scholarly journals Altered Root Growth, Auxin Metabolism and Distribution in Arabidopsis thaliana Exposed to Salt and Osmotic Stress

2021 ◽  
Vol 22 (15) ◽  
pp. 7993
Author(s):  
Ana Smolko ◽  
Nataša Bauer ◽  
Iva Pavlović ◽  
Aleš Pěnčík ◽  
Ondřej Novák ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Salt Stress ◽  
Osmotic Stress ◽  
Root Growth ◽  
Plant Root ◽  
Stress Factors ◽  
Quiescent Center ◽  
Gene Expressions ◽  
Auxin Distribution ◽  
Salt And Osmotic Stress

Salt and osmotic stress are the main abiotic stress factors affecting plant root growth and architecture. We investigated the effect of salt (100 mM NaCl) and osmotic (200 mM mannitol) stress on the auxin metabolome by UHPLC-MS/MS, auxin distribution by confocal microscopy, and transcript levels of selected genes by qRT-PCR in Arabidopsis thaliana ecotype Columbia-0 (Col-0) and DR5rev::GFP (DR5) line. During long-term stress (13 days), a stability of the auxin metabolome and a tendency to increase indole-3-acetic acid (IAA) were observed, especially during salt stress. Short-term stress (3 h) caused significant changes in the auxin metabolome, especially NaCl treatment resulted in a significant reduction of IAA. The data derived from auxin profiling were consistent with gene expressions showing the most striking changes in the transcripts of YUC, GH3, and UGT transcripts, suggesting disruption of auxin biosynthesis, but especially in the processes of amide and ester conjugation. These data were consistent with the auxin distribution observed in the DR5 line. Moreover, NaCl treatment caused a redistribution of auxin signals from the quiescent center and the inner layers of the root cap to the epidermal and cortical cells of the root elongation zone. The distribution of PIN proteins was also disrupted by salt stress; in particular, PIN2 was suppressed, even after 5 min of treatment. Based on our results, the DR5 line was more sensitive to the applied stresses than Col-0, although both lines showed similar trends in root morphology, as well as transcriptome and metabolome parameters under stress conditions.

scholarly journals AtSK11 and AtSK12 Mediate the Mild Osmotic Stress-Induced Root Growth Response in Arabidopsis

2020 ◽  
Vol 21 (11) ◽  
pp. 3991 ◽  
Author(s):  
Long Dong ◽  
Zhixin Wang ◽  
Jing Liu ◽  
Xuelu Wang
Keyword(s):  
Arabidopsis Thaliana ◽  
Transcription Factor ◽  
Plant Growth ◽  
Osmotic Stress ◽  
Root Growth ◽  
Growth Response ◽  
Glycogen Synthase ◽  
Plant Root ◽  
Bhlh Transcription Factor ◽  
Mild Stress

Although most osmotic stresses are harmful to plant growth and development, certain drought- or polyethylene glycol (PEG)-induced mild osmotic stresses promote plant root growth. The underlying regulatory mechanisms of this response remain elusive. Here, we report that the GLYCOGEN SYNTHASE KINASE 3 (GSK3) genes ARABIDOPSIS THALIANA SHAGGY-RELATED KINASE 11 (AtSK11) (AT5G26751) and AtSK12 (AT3G05840) are involved in the mild osmotic stress (−0.4 MPa) response in Arabidopsis thaliana. When grown on plant medium infused with different concentrations of PEG to mimic osmotic stress, both wild-type (WT) and atsk11atsk12 plants showed stimulated root growth under mild osmotic stress (−0.4 MPa) but repressed root growth under relatively strong osmotic stress (−0.5, −0.6, −0.7 MPa) as compared to the mock condition (−0.25 MPa). The root growth stimulation of atsk11atsk12 was more sensitive to −0.4 MPa treatment than was that of WT, indicating that AtSK11 and AtSK12 inhibit the mild stress-induced root growth response. RNA-seq analysis of WT and atsk11atsk12 plants under three water potentials (−0.25 MPa, −0.4 MPa, −0.6 MPa) revealed 10 differentially expressed candidate genes mainly involved in cell wall homeostasis, which were regulated by AtSK11 and AtSK12 to regulate root growth in response to the mild stress condition (−0.4 MPa). Promoter motif and transcription factor binding analyses suggested that the basic helix-loop-helix (bHLH) transcription factor bHLH69/LJRHL1-LIKE 2 (LRL2) may directly regulate the expression of most −0.4 MPa-responsive genes. These findings indicate that mild osmotic stress (−0.4 MPa) promotes plant growth and that the GSK3 family kinase genes AtSK11 and AtSK12 play a negative role in the induction of root growth in response to mild osmotic stress.

