Osmotic Stress Responses and Plant Growth Controlled by Potassium Transporters in Arabidopsis

Abstract Drought stress forms a major environmental constraint during the life cycle of plants, often decreasing plant yield and in extreme cases threatening survival. The molecular and physiological responses induced by drought have been the topic of extensive research during the past decades. Because soil-based approaches to studying drought responses are often challenging due to low throughput and insufficient control of the conditions, osmotic stress assays in plates were developed to mimic drought. Addition of compounds such as polyethylene glycol, mannitol, sorbitol, or NaCl to controlled growth media has become increasingly popular since it offers the advantage of accurate control of stress level and onset. These osmotic stress assays enabled the discovery of very early stress responses, occurring within seconds or minutes following osmotic stress exposure. In this review, we construct a detailed timeline of early responses to osmotic stress, with a focus on how they initiate plant growth arrest. We further discuss the specific responses triggered by different types and severities of osmotic stress. Finally, we compare short-term plant responses under osmotic stress versus in-soil drought and discuss the advantages, disadvantages, and future of these plate-based proxies for drought.

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Genome-Wide Identification, Characterization and Expression Analysis of the CIPK Gene Family in Potato (Solanum tuberosum L.) and the Role of StCIPK10 in Response to Drought and Osmotic Stress

International Journal of Molecular Sciences ◽

10.3390/ijms222413535 ◽

2021 ◽

Vol 22 (24) ◽

pp. 13535

Author(s):

Rui Ma ◽

Weigang Liu ◽

Shigui Li ◽

Xi Zhu ◽

Jiangwei Yang ◽

...

Keyword(s):

Abiotic Stress ◽

Solanum Tuberosum ◽

Plant Growth ◽

Osmotic Stress ◽

Stress Responses ◽

Solanum Tuberosum L ◽

Abiotic Stress Tolerance ◽

Stomatal Closure ◽

Interacting Protein ◽

Reverse Transcription Pcr

The potato (Solanum tuberosum L.), one of the most important food crops worldwide, is sensitive to environmental stresses. Sensor–responder complexes comprising calcineurin B-like (CBL) proteins and CBL-interacting protein kinases (CIPKs) not only modulate plant growth and development but also mediate numerous stress responses. Here, using a Hidden Markov Model and BLAST searches, 27 CIPK genes were identified in potato and divided into five groups by phylogenetic analysis and into two clades (intron-poor and intron-rich) by gene structure analysis. Quantitative reverse-transcription PCR (qRT-PCR) assays revealed that StCIPK genes play important roles in plant growth, development and abiotic stress tolerance. Up-regulated expression of StCIPK10 was significantly induced by drought, PEG6000 and ABA. StCIPK10 enhances both the ability of potato to scavenge reactive oxygen species and the content of corresponding osmoregulation substances, thereby strengthening tolerance to drought and osmotic stress. StCIPK10 is located at the intersection between the abscisic acid and abiotic stress signaling pathways, which control both root growth and stomatal closure in potato. In addition, StCIPK10 interacts with StCBL1, StCBL4, StCBL6, StCBL7, StCBL8, StCBL11 and StCBL12, and is specifically recruited to the plasma membrane by StCBL11.

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Down Regulation and Loss of Auxin Response Factor 4 Function Using CRISPR/Cas9 Alters Plant Growth, Stomatal Function and Improves Tomato Tolerance to Salinity and Osmotic Stress

Genes ◽

10.3390/genes11030272 ◽

2020 ◽

Vol 11 (3) ◽

pp. 272 ◽

Cited By ~ 6

Author(s):

Sarah Bouzroud ◽

Karla Gasparini ◽

Guojian Hu ◽

Maria Antonia Machado Barbosa ◽

Bruno Luan Rosa ◽

...

