Seasonal Relations between the Content of Amino Acids and Freezing Tolerance of Leaves of Halimione portulacoides under Different Salt Stress

Watermelon (Citrullus lanatus L.) is a widely popular vegetable fruit crop for human consumption. Soil salinity is among the most critical problems for agricultural production, food security, and sustainability. The transcriptomic and the primary molecular mechanisms that underlie the salt-induced responses in watermelon plants remain uncertain. In this study, the photosynthetic efficiency of photosystem II, free amino acids, and transcriptome profiles of watermelon seedlings exposed to short-term salt stress (300 mM NaCl) were analyzed to identify the genes and pathways associated with response to salt stress. We observed that the maximal photochemical efficiency of photosystem II decreased in salt-stressed plants. Most free amino acids in the leaves of salt-stressed plants increased many folds, while the percent distribution of glutamate and glutamine relative to the amino acid pool decreased. Transcriptome analysis revealed 7622 differentially expressed genes (DEGs) under salt stress, of which 4055 were up-regulated. The GO analysis showed that the molecular function term “transcription factor (TF) activity” was enriched. The assembled transcriptome demonstrated up-regulation of 240 and down-regulation of 194 differentially expressed TFs, of which the members of ERF, WRKY, NAC bHLH, and MYB-related families were over-represented. The functional significance of DEGs associated with endocytosis, amino acid metabolism, nitrogen metabolism, photosynthesis, and hormonal pathways in response to salt stress are discussed. The findings from this study provide novel insights into the salt tolerance mechanism in watermelon.

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Physiological and Biochemical Responses to Salt Stress of Alfalfa Populations Selected for Salinity Tolerance and Grown in Symbiosis with Salt-Tolerant Rhizobium

Agronomy ◽

10.3390/agronomy10040569 ◽

2020 ◽

Vol 10 (4) ◽

pp. 569

Author(s):

Annick Bertrand ◽

Craig Gatzke ◽

Marie Bipfubusa ◽

Vicky Lévesque ◽

Francois P. Chalifour ◽

...

Keyword(s):

Amino Acids ◽

Salt Stress ◽

Salt Tolerance ◽

Water Content ◽

Salinity Tolerance ◽

Osmotic Adjustment ◽

Recurrent Selection ◽

Aromatic Amino Acids ◽

Nacl Stress ◽

Salt Tolerant

Alfalfa and its rhizobial symbiont are sensitive to salinity. We compared the physiological responses of alfalfa populations inoculated with a salt-tolerant rhizobium strain, exposed to five NaCl concentrations (0, 20, 40, 80, or 160 mM NaCl). Two initial cultivars, Halo (H-TS0) and Bridgeview (B-TS0), and two populations obtained after three cycles of recurrent selection for salt tolerance (H-TS3 and B-TS3) were compared. Biomass, relative water content, carbohydrates, and amino acids concentrations in leaves and nodules were measured. The higher yield of TS3-populations than initial cultivars under salt stress showed the effectiveness of our selection method to improve salinity tolerance. Higher relative root water content in TS3 populations suggests that root osmotic adjustment is one of the mechanisms of salt tolerance. Higher concentrations of sucrose, pinitol, and amino acid in leaves and nodules under salt stress contributed to the osmotic adjustment in alfalfa. Cultivars differed in their response to recurrent selection: under a 160 mM NaCl-stress, aromatic amino acids and branched-chain amino acids (BCAAs) increased in nodules of B-ST3 as compared with B-TS0, while these accumulations were not observed in H-TS3. BCAAs are known to control bacteroid development and their accumulation under severe stress could have contributed to the high nodulation of B-TS3.

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Effects of salt stress on ion balance and nitrogen metabolism in rice

Plant Soil and Environment ◽

10.17221/615/2011-pse ◽

2012 ◽

Vol 58 (No. 2) ◽

pp. 62-67 ◽

Cited By ~ 9

Author(s):

H. Wang ◽

Z. Wu ◽

Y. Zhou ◽

J. Han ◽

D. Shi

Keyword(s):

