The Salt Tolerance Related Protein (STRP) Mediates Cold Stress Responses and Abscisic Acid Signalling in Arabidopsis thaliana

Abstract Background Sucrose nonfermenting-1 (SNF1)-related protein kinases (SnRKs) play important roles in regulating metabolism and stress responses in plants, providing a conduit for crosstalk between metabolic and stress signalling, in some cases involving the stress hormone, abscisic acid (ABA). The burgeoning and divergence of the plant gene family has led to the evolution of three subfamilies, SnRK1, SnRK2 and SnRK3, of which SnRK2 and SnRK3 are unique to plants. Therefore, the study of SnRKs in crops may lead to the development of strategies for breeding crop varieties that are more resilient under stress conditions. In the present study, we describe the SnRK gene family of barley (Hordeum vulgare), the widespread cultivation of which can be attributed to its good adaptation to different environments. Results The barley HvSnRK gene family was elucidated in its entirety from publicly-available genome data and found to comprise 50 genes. Phylogenetic analyses assigned six of the genes to the HvSnRK1 subfamily, 10 to HvSnRK2 and 34 to HvSnRK3. The search was validated by applying it to Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa) genome data, identifying 50 SnRK genes in rice (four OsSnRK1, 11 OsSnRK2 and 35 OsSnRK3) and 39 in Arabidopsis (three AtSnRK1, 10 AtSnRK2 and 26 AtSnRK3). Specific motifs were identified in the encoded barley proteins, and multiple putative regulatory elements were found in the gene promoters, with light-regulated elements (LRE), ABA response elements (ABRE) and methyl jasmonate response elements (MeJa) the most common. RNA-seq analysis showed that many of the HvSnRK genes responded to ABA, some positively, some negatively and some with complex time-dependent responses. Conclusions The barley HvSnRK gene family is large, comprising 50 members, subdivided into HvSnRK1 (6 members), HvSnRK2 (10 members) and HvSnRK3 (34 members), showing differential positive and negative responses to ABA.

Download Full-text

Overexpression of SgGH3.1 from Fine-Stem Stylo (Stylosanthes guianensis var. intermedia) Enhances Chilling and Cold Tolerance in Arabidopsis thaliana

Genes ◽

10.3390/genes12091367 ◽

2021 ◽

Vol 12 (9) ◽

pp. 1367

Author(s):

Ming Jiang ◽

Long-Long Ma ◽

Huai-An Huang ◽

Shan-Wen Ke ◽

Chun-Sheng Gui ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Cold Stress ◽

Stress Responses ◽

Molecular Mechanisms ◽

Transcriptome Profiling ◽

Pasture Legumes ◽

Cold Tolerant ◽

Whole Transcriptome ◽

Altered Sensitivity ◽

Exogenous Iaa

Stylosanthes (stylo) species are commercially significant tropical and subtropical forage and pasture legumes that are vulnerable to chilling and frost. However, little is known about the molecular mechanisms behind stylos’ responses to low temperature stress. Gretchen-Hagen 3 (GH3) proteins have been extensively investigated in many plant species for their roles in auxin homeostasis and abiotic stress responses, but none have been reported in stylos. SgGH3.1, a cold-responsive gene identified in a whole transcriptome profiling study of fine-stem stylo (S. guianensis var. intermedia) was further investigated for its involvement in cold stress tolerance. SgGH3.1 shared a high percentage of identity with 14 leguminous GH3 proteins, ranging from 79% to 93%. Phylogenetic analysis classified SgGH3.1 into Group Ⅱ of GH3 family, which have been proven to involve with auxins conjugation. Expression profiling revealed that SgGH3.1 responded rapidly to cold stress in stylo leaves. Overexpression of SgGH3.1 in Arabidopsis thaliana altered sensitivity to exogenous IAA, up-regulated transcription of AtCBF1-3 genes, activated physiological responses against cold stress, and enhanced chilling and cold tolerances. This is the first report of a GH3 gene in stylos, which not only validated its function in IAA homeostasis and cold responses, but also gave insight into breeding of cold-tolerant stylos.

Download Full-text

Balancing salinity stress responses in halophytes and non-halophytes: a comparison between Thellungiella and Arabidopsis thaliana

Functional Plant Biology ◽

10.1071/fp12299 ◽

2013 ◽

Vol 40 (9) ◽

pp. 819 ◽

Cited By ~ 27

Author(s):

Dorothea Bartels ◽

Challabathula Dinakar

Keyword(s):

