Title: | Isoprene: An Antioxidant Itself or a Molecule with Multiple Regulatory Functions in Plants? |
Author(s): | Pollastri S; Baccelli I; Loreto F; |
Address: | "Institute for Sustainable Plant Protection (IPSP), The National Research Council of Italy (CNR), Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy. Department of Biology, The University of Naples Federico II, Via Cinthia, 80126 Naples, Italy" |
ISSN/ISBN: | 2076-3921 (Print) 2076-3921 (Electronic) 2076-3921 (Linking) |
Abstract: | "Isoprene (C(5)H(8)) is a small lipophilic, volatile organic compound (VOC), synthesized in chloroplasts of plants through the photosynthesis-dependent 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway. Isoprene-emitting plants are better protected against thermal and oxidative stresses but only about 20% of the terrestrial plants are able to synthesize isoprene. Many studies have been performed to understand the still elusive isoprene protective mechanism. Isoprene reacts with, and quenches, many harmful reactive oxygen species (ROS) like singlet oxygen ((1)O(2)). A role for isoprene as antioxidant, made possible by its reduced state and conjugated double bonds, has been often suggested, and sometimes demonstrated. However, as isoprene is present at very low concentrations compared to other molecules, its antioxidant role is still controversial. Here we review updated evidences on the function(s) of isoprene, and outline contrasting indications on whether isoprene is an antioxidant directly scavenging ROS, or a membrane strengthener, or a modulator of genomic, proteomic and metabolomic profiles (perhaps as a secondary effect of ROS removal) eventually leading to priming of antioxidant plant defenses, or a signal of stress for neighbor plants alike other VOCs, or a hormone-like molecule, controlling the metabolic flux of other hormones made by the MEP pathway, or acting itself as a growth and development hormone" |
Keywords: | defense priming hormones isoprenoids reactive oxygen species (ROS) signaling volatile organic compounds (VOCs); |
Notes: | "PubMed-not-MEDLINEPollastri, Susanna Baccelli, Ivan Loreto, Francesco eng Review Switzerland 2021/05/01 Antioxidants (Basel). 2021 Apr 27; 10(5):684. doi: 10.3390/antiox10050684" |