Delayed senescence of apple leaves by exogenous melatonin treatment: toward regulating the ascorbate–glutathione cycle
Top Cited Papers
- 12 October 2011
- journal article
- Published by Wiley in Journal of Pineal Research
- Vol. 53 (1), 11-20
- https://doi.org/10.1111/j.1600-079x.2011.00966.x
Abstract
The objectives of this study were to test the effects of exogenous melatonin on apple (Malus domestica Borkh. cv. Golden Delicious) leaves and investigate its possible physiological role in delaying leaf senescence. Detached leaves treated with 10 mm melatonin solutions clearly showed a slowing in their process of dark-induced senescence, as evidenced by both biochemical and molecular parameters. Melatonin delayed the normal reduction in chlorophyll content and maximum potential photosystem II efficiency (F(v) /F(m) ). It also suppressed the transcript levels of a key chlorophyll degradation gene, pheide a oxygenase (PAO), and the senescence-associated gene 12 (SAG12). This outcome was thought to be because of the enhanced antioxidant capabilities of melatonin. Indeed, H(2) O(2) accumulation was inhibited by exogenous melatonin, which might have resulted from direct reactive oxygen species scavenging by melatonin and a great enhancement of ascorbate peroxidase (APX; EC 1.11.1.11), which acted on both mRNA and protein activity levels. Melatonin treatment led to the maintenance of higher contents of ascorbic acid (AsA) and glutathione (GSH) but less dehydroascorbate (DHA) and oxidized glutathione (GSSG) compared with the control, possibly through its regulation of the AsA-GSH cycle.Keywords
This publication has 64 references indexed in Scilit:
- Melatonin improves the survival of cryopreserved callus of Rhodiola crenulataJournal of Pineal Research, 2010
- Sirtuins, melatonin and circadian rhythms: building a bridge between aging and cancerJournal of Pineal Research, 2009
- Rice NON-YELLOW COLORING1 Is Involved in Light-Harvesting Complex II and Grana Degradation during Leaf SenescenceTHE PLANT CELL ONLINE, 2007
- Melatonin promotes adventitious‐ and lateral root regeneration in etiolated hypocotyls of Lupinus albus L.Journal of Pineal Research, 2006
- Enhanced tolerance to ozone and drought stresses in transgenic tobacco overexpressing dehydroascorbate reductase in cytosolPhysiologia Plantarum, 2006
- High levels of melatonin in the seeds of edible plants: Possible function in germ tissue protectionLife Sciences, 2000
- Last exit: senescence, abscission, and meristem arrest in Arabidopsis.THE PLANT CELL ONLINE, 1997
- A simple and efficient method for isolating RNA from pine treesPlant Molecular Biology Reporter, 1993
- Free radical processes and loss of seed viability during desiccation in the recalcitrant species Quercus robur L.New Phytologist, 1992
- Ascorbate free radical reductase, a key enzyme of the ascorbic acid systemFEBS Letters, 1981