Early production and scavenging of hydrogen peroxide in the apoplast of sunflower plants exposed to ozone
The present work set out to define the processes involved in the early O3-induced H2O2 accumulation in sunflower plants exposed to a single pulse of 150 ppb of O3 for 4 h. Hydrogen peroxide accumulation only occurred in the apoplast and this temporally coincided with the fumigation period. The inhib...
Veröffentlicht in: | Journal of experimental botany. - 1985. - 54(2003), 392 vom: 01. Nov., Seite 2529-40 |
---|---|
1. Verfasser: | |
Weitere Verfasser: | , , , , |
Format: | Aufsatz |
Sprache: | English |
Veröffentlicht: |
2003
|
Zugriff auf das übergeordnete Werk: | Journal of experimental botany |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Free Radical Scavengers Thiobarbituric Acid Reactive Substances Ozone 66H7ZZK23N Hydrogen Peroxide BBX060AN9V NADH, NADPH Oxidoreductases EC 1.6.- mehr... |
Zusammenfassung: | The present work set out to define the processes involved in the early O3-induced H2O2 accumulation in sunflower plants exposed to a single pulse of 150 ppb of O3 for 4 h. Hydrogen peroxide accumulation only occurred in the apoplast and this temporally coincided with the fumigation period. The inhibitor experiments suggested that both the plasma membrane-bound NAD(P)H oxidase complex and cell-wall NAD(P)H PODs contributed to H2O2 generation. To investigate the mechanisms responsible for O3-induced H2O2 accumulation further, both production and scavenging of H2O2 were investigated in the extracellular matrix after subcellular fractionation. The results indicated that H2O2 accumulation is a complex and highly regulated event requiring the time-dependent stimulation and down-regulation of differently located enzymes, some of which are involved in H2O2 generation and degradation, not only during the fumigation period but also in the subsequent recovery period in non-polluted air. Owing to the possible interplay between H2O2 and ethylene, the time-course of ethylene emission was analysed too. Ethylene was rapidly emitted following O3 exposure, but it declined to control values as early as after 4 h of exposure. The early contemporaneous detection of increased ethylene and H2O2 levels after 30 min of exposure does not allow a clear temporal relationship between these two signalling molecules to be established |
---|---|
Beschreibung: | Date Completed 21.01.2004 Date Revised 16.11.2017 published: Print-Electronic Citation Status MEDLINE |
ISSN: | 0022-0957 |