Stress Conditions Research Articles

Not all REITs are alike: modelling the dynamic connectedness of sectoral REITs and the US yield curve

ABSTRACT We model the dynamic connectedness between key sectoral REITs and the yield curve’s constituents. We employ both return and volatility of REITs and conduct analysis in static as well as time-varying framework. Our static analysis reveals Office REITs as the net spillover transmitter to the system, whiles Mortgage, Timber, and Infrastructure REITs are net recipients of return and volatility spillovers. We document that despite the high interdependencies between sectoral REITs, their response to return and volatility spillovers is heterogenic. Our findings divulge low idiosyncratic spillovers in sectoral REITs, suggesting that controlling the transmission and admission of exogeneous shocks need to be paramount to both investors and policymakers. Our dynamic analysis discloses the consistency of Industrial, Mortgage, and Timber REITs as diversifiers (safe havens) in tranquil (tumult) trading periods. We document contagion in the connectedness of sectoral REITs during crises periods. Therefore, timely policy actions in stressed market conditions are recommended to lessen the degree of effect on fundamental cross-sector linkages through contagion. We discuss the implications of our findings for portfolio management and market regulation.

Not all REITs are alike: modelling the dynamic connectedness of sectoral REITs and the US yield curve

ABSTRACT We model the dynamic connectedness between key sectoral REITs and the yield curve’s constituents. We employ both return and volatility of REITs and conduct analysis in static as well as time-varying framework. Our static analysis reveals Office REITs as the net spillover transmitter to the system, whiles Mortgage, Timber, and Infrastructure REITs are net recipients of return and volatility spillovers. We document that despite the high interdependencies between sectoral REITs, their response to return and volatility spillovers is heterogenic. Our findings divulge low idiosyncratic spillovers in sectoral REITs, suggesting that controlling the transmission and admission of exogeneous shocks need to be paramount to both investors and policymakers. Our dynamic analysis discloses the consistency of Industrial, Mortgage, and Timber REITs as diversifiers (safe havens) in tranquil (tumult) trading periods. We document contagion in the connectedness of sectoral REITs during crises periods. Therefore, timely policy actions in stressed market conditions are recommended to lessen the degree of effect on fundamental cross-sector linkages through contagion. We discuss the implications of our findings for portfolio management and market regulation.

Global, local, or glocal? Unravelling the interplay of geopolitical risks and financial stress

Since the start of the previous decade, regionalization of trade and investment flows has led to complex coupling in local (country-level) and global risks. To-date, little is known about how global uncertainty interacts with local uncertainty across the financial systems. Our study investigates the nexus between global and country-specific Geopolitical Risks (GPRs) and financial stress index (FSI) in five highly-open, large developed economies. We employ the cross-quantilogram and cross-spectral quantile coherency approaches on weekly data over 2000–2022 to show heterogeneous dependency of local and global geopolitical uncertainty on the financial stress conditions. Specifically, our results show that in the U.S. and the UK dependency of local and global geopolitical uncertainty on the financial stress conditions is influenced by the varying market conditions. In contrast, Canadian FSI is intensified by both global and country-level geopolitical risks, whereas German and French financial systems exhibit significant resilience to the global and local geopolitical shocks. Hence, the latter markets show hedging properties vis-a-vis global geopolitical risks.

Numerical simulation of blasting behavior of rock mass with cavity under high in-situ stress

With the shift of coal seam mining to the deep, the in-situ stress of coal and rock mass increases gradually. High ground stress can limit the generation of rock cracks caused by blasting, and blasting usually shows different crushing states than low stress conditions. In order to study the blasting expansion rule of rock mass with cavity under high ground stress and the rock mass fracture state under different side stress coefficients. In this paper, the effective range of blasting and the stress distribution under blasting load are analyzed theoretically. The RHT (Riedel-Hiermaier-Thoma) model is used to numerically simulate the blasting process of rock mass with cavity under different ground stress, and the influence of ground stress and lateral pressure coefficient on the crack growth of rock mass is studied. The results show that when there is no ground stress, the damage cracks in rock mass are more concentrated in the horizontal direction and the fracture development tends to the direction where the holes are located, which confirms the guiding effect and stress concentration effect of the holes in rock mass, which helps to promote the crack penetration between the hole and the hole. The length difference of horizontal and vertical damage cracks in rock mass increases with the increase of horizontal and vertical stress difference. Under the same lateral stress coefficient, the larger the horizontal and vertical stress difference is, the stronger the inhibition effect on crack formation is. For blasting of rock mass with high ground stress, the crack formation length between gun holes decreases with the increase of stress level, and the crack extends preferentially in the direction of higher stress. Therefore, the placement of gun holes along the direction of greater stress and the shortening of hole spacing are conducive to the penetration of cracks between gun holes and empty holes. The research can provide reference for rock breaking behavior of deep rock mass blasting.