Amino Acids ◽

Salt Stress ◽

Nitrogen Metabolism ◽

Inorganic Ions ◽

Subsequent Reduction ◽

Ion Balance ◽

Rice Plants ◽

Leaves And Roots ◽

Total Amino Acids ◽

Time Point

The aim of this study was to test the effects of salt stress on nitrogen metabolism and ion balance in rice plants. The contents of inorganic ions, total amino acids, and NO3– in the stressed seedlings were then measured. The expressions of some critical genes involved in nitrogen metabolism were also assayed to test their roles in the regulation of nitrogen metabolism during adaptation of rice to salt stress. The results showed that when seedlings were subjected to salt stress for 4 h, in roots, salt stress strongly stimulated the accumulations of Na+ and Cl–, and reduced K+ content; however, in leaves, only at 5 days these changes were observed. This confirmed that the response of root to salt stress was more sensitive than that of leaf. When seedlings were subjected to salt stress for 4 h, salt stress strongly stimulated the expression of OsGS1;1, OsNADH-GOGAT, OsAS, OsGS1;3, OsGDH1, OsGDH2, OsGDH3 in both leaves and roots of rice, after this time point their expression decreased. Namely, at 5 days most of genes involved in NH4+ assimilation were downregulated by salt stress, which might be the response to NO3– change. Salt stress did not reduce NO3– contents in both roots and leaves at 4 h, whereas at 5 days salt stress mightily decreased the NO3– contents. The deficiencies of NO3– in both roots and leaves can cause a large downregulation of OsNR1 and the subsequent reduction of NH4+ production. This event might immediately induce the downregulations of the genes involved in NH4+ assimilation.

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Free amino acids and glycine betaine in leaf osmoregulation of spinach responding to increasing salt stress

New Phytologist ◽

10.1046/j.1469-8137.2003.00770.x ◽

2003 ◽

Vol 158 (3) ◽

pp. 455-463 ◽

Cited By ~ 141

Author(s):

Catello Di Martino ◽

Sebastiano Delfine ◽

Roberto Pizzuto ◽

Francesco Loreto ◽

Amodio Fuggi

Keyword(s):

Amino Acids ◽

Salt Stress ◽

Glycine Betaine ◽

Free Amino Acids ◽

Free Amino

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Concentrations and Compositions of Internal Free Amino Acids in a HalotolerantBrevibacteriumsp. in Response to Salt Stress

Bioscience Biotechnology and Biochemistry ◽

10.1271/bbb.58.1873 ◽

1994 ◽

Vol 58 (10) ◽

pp. 1873-1874 ◽

Cited By ~ 10

Author(s):

Haruo Mimura ◽

Shinichi Nagata ◽

Tadashi Matsumoto

Keyword(s):

Amino Acids ◽

Salt Stress ◽

Free Amino Acids ◽

Free Amino

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Changes in Free Amino Acids and Stress Protein Synthesis in Two Genotypes of Green Gram under Salt Stress

Journal of Plant Sciences ◽

10.3923/jps.2006.56.66 ◽

2005 ◽

Vol 1 (1) ◽

pp. 56-66 ◽

Cited By ~ 12

Author(s):

Neelam Misra . ◽

Ajay Kumar Gupta . ◽

U.N. Dwivedi .

Keyword(s):

Amino Acids ◽

Protein Synthesis ◽

Salt Stress ◽

Free Amino Acids ◽

Free Amino ◽

Stress Protein ◽

Green Gram

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Saline Growth Conditions Favour Supercooling and Increase the Freezing Tolerance of Leaves of Barley and Wheat

Zeitschrift für Naturforschung C ◽

10.1515/znc-1992-9-1010 ◽

1992 ◽

Vol 47 (9-10) ◽

pp. 695-700 ◽

Cited By ~ 5

Author(s):

Michael Bender ◽

Ulrich Heber ◽

Karl-Josef Dietz

Keyword(s):

Salt Stress ◽

Freezing Tolerance ◽

Growth Conditions ◽

Ice Nucleation ◽

Ice Formation ◽

Freezing And Thawing ◽

Subzero Temperatures ◽

Cellular Dehydration ◽

Detached Leaves ◽

Leaf Survival

When young plants of barley and wheat grown in hydroponic culture were subjected to salt stress, their freezing tolerance increased with increasing severity of salt stress. Detached leaves from salt-stressed plants also exhibited an increased ability to supercool. Avoidance of ice formation permitted leaf survival at subzero temperatures which were no longer tolerated when ice nucleation resulted in extracellular freezing. The increased freezing tolerance under salt stress is attributed to osmotic adjustment of the plants. Increased cellular solute concentrations decrease the extent of cellular dehydration at freezing temperatures, thereby decreasing mechanical and chemical stresses on biomembranes during freezing and thawing.

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Short-Term Effects of Salt Stress on the Amino Acids of Phragmites australis Root Exudates in Constructed Wetlands

Water ◽

10.3390/w12020569 ◽

2020 ◽

Vol 12 (2) ◽

pp. 569 ◽

Cited By ~ 2

Author(s):

En Xie ◽

Xuejing Wei ◽

Aizhong Ding ◽

Lei Zheng ◽

Xiaona Wu ◽

...

