Polyamines, auxins and organogenesis in leafy spurge (Euphorbia esula L.)

Abstract

Summary:Canaline and canavanine (inhibitors of polyamine biosynthesis) effects on root and shoot formation were determined in vitro for etiolated hypocotyl segments of leafy spurge (Euphorbia esula L.). Canaline (an ornithine analogue) at 10 to 100 µmol/L inhibited root and shoot formation. The simultaneous application of putrescine did not reverse canaline-induced inhibition of root formation. Ornithine, a precursor of putrescine via the ornithine decarboxylase pathway, unexpectedly inhibited root formation. Canavanine (an arginine analogue) at 30 to 100 µmol/L inhibited root and/or shoot formation. Inhibition of root formation by canavanine was not reversed by agmatine or putrescine, but was partially reversed by arginine. Indoleacetic acid (IAA) inhibited shoot formation, stimulated root formation, and partially reversed the inhibition of root formation by either canaline or canavanine. IAA generally increased endogenous levels of free polyamines in controls and canaline-or canavanine-treated tissues, but these changes were small and probably had little effect on organogenesis. IAA also partially reversed the inhibition of root (but not shoot) formation by arcaine and pentamidine, inhibitors of polyamine action in mammals. The roles of the polyamines in plants is not clear, but the polyamines may play only minor roles in root and shoot formation.

Biochemical activity of di- and polyamines in the green alga Chlorella vulgaris Beijerinck (Chlorophyceae)

“…It is well known that the physiological-biochemical activity of di-and polyamines is mainly due to their polycation structure. In all probability, the more number of amine groups in poliamine, the more metabolically active this compound is, because in this way it possesses greater biochemical possibilities to interact with nucleic acids, proteins, hormones and another metabolites characterised by regulating function (Van den Broeck et al 1994;Davis 1997;Tiburcio et al 1997;Laitinen et al 1998;Desideiro et al 1999;Kotzabasis et al 1999). From the studies carried out on the C. vulgaris it was seen that the highest biological activity of spermidine results from the fact that it contains three amine groups of a cation character whereas the lowest activity is noted in agmatine with only one -NH 2 group.…”

“…triphosphoinositol and diacylglycerol mainly by stimulating the synthesis of their direct precursors, the phosphoinositides. Their action within the cells is auxiliary and complementary to the effect of phytohormones and other regulators stimulating plant physiological-metabolic processes (Smith 1985;Bothma and Dubery 1991;Gniazdowska-Skoczek et al 1994;Ponappa and Miller 1996;Bagni 1997;Davis 1997;Sarjala et al 1997;Czerpak and Bajguz 1999).…”

Ecologically diverse and distinct neighbourhoods trigger persistent phenotypic consequences, and amine metabolic profiling detects them

“…The acetyl conjugate of putrescine N ‐acetylputrescine responded less but in an overall similar way. Agmatine is a growth regulator that is particularly involved in root formation and growth (Davis ; Hummel et al . ), and that correlates to increased cold tolerance (Paldi et al .…”

Canavanine Alters ROS/RNS Level and Leads to Post-translational Modification of Proteins in Roots of Tomato Seedlings

“…Some PTMs, e.g., carbonylation stimulate proteolytic degradation, therefore, we investigated impact of CAN on proteolytic activity. In addition, we linked CAN toxicity with the activity of polyamine oxidase (PAO) because decline of PAs content was observed as a result of CAN treatment ( Davis, 1997 ) and degradation of PAs leads to H 2 O 2 formation. NADPH oxidase catalyze the apoplastic production of , plant peroxidase Class III (POx) catalyzes oxidoreduction between H 2 O 2 and various reductants ( Hiraga et al, 2001 ; Kaur et al, 2014 ).…”