Stress Adaptation Processes Research Articles

Lack of Mitochondrial DNA Provides Metabolic Advantage in Yeast Osmoadaptation

Alterations in mitochondrial function have been linked to a variety of cellular and organismal stress responses including apoptosis, aging, neurodegeneration and tumorigenesis. However, adaptation to mitochondrial dysfunction can occur through the activation of survival pathways, whose mechanisms are still poorly understood. The yeast Saccharomyces cerevisiae is an invaluable model organism for studying how mitochondrial dysfunction can affect stress response and adaptation processes. In this study, we analyzed and compared in the absence and in the presence of osmostress wild-type cells with two models of cells lacking mitochondrial DNA: ethidium bromide-treated cells (ρ0) and cells lacking the mitochondrial pyrimidine nucleotide transporter RIM2 (ΔRIM2). Our results revealed that the lack of mitochondrial DNA provides an advantage in the kinetics of stress response. Additionally, wild-type cells exhibited higher osmosensitivity in the presence of respiratory metabolism. Mitochondrial mutants showed increased glycerol levels, required in the short-term response of yeast osmoadaptation, and prolonged oxidative stress. The involvement of the mitochondrial retrograde signaling in osmoadaptation has been previously demonstrated. The expression of CIT2, encoding the peroxisomal isoform of citrate synthase and whose up-regulation is prototypical of RTG pathway activation, appeared to be increased in the mutants. Interestingly, selected TCA cycle genes, CIT1 and ACO1, whose expression depends on RTG signaling upon stress, showed a different regulation in ρ0 and ΔRIM2 cells. These data suggest that osmoadaptation can occur through different mechanisms in the presence of mitochondrial defects and will allow us to gain insight into the relationships among metabolism, mitochondria-mediated stress response, and cell adaptation.

Genetic variability of aquaporin expression in maize: From eQTLs to a MITE insertion regulating PIP2;5 expression.

Plant aquaporins are involved in numerous physiological processes, such as cellular homeostasis, tissue hydraulics, transpiration, and nutrient supply, and are key players of the response to environmental cues. While varying expression patterns of aquaporin genes have been described across organs, developmental stages, and stress conditions, the underlying regulation mechanisms remain elusive. Hence, this work aimed to shed light on the expression variability of 4 plasma membrane intrinsic protein (PIP) genes in maize (Zea mays) leaves, and its genetic causes, through expression quantitative trait locus (eQTL) mapping across a 252-hybrid diversity panel. Significant genetic variability in PIP transcript abundance was observed to different extents depending on the isoforms. The genome-wide association study mapped numerous eQTLs, both local and distant, thus emphasizing the existing natural diversity of PIP gene expression across the studied panel and the potential to reveal regulatory actors and mechanisms. One eQTL associated with PIP2;5 expression variation was characterized. Genomic sequence comparison and in vivo reporter assay attributed, at least partly, the local eQTL to a transposon-containing polymorphism in the PIP2;5 promoter. This work paves the way to the molecular understanding of PIP gene regulation and its possible integration into larger networks regulating physiological and stress adaptation processes.

Hsf1 and the molecular chaperone Hsp90 support a 'rewiring stress response' leading to an adaptive cell size increase in chronic stress.

Cells are exposed to a wide variety of internal and external stresses. Although many studies have focused on cellular responses to acute and severe stresses, little is known about how cellular systems adapt to sublethal chronic stresses. Using mammalian cells in culture, we discovered that they adapt to chronic mild stresses of up to two weeks, notably proteotoxic stresses such as heat, by increasing their size and translation, thereby scaling the amount of total protein. These adaptations render them more resilient to persistent and subsequent stresses. We demonstrate that Hsf1, well known for its role in acute stress responses, is required for the cell size increase, and that the molecular chaperone Hsp90 is essential for coupling the cell size increase to augmented translation. We term this translational reprogramming the 'rewiring stress response', and propose that this protective process of chronic stress adaptation contributes to the increase in size as cells get older, and that its failure promotes aging.