Arabidopsis Thaliana ◽

Salt Tolerance ◽

Salinity Tolerance ◽

Stress Responses ◽

Molecular Mechanisms ◽

Light Stress ◽

Stress Factors ◽

Natural Environments ◽

Terrestrial Plants ◽

Abiotic Stress Factors

Salinity is one of the major abiotic stress factors that drastically reduces agricultural productivity. In natural environments salinity often occurs together with other stresses such as dehydration, light stress or high temperature. Plants cope with ionic stress, dehydration and osmotic stress caused by high salinity through a variety of mechanisms at different levels involving physiological, biochemical and molecular processes. Halophytic plants exist successfully in stressful saline environments, but most of the terrestrial plants including all crop plants are glycophytes with varying levels of salt tolerance. An array of physiological, structural and biochemical adaptations in halophytes make them suitable models to study the molecular mechanisms associated with salinity tolerance. Comparative analysis of plants that differ in their abilities to tolerate salinity will aid in better understanding the phenomenon of salinity tolerance. The halophyte Thellungiella salsuginea has been used as a model for studying plant salt tolerance. In this review, T. salsuginea and the glycophyte Arabidopsis thaliana are compared with regards to their biochemical, physiological and molecular responses to salinity. In addition recent developments are presented for improvement of salinity tolerance in glycophytic plants using genes from halophytes.

Download Full-text

CKB1 is involved in abscisic acid and gibberellic acid signaling to regulate stress responses in Arabidopsis thaliana

Journal of Plant Research ◽

10.1007/s10265-017-0924-6 ◽

2017 ◽

Vol 130 (3) ◽

pp. 587-598 ◽

Cited By ~ 11

Author(s):

Congying Yuan ◽

Jianping Ai ◽

Hongping Chang ◽

Wenjun Xiao ◽

Lu Liu ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Abscisic Acid ◽

Gibberellic Acid ◽

Stress Responses ◽

Gibberellic Acid Signaling

Download Full-text

CRK2 enhances salt tolerance in Arabidopsis thaliana by regulating endocytosis and callose deposition in connection with PLDα1

10.1101/487009 ◽

2018 ◽

Cited By ~ 1

Author(s):

Kerri Hunter ◽

Sachie Kimura ◽

Anne Rokka ◽

Cuong Tran ◽

Masatsugu Toyota ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Salt Stress ◽

Salt Tolerance ◽

Subcellular Localization ◽

Stress Responses ◽

Negative Regulator ◽

Biotic And Abiotic Stress ◽

Callose Deposition ◽

Receptor Like Kinase ◽

Stress Dependent

AbstractHigh salinity has become an increasingly prevalent source of stress to which plants need to adapt. The receptor-like protein kinases (RLKs), including the cysteine-rich receptor-like kinase (CRK) subfamily, are a highly expanded family of transmembrane proteins in plants and are largely responsible for communication between cells and the extracellular environment. Various CRKs have been implicated in biotic and abiotic stress responses, however their functions on a cellular level remain largely uncharacterized. Here we have shown that CRK2 enhances salt tolerance at the germination stage in Arabidopsis thaliana. We identified CRK2 as a negative regulator of endocytosis, under both normal growth conditions and salt stress. We also established that functional CRK2 is required for salt-induced callose deposition. In doing so, we revealed a novel role for callose deposition, in response to increased salinity, and demonstrated its importance for salt tolerance during germination. Using fluorescently tagged proteins we observed specific changes in CRK2’s subcellular localization in response to various stress treatments. Many of CRK2’s cellular functions were dependent on phospholipase D (PLD) activity, as were the subcellular localization changes. Thus we propose that CRK2 acts downstream of PLD during salt stress to regulate endocytosis and promote callose deposition, and that CRK2 adopts specific stress-dependent subcellular localization patterns in order to carry out its functions.One sentence summaryThe receptor-like kinase CRK2 acts in connection with PLDα1 to regulate endocytosis and callose deposition at plasmodesmata, enhancing salt tolerance in Arabidopsis thaliana.

Download Full-text

Importin-β From the Recretohalophyte Limonium bicolor Enhances Salt Tolerance in Arabidopsis thaliana by Reducing Root Hair Development and Abscisic Acid Sensitivity

Frontiers in Plant Science ◽

10.3389/fpls.2020.582459 ◽

2021 ◽

Vol 11 ◽

Author(s):

Yanyu Xu ◽

Xiangmei Jiao ◽

Xi Wang ◽

Haonan Zhang ◽

Baoshan Wang ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Abscisic Acid ◽