Mitochondrial inorganic polyphosphate is required to maintain proteostasis within the organelle

The existing literature points towards the presence of robust mitochondrial mechanisms aimed at mitigating protein dyshomeostasis within the organelle. However, the precise molecular composition of these mechanisms remains unclear. Our data show that inorganic polyphosphate (polyP), a polymer well-conserved throughout evolution, is a component of these mechanisms. In mammals, mitochondria exhibit a significant abundance of polyP, and both our research and that of others have already highlighted its potent regulatory effect on bioenergetics. Given the intimate connection between energy metabolism and protein homeostasis, the involvement of polyP in proteostasis has also been demonstrated in several organisms. For example, polyP is a bacterial primordial chaperone, and its role in amyloidogenesis has already been established. Here, using mammalian models, our study reveals that the depletion of mitochondrial polyP leads to increased protein aggregation within the organelle, following stress exposure. Furthermore, mitochondrial polyP is able to bind to proteins, and these proteins differ under control and stress conditions. The depletion of mitochondrial polyP significantly affects the proteome under both control and stress conditions, while also exerting regulatory control over gene expression. Our findings suggest that mitochondrial polyP is a previously unrecognized, and potent component of mitochondrial proteostasis.

Enhancing neovascularization post-myocardial infarction through injectable hydrogel functionalized with endothelial-derived EVs.

Over the past three decades, cell therapy development has fallen short of expectations, with many cellular sources demonstrating a "Janus effect" and raising safety concerns. Extracellular vesicles (EVs), supported by advanced technologies, present a promising avenue in regenerative medicine, offering benefits such as immune tolerance and avoidance of negative aspects associated with cell transplants. Our previous research showcased enhanced and organized subcutaneous vascularization using three-dimensional bioprinted patches containing HUVEC-derived EVs in immunodeficient animal models. In this context, stress conditions on the cells of origin further boosted the EVs' neoangiogenic potential. Since neovascularization is the first regenerative target requiring restoration, the present study aims to complement our previous work by employing an injectable gelatin methacrylate (GelMA) hydrogel functionalized with HUVEC-derived EVs in a pathological condition of acute myocardial infarction. This bioactive hydrogel resulted in reduced fibrosis, improved contractility, and promoted angiogenesis, showing promise in countering tissue deterioration and addressing vascular deficits. Moreover, the molecular characterization of EVs through miRNome and proteomic analyses further supports their potential as bio-additives for hydrogel functionalization. This cell-free approach mitigates immune rejection and oncogenic risks, offering innovative therapeutic advantages.

Unravelling drought and salinity stress responses in barley genotypes: physiological, biochemical, and molecular insights

In the face of escalating environmental challenges, understanding crop responses to abiotic stress is pivotal for sustainable agriculture. The present study meticulously investigates the intricate interplay between drought and salinity stress in barley (Hordeum vulgare L.). Employing three distinct barley genotypes—Traveller, Prunella, and Zahna—we scrutinize their physiological, biochemical, and molecular adaptations under stress conditions. Our findings underscore genotype-specific responses, unravelling the multifaceted mechanisms that govern stress tolerance. Chlorophyll content, a vital indicator of photosynthetic efficiency, exhibits significant variations across genotypes. Salinity stress induces a decline in chlorophyll levels, while drought stress triggers a more nuanced response. Stomatal conductance, a key regulator of water loss, also diverges among the genotypes. Traveller displays remarkable stomatal closure under drought, conserving water, whereas Prunella and Zahna exhibit contrasting patterns. Antioxidant enzyme activities, crucial for combating oxidative stress, fluctuate significantly. Activities of superoxide dismutase (SOD) and catalase (CAT) surge under salinity stress, while drought predominantly impacts SOD. Gene expression profiling reveals genotype-specific signatures, with stress-responsive genes modulating adaptive pathways. Correlation analyses revealed the intricate interplay of the physiological and biochemical parameters. Genotype-specific adaptations, coupled with dynamic physiological and molecular responses, underscore the plasticity of barley’s stress tolerance mechanisms. Throughout the study, the Zahna genotype demonstrated notable tolerance in terms of performance. These insights hold promise for breeding resilient cultivars, bolstering food security in an increasingly unpredictable climate. By deciphering the barley stress symphony, we contribute to the harmonious orchestration of sustainable agricultural practices.