Hsf1 and the molecular chaperone Hsp90 support a ‘rewiring stress response’ leading to an adaptive cell size increase in chronic stress

Cells are exposed to a wide variety of internal and external stresses. Although many studies have focused on cellular responses to acute and severe stresses, little is known about how cellular systems adapt to sublethal chronic stresses. Using mammalian cells in culture, we discovered that they adapt to chronic mild stresses of up to two weeks, notably proteotoxic stresses such as heat, by increasing their size and translation, thereby scaling the amount of total protein. These adaptations render them more resilient to persistent and subsequent stresses. We demonstrate that Hsf1, well known for its role in acute stress responses, is required for the cell size increase, and that the molecular chaperone Hsp90 is essential for coupling the cell size increase to augmented translation. We term this translational reprogramming the ‘rewiring stress response’, and propose that this protective process of chronic stress adaptation contributes to the increase in size as cells get older, and that its failure promotes aging.

The Effect of Stress Hormones, Ultraviolet C, and Stilbene Precursors on Expression of Calcineurin B-like Protein (CBL) and CBL-Interacting Protein Kinase (CIPK) Genes in Cell Cultures and Leaves of Vitis amurensis Rupr

Calcium serves as a crucial messenger in plant stress adaptation and developmental processes. Plants encode several multigene families of calcium sensor proteins with diverse functions in plant growth and stress responses. Several studies indicated that some calcium sensors may be involved in the regulation of secondary metabolite production in plant cells. The present study aimed to investigate expression of calcineurin B-like proteins (CBL) and CBL-interacting protein kinase (CIPK) in response to conditions inducting biosynthesis of stilbenes in grapevine. We investigated CBL and CIPK gene expression in wild-growing grapevine Vitis amurensis Rupr., known as a rich stilbene source, in response to the application of stilbene biosynthesis-inducing conditions, including application of stress hormones (salicylic acid or SA, methyl jasmonate or MeJA), phenolic precursors (p-coumaric acids or CA), and ultraviolet irradiation (UV-C). The influence of these effectors on the levels of 13 VaCBL and 27 VaCIPK mRNA transcripts as well as on stilbene production was analyzed by quantitative real-time RT-PCR in the leaves and cell cultures of V. amurensis. The data revealed that VaCBL4-1 expression considerably increased after UV-C treatment in both grapevine cell cultures and leaves. The expression of VaCIPK31, 41-1, and 41-2 also increased, but this increase was mostly detected in cell cultures of V. amurensis. At the same time, expression of most VaCBL and VaCIPK genes was markedly down-regulated both in leaves and cell cultures of V. amurensis, which may indicate that the CBLs and CIPKs are involved in negative regulation of stilbene accumulation (VaCBL8, 10a-2, 10a-4, 11, 12, VaCIPK3, 9-1, 9-2, 12, 21-1, 21-2, 33, 34, 35, 36, 37, 39, 40, 41-3, 41-4). The results obtained provide new information of CBL and CIPK implication in the regulation of plant secondary metabolism in response to stress hormones, metabolite precursors, and UV-C irradiation.

Structural and functional changes in the kidneys of rats with toxic nephropathy after a course of drinking mineral water «DONAT Mg»

Kidney disease of various etiologies affects 6-7% of the total population of the globe. Glomerulonephritis and nephropathy of various etiologies make up a significant part of these kidney lesions. Infectious and non-infectious glomerulonephritis and nephropathy are distinguished, the latter are associated with the influence of environmental factors, including toxic substances, heavy metals and even medications.
 Magnesium is considered one of the components of the body's stress-limiting system, since all its effects are aimed at reducing the manifestations of stress and normalizing adaptation processes.
 A comparative assessment of changes in the kidneys during the simulation of toxic nephropathy and the influence of magnesium-containing agents on the course of the pathology of the experimental model was carried out.

The multifaceted roles of heterotrimeric G-proteins: lessons from models and crops

The review summarizes our advanced understanding of the heterotrimeric G-protein research from model plants and their emerging roles in modulating various plant architecture and agronomical traits in crop species. Heterotrimeric G-proteins (hereafter G-proteins), consisting of G-alpha(Gα), G-beta (Gβ) and G-gamma (Gγ) subunits, are key signal transducers conserved across different forms of life. The discovery of plant lineage-specific G-protein components (extra-large G-proteins and type-C Gγsubunits), inherent polyploidy in angiosperms, and unique modes of G-protein cycle regulation in plants pointed out to a few fundamental differences of plant G-protein signaling from its animal counterpart. Over the last 2 decades, extensive studies in the model plant Arabidopsis thaliana have confirmed the involvement of G-proteins in a wide range of plant growth and development, and stress adaptation processes. The G-protein research in crop species, however, is still in its infancy, and a handful of studies suggest important roles of G-proteins in regulating plant architectural and key agronomical traits including plant's response to abiotic and biotic factors. We propose that the advancement made in plant G-proteins research will facilitate the development of novel approaches to manage plant yield and fitness in changing environments.

