specific effector- and more general "pattern"-triggered immunity. For the latter, we found that both the flagellin-triggered response and the internalization of the corresponding receptor, Flagellin Sensing 2 (FLS2) of Arabidopsis thaliana, are suppressed by inhibition of PLC activity. Altogether, our data support an important role for PLC enzymes in plant defence signalling downstream of immune receptors. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner.
AB - Plants possess effective mechanisms to quickly respond to biotic and abiotic stresses. The rapid activation of phosphatidylinositol-specific phospholipase C (PLC) enzymes occurs early after the stimulation of plant immune-receptors. Genomes of different plant species encode multiple PLC homologs belonging to one class, PLCζ. Here we determined whether all tomato homologs encode active enzymes and whether they can generate signals that are distinct from one another. We searched the recently completed tomato (Solanum lycopersicum) genome sequence and identified a total of seven PLCs. Recombinant proteins were produced for all tomato PLCs, except for SlPLC7. The purified proteins showed typical PLC activity, as different PLC substrates were hydrolysed to produce diacylglycerol. We studied SlPLC2, SlPLC4 and SlPLC5 enzymes in more detail and observed distinct requirements for Ca(2+) ions and pH, for both their optimum activity and substrate preference. This indicates that each enzyme could be differentially and specifically regulated in vivo, leading to the generation of PLC homolog-specific signals in response to different stimuli. PLC overexpression and specific inhibition of PLC activity revealed that PLC is required for both specific effector- and more general "pattern"-triggered immunity. For the latter, we found that both the flagellin-triggered response and the internalization of the corresponding receptor, Flagellin Sensing 2 (FLS2) of Arabidopsis thaliana, are suppressed by inhibition of PLC activity. Altogether, our data support an important role for PLC enzymes in plant defence signalling downstream of immune receptors. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner.
KW - Arabidopsis/enzymology
KW - Arabidopsis Proteins/genetics
KW - Gene Expression Regulation, Plant
KW - Lycopersicon esculentum/enzymology
KW - Multigene Family
KW - Phosphoinositide Phospholipase C/biosynthesis
KW - Plant Immunity/genetics
KW - Protein Kinases/genetics
U2 - 10.1016/j.bbalip.2016.01.017
DO - 10.1016/j.bbalip.2016.01.017
M3 - Article
C2 - 26825689
SN - 0006-3002
VL - 1861
SP - 1365
EP - 1378
JO - Biochimica et Biophysica Acta
JF - Biochimica et Biophysica Acta
IS - 9 Pt B
ER -