An end-to-end approach for single-cell infrared absorption spectroscopy of bacterial inclusion bodies: from AFM-IR measurement to data interpretation of large sample sets

BackgroundInclusion bodies (IBs) are well-known subcellular structures in bacteria where protein aggregates are collected. Various methods have probed their structure, but single-cell spectroscopy remains challenging. Atomic Force Microscopy-based Infrared Spectroscopy (AFM-IR) is a novel technology with high potential for the characterisation of biomaterials such as IBs.ResultsWe present a detailed investigation using AFM-IR, revealing the substructure of IBs and their variation at the single-cell level, including a rigorous optimisation of data collection parameters and addressing issues such as laser power, pulse frequency, and sample drift. An analysis pipeline was developed tailored to AFM-IR image data, allowing high-throughput, label-free imaging of more than 3500 IBs in 12,000 bacterial cells. We examined IBs generated in Escherichia coli under different stress conditions. Dimensionality reduction analysis of the resulting spectra suggested distinct clustering of stress conditions, aligning with the nature and severity of the applied stresses. Correlation analyses revealed intricate relationships between the physical and morphological properties of IBs.ConclusionsOur study highlights the power and limitations of AFM-IR, revealing structural heterogeneity within and between IBs. We show that it is possible to perform quantitative analyses of AFM-IR maps over a large collection of different samples and determine how to control for various technical artefacts.

Proposed formulas for pillar stress estimation in a regular room-and-pillar pattern

Room-and-pillar mining is one of the oldest and most widely employed underground mining methods worldwide, while in recent years it has also been used for civil engineering projects and applications. The pillar design process is quite straightforward, requiring the assessment of two key elements, namely the pillar's strength and the anticipated loading imposed on it. Lots of research work has been elaborated for the estimation of pillars' strength and the main parameters associated with it, while, on the other hand, in terms of the loading the Tributary Area Theory (TAT) has been traditionally and successfully used as the dominant methodology to assess the post-mining pillar induced stresses. This paper focuses primarily on decoding the pillar loading regime by analyzing the identifying the stresses imposed to them through the use of modern computational tools offered by 2D and 3D numerical analyses, over a series of pillars' type (square, ribs), configurations and initial virgin stress fields. This allows for the development of a benchmarking framework that showcase the differences in the stress conditions and reveal the over-conservative behavior of TAT. More importantly though, it allowed for the expression of two (2) general analytical formulae for the direct estimation of the average vertical elastic stresses on pillars, both for the case of rib & square pillars layout; the most typical patterns applied in this method. They aim at providing an easy to use and more accurate estimation of the pillar stress - as compared to TAT - in alignment with the results obtained from numerical analyses. Thus, with the proposed formulas, the time-consuming numerical process needed for preliminary pillars' dimensioning is tackled in a swift and effective manner.

