Análise evolutiva do sistems antioxidante gênico de Arabidopsis thaliana

Abstract

Reactive oxygen species (ROS) are byproducts of aerobic metabolism and may cause oxidative damage to biomolecules. Plants have a complex antioxidant system, involving enzymatic and non-enzymatic compounds, to protects against ROS exacerbated production. The evolutionary origin of enzymatic defense in plants is not totally clear. Here we describe an antioxidant gene network for A. thaliana and investigate the evolutionary origin of this network. We gathered from public repositories 208 A. thaliana genes directly involved with ROS detoxification and proposed an A. thaliana antioxidant gene network. Using orthology information of 238 Eukaryotes from STRINGdb we have inferred the evolutionary root of each gene to reconstruct the evolutionary history of A. thaliana antioxidant gene network. We found two interconnected clusters: one formed by SOD-related, Thiol-redox, and peroxidases; and other formed entirely by class III peroxidases. Each cluster emerged in different periods of evolution and class III peroxidases are the most recent components of the network. According to our results, class III peroxidases are in expansion throughout plant evolution.