Keyword(s):

Plant Growth ◽

Osmotic Stress ◽

Stress Responses ◽

Target Genes ◽

Soluble Sugars ◽

Auxin Response ◽

Down Regulation ◽

Aba Content ◽

Tolerance To Salinity ◽

Salt And Osmotic Stress

Auxin controls multiple aspects of plant growth and development. However, its role in stress responses remains poorly understood. Auxin acts on the transcriptional regulation of target genes, mainly through Auxin Response Factors (ARF). This study focuses on the involvement of SlARF4 in tomato tolerance to salinity and osmotic stress. Using a reverse genetic approach, we found that the antisense down-regulation of SlARF4 promotes root development and density, increases soluble sugars content and maintains chlorophyll content at high levels under stress conditions. Furthermore, ARF4-as displayed higher tolerance to salt and osmotic stress through reduced stomatal conductance coupled with increased leaf relative water content and Abscisic acid (ABA) content under normal and stressful conditions. This increase in ABA content was correlated with the activation of ABA biosynthesis genes and the repression of ABA catabolism genes. Cu/ZnSOD and mdhar genes were up-regulated in ARF4-as plants which can result in a better tolerance to salt and osmotic stress. A CRISPR/Cas9 induced SlARF4 mutant showed similar growth and stomatal responses as ARF4-as plants, which suggest that arf4-cr can tolerate salt and osmotic stresses. Our data support the involvement of ARF4 as a key factor in tomato tolerance to salt and osmotic stresses and confirm the use of CRISPR technology as an efficient tool for functional reverse genetics studies.

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Loss of AUXIN RESPONSE FACTOR 4 function alters plant growth, stomatal function and improves tomato tolerance to salinity and osmotic stress

10.1101/756387 ◽

2019 ◽

Author(s):

Sarah Bouzroud ◽

Karla Gasparini ◽

Guojian Hu ◽

Maria Antonia Machado Barbosa ◽

Bruno Luan Rosa ◽

...

Keyword(s):

Plant Growth ◽

Osmotic Stress ◽

Stress Responses ◽

Target Genes ◽

Soluble Sugars ◽

Auxin Response ◽

Response Factors ◽

Aba Content ◽

Tolerance To Salinity ◽

Salt And Osmotic Stress

AbstractAuxin controls multiple aspects of plant growth and development. However, its role in stress responses remains poorly understood. Auxin acts on the transcriptional regulation of target genes, mainly through Auxin Response Factors (ARF). This study focuses on the involvement of SlARF4 in tomato tolerance to salinity and osmotic stress. Using a reverse genetic approach, we found that the antisense down-regulation of SlARF4 promotes root development and density, increases soluble sugars content and maintains chlorophyll content at high levels under stress conditions. Furthermore, ARF4-as displayed higher tolerance to salt and osmotic stress through reduced stomatal conductance coupled with increased leaf relative water content and ABA content under normal and stressful conditions. This increase in ABA content was correlated with the activation of ABA biosynthesis genes and the repression of ABA catabolism genes. cat1, Cu/ZnSOD and mdhar genes were up-regulated in ARF4-as plants which can result in a better tolerance to salt and osmotic stress. A CRISPR/Cas9 induced SlARF4 mutant showed similar growth and stomatal responses as ARF4-as plants, which suggest that arf4-cr can tolerate salt and osmotic stresses. Our data support the involvement of ARF4 as a key factor in tomato tolerance to salt and osmotic stresses and confirm the use of CRISPR technology as an efficient tool for functional reverse genetics studies.

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Silicon Stimulates Plant Growth and Metabolism in Rice Plants under Conventional and Osmotic Stress Conditions

Plants ◽

10.3390/plants10040777 ◽

2021 ◽

Vol 10 (4) ◽

pp. 777

Author(s):

Sara Monzerrat Ramírez-Olvera ◽

Libia Iris Trejo-Téllez ◽

Fernando Carlos Gómez-Merino ◽

Lucero del Mar Ruíz-Posadas ◽

Ernesto Gabriel Alcántar-González ◽

...