Levels of Corticosterone and Glucose in Blood of Rats under Conditions of Chronic Unpredictable Stress of Different Duration

INTRODUCTION: Mammals are almost constantly exposed to a variety of stressors. The changes in the concentration of corticosterone and the level of glucose in blood of animals under such conditions seems relevant for understanding the influence of repeated stress effects on endocrine and metabolic processes. AIM: To study the concentrations of corticosterone and glucose in blood of rats in different time periods of prolonged low-intensity unpredictable stress. MATERIALS AND METHODS: Experiments were carried out on 42 male Wistar rats. Individuals of the experimental groups were subjected to 7-day cycles of alternating stressors using a modified model of chronic unpredictable mild stress with presentation of different stressors. The concentration of corticosterone and glucose in blood was determined at 1, 2, 3 and 4 weeks of observation. RESULTS: A pronounced decrease in corticosterone levels was found in rats at 1 week of stress exposure, followed by a slow recovery by the end of 4th week. Blood glucose level increased at 2 weeks of exposure. CONCLUSION: The data obtained illustrate the specificity of changes in the levels of glucose and corticosterone in the blood of mammals in different time periods of chronic stress. These changes characterize the dysregulation of the integrative physiological systems in relatively early periods of chronic stress with the subsequent development of adaptation in the later stages of repeated stress exposures.

Levels of Corticosterone and Glucose in Blood of Rats under Conditions of Chronic Unpredictable Stress of Different Duration

INTRODUCTION: Mammals are almost constantly exposed to a variety of stressors. The changes in the concentration of corticosterone and the level of glucose in blood of animals under such conditions seems relevant for understanding the influence of repeated stress effects on endocrine and metabolic processes. AIM: To study the concentrations of corticosterone and glucose in blood of rats in different time periods of prolonged low-intensity unpredictable stress. MATERIALS AND METHODS: Experiments were carried out on 42 male Wistar rats. Individuals of the experimental groups were subjected to 7-day cycles of alternating stressors using a modified model of chronic unpredictable mild stress with presentation of different stressors. The concentration of corticosterone and glucose in blood was determined at 1, 2, 3 and 4 weeks of observation. RESULTS: A pronounced decrease in corticosterone levels was found in rats at 1 week of stress exposure, followed by a slow recovery by the end of 4th week. Blood glucose level increased at 2 weeks of exposure. CONCLUSION: The data obtained illustrate the specificity of changes in the levels of glucose and corticosterone in the blood of mammals in different time periods of chronic stress. These changes characterize the dysregulation of the integrative physiological systems in relatively early periods of chronic stress with the subsequent development of adaptation in the later stages of repeated stress exposures.

A dwarf conifer tree from the Triassic of Antarctica: the first fossil evidence of suppressed growth in a favorable climate?

The complexity of fossil forest ecosystems is difficult to reconstruct due to the fragmentary nature of the fossil record. However, detailed morpho-anatomical studies of well-preserved individual fossils can provide key information on tree growth and ecology, including in biomes with no modern analog such as the lush forests that developed in the polar regions during past greenhouse climatic episodes. We describe an unusual-looking stem from Middle Triassic (ca 240 Ma) deposits of Antarctica with over 100 very narrow growth-rings and conspicuous persistent vascular traces through the wood. Sections of the specimen were prepared using the cellulose acetate peel technique to determine its systematic affinities and analyse its growth. The new fossil shows similarities with the form genus Woodworthia and with conifer stems from the Triassic of Antarctica, and is assigned to the conifers. Vascular traces are interpreted as those of small branches retained on the trunk. Growth-ring analyses reveal one of the slowest growth rates reported in the fossil record, with an average of 0.2mm/season. While the tree was growing within the Triassic polar circle, sedimentological data and growth-ring information from other fossil trees, including from the same locality, support the presence of favorable conditions in the region. The specimen is interpreted as a dwarf conifer tree that grew under a generally favorable regional climate but whose growth was suppressed due to stressful local site conditions. This is the first time that a tree with suppressed growth is identified as such in the fossil record, providing new insights on the structure of polar forests under greenhouse climates and, more generally, on the complexity of tree communities in deep time.

A dwarf conifer tree from the Triassic of Antarctica: the first fossil evidence of suppressed growth in a favorable climate?