Family demands and satisfaction with family life during the COVID-19 pandemic.

Based upon theories that describe the process of family stress adaptation, we model changes in family demands and satisfaction with family life during the COVID-19 pandemic among a sample of n = 1,042 respondents from Germany. Moreover, based on ecological perspectives on the role of family context, we consider partnership status and parental status as predictors of changes in these variables over time. Using a longitudinal research design, we model co-occurring trajectories of changes in family demands and satisfaction with family life between early April 2020 and early September 2020 using unconditional and conditional multivariate latent growth curve modeling. Results suggest that, on average, both family demands and satisfaction with family life increased across this time period and that having minor children ≤ 17 years of age was associated with decreases in satisfaction with family life across time. Moreover, an exploratory analysis suggests that partnership status may help offset the positive relationship between parental status and family demands. These findings have implications for future research on family life during a crisis and suggest that single parents of young children should be the focus of interventions to reduce family-related stressors and increase levels of family wellbeing during times of crisis. (PsycInfo Database Record (c) 2021 APA, all rights reserved) © 2021 American Psychological Association

Epigenetic regulation of salinity stress responses in cereals.

Cereals are important crops and are exposed to various types of environmental stresses that affect the overall growth and yield. Among the various abiotic stresses, salt stress is a major environmental factor that influences the genetic, physiological, and biochemical responses of cereal crops. Epigenetic regulation which includes DNA methylation, histone modification, and chromatin remodelling plays an important role in salt stress tolerance. Recent studies in rice genomics have highlighted that the epigenetic changes are heritable and therefore can be considered as molecular signatures. An epigenetic mechanism under salinity induces phenotypic responses involving modulations in gene expression. Association between histone modification and altered DNA methylation patterns and differential gene expression has been evidenced for salt sensitivity in rice and other cereal crops. In addition, epigenetics also creates stress memory that helps the plant to better combat future stress exposure. In the present review, we have discussed epigenetic influences in stress tolerance, adaptation, and evolution processes. Understanding the epigenetic regulation of salinity could help for designing salt-tolerant varieties leading to improved crop productivity.

Effects of Nitrogen and Phosphorus Limitation on Fatty Acid Contents in Aspergillus oryzae.

Aspergillus oryzae, commonly known as koji mold, has been widely used for the large-scale production of food products (sake, makgeolli, and soy sauce) and can accumulate a high level of lipids. In the present study, we showed the dynamic changes in A. oryzae mycelium growth and conidia formation under nitrogen and phosphorus nutrient stress. The fatty acid profile of A. oryzae was determined and the content of unsaturated fatty acid was found increased under nitrogen and phosphorus limitation. Oleic acid (C18:1), linoleic acid (C18:2), and γ-linolenic acid (C18:3) production were increased on five nitrogen and phosphorus limitation media, especially on nitrogen deep limitation and phosphorus limitation group, showing a 1. 2–, 1. 6–, and 2.4-fold increment, respectively, compared with the control. Transcriptomic analysis showed the expression profile of genes related to nitrogen metabolism, citrate cycle, and linoleic acid synthesis, resulting in the accumulation of unsaturated fatty acid. qRT-PCR results further confirmed the reliability and availability of the differentially expressed genes obtained from the transcriptome analysis. Our study provides a global transcriptome characterization of the nitrogen and phosphorus nutrient stress adaptation process in A. oryzae. It also revealed that the molecular mechanisms of A. oryzae respond to nitrogen and phosphorus stress. Our finding facilitates the construction of industrial strains with a nutrient-limited tolerance.

Cytochrome P450 Superfamily: Evolutionary and Functional Divergence in Sorghum (Sorghum bicolor) Stress Resistance.

