Response of aspen cell cultures fed piperonylic acid to methyl jasmonate.

To better understand the role of phenylpropanoid pathway perturbation in plant metabolism, Populus tremuloides cell cultures previously established from leaf mesophyll tissue were fed with piperonylic acid (PIP) alone, or in combination with methyl jasmonate (MJ_PIP) approximately 5 days after transfer to fresh medium. Methyl jasmonate is an elicitor that activates a suite of defense responses including phenylpropanoid metabolism, while PIP acts as an inhibitor of cinnamate-4-hydroxylase (C4H). Sample tissues were contemporary with those used to generate Series GSE16773. Samples were harvested 48 hrs after initiation of the experiment. Total RNA was extracted and gene expression measured using Affymetrix poplar genome microarrays. Populus tremuloides cells suspended in liquid culture were fed with piperonylic acid dissolved in DMSO (PIP) either alone or in combination with methyl jasmonate in DMSO (MJ). Two replicates of total RNA were utilized for microarray analysis from a total of six or seen replicates produced per treatment condition.