The complexity of fossil forest ecosystems is difficult to reconstruct due to the fragmentary nature of the fossil record. However, detailed morpho-anatomical studies of well-preserved individual fossils can provide key information on tree growth and ecology, including in biomes with no modern analog such as the lush forests that developed in the polar regions during past greenhouse climatic episodes. We describe an unusual-looking stem from Middle Triassic (ca 240 Ma) deposits of Antarctica with over 100 very narrow growth-rings and conspicuous persistent vascular traces through the wood. Sections of the specimen were prepared using the cellulose acetate peel technique to determine its systematic affinities and analyse its growth. The new fossil shows similarities with the form genus Woodworthia and with conifer stems from the Triassic of Antarctica, and is assigned to the conifers. Vascular traces are interpreted as those of small branches retained on the trunk. Growth-ring analyses reveal one of the slowest growth rates reported in the fossil record, with an average of 0.2mm/season. While the tree was growing within the Triassic polar circle, sedimentological data and growth-ring information from other fossil trees, including from the same locality, support the presence of favorable conditions in the region. The specimen is interpreted as a dwarf conifer tree that grew under a generally favorable regional climate but whose growth was suppressed due to stressful local site conditions. This is the first time that a tree with suppressed growth is identified as such in the fossil record, providing new insights on the structure of polar forests under greenhouse climates and, more generally, on the complexity of tree communities in deep time.

Foliar spray of glycine-chelated zinc (Zn) and iron (Fe) lowered the effect of macronutrient deficiencies and enhanced rice yield components, yield, and grain biofortification

The current investigation amid the alleviating of the macronutrient [Nitrogen (N), Phosphorus (P), and Potassium (K)] deficiency effects on rice yield, yield components, and grain biofortification by foliar spraying of Zn and Fe chelated by glycine amino acid (ZFCG) on the flooded rice conditions. Three-factor factorial experiment was conducted based on a randomized complete block design with three replications. The experimental factors were: macronutrients [Nitrogen (N), Phosphorous (P), and Potassium (K)] soil application at two levels (100 and 50% of the recommended dose) and foliar application of ZFCG during the booting and ripening stages at three levels (0, 1, and 1.5 kg ha−1). The results clearly showed that the foliar spraying of 1.5 kg ha−1 ZFCG significantly increased the growth characters, yield attributes, yields, and white rice nutritional quality of Hashemi cultivar both at the application of 100% (normal condition) and 50% (nutrient stresses condition) of the recommended rate of NPK. The foliar application of 1.5 kg ha−1 ZFCG increased the rice grain, straw, biological yield, head rice yield, and harvest index of the plots that received 50% of the recommended rate by about 14.6, 10.12, 50, 7.5, and 6.7% compared to the values of the control plots (no adding the NPK), respectively and 49.25, 31.21, 31.60, and 16.67% at the plots that received 100% of recommended NPK, respectively. Moreover, the foliar application of glycine amino acid-Fe and Zn chelate at two vital rice growth stages increased the value of the Zn, Fe and protein content of white rice at the plots that received 1/2 of the recommended dose of NPK by about 52.37%, 2 times, and 8.64% compared to control plots, respectively, and also 20.77%, 2 times, and 12% at the plots that received 100% of recommended NPK, respectively. The observed values are close to their values in those plots that have received 100% of recommended rate of NPK without foliar application. Therefore, it can be concluded that the foliar co-application of 1.5 kg ha−1 ZFCG during the two important rice growth stages (booting and ripening) might both alleviate the improper and imbalanced macronutrient deficiency stresses and enhance the rice grain yield and biofortification at flooded rice cultivation.

Mechanistic insights of salicylic acid-mediated salt stress tolerance in Zea mays L. seedlings

Elevated sodium level (Na+) poses significant threat to crop plant physio-biochemical processes, leading to impaired growth followedby decline in productivity. Addressing this challenge, requires an eco-friendly and cost-effective strategy that enhances plant salt stress tolerance capacity. In this context, the exogenous source of plant growth regulators (PGRs) proved to be an efficient approach. Of various PGRs, salicylic acid (SA) is an emerging signaling molecule that boosts plant stress endurance mechanism. This study investigates SA-mediated salt stress tolerance in maize (Zea mays L.) seedlings, by examining morpho-physiological and biochemical traits. Maize seedlings were subjected to varying levels of salt stress (0, 25, 50, 75, 100, and 150 mM NaCl) for a period of 10-days. The results revealed that, a substantial decline in germination percentage, shoot and root length, plant biomass, vigour index, and various other physiological parameters under salt stress causing concentrations. Conversely, salt stress increased oxidative stress indicators, including hydrogen peroxide (H2O2) and malondialdehyde (MDA), osmolytes and elemental concentrations as well as antioxident enzymes (SOD, CAT, POX, APX, GR, AsA). However, the exogenous supplementation of SA at 0.1 mM significantly restored most morpho-physiological attributes in maize under salt stress conditions. This suggests that SA actively triggers the ascorbate-glutathione (AsA-GSH) pathway and other key enzymes, leading to sodium extrusion and improving antioxidant defense in maize seedlings. This finding provides valuable insights for maize farmers that employing SA could lead to improved maize production in saline soils.