Cytochrome P450 (CYP) genes encode enzymes that catalyze various growth-, development-, and stress-related reactions. Sorghum (Sorghum bicolor) is a type of C4 plant and an important cash crop. However, systematic identification and analysis of functional differentiation and evolution of CYP genes have not been carried out in this species. In the present study, we revealed that the sorghum genome contains 351 CYP genes, which can be divided into nine classes. These genes are from ancestors and repeated segments, rather than tandem repeats. Based on collinearity results, a large number of CYPs were extended before cotyledon differentiation, during the emergence of Gramineae, suggesting that genomewide duplication events and stress adaptation processes were important for the expansion of CYP genes. Their gene structure and motifs contain conserved regions and include various changes and loci. The expression characteristics and functional annotation of CYP genes indicated tissue specificity and selective expression. Overall, we identified all CYP genes in the sorghum genome and preliminarily explored their naming, structure, evolution, expression, and functional differentiation. The results advanced our understanding of plant gene family evolution and functional differentiation.

Vitamin A5/X controls stress-adaptation and prevents depressive-like behaviors in a mouse model of chronic stress

9-cis-13,14-dihydroretinoic acid (9CDHRA), acts as an endogenous ligand of the retinoid X receptors (RXRs), and is an active form of a suggested new vitamin, vitamin A5/X. Nutritional-relevance of this pathway as well as its detailed role in vertebrate physiology, remain largely unknown. Since recent GWAS data and experimental studies associated RXR-mediated signaling with depression, we explored here the relevance of RXR and vitamin A5/X-mediated signaling in the control of stress adaptation and depressive-like behaviors in mice. We found that compromised availability of 9CDHRA in Rbp1−/− mice was associated with increased despair in the forced swim and anhedonia in the sucrose preference test. 9CDHRA similarly to synthetic RXR agonist, BMS649, normalized despair behaviors in Rbp1−/− but not Rxrγ−/− mice, supporting involvement of RXR signaling in anti-despair activity of these ligands. Importantly, similarly to BMS649, the 9CDHRA and its nutritional-precursor, 9-cis-13,14-dihydroretinol (vitamin A5/X alcohol), prevented development of depressive-like behaviors in mice exposed to chronic social defeat stress, revealing the beneficial role of RXRs and its endogenous ligand in stress adaptation process. These data point to the need for relevant nutritional, biochemical and pharmacological studies of this signaling pathway in human, both in physiological conditions and in pathologies of stress-related disorders.

Nitrogen Starvation-Responsive MicroRNAs Are Affected by Transgenerational Stress in Durum Wheat Seedlings

Stress events have transgenerational effects on plant growth and development. In Mediterranean regions, water-deficit and heat (WH) stress is a frequent issue that negatively affects crop yield and quality. Nitrogen (N) is an essential plant macronutrient and often a yield-limiting factor for crops. Here, the response of durum wheat seedlings to N starvation under the transgenerational effects of WH stress was investigated in two genotypes. Both genotypes showed a significant reduction in seedling height, leaf number, shoot and root weight (fresh and dry), primary root length, and chlorophyll content under N starvation stress. However, in the WH stress-tolerant genotype, the percentage reduction of most traits was lower in progeny from the stressed parents than progeny from the control parents. Small RNA sequencing identified 1534 microRNAs in different treatment groups. Differentially expressed microRNAs (DEMs) were characterized subject to N starvation, parental stress and genotype factors, with their target genes identified in silico. GO and KEGG enrichment analyses revealed the biological functions, associated with DEM-target modules in stress adaptation processes, that could contribute to the phenotypic differences observed between the two genotypes. The study provides the first evidence of the transgenerational effects of WH stress on the N starvation response in durum wheat.

Characterization of DinJ-YafQ toxin-antitoxin module in Tetragenococcus halophilus: activity, interplay, and evolution.

