The role of putrescine in the regulation of proteins and fatty acids of thylakoid membranes under salt stress

Abstract

Polyamines can alleviate the inhibitory effects of salinity on plant growth by regulating photosynthetic efficiency. However, little information is available to explain the specific mechanisms underlying the contribution of polyamines to salt tolerance of the photosynthetic apparatus. Here, we investigated the role of putrescine (Put) on the photosynthetic apparatus of cucumber seedlings under salt stress. We found that NaCl stress resulted in severe ion toxicity and oxidative stress in cucumber chloroplasts. In addition, salinity caused a significant increase in the saturated fatty acid contents of thylakoid membranes. Put altered unsaturated fatty acid content, thereby alleviating the disintegration of thylakoid grana lamellae and reducing the number of plastoglobuli in thylakoid membranes. BN-PAGE revealed Put up-regulated the expression of ATP synthase, CP47, D1, Qb, and psbA proteins and down-regulated CP24, D2, and LHCII type III in NaCl-stressed thylakoid membranes. qRT-PCR analysis of gene expression was used to compare transcript and protein accumulation among 10 candidate proteins. For five of these proteins, induced transcript accumulation was consistent with the pattern of induced protein accumulation. Our results suggest that Put regulates protein expression at transcriptional and translational levels by increasing endogenous polyamines levels in thylakoid membranes, which may stabilise photosynthetic apparatus under salt stress.

The arginine decarboxylase gene ADC1, associated to the putrescine pathway, plays an important role in potato cold‐acclimated freezing tolerance as revealed by transcriptome and metabolome analyses

“…Putrescine has been shown to be involved in plant response to abiotic tresses, such as mineral deficiency in Hordeum vulgare (Smith, ), osmotic shock in barley, corn, wheat, and wild oat (Flores and Galston, ), low pH and potassium deficiency in oat (Young and Galston, , ), salt stress in cucumber (Shu et al ., ), and cold stress in cucumber, chickpea, Arabidopsis (Shen et al ., ; Nayyar and Chander, ; Cuevas et al ., ). Putrescine is supposed to improve membrane stability under stress conditions (Farooq et al ., ; Benavides et al ., ).…”

“…Shu et al . () revealed that putrescine was implicated in altered unsaturated fatty acid content and alleviated damage to thylakoid membranes, in addition to stabilizing photosynthetic apparatus under salt stress. It is also demonstrated that putrescine plays a role in maintaining ROS homeostasis by regulating the antioxidant system to elevate abiotic stress tolerance (Liu et al ., ; Wang et al ., ; Song et al ., ).…”

Effects of exogenously applied plant growth regulators in combination with PGPR on the physiology and root growth of chickpea (Cicer arietinum) and their role in drought tolerance

“…Koc (2015) also reported the negative impacts of plant growth promoting bacteria and arbuscular mycorrhizal fungi on lipid peroxidation and total phenolics of strawberry when grown under stress condition. The exogenous application of SA and Put reduced the lipid peroxidation as compared to stress control (Sun et al 2013;Shu et al 2015). Noteworthy, the synergistic effect of PGR and PGPR was more pronounced.…”

Syringaldazine peroxidase stimulates lignification by enhancing polyamine catabolism in wheat during heat and drought stress

“…It was inferred that PAs acted as an antioxidant machinery to counteract oxidative stress produced under heat and drought stress. However, out of the three main polyamines (Put, Spd and Spm), Put seems to play a central role in stress tolerance due to its higher content and thus scavenges ROS leading to reduced oxidative damage as also observed by Shu et al (2015) under salt stress. It is generally believed that higher PAs can bind strongly to the negative charges in cellular components such as proteins and phospholipids and thereby stabilize the membranes under stress conditions (Asthir et al 2004;Liu et al 2007).…”