Membrane Lipid Remodeling in Response to Salinity

Abstract

Salinity is one of the most decisive environmental factors threatening the productivity of crop plants. Understanding the mechanisms of plant salt tolerance is critical to be able to maintain or improve crop yield under these adverse environmental conditions. Plant membranes act as biological barriers, protecting the contents of cells and organelles from biotic and abiotic stress, including salt stress. Alterations in membrane lipids in response to salinity have been observed in a number of plant species including both halophytes and glycophytes. Changes in membrane lipids can directly affect the properties of membrane proteins and activity of signaling molecules, adjusting the fluidity and permeability of membranes, and activating signal transduction pathways. In this review, we compile evidence on the salt stress responses of the major membrane lipids from different plant tissues, varieties, and species. The role of membrane lipids as signaling molecules in response to salinity is also discussed. Advances in mass spectrometry (MS)-based techniques have largely expanded our knowledge of salt-induced changes in lipids, however only a handful studies have investigated the underlying mechanisms of membrane lipidome regulation. This review provides a comprehensive overview of the recent works that have been carried out on lipid remodeling of plant membranes under salt treatment. Challenges and future perspectives in understanding the mechanisms of salt-induced changes to lipid metabolisms are proposed.

Site-Specific Lipidomic Signatures of Sea Lettuce (Ulva spp., Chlorophyta) Hold the Potential to Trace Their Geographic Origin

“…The salinity level variability of both the Sado Estuary [62] and Ria de Aveiro [63,64] has been studied, both reflecting the influence of existing saltpans. The role of membrane lipids as signaling molecules in response to salinity can herein play a role [19,65]. Salinity-induce shifts in membrane lipids that include changes on the content of lipids, fatty acid unsaturation level, and fatty acid chain length to regulate and reduce the fluidity and permeability of the cell membranes [19,66,67].…”

Transcriptomic responses associated with carbon and energy flows under high salinity stress suggest the overflow of acetyl-CoA from glycolysis and NADPH co-factor induces high lipid accumulation and halotolerance inChlorellasp. HS2

“…Importantly, the upregulation of P-type Cu + transporter (RAN1) on MAPK signaling pathway was observed in HS2 – the activity of RAN1 was determined to be positively correlated with plant cold resistance and the overexpression of RAN1 was further reported to increase abiotic stress tolerance in Arabidopsis thaliana (Xu & Cai, 2014; Xu, Zang, Chen, & Cai, 2016; Yang et al, 2018). Furthermore, the increased relative proportion of saturated and mono-saturated fatty acids in HS2 under high salinity stress following the upregulation of enzymes involved in the synthesis of palmitoleate (C16:1), stearate (C18:0), and oleate (C18:1n9c) (Guo, Liu, & Barkla, 2019). Hence, the putative remediation of oxidative stress under growth-inhibiting high salinity condition seems to concurrently involve signal transduction and a shift in membrane fluidity (Guo et al, 2019), in addition to directing excess precursor and co-factor towards lipid synthesis.…”

“…Furthermore, the increased relative proportion of saturated and mono-saturated fatty acids in HS2 under high salinity stress following the upregulation of enzymes involved in the synthesis of palmitoleate (C16:1), stearate (C18:0), and oleate (C18:1n9c) (Guo, Liu, & Barkla, 2019). Hence, the putative remediation of oxidative stress under growth-inhibiting high salinity condition seems to concurrently involve signal transduction and a shift in membrane fluidity (Guo et al, 2019), in addition to directing excess precursor and co-factor towards lipid synthesis.…”

Detergent Resistant Membrane Domains in Broccoli Plasma Membrane Associated to the Response to Salinity Stress

“…PM is important in the response and defence of plants against salinity because it is one of the cell parts that salt reaches first. Membrane lipids and transport proteins have an important function in regulating the permeability of PM, which triggers responses to salinity [ 3 ]. Since the control of water and nutrient distribution in the whole plant is an important factor in the acclimation of plants to a saline environment, the role of membrane proteins, such as aquaporins, is crucial, which has been widely reported in different species, such as Arabidopsis [ 4 ], maize [ 5 ] and broccoli [ 6 ].…”