Journal
PLANT SIGNALING & BEHAVIOR
Volume 14, Issue 11, Pages -Publisher
TAYLOR & FRANCIS INC
DOI: 10.1080/15592324.2019.1667730
Keywords
ADC; DAO; nitric oxide; ODC; PAO; polyamine; salt stress; SAMDC; spermine
Categories
Funding
- University Grants Commission (UGC) [2061530546, 21/06/2015(i)EU-V]
- UGC-ISF Joint Research Grant [6-9/2017 (IC)]
Ask authors/readers for more resources
Free polyamine (PA) titers in plants may be regulated through reversible conjugate formation and/or through modulation of their synthesis, transport and degradation. PA signaling involves the well-acknowledged signaling molecule, nitric oxide (NO), which functions in diverse biological processes. Present investigations demonstrate the influence of salt stress (120 mM NaCl) and exogenous NO donor (250 mu M Diethylenetriamine, DETA) on PA homeostasis of 2 d old, etiolated sunflower (Helianthus annuus L.) seedling cotyledons as a long-distance signaling response. Significantly enhanced intracellular spermine (Spm) accumulation was observed in seedling cotyledons under salt stress and in response to NO donor, the increase being more pronounced in seedlings treated with NO, evidently as a result of upregulation of the PA biosynthetic enzymes - arginine decarboxylase (ADC) and S-adenosylmethionine decarboxylase (SAMDC) - as revealed by Western blot and confocal imaging (CLSM). Moreover, salt stress induced the activity of polyamine oxidase (PAO), a PA catabolic enzyme, while NO lowered its activity in salt-stressed seedling cotyledons. NO, thus, appears to assist the seedlings in adapting to salt stress by positively regulating PA homeostasis through regulation of PA distribution between free, conjugated and bound forms, increased accumulation of PA biosynthetic enzymes and lowering the rate of PA catabolism.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available