Mutation of AtPME2, a pH-Dependent Pectin Methylesterase, Affects Cell Wall Structure and Hypocotyl Elongation - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Plant and Cell Physiology Année : 2023

Mutation of AtPME2, a pH-Dependent Pectin Methylesterase, Affects Cell Wall Structure and Hypocotyl Elongation

Olivier Habrylo
Aline Voxeur
Serge Pilard
Arezki Boudaoud

Résumé

Pectin methylesterases (PMEs) modify homogalacturonan’s chemistry and play a key role in regulating primary cell wall mechanical properties. Here, we report on Arabidopsis AtPME2, which we found to be highly expressed during lateral root emergence and dark-grown hypocotyl elongation. We showed that dark-grown hypocotyl elongation was reduced in knock-out mutant lines as compared to the control. The latter was related to the decreased total PME activity as well as increased stiffness of the cell wall in the apical part of the hypocotyl. To relate phenotypic analyses to the biochemical specificity of the enzyme, we produced the mature active enzyme using heterologous expression in Pichia pastoris and characterized it through the use of a generic plant PME antiserum. AtPME2 is more active at neutral compared to acidic pH, on pectins with a degree of 55–70% methylesterification. We further showed that the mode of action of AtPME2 can vary according to pH, from high processivity (at pH8) to low processivity (at pH5), and relate these observations to the differences in electrostatic potential of the protein. Our study brings insights into how the pH-dependent regulation by PME activity could affect the pectin structure and associated cell wall mechanical properties.
Fichier non déposé

Dates et versions

hal-04406079 , version 1 (19-01-2024)

Licence

Copyright (Tous droits réservés)

Identifiants

Citer

Ludivine Hocq, Olivier Habrylo, Fabien Sénéchal, Aline Voxeur, Corinne Pau-Roblot, et al.. Mutation of AtPME2, a pH-Dependent Pectin Methylesterase, Affects Cell Wall Structure and Hypocotyl Elongation. Plant and Cell Physiology, 2023, ⟨10.1093/pcp/pcad154⟩. ⟨hal-04406079⟩
56 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More