scholarly journals Overexpression of OsPIN2 Regulates Root Growth and Formation in Response to Phosphate Deficiency in Rice

2019 ◽  
Vol 20 (20) ◽  
pp. 5144
Author(s):  
Huwei Sun ◽  
Xiaoli Guo ◽  
Fugui Xu ◽  
Daxia Wu ◽  
Xuhong Zhang ◽  
...  
Keyword(s):  
Root Growth ◽  
Growth And Development ◽  
Plant Root ◽  
Lateral Roots ◽  
Root Hairs ◽  
Phosphate Deficiency ◽  
P Deficiency ◽  
Auxin Distribution ◽  
Seminal Roots ◽  
Underlying Mechanisms

The response of root architecture to phosphate (P) deficiency is critical in plant growth and development. Auxin is a key regulator of plant root growth in response to P deficiency, but the underlying mechanisms are unclear. In this study, phenotypic and genetic analyses were undertaken to explore the role of OsPIN2, an auxin efflux transporter, in regulating the growth and development of rice roots under normal nutrition condition (control) and low-phosphate condition (LP). Higher expression of OsPIN2 was observed in rice plants under LP compared to the control. Meanwhile, the auxin levels of roots were increased under LP relative to control condition in wild-type (WT) plants. Compared to WT plants, two overexpression (OE) lines had higher auxin levels in the roots under control and LP. LP led to increased seminal roots (SRs) length and the root hairs (RHs) density, but decreased lateral roots (LRs) density in WT plants. However, overexpression of OsPIN2 caused a loss of sensitivity in the root response to P deficiency. The OE lines had a shorter SR length, lower LR density, and greater RH density than WT plants under control. However, the LR and RH densities in the OE lines were similar to those in WT plants under LP. Compared to WT plants, overexpression of OsPIN2 had a shorter root length through decreased root cell elongation under control and LP. Surprisingly, overexpression of OsPIN2 might increase auxin distribution in epidermis of root, resulting in greater RH formation but less LR development in OE plants than in WT plants in the control condition but levels similar of these under LP. These results suggest that higher OsPIN2 expression regulates rice root growth and development maybe by changing auxin distribution in roots under LP condition.

scholarly journals Effect of salt and water stresses on growth, nitrogen and phosphorus metabolism in Cucumis sativus L. seedlings

2011 ◽  
Vol 77 (1) ◽  
pp. 27-33 ◽  
Author(s):  
Elżbieta Sacała ◽  
Edward Grzyś ◽  
Anna Demczuk ◽  
Zofia Spiak
Keyword(s):  
Salt Stress ◽  
Osmotic Stress ◽  
Cucumis Sativus ◽  
Nitrate Concentration ◽  
Dry Weight ◽  
Stress Factors ◽  
Fresh Mass ◽  
Nitrate Content ◽  
Cucumber Seedlings ◽  
Nr Activity

