The roles of polyamines during the lifespan of plants: from development to stress

Abstract

Compelling evidence indicates that free polyamines (PAs) (mainly putrescine, spermidine, spermine, and its isomer thermospermine), some PA conjugates to hydroxycinnamic acids, and the products of PA oxidation (hydrogen peroxide and γ-aminobutyric acid) are required for different processes in plant development and participate in abiotic and biotic stress responses. A tight regulation of PA homeostasis is required, since depletion or overaccumulation of PAs can be detrimental for cell viability in many organisms. In plants, homeostasis is achieved by modulation of PA biosynthesis, conjugation, catabolism, and transport. However, recent data indicate that such mechanisms are not mere modulators of PA pools but actively participate in PA functions. Examples are found in the spermidine-dependent eiF5A hypusination required for cell division, PA hydroxycinnamic acid conjugates required for pollen development, and the involvement of thermospermine in cell specification. Recent advances also point to implications of PA transport in stress tolerance, PA-dependent transcriptional and translational modulation of genes and transcripts, and posttranslational modifications of proteins. Overall, the molecular mechanisms identified suggest that PAs are intricately coordinated and/or mediate different stress and developmental pathways during the lifespan of plants.

Salt acclimation processes in wheat

“…Polyamines are a group of aliphatic amines that are found in all living cells and appear to be essential for life (Minocha et al, 2014;Tiburcio et al, 2014). Their role in stress protection has been widely studied, including their possible involvement in salinity stress (Do et al, 2014).…”

Speculation: Polyamines are important in abiotic stress signaling

“…The total and individual polyamine contents vary markedly depending both on the plant species or organ and on the developmental stage, and are much higher in plants than those of endogenous phytohormones. The biosynthetic pathway and key enzymes of the polyamine metabolism are well documented [1]. Briefly, putrescine is synthesized by the decarboxylation of ornithine, catalysed by ornithine Polyamines were previously presumed to be simply direct protective compounds.…”

10th International Conference, Plant Functioning Under Environmental Stress, September 16-19, 2015, Cracow, Poland

“…Signal transduction as a result of JA-Me treatment, as well as molecular mechanism of regulation anthocyanins in roots of K. blossfeldiana remains unknown. In plants, polyamines participate in abiotic and biotic stress responses and play a protective role against these stresses (Tiburcio et al, 2014). It is also known that in plants polyamines are implicated in various physiological processes, including secondary metabolism (Tiburcio et al, 2014).…”