Hypoxia-Responsive Class III Peroxidases in Maize Roots

Author(s)
Anne Hofmann, Stefanie Wienkoop, Sönke Harder, Fabian Bartlog, Sabine Lüthje
Abstract

Flooding induces low-oxygen environments (hypoxia or anoxia) that lead to energy disruption and an imbalance of reactive oxygen species (ROS) production and scavenging enzymes in plants. The influence of hypoxia on roots of hydroponically grown maize (Zea mays L.) plants was investigated. Gene expression (RNA Seq and RT-qPCR) and proteome (LC-MS/MS and 2D-PAGE) analyses were used to determine the alterations in soluble and membrane-bound class III peroxidases under hypoxia. Gel-free peroxidase analyses of plasma membrane-bound proteins showed an increased abundance of ZmPrx03, ZmPrx24, ZmPrx81, and ZmPr85 in stressed samples. Furthermore, RT-qPCR analyses of the corresponding peroxidase genes revealed an increased expression. These peroxidases could be separated with 2D-PAGE and identified by mass spectrometry. An increased abundance of ZmPrx03 and ZmPrx85 was determined. Further peroxidases were identified in detergent-insoluble membranes. Co-regulation with a respiratory burst oxidase homolog (Rboh) and key enzymes of the phenylpropanoid pathway indicates a function of the peroxidases in membrane protection, aerenchyma formation, and cell wall remodeling under hypoxia. This hypothesis was supported by the following: (i) an elevated level of hydrogen peroxide and aerenchyma formation; (ii) an increased guaiacol peroxidase activity in membrane fractions of stressed samples, whereas a decrease was observed in soluble fractions; and (iii) alterations in lignified cells, cellulose, and suberin in root cross-sections.

Organisation(s)
Functional and Evolutionary Ecology
External organisation(s)
Universitätsklinikum Hamburg-Eppendorf, Universität Hamburg
Journal
International Journal of Molecular Sciences
Volume
21
ISSN
1422-0067
DOI
https://doi.org/10.3390/ijms21228872
Publication date
11-2020
Peer reviewed
Yes
Austrian Fields of Science 2012
106008 Botany, 106023 Molecular biology
Portal url
https://ucris.univie.ac.at/portal/en/publications/hypoxiaresponsive-class-iii-peroxidases-in-maize-roots(1a012630-b428-4ec5-800a-d5cca4a0084f).html