Plants exposed to osmotic stress exhibit changes in their physiology and metabolism. In general, osmotic stress reduces water availability and causes nutritional imbalance in plants. In the present study, we compared the response of cucumber (<em>Cucumis sativus</em> L. var. Władko F-1) to ionic (100 mmol•dm-3 NaCl) and osmotic stress (10% PEG 6000). Both stress factors reduced significantly fresh and dry weight of 7-day-old cucumber seedlings. Under PEG treatment reduction of cucumber dry mass was lesser than in fresh mass, whereas under salt stress decrease in dry weight of cucumber shoots was more pronounced than in fresh mass. Salt stress caused severe decrease in nitrate concentration and activity of nitrate reductase (NR). In cotyledons nitrate content declined to 17% of the control and similar reduction in NR activity was observed. In the roots, observed changes were not so drastic but there was also strong interaction between reduction in nitrate content and NR activity. Under 10% PEG both nitrate concentration and NR activity in cucumber roots were significantly higher in comparison to control plants. In cotyledons NR activity was significantly lower than in control plants, while decrease in nitrate content was not statistically significant. Phosphate concentration did not change significantly in cucumber cotyledons but increased in roots treated both NaCl (32% increase) and PEG (53% increase). Similar tendencies were observed in acid phosphatase activity. Obtained results indicated that osmotic and salt stresses evoke differential responses, particularly in growth reduction and nitrogen metabolism in cucumber seedlings.

scholarly journals Influence of sucrose starvation, osmotic and salt stresses on expression profiles of genes involved in the development of autophagy by means of microtubules

2018 ◽  
Vol 15 (2) ◽  
pp. 174-180 ◽  
Author(s):  
V. D. Olenieva ◽  
D. I. Lytvyn ◽  
A. I. Yemets ◽  
Ya. B. Blume
Keyword(s):  
Arabidopsis Thaliana ◽  
Salt Stress ◽  
Osmotic Stress ◽  
Transcriptome Analysis ◽  
Expression Profiles ◽  
Critical Role ◽  
Structural Units ◽  
Sucrose Starvation ◽  
Key Genes ◽  
Abiotic Stimuli

Aim. The aim of this work was to investigate changes in expression profiles of key genes involved in the development of autophagy by means of microtubules under the influence of sucrose starvation, osmotic and salt stresses. Methods. Arabidopsis thaliana seeds were sown aseptically on Murashige and Skoog solid medium. Salt and osmotic stresses were simulated by seed germination and seedlings cultivation on the media containing 150 mM NaCl and 10 mM mannitol, respectively. For investigation of starvation-induced autophagy plants were germinated and grown on sucrose-free medium. Results. Changes in expression of α-tubulin and atg8 genes had clearly defined stressdependent nature. Overexpression of tua1 and atg8e under starvation; tua3 and atg8f under osmotic stress; tua3 and atg8f, atg8e during salt stress indirectly testifies interaction between the structural units of autophagosomes and microtubules. It was shown that influence of investigated abiotic stimuli results in overexpression of elp3 and hda6 genes. Small increase in expression levels of hexokinase 2 and 3 was demonstrated. Conclusions. Transcriptome analysis of key genes involved in realization of autophagy induced by sucrose starvation, osmotic and salt stresses in Arabidopsis thaliana cells was conducted. Received data indirectly testifies interaction between the structural units of autophagosomes and microtubules and enables to point α-tubulin and atg8 genes, which are specific for the realization of autophagy induced by a certain abiotic stimuli. Expression profiles of elp3/deacetylases as well as hexokinases indicate the critical role of α-tubulin acetylation for autophagic response, that is involved in the development of programmed cell death.Keywords: autophagy, sucrose starvation, osmotic stress, salt stress, transcriptome analysis, α-tubulin, atg8.