Tetragenococcus halophilus is a moderately halophilic lactic acid bacterium widely used in high-salt food fermentation because of its coping ability under various stress conditions. Bacterial toxin-antitoxin (TA) modules are widely distributed and play important roles in stress response, but those specific for genus Tetragenococcus have never been explored. Here, a bona fide TA module named DinJ1-YafQ1tha was characterized in T. halophilus. The toxin protein YafQ1tha acts as a ribonuclease, and its overexpression severely inhibits Escherichia coli growth. These toxic effects can be eliminated by introducing DinJ1tha, indicating that YafQ1tha activity is blocked by the formed DinJ1-YafQ1tha complex. In vivo and in vitro assays showed that DinJ1tha alone or DinJ1-YafQ1tha complex can repress the transcription of dinJ1-yafQ1tha operon by binding directly to the promoter sequence. In addition, dinJ1-yafQ1tha is involved in plasmid maintenance and stress response, and its transcriptional level is regulated by various stresses. These findings reveal the possible roles of DinJ1-YafQ1tha system in the stress adaptation processes of T. halophilus during fermentation. A single antitoxin DinJ2tha without a cognate toxin protein was also found. Its sequence shows low similarity to that of DinJ1tha, indicating that this antitoxin may have evolved from a different ancestor. Moreover, DinJ2tha can cross-interact with noncognate toxin YafQ1tha and cross-regulate with dinJ1-yafQ1tha operon. In summary, DinJ-YafQtha characterization may be helpful in investigating the key roles of TA systems in T. halophilus and serves as a foundation for further research. KEY POINTS: • dinJ1-yafQ1tha is the first functional TA module characterized in T. halophilus and upregulated significantly upon osmotic and acidic stress. • DinJ2tha can exhibit physical and transcriptional interplay with DinJ1-YafQ1tha. • dinJ2tha may be acquired from bacteria in distant affiliation and inserted into the T. halophilus genome through horizontal gene transfer.

Parenting Stress Experience and Adaptation Process of Working Moms during the COVID-19 Pandemic

Parenting Stress Experience and Adaptation Process of Working Moms during the COVID-19 Pandemic

Signatures of local adaptation to climate in natural populations of sweet chestnut (Castanea sativa Mill.) from southern Europe

• Key message Understanding the adaptive mechanisms of forest species is vital to ensure their survival in a climate change scenario. This study aimed at uncovering the relationship between genetic variability and environmental variables in natural Castanea sativa populations, unveiling how different climate scenarios drove local adaption processes using a landscape genomics approach. Our findings provide useful data for future management of this species. • Context Temperate forest species, such as chestnut (Castanea sativa Mill.), are currently threatened by increasing temperature together with disruption and reduction of precipitation due to climate change. In this context, understanding the adaptation processes of species will help to manage and ensure the conservation of forests.• Aims We studied the relationship between genetic variability and climate variables in natural populations of C. sativa using a landscape genomics approach aimed to identify local adaption processes.• Methods Using five genomic SSRs and eight functional EST-SSRs markers, 268 individuals belonging to ten different natural European chestnut populations distributed in contrasting climatic sites were genotyped. In addition, associations between allelic variation and climatic variables (environmental association analyses approach) were performed using Samβada and LFMM.• Results Results highlighted a strong inter-relationship between climate variables and evolutionary processes resulting in adaptive variation. STRUCTURE analysis based on functional markers split the populations in three separate gene pools (K = 3), mostly in agreement with the different climatic conditions existing in the studied areas. Divergent spatial patterns of genetic variation between rainy and arid areas were found. We detected a total of 202 associations with climate among 22 different alleles, 9% of which related with the outlier locus FIR059, known to be implicated in regulatory mechanisms during water stress adaptation processes.• Conclusion Landscape genomics analyses revealed a pattern of adaptive variation, where specific climatic variables influenced the frequencies distribution and fixation of several alleles, resulting in local adaptation processes of the populations in the investigated areas. Our findings underline the close inter-relationship existing between climate and genetic variability and indicate how this approach could provide valuable information for the management of forest species in a rapidly changing environment.

Whole-Genome DNA Methylation Analysis in Hydrogen Peroxide Overproducing Transgenic Tobacco Resistant to Biotic and Abiotic Stresses.