The interaction between the import carrier Hikeshi and HSP70 is modulated by heat, facilitating the nuclear import of HSP70 under heat stress conditions.

Heat stress strongly triggers the nuclear localization of the molecular chaperone HSP70. Hikeshi functions as a unique nuclear import carrier of HSP70. However, how the nuclear import of HSP70 is activated in response to heat stress remains unclear. Here, we investigated the effects of heat on the nuclear import of HSP70. In vitro transport assays revealed that pretreatment of the test samples with heat facilitated the nuclear import of HSP70. Furthermore, binding of Hikeshi to HSP70 increased when temperatures rose. These results indicated that heat is one of the factors that activates the nuclear import of HSP70. Previous studies showed that the F97A mutation in Hikeshi in an extended loop induced an opening in the hydrophobic pocket and facilitated the translocation of Hikeshi through the nuclear pore complex. We found that nuclear accumulation of HSP70 occurred at a lower temperature in cells expressing the Hikeshi-F97A mutant than in cells expressing wild-type Hikeshi. Collectively, our results show that the movement of the extended loop may play an important role in the interaction of Hikeshi with both FG (phenylalanine-glycine)-nucleoporins and HSP70 in a temperature-dependent manner, resulting in the activation of nuclear import of HSP70 in response to heat stress.

Morpho-physiological characterization and selection of heat tolerant wheat lines using selection indices

Heat stress is one of the major constraints in wheat production due to its adverse effect on grain yield and component traits. Moreover, it negatively affects the physiological, biochemical and quality traits of wheat. Therefore, selection of heat tolerant wheat lines is one of the major breeding goals for wheat scientist. In present study, 238 recombinant inbred lines were evaluated along with their parents WH 711 × WH 542 under timely and late sown (heat stress) condition. The heat tolerance indices were calculated based on grain yield under normal and stress conditions. The mean grain yield of 238 wheat lines was reduced by 20.54% suggesting critical effect of heat stress on grain yield. The harmonic mean (HM), stress tolerance index (STI), mean productivity (MP), geometric mean productivity (GMP), and mean relative performance (MRP) were correlated significantly and positively with grain yield under stress and normal conditions. Whereas, Tolerance index (TOL) was correlated negatively with grain yield under stress conditions and positively under normal condition. Based on STI, MP, HM, GMP and MRP, wheat lines WL 92, WL 119, WL 114, WL 110, WL 6 were identified as heat tolerant and could be utilized as potential lines for increasing heat stress tolerance of future wheat breeding programs.

Morpho-physiological characterization and selection of heat tolerant wheat lines using selection indices

Heat stress is one of the major constraints in wheat production due to its adverse effect on grain yield and component traits. Moreover, it negatively affects the physiological, biochemical and quality traits of wheat. Therefore, selection of heat tolerant wheat lines is one of the major breeding goals for wheat scientist. In present study, 238 recombinant inbred lines were evaluated along with their parents WH 711 × WH 542 under timely and late sown (heat stress) condition. The heat tolerance indices were calculated based on grain yield under normal and stress conditions. The mean grain yield of 238 wheat lines was reduced by 20.54% suggesting critical effect of heat stress on grain yield. The harmonic mean (HM), stress tolerance index (STI), mean productivity (MP), geometric mean productivity (GMP), and mean relative performance (MRP) were correlated significantly and positively with grain yield under stress and normal conditions. Whereas, Tolerance index (TOL) was correlated negatively with grain yield under stress conditions and positively under normal condition. Based on STI, MP, HM, GMP and MRP, wheat lines WL 92, WL 119, WL 114, WL 110, WL 6 were identified as heat tolerant and could be utilized as potential lines for increasing heat stress tolerance of future wheat breeding programs.

