Open AccessAtPME17 is a functional Arabidopsis thaliana pectin methylesterase regulated by its PRO region that triggers PME activity in the resistance to Botrytis cinerea
Author(s) -
Del Corpo Daniele,
Fullone Maria R.,
Miele Rossella,
Lafond Mickaël,
Pontiggia Daniela,
Grisel Sacha,
KiefferJaquinod Sylvie,
Giardina Thierry,
Bellincampi Daniela,
Lionetti Vincenzo
Publication year - 2020
Publication title -
molecular plant pathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.945
H-Index - 103
eISSN - 1364-3703
pISSN - 1464-6722
DOI - 10.1111/mpp.13002
Subject(s) - botrytis cinerea , arabidopsis thaliana , biology , jasmonic acid , pichia pastoris , pectin , biochemistry , pectinesterase , botrytis , escherichia coli , microbiology and biotechnology , botany , enzyme , recombinant dna , salicylic acid , mutant , gene , pectinase
Pectin is synthesized in a highly methylesterified form in the Golgi cisternae and partially de‐methylesterified in muro by pectin methylesterases (PMEs). Arabidopsis thaliana produces a local and strong induction of PME activity during the infection of the necrotrophic fungus Botrytis cinerea . AtPME17 is a putative A. thaliana PME highly induced in response to B. cinerea . Here, a fine tuning of AtPME17 expression by different defence hormones was identified. Our genetic evidence demonstrates that AtPME17 strongly contributes to the pathogen‐induced PME activity and resistance against B. cinerea by triggering jasmonic acid–ethylene‐dependent PDF1.2 expression. AtPME17 belongs to group 2 isoforms of PMEs characterized by a PME domain preceded by an N‐terminal PRO region. However, the biochemical evidence for AtPME17 as a functional PME is still lacking and the role played by its PRO region is not known. Using the Pichia pastoris expression system, we demonstrate that AtPME17 is a functional PME with activity favoured by an increase in pH. AtPME17 performs a blockwise pattern of pectin de‐methylesterification that favours the formation of egg‐box structures between homogalacturonans. Recombinant AtPME17 expression in Escherichia coli reveals that the PRO region acts as an intramolecular inhibitor of AtPME17 activity.