Response of aspen cell cultures to combinatorial feeding of methyl jasmonate and AOPP.

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 methyl jasmonate, alpha-aminooxy-beta-phenylpropionic acid (AOPP), or both approximately 5 days after transfer to fresh medium. Methyl jasmonate is an elicitor that activates a suite of defense responses including phenylpropanoid metabolism. In contrast, AOPP acts as an inhibitor of phenylalanine ammonia lyase (PAL). 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 methyl jasmonate in DMSO (MJ), alpha-aminooxy-beta-phenylpropionic acid in DMSO (AOPP), each compound in DMSO (MJ_AOPP), or with DMSO alone (C). Two replicates of total RNA were utilized for microarray analysis from a total of six replicates generated per treatment.