Both AtrbohD and AtrbohF are essential for mediating responses to oxygen deficiency in Arabidopsis.
Both AtrbohD and AtrbohF promote the increases in activities of ADH, PDC, LDH, and Ca2+levels, and induce the expression of multiple hypoxia response genes, thus improving Arabidopsis adaptation to oxygen deficiency. NADPH oxidase AtrbohD and AtrbohF cooperatively play key roles in regulation of growth and stress signaling in Arabidopsis. However, reports on AtrbohD and AtrbohF functioning together in hypoxia signaling are scarce, and the underlying mechanisms remain elusive. Here, we show that the double null mutant atrbohD/F is more sensitive to oxygen deprivation compared with wild type (WT) and the single mutant atrbohD and atrbohF. Under oxygen deficiency, enhancements of the transcripts of alcohol dehydrogenase 1 (ADH1) and pyruvate decarboxylase 1 (PDC1) and the activities of ADH, PDC and lactate dehydrogenase in WT are clearly reduced in the single mutants, and more strongly reduced in the double mutant. Moreover, increases in the production of ATP, H2O2and Ca2+in WT are significantly arrested in atrbohD, atrbohF, and especially in atrbohD/F. Hypoxia-promoted rise in the expression of some hypoxic responsive genes is also inhibited in atrbohD/F relative to WT, atrbohD and atrbohF. These genes include ethylene response factor 73, lactate dehydrogenase, MYB transcription factor 2, sucrose synthase 1 (SUS1), SUS4, heat stress transcription factor A2 and heat-shock protein 18.2. These results suggest that both AtrbohD and AtrbohF are essential for mediating hypoxia signaling. H2O2derived from AtrbohD and AtrbohF triggers the Ca2+increase and induces the expression of multiple hypoxia response genes, thus improving Arabidopsis tolerance to low-oxygen stress. These findings provide new insights into the mechanisms of AtrbohF in regulating the responses to oxygen deprivation in Arabidopsis.
State Key Laboratory of Cotton Biology, Henan Key Laboratory of Plant Stress Biology, College of Life Sciences, Henan University Jinming Campus, Kaifeng, 475004, China.|Department of Ecology, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China.
Bo
B
Liu
State Key Laboratory of Cotton Biology, Henan Key Laboratory of Plant Stress Biology, College of Life Sciences, Henan University Jinming Campus, Kaifeng, 475004, China.
Lirong
L
Sun
State Key Laboratory of Cotton Biology, Henan Key Laboratory of Plant Stress Biology, College of Life Sciences, Henan University Jinming Campus, Kaifeng, 475004, China.|Anci District Agricultural Bureau of Langfang, Langfang, 065000, China.
Liya
L
Ma
State Key Laboratory of Cotton Biology, Henan Key Laboratory of Plant Stress Biology, College of Life Sciences, Henan University Jinming Campus, Kaifeng, 475004, China. haofsh@henu.edu.cn.
Fu-Shun
FS
Hao
D000426:Alcohol Dehydrogenase / Q000378:metabolism; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism*; D011767:Pyruvate Decarboxylase / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology
D029681:Arabidopsis Proteins; D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide; D000426:Alcohol Dehydrogenase; D007770:L-Lactate Dehydrogenase; D011767:Pyruvate Decarboxylase; D010100:Oxygen; D002118:Calcium
Arabidopsis; AtrbohD; AtrbohF; Ca2+; H2O2; Hypoxia