title: Overexpression of a pectin methylesterase inhibitor in Arabidopsis thaliana leads to altered growth morphology of the stem and defective organ separation.
abstract: The methylesterification status of cell wall pectins, mediated through the interplay of pectin methylesterases (PMEs) and pectin methylesterase inhibitors (PMEIs), influences the biophysical properties of plant cell walls. We found that the overexpression of a PMEI gene in Arabidopsis thaliana plants caused the stems to develop twists and loops, most strongly around points on the stem where leaves or inflorescences failed to separate from the main stem. Altered elasticity of the stem, underdevelopment of the leaf cuticle, and changes in the sugar composition of the cell walls of stems were evident in the PMEI overexpression lines. We discuss the mechanisms that potentially underlie the aberrant growth phenotypes.
authors.affiliation: Department of Biological Sciences; Simon Fraser University; Burnaby, BC Canada.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Müller
authors.affiliation: Department of Botany; University of British Columbia; Vancouver BC Canada.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Levesque-Tremblay
authors.affiliation: School of Physics and Astronomy; University of Nottingham; University Park; Nottingham, UK.
authors.forename: Anwesha
authors.initials: A
authors.lastname: Fernandes
authors.affiliation: Institute of Biology 1; RWTH Aachen; Aachen, Germany.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Wormit
authors.affiliation: Institute of Botany; University of Basel; Basel, Switzerland.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Bartels
authors.affiliation: Institute of Botany; University of Basel; Basel, Switzerland; Institute of Bio- and Geosciences; IBG-2: Plant Sciences; Forschungszentrum Jülich; Jülich, Germany.
authors.forename: Bjoern
authors.initials: B
authors.lastname: Usadel
authors.affiliation: Department of Biological Sciences; Simon Fraser University; Burnaby BC Canada.
authors.forename: Allison
authors.initials: A
authors.lastname: Kermode
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D002241:Carbohydrates / Q000032:analysis; D002265:Carboxylic Ester Hydrolases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D002473:Cell Wall / Q000378:metabolism; D009928:Organ Specificity; D010641:Phenotype; D019441:Plant Epidermis / Q000033:anatomy & histology / Q000254:growth & development; D018547:Plant Stems / Q000254:growth & development*; D030821:Plants, Genetically Modified
chemical_list: D029681:Arabidopsis Proteins; D002241:Carbohydrates; D002265:Carboxylic Ester Hydrolases; C022323:pectinesterase
keywords: Arabidopsis thaliana; cuticle integrity; organ separation; pectin methylesterification; stem growth