Role of polyamines and ethylene as modulators of plant senescence

@article{Pandey2007RoleOP,
  title={Role of polyamines and ethylene as modulators of plant senescence},
  author={Subedar Pandey and S. A. Ranade and Pramod Kumar Nagar and Nikhil Ram Kumar},
  journal={Journal of Biosciences},
  year={2007},
  volume={25},
  pages={291-299}
}
Under optimal conditions of growth, senescence, a terminal phase of development, sets in after a certain physiological age. It is a dynamic and closely regulated developmental process which involves an array of changes at both physiological and biochemical levels including gene expression. A large number of biotic and abiotic factors accelerate the process. Convincing evidence suggests the involvement of polyamines (PAs) and ethylene in this process. Although the biosynthetic pathways of both… 
The Role of Growth Regulators in Senescence
Senescence: Regulation and Signalling
TLDR
The environmental stress factors such as drought, water logging, high or low solar radiation, extreme temperatures, ozone and other air pollutants, and excessive soil salinity, besides inadequate mineral nutrition in soil, negatively influence the senescence.
Polyamine Metabolism Responses to Biotic and Abiotic Stress.
TLDR
This chapter reviewed the information available till date in relation to the roles played by polyamines in the responses of plants during biotic and abiotic stress and demonstrated that a fine-tuned regulation of the enzymes involved in the biosynthesis and catabolism of polyamines leads to the increment in the concentration of these compounds.
Roles of Some Plant Growth Regulators on Natural and Dark-Induced Senescence in Wheat Leaf Segments
TLDR
It is concluded that Spm and Spd could promote senescence on wheat segments under light conditions, whereas inhibition under dark conditions, and BA could retard the deleterious effects onsenescence under both light and dark conditions.
Polyamine catabolism adds fuel to leaf senescence
TLDR
Recent molecular, physiological, and biochemical evidence implicating concurrently polyamines and ethylene in dark-induced leaf senescence is summarized, broadening knowledge on the mechanistic events involved in this important plant death process.
Transcriptional Modulation of Polyamine Metabolism in Fruit Species Under Abiotic and Biotic Stress
TLDR
Data on polyamine synthesis and catabolism in fruit related to pre- and postharvest stresses is explored to indicate that these growth regulators can be manipulated to increase fruit productivity with reduced use of pesticides and therefore, under more sustainable conditions.
Flower Senescence-Strategies and Some Associated Events
TLDR
The review recommends that more elaborate work is required at cellular and organelle level to understand the ethylene-independent pathway and its execution in both Ethylene-sensitive andEthylene-insensitive flower systems and that ethylene sensitivity should not be generally assigned to plants at the family level on the basis of response of a few species in a family.
Polyamines: molecules with regulatory functions in plant abiotic stress tolerance
TLDR
The integration of polyamines with other metabolic pathways is discussed by focusing on molecular mechanisms of their action in abiotic stress tolerance by integrating with processes of reactive oxygen species (ROS) signalling, generation of nitric oxide, modulation of ion channel activities and Ca2+ homeostasis.
Plastid-associated polyamines: their role in differentiation, structure, functioning, stress response and senescence.
TLDR
The occurrence of polyamines and enzymes participating in their metabolism at every stage of plastid development indicates that polyamines play a role inPlastid differentiation, structure, functioning and senescence.
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 109 REFERENCES
The molecular biology of leaf senescence
TLDR
Experiments with transgenic plants and mutants are already shedding light on the role played by cytokinins and ethylene in regulating senescence in leaves, and analysis of the regulatory mechanisms controlling the expression ofSenescence-induced genes will allow the signalling pathways that are involved in the regulation of senescences to be elucidated.
Ethylene and flower petal senescence: Interrelationship with membrane lipid catabolism
TLDR
The results suggest an active role for lipid metabolites like DAG in enhancing flower senescence, through regulation of ethylene production and action, or possible activation of kinases, rather than a trigger of the process.
Ethylene and flower senescence
TLDR
Examination of other flowers shows that the carnation is not a universal paradigm for flower senescence, and the response to ethylene varies widely, and in many species petal wilting occurs without any apparent involvement of ethylene.
Ethylene biosynthesis and action: a case of conservation
TLDR
Interestingly, ethylene has also been shown to have opposite effects in some plants; for instance, it inhibits stem elongation in most dicots, whereas in some aquatic dicot and rice, it stimulates growth.
Antisense gene that inhibits synthesis of the hormone ethylene in transgenic plants
TLDR
It is shown that antisense RNA, which has previously been used only to reduce the expression of genes of known function when applied to pTOM13, reduces ethylene synthesis in a gene dosage-dependent manner.
Conjugated polyamines and reproductive development: Biochemical, molecular and physiological approaches
TLDR
The results suggest that male sterility is associated with catabolic processes exerted at the level of water-insoluble amine conjugates and support the view that diamine oxidase may be involved in the regulation of the amine concentration during sexual differentiation.
Ethylene regulates the timing of leaf senescence in Arabidopsis
TLDR
The leaves in etr1-1 functionally senesced even though the apparent life span of the leaf was prolonged, and in wild-type plants, exogenous ethylene was able to further accelerate induction of SAGs and decrease expression of PAGs.
Ethylene and fruit ripening
TLDR
Evidence suggesting that the NR ethylene perception and transduction pathway is specific to a defined set of genes expressed in ripening climacteric fruit and that a distinct ETR pathway regulates other ethylene-regulated genes in both immature and ripening Climacteric Fruit as well as in non-climacteric fruits is discussed.
Polyamines: Small Molecules Triggering Pathways in Plant Growth and Development
TLDR
Over the years polyamines have been implicated in being involved in a wide array of processes in plants, ranging from triggering organogenesis to protecting against stress, but their exact role has yet to be firmly established.
Developmental and age-related processes that influence the longevity and senescence of photosynthetic tissues in arabidopsis.
TLDR
It is postulated that leaf senescence is triggered by age-related declines in photosynthetic processes, which is consistent with a role for the product of this gene in nitrogen salvage.
...
1
2
3
4
5
...