Overexpression of wheat dehydrin DHN-5 enhances tolerance to salt and osmotic stress in Arabidopsis thaliana

2007 ◽  
Vol 26 (11) ◽  
pp. 2017-2026 ◽  
Author(s):  
Faïçal Brini ◽  
Moez Hanin ◽  
Victoria Lumbreras ◽  
Imen Amara ◽  
Habib Khoudi ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Osmotic Stress ◽  
Salt And Osmotic Stress

scholarly journals Influence of Salt Stress on the flg22 Induced ROS Production in Arabidopsis Thaliana Leaves

2019 ◽  
Author(s):  
Amrahov Nurlan Rashid ◽  
Martin Janda ◽  
Mammadov Ziaddin Mahmud ◽  
Olga Valentová ◽  
Lenka Burketová ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Salt Stress ◽  
Leaf Tissue ◽  
Tissue Response ◽  
Combined Effect ◽  
Stress Factors ◽  
Ros Production ◽  
High Concentration ◽  
Natural Habitats ◽  
The Impact

AbstractIn their natural habitats, plants have to cope with multiple stress factors triggering respective response pathways, leading to mutual interference. Our work aimed to study the effect of salt stress in combination with immune response triggered by microbe-associated molecular pattern (MAMP) in Arabidopsis thaliana Col-0 plants. We measured ROS production after treatment with flg22 and the influence of concomitant salt stress (NaCl and Na2CO3).The maximum combined effect of NaCl solution and flg22 on ROS production was achieved at 6 mM salt, which was almost 2 times higher than the single effect of MAMP. A similar maximum combined effect with Na2CO3 was observed at 10 mM concentration. High concentration of NaCl and Na2CO3 was accompanied with declining of ROS production, which was completely inhibited at 150 mM of NaCl and at 50 mM of Na2CO3.The immediate and long term (24 h) effect of NaCl on leaf tissue of Arabidopsis thaliana showed that the impact of salt stress on flg22induced ROS production probably did not affect the genetic aspects of the tissue response, but was associated with ionic and osmotic stresses. Experiments with mannitol, KCl and CaCl2 allowed to conclude that the observed effect was due to the ionic stress of the salt rather than the osmotic one.

scholarly journals SOS Yolağından Sorumlu Arabidopsis Mutantlarının Tuz Stresi Altındaki Hassasiyetlerinin Karşılaştırılması

2019 ◽  
Vol 7 (11) ◽  
pp. 1982
Author(s):  
Buasimuhan Abudureyimu ◽  
Emre Aksoy
Keyword(s):  
Salt Stress ◽  
Plant Root ◽  
Stress Factors ◽  
Control Mechanisms ◽  
Molecular Control ◽  
Abiotic Stress Factors ◽  
Low Levels ◽  
Stress Related Genes ◽  
Salt Overly Sensitive

Salinity stress is one of the most important and common abiotic stress factors that cause significant physiological and metabolic changes in plants, negatively affecting plant growth and development, and causing decrease in product quality and quantity. The elucidation of the molecular control mechanisms associated with salt stress tolerance is based on the activation and /or inactivation of various stress-related genes. Salt Overly Sensitive (SOS) tolerance mechanism under salt stress is of great importance in terms of salt tolerance of the plants. Although this mechanism has been studied for many years, the physiological changes that the plants give as a result of mutation of the genes in the pathway under different levels of sodium chloride (NaCl) during development have not been examined comparatively. In this study, we found that the Arabidopsis thaliana sos1-1 mutant plant showed sensitivity to 10 mM NaCl while the sos3-1 and hkt1-1 mutants showed tolerance. The sos1-1, sos3-1 and hkt1-1 mutants showed increasing sensitivity when NaCl was applied beyon 50 mM of concentration. In addition, plants did not show significant sensitivity for 1 day of stress application, while significant effects were observed in plant root length when exposed to salinity for 3 to 4 days. Col-0, hkt1-1 and sos3-1 roots treated with low levels of NaCl for a short term were positively affected in length. In the light of these results, the amount and duration of salt stress is very critical in Arabidopsis thaliana's responses to the stress and determination of molecular tolerance pathways.

Sign in / Sign up

Export Citation Format

Share Document