Salt Tolerance ◽

Root Hair ◽

Salt Gland ◽

Physiological Parameters ◽

Limonium Bicolor ◽

Root Hair Development ◽

Aba Sensitivity ◽

Hair Development

AimsTo elucidate the genetics underlying salt tolerance in recretohalophytes and assess its relevance to non-halophytes, we cloned the Limonium bicolor homolog of Arabidopsis thaliana (Arabidopsis) SUPER SENSITIVE TO ABA AND DROUGHT2 (AtSAD2) and named it LbSAD2, an importin-β gene associated with trichome initiation and reduced abscisic acid (ABA) sensitivity, and then we assessed the heterologously expressed LbSAD2 in Arabidopsis.MethodsWe examined LbSAD2 expression and assessed the effect of heterologous LbSAD2 expression in Arabidopsis on root hair/trichome induction; the expression levels of possible related genes in trichome/root hair development; some physiological parameters involved in salt tolerance including germination rate, root length, and contents of Na+, proline, and malondialdehyde; and the response of ABA at the germination stage.ResultsThe LbSAD2 gene is highly expressed in the salt gland development stage and salt treatment, especially located in the salt gland by in situ hybridization, and the LbSAD2 protein contains some special domains compared with AtSAD2, which may suggest the involvement of LbSAD2 in salt tolerance. Compared with the SAD2/GL1 mutant CS65878, which lacks trichomes, CS65878-35S:LbSAD2 had higher trichome abundance but lower root hair abundance. Under 100 mM NaCl treatment, CS65878-35S:LbSAD2 showed enhanced germination and root lengths; improved physiological parameters, including high proline and low contents of Na+ and malondialdehyde; higher expression of the salt-tolerance genes Δ1-PYRROLINE-5-CARBOXYLATE SYNTHETASE 1 (P5CS1) and GST CLASS TAU 5 (GSTU5); reduced ABA sensitivity; and increased expression of the ABA signaling genes RESPONSIVE TO ABA 18 (RAB18) and SNF1-RELATED PROTEIN KINASE 2 (SRK2E), but not of the ABA biosynthesis gene 9-CIS-EPOXYCAROTENOID DIOXYGENASE 3 (NCED3).ConclusionLbSAD2 enhances salt tolerance in Arabidopsis by specifically reducing root hair development, Na+ accumulation, and ABA sensitivity.

Download Full-text

Abscisic Acid, Stress, and Ripening (TtASR1) Gene as a Functional Marker for Salt Tolerance in Durum Wheat

BioMed Research International ◽

10.1155/2020/7876357 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Karama Hamdi ◽

Faiçal Brini ◽

Najla Kharrat ◽

Khaled Masmoudi ◽

Inès Yakoubi

Keyword(s):

Abscisic Acid ◽

Salt Tolerance ◽

Durum Wheat ◽

Stress Responses ◽

Expression Patterns ◽

Acid Stress ◽

Wheat Breeding ◽

Functional Marker ◽

Environmental Signals ◽

Heat And Cold Stress

In semiarid Mediterranean agroecosystems, drought and salinity are the main abiotic stresses hampering wheat productivity and yield instability. Abscisic acid, stress, and ripening (ASR) are small plant proteins and play important roles in different biological processes. In the present study, the TtASR1 gene was isolated and characterized for the first time from durum wheat (Tritucum turgidum L. subsp. durum). TtASR1 is a small gene, about 684 bp long, located on chromosome 4AL, encoding a protein of 136 amino acid residues consisting of a histidine-rich N terminus and C-terminal conserved ABA-WDS domain (Pfam PF02496). Our results showed that TtASR1 protein could function as a chaperone-like protein and improve the viability of E. coli under heat and cold stress and increase the Saccharomyces cerevisiae tolerance under salt and osmotic stress. Transcript expression patterns of TtASR1 revealed that ASRs play important roles in abiotic stress responses in diverse organs. Indeed, TtASR1 was upregulated in leaves by different developmental (ABA) and environmental signals (PEG, salt). In cv. Mahmoudi (salt-tolerant Tunisian durum landraces) roots, TtASR1 was upregulated by salt stress, while it was downregulated in cv. Azizi (salt-sensitive Tunisian durum landraces), supporting the implication of this gene in the salt tolerance mechanism. Taken together and after validation in the plant system, the TtASR1 gene may provide a potential functional marker for marker-assisted selection in a durum wheat breeding program for salt tolerance.

Download Full-text

Low Mannitol Concentrations in Arabidopsis thaliana Expressing Ectocarpus Genes Improve Salt Tolerance

Plants ◽

10.3390/plants9111508 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1508

Author(s):

Pramod Rathor ◽

Tudor Borza ◽

Yanhui Liu ◽

Yuan Qin ◽

Sophia Stone ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Salt Tolerance ◽