Keyword(s):

Amino Acids ◽

Salt Stress ◽

Amino Acid ◽

Phragmites Australis ◽

Root Exudates ◽

Amino Acid Content ◽

Total Amino Acid ◽

Control Group ◽

Short Term ◽

Short Term Effects

In this study, the short-term effects of NaCl stress on the free amino acid content and composition of root exudates of Phragmites australis were evaluated. Nineteen amino acid types were detected in all samples. The results indicated that NaCl significantly influenced the total amino acid (TotAA) content. The TotAA content at 6‰ salinity (1098.79 μM g−1 DW) was up to 24 times higher than that in the control group (45.97 μM g−1 DW) but decreased to 106.32 μM g−1 DW at 6‰ salinity in the first hour. The stress period also significantly affected the TotAA content. After 4 h of stress, the TotAA content of the control and 1‰ salinity groups increased by approximately 30- and 14-fold, and those of the 3‰ and 6‰ groups decreased to 60% and 37%, respectively. The increase in TotAA content was primarily caused by the increase in proline content; the proportion of proline accounted for 58.05% of the TotAA content at 3‰ salinity level in 2 h. Most amino acids showed a significant positive correlation with each other, but proline and methionine showed a different trend. Therefore, the proline level is a useful indicator of salt stress in Phragmites australis, especially in saltwater wetlands.

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The Phylogenetic Analysis and Identification of a Novel Remorin Member from Rice(Oryza sativa L) by Proteomics under Salt Stress

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1073-1076.229 ◽

2014 ◽

Vol 1073-1076 ◽

pp. 229-232

Author(s):

Yan Wei Cheng ◽

Ai Qing Feng ◽

Zhen Bo Zhang ◽

Yan Zhao Zhang ◽

Jian Ming Han

Keyword(s):

Amino Acids ◽

Molecular Weight ◽

Phylogenetic Analysis ◽

Salt Stress ◽

Isoelectric Point ◽

Post Translational Modification ◽

Proteomics Research ◽

Root Proteomics ◽

Alignment Analysis ◽

Protein Molecular Weight

Rice root proteomics research identified to a new remorin1 protein,named OsREM1,which significantly increased (approximately 1.7-fold) compared with control under salt stress by Two-dimensional electrophoresis. It is found that the protein molecular weight is 29 kD, isoelectric point is 4.54. The bioinformatics analysis showed that: (1) The protein contains 195 amino acids, whose theoretical molecular weight is 21.3 kD, whose theoretical isoelectric point is 5.06. There are some differences with the experimental results, which may be the result of post-translational modification, such as glycosylation, phosphorylation; (2) The different crop remorin protein sequence alignment analysis found that the same rate of the amino acids is more than 50%, indicated that remorins are highly conserved protein; (3) Phylogenetic analysis showed OsREM1 had a low sequence identity with potao and tomato REM1, which is the agreement with traditional classification.

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Exogenous application of 24-epibrassinosteroid mitigates NaCl toxicity in flax by modifying free amino acids profile and antioxidant defence system

Functional Plant Biology ◽

10.1071/fp19191 ◽

2020 ◽

Vol 47 (6) ◽

pp. 565 ◽

Cited By ~ 1

Author(s):

Leila Amraee ◽

Fatemeh Rahmani ◽

Babak Abdollahi Mandoulakani

Keyword(s):

Amino Acids ◽

Antioxidant Enzymes ◽

Salt Stress ◽

Antioxidant Capacity ◽

Free Amino ◽

Ion Homeostasis ◽

Seed Priming ◽

Antioxidant Response ◽

Salinity Treatment ◽

Antioxidant Defence System

In the present study, we investigated the ameliorative effects of 24-epibrassinosteroid (24-epiBL) on antioxidant response and ion homeostasis in two NaCl-stressed Linum usitatissimum L. (flax) cultivars differing in salt tolerance. The content and profile of amino acids were also studied in the tolerant cultivar. Salt stress differently altered the activity of antioxidant enzymes, phenol and flavonoid contents, total antioxidant capacity and ion homeostasis in both cultivars, whereas H2O2 and malondialdehyde (MDA) contents were induced only in the TN-97-95 cultivar. Free amino acid concentrations showed variable patterns under salinity conditions compared with the control plants. 24-epiBL decreased the soluble protein content in NaCl-treated plants and also decreased stimulatory effects of salinity on the production and accumulation of phenol and flavonoid contents and antioxidant capacity with altered ion (Na+, K+, and Cl–) contents. The 24-epiBL reduced the chlorophylls (a, b) and carotenoid contents in salt-treated TN-97-95 cultivar while enhanced the activity of antioxidant enzymes and declined the H2O2 content and lipid peroxidation in both NaCl-stressed cultivars. The profile and content of amino acids were significantly changed by 24-epiBL application under salinity treatment. In summary, our findings demonstrate that 24-epiBL seed priming mitigates the deleterious effects of salt stress in flax plants.

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