Stress Cues Research Articles

How do persons with apraxia of speech deal with morphological stress in Spanish? A preliminary study

ABSTRACT Equal stress across adjacent syllables and extended syllable durations are amongst the most salient features of acquired Apraxia of Speech (AOS). Most studies conclude that there is a deficit in durational cue processing, whereas the other acoustic stress correlates remain relatively unimpaired. Spanish is a free-stress language in which stress patterns are contrastive, especially in verbal forms (e.g. lavo /ˈlabo/