Keyword(s):

Plant Growth ◽

Osmotic Stress ◽

Abiotic Factors ◽

Stress Conditions ◽

Chlorophyll B ◽

Rice Seedlings ◽

Root Volume ◽

Total Sugars ◽

Dry Biomass ◽

Peg 8000

Exogenous silicon (Si) can enhance plant resistance to various abiotic factors causing osmotic stress. The objective of this research was to evaluate the application of 1 and 2 mM Si to plants under normal conditions and under osmotic stress. Morelos A-98 rice seedlings, were treated with 1 and 2 mM SiO2 for 28 d. Subsequently, half of the plants were subjected to osmotic stress with the addition of 10% polyethylene glycol (PEG) 8000; and continued with the addition of Si (0, 1 and 2 mM SiO2) for both conditions. The application of Si under both conditions increased chlorophyll b in leaves, root volume, as well as fresh and dry biomass of roots. Interestingly, the number of tillers, shoot fresh and dry biomass, shoot water content, concentration of total chlorophyll, chlorophyll a/b ratio, and the concentration of total sugars and proline in shoot increased with the addition of Si under osmotic stress conditions. The addition of Si under normal conditions decreased the concentration of sugars in the roots, K and Mn in roots, and increased the concentration of Fe and Zn in shoots. Therefore, Si can be used as a potent inorganic biostimulant in rice Morelos A-98 since it stimulates plant growth and modulates the concentration of vital biomolecules and essential nutrients.

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Growth Promotion or Osmotic Stress Response: How SNF1-Related Protein Kinase 2 (SnRK2) Kinases Are Activated and Manage Intracellular Signaling in Plants

Plants ◽

10.3390/plants10071443 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1443

Author(s):

Yoshiaki Kamiyama ◽

Sotaro Katagiri ◽

Taishi Umezawa

Keyword(s):

Protein Kinase ◽

Plant Growth ◽

Osmotic Stress ◽

Protein Function ◽

Intracellular Signaling ◽

Growth Promotion ◽

Research Field ◽

Dependent Manner ◽

Related Protein ◽

Wide Range

Reversible phosphorylation is a major mechanism for regulating protein function and controls a wide range of cellular functions including responses to external stimuli. The plant-specific SNF1-related protein kinase 2s (SnRK2s) function as central regulators of plant growth and development, as well as tolerance to multiple abiotic stresses. Although the activity of SnRK2s is tightly regulated in a phytohormone abscisic acid (ABA)-dependent manner, recent investigations have revealed that SnRK2s can be activated by group B Raf-like protein kinases independently of ABA. Furthermore, evidence is accumulating that SnRK2s modulate plant growth through regulation of target of rapamycin (TOR) signaling. Here, we summarize recent advances in knowledge of how SnRK2s mediate plant growth and osmotic stress signaling and discuss future challenges in this research field.

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Osmotic Stress or Ionic Composition: Which Affects the Early Growth of Crop Species More?

Agronomy ◽

10.3390/agronomy11030435 ◽

2021 ◽

Vol 11 (3) ◽

pp. 435

Author(s):

Agnieszka Ludwiczak ◽

Monika Osiak ◽

Stefany Cárdenas-Pérez ◽

Sandra Lubińska-Mielińska ◽

Agnieszka Piernik

Keyword(s):

Osmotic Stress ◽

Stress Responses ◽

Ionic Composition ◽

Degradation Process ◽

Early Growth ◽

Cultivated Plants ◽

C3 Plants ◽

Growth Stages ◽

Crop Species ◽

Ionic Salt

Salinization is a key soil degradation process. An estimated 20% of total cultivated lands and 33% of irrigated agricultural lands worldwide are affected by high salinity. Much research has investigated the influence of salt (mainly NaCl) on plants, but very little is known about how this is related to natural salinity and osmotic stress. Therefore, our study was conducted to determine the osmotic and ionic salt stress responses of selected C3 and C4 cultivated plants. We focused on the early growth stages as those critical for plant development. We applied natural brine to simulate natural salinity and to compare its effect to NaCl solution. We assessed traits related to germination ability, seedlings and plantlet morphology, growth indexes, and biomass and water accumulation. Our results demonstrate that the effects of salinity on growth are strongest among plantlets. Salinity most affected water absorption in C3 plants (28% of total traits variation), but plant length in C4 plants (17–27%). Compensatory effect of ions from brine were suggested by the higher model plants’ growth success of ca 5–7% under brine compared to the NaCl condition. However, trait differences indicated that osmotic stress was the main stress factor affecting the studied plants.

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