Epigenetic regulation is a key component of stress responses, acclimatization and adaptation processes in plants. DNA methylation is a stable mark plausible for the inheritance of epigenetic traits, such that it is a potential scheme for plant breeding. However, the effect of modulators of stress responses, as hydrogen peroxide (H2O2), in the methylome status has not been elucidated. A transgenic tobacco model to the CchGLP gene displayed high H2O2 endogen levels correlated with biotic and abiotic stresses resistance. The present study aimed to determine the DNA methylation status changes in the transgenic model to obtain more information about the molecular mechanism involved in resistance phenotypes. The Whole-genome bisulfite sequencing analysis revealed a minimal impact of overall levels and distribution of methylation. A total of 9432 differential methylated sites were identified in distinct genome regions, most of them in CHG context, with a trend to hypomethylation. Of these, 1117 sites corresponded to genes, from which 83 were also differentially expressed in the plants. Several genes were associated with respiration, energy, and calcium signaling. The data obtained highlighted the relevance of the H2O2 in the homeostasis of the system in stress conditions, affecting at methylation level and suggesting an association of the H2O2 in the physiological adaptation to stress functional linkages may be regulated in part by DNA methylation.

A Grounded Theory Approach on Correctional Officers' Adaptation Process of Job Stress

Purpose: The purpose of this qualitative study is to explore the adaptation process of correctional officers’ job stress. Methods: Participants collected were fourteen officers who had experienced the adaptation process of job stress. Data were collected through individual in-depth interviews until the point of theoretical saturation from May to August, 2017. Transcribed interview contents were analyzed using Corbin and Strauss’ grounded theory method. Results: A total of 98 concepts, 27 subcategories, and 10 categories were identified through the open coding. As a result of axial coding based on the paradigm model, the job stress adaptation process centering phenomenon of correctional officers was revealed as ‘repeat-mark hardening’, and the core category was extracted as ‘endurance in hardening’ consisting of a three-step process: enduring, understanding prisoner management procedures, and rebuilding. The rebuilding was considered as the key phase to escape the repeat-mark hardening and the participants utilized various strategies such as finding fun elsewhere, restoring confidence, accepting values of the prison officer in this phase. Conclusion: The results of this study suggest that the adaptation process of correctional officers’ job stress can be a process that endurance the hardening. Therefore, it is necessary to develop systematic practical education and vocational motivation programs.

Understanding metabolic adaptation by using bacterial laboratory evolution and trans-omics analysis.

Many diseases such as metabolic syndrome, cancer, inflammatory diseases, and pathological phenomena can be understood as an adaptive reconstitution of the metabolic state (metabolic adaptation). One of the effective approaches to reveal the property of metabolic networks is using model organisms such as microorganisms that are easier to experiment with than higher organisms. Using the laboratory evolution approach, we can elucidate the evolutionary dynamics in various stress environments, which provide us an understanding of the metabolic adaptation. In addition, the integration of omics data and phenotypic data enables us to clarify the genetic and phenotypic alterations during adaptation. In this review, we describe our recent studies on bacterial laboratory evolution and the omics approach to clarify the stress adaptation process. We have also obtained high-dimensional phenotypic data using our automated culture system. By combining these genomic and transcriptomic data within high-throughput phenotypic data, we can discuss the complex trans-omics network of metabolic adaptation.

Investigating the role of nitric oxide in stress adaptive process in electric foot shock stress-subjected mice

Aim The present study was designed to investigate the role of nitric oxide (NO) in the non-development of stress adaptation in high-intensity foot-shock stress (HIFS) subjected mice. Methods Mice were subjected to low-intensity shocks (LIFS i.e. 0.5 mA) or HIFS (1.5 mA) for 5 days. Stress-induced behavioral changes were assessed by actophotometer, hole board, open field and social interaction tests. Biochemically, the serum corticosterone levels were measured as a marker of stress. L-arginine (100 mg/kg and 300 mg/kg), as NO donor, and L-NAME (10 mg/kg and 30 mg/kg), as nitric oxide synthase (NOS) inhibitor, were employed as pharmacological agents. Results A single exposure of LIFS and HIFS produced behavioral and biochemical alterations. However, there was the restoration of behavioral and biochemical alterations on 5th day in response to repeated LIFS exposure suggesting the development of stress adaptation. However, no stress adaptation was observed in HIFS subjected mice. Administration of L-arginine (300 mg/kg) abolished the stress adaptive response in LIFS-subjected mice, while L-NAME (30 mg/kg) induced the development of stress adaptation in HIFS subjected mice. Conclusion It is concluded that an increase in the NO release may possibly impede the process of stress adaptation in HIFS-subjected mice.