Exogenous Sodium Nitroprusside Affects the Redox System of Wheat Roots Differentially Regulating the Activity of Antioxidant Enzymes under Short-Time Osmotic Stress

Nitric oxide (NO) is a multifunctional signalling molecule involved in the regulation of plant ontogenesis and adaptation to different adverse environmental factors, in particular to osmotic stress. Understanding NO-induced plant protection is important for the improvement of plant stress tolerance and crop productivity under global climate changes. The root system is crucial for plant survival in a changeable environment. Damages that it experiences under water deficit conditions during the initial developmental periods seriously affect the viability of the plants. This work was devoted to the comparative analysis of the pretreatment of wheat seedlings through the root system with NO donor sodium nitroprusside (SNP) for 24 h on various parameters of redox homeostasis under exposure to osmotic stress (PEG 6000, 12%) over 0.5–24 h. The active and exhausted solutions of SNP, termed as (SNP/+NO) and (SNP/−NO), respectively, were used in this work at a concentration of 2 × 10−4 M. Using biochemistry and light microscopy methods, it has been revealed that osmotic stress caused oxidative damages and the disruption of membrane cell structures in wheat roots. PEG exposure increased the production of superoxide (O2•−), hydrogen peroxide (H2O2), malondialdehyde (MDA), and the levels of electrolyte leakage (EL) and lipid peroxidation (LPO). Stress treatment enhanced the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), the excretion of proline, and the rate of cell death and inhibited their division. Pretreatment with (SNP/+NO) decreased PEG-induced root damages by differently regulating the antioxidant enzymes under stress conditions. Thus, (SNP/+NO) pretreatment led to SOD, APX, and CAT inhibition during the first 4 h of stress and stimulated their activity after 24 h of PEG exposure when compared to SNP-untreated or (SNP/−NO)-pretreated and stress-subjected plants. Osmotic stress triggered the intense excretion of proline by roots into the external medium. Pretreatment with (SNP/+NO) in contrast with (SNP/−NO) additionally increased stress-induced proline excretion. Our results indicate that NO is able to mitigate the destructive effects of osmotic stress on the roots of wheat seedlings. However, the mechanisms of NO protective action may be different at certain periods of stress exposure.

Neurodevelopmental disorder-associated CYFIP2 regulates membraneless organelles and eIF2α phosphorylation via protein interactors and actin cytoskeleton.

De novo variants in the Cytoplasmic FMR1-interacting protein 2 (CYFIP2) have been repeatedly associated with neurodevelopmental disorders and epilepsy, underscoring its critical role in brain development and function. While CYFIP2's role in regulating actin polymerization as part of the WAVE regulatory complex (WRC) is well-established, its additional molecular functions remain relatively unexplored. In this study, we performed unbiased quantitative proteomic analysis, revealing 278 differentially expressed proteins (DEPs) in the forebrain of Cyfip2 knock-out embryonic mice compared to wild-type mice. Unexpectedly, these DEPs, in conjunction with previously identified CYFIP2 brain interactors, included not only other WRC components but also numerous proteins associated with membraneless organelles (MLOs) involved in mRNA processing and translation within cells, including the nucleolus, stress granules, and processing bodies. Additionally, single-cell transcriptomic analysis of the Cyfip2 knock-out forebrain revealed gene expression changes linked to cellular stress responses and MLOs. We also observed morphological changes in MLOs in Cyfip2 knock-out brains and CYFIP2 knock-down cells under basal and stress conditions. Lastly, we demonstrated that CYFIP2 knock-down in cells, potentially through WRC-dependent actin regulation, suppressed the phosphorylation levels of the alpha subunit of eukaryotic translation initiation factor 2 (eIF2α), thereby enhancing protein synthesis. These results suggest a physical and functional connection between CYFIP2 and various MLO proteins and also extend CYFIP2's role within the WRC from actin regulation to influencing eIF2α phosphorylation and protein synthesis. With these dual functions, CYFIP2 may fine-tune the balance between MLO formation/dynamics and protein synthesis, a crucial aspect of proper mRNA processing and translation.