Transgenic Plants ◽

Salinity Stress ◽

Stress Responses ◽

Molecular Mechanisms ◽

Ion Homeostasis ◽

Biotic And Abiotic Stress ◽

Expression Of Genes ◽

Wide Range

Mannitol is abundant in a wide range of organisms, playing important roles in biotic and abiotic stress responses. Nonetheless, mannitol is not produced by a vast majority of plants, including many important crop plants. Mannitol-producing transgenic plants displayed improved tolerance to salt stresses though mannitol production was rather low, in the µM range, compared to mM range found in plants that innately produce mannitol. Little is known about the molecular mechanisms underlying salt tolerance triggered by low concentrations of mannitol. Reported here is the production of mannitol in Arabidopsis thaliana, by expressing two mannitol biosynthesis genes from the brown alga Ectocarpus sp. strain Ec32. To date, no brown algal genes have been successfully expressed in land plants. Expression of mannitol-1-phosphate dehydrogenase and mannitol-1-phosphatase genes was associated with the production of 42.3–52.7 nmol g−1 fresh weight of mannitol, which was sufficient to impart salinity and temperature stress tolerance. Transcriptomics revealed significant differences in the expression of numerous genes, in standard and salinity stress conditions, including genes involved in K+ homeostasis, ROS signaling, plant development, photosynthesis, ABA signaling and secondary metabolism. These results suggest that the improved tolerance to salinity stress observed in transgenic plants producing mannitol in µM range is achieved by the activation of a significant number of genes, many of which are involved in priming and modulating the expression of genes involved in a variety of functions including hormone signaling, osmotic and oxidative stress, and ion homeostasis.

Download Full-text

Mutations in ABO1/ELO2, a Subunit of Holo-Elongator, Increase Abscisic Acid Sensitivity and Drought Tolerance in Arabidopsis thaliana

Molecular and Cellular Biology ◽

10.1128/mcb.00433-06 ◽

2006 ◽

Vol 26 (18) ◽

pp. 6902-6912 ◽

Cited By ~ 101

Author(s):

Zhizhong Chen ◽

Hairong Zhang ◽

Daniel Jablonowski ◽

Xiaofeng Zhou ◽

Xiaozhi Ren ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Abscisic Acid ◽

Stress Responses ◽

Killer Toxin ◽

Acid Sensitivity ◽

Iκb Kinase ◽

Aba Sensitivity ◽

A Subunit ◽

Yeast Killer ◽

Yeast Killer Toxin

ABSTRACT The phytohormone abscisic acid (ABA) plays an important role in modulating plant growth, development, and stress responses. In a genetic screen for mutants with altered drought stress responses, we identified an ABA-overly sensitive mutant, the abo1 mutant, which showed a drought-resistant phenotype. The abo1 mutation enhances ABA-induced stomatal closing and increases ABA sensitivity in inhibiting seedling growth. abo1 mutants are more resistant to oxidative stress than the wild type and show reduced levels of transcripts of several stress- or ABA-responsive genes. Interestingly, the mutation also differentially modulates the development and growth of adjacent guard cells. Map-based cloning identified ABO1 as a new allele of ELO2, which encodes a homolog of Saccharomyces cerevisiae Iki3/Elp1/Tot1 and human IκB kinase-associated protein. Iki3/Elp1/Tot1 is the largest subunit of Elongator, a multifunctional complex with roles in transcription elongation, secretion, and tRNA modification. Ecotopic expression of plant ABO1/ELO2 in a tot1/elp1Δ yeast Elongator mutant complements resistance to zymocin, a yeast killer toxin complex, indicating that ABO1/ELO2 substitutes for the toxin-relevant function of yeast Elongator subunit Tot1/Elp1. Our results uncover crucial roles for ABO1/ELO2 in modulating ABA and drought responses in Arabidopsis thaliana.

Download Full-text

SNF1-related protein kinase 2 directly regulate group C Raf-like protein kinases in abscisic acid signaling

10.1101/2020.02.04.933978 ◽

2020 ◽

Cited By ~ 1

Author(s):

Yoshiaki Kamiyama ◽

Misaki Hirotani ◽

Shinnosuke Ishikawa ◽

Fuko Minegishi ◽

Sotaro Katagiri ◽

...

Keyword(s):

Abscisic Acid ◽

Protein Kinase ◽

Stress Responses ◽

Reverse Genetic ◽

Aba Signaling ◽

Related Protein ◽

Wild Type ◽

In Planta ◽

Interacting Protein ◽

Biochemical Analyses

ABSTRUCTA phytohormone abscisic acid (ABA) has a major role in abiotic stress responses in plants, and subclass III SNF1-related protein kinase 2 (SnRK2) mediates ABA signaling. In this study, we identified Raf36, a group C Raf-like protein kinase in Arabidopsis, as an interacting protein with SnRK2. A series of reverse genetic and biochemical analyses revealed that Raf36 negatively regulates ABA responses and is directly phosphorylated by SnRK2s. In addition, we found that Raf22, another C-type Raf-like kinase, functions partially redundantly with Raf36 to regulate ABA responses. Comparative phosphoproteomic analysis using Arabidopsis wild-type and raf22raf36-1 plants identified proteins that are phosphorylated downstream of Raf36 and Raf22 in planta. Together, these results reveal a novel subsection of ABA-responsive phosphosignaling pathways branching from SnRK2.

Download Full-text