Pectin MethylEsterases (PME) catalyze the hydrolysis of the C6 galacturonic acid methylester group present in newly synthesized homogalacturonans. Analysis of recent literature suggests a potential role for pectin demethylesterification in the plant's response to nutritional stresses such as nitrogen and phosphorus or metal stresses such as cadmium and aluminum. This is evidenced by changes in PME activity under these conditions. These observations raise the question of whether pectin methylesterification is involved in the apoplastic transport and translocation of ions in both root and aerial plant tissues. The objective of this work is to provide direct evidence of such pectin-dependent apoplastic regulation of ion transport in plants. The response of wild-type Arabidopsis plants (Col0) to cadmium stress was evaluated. The impact of cadmium stress on the expression of all pectin methylesterase genes and modifications to the cell wall's composition was measured. Additionally, the impact of cadmium stress on two mutant lines will be investigated: cgr2cgr3, a double methyltransferase mutant, and gaut10gaut11, a double galacturonosyltransferase mutant. The goal is to assess how modifications to the cell wall pectic fraction impact the absorption and translocation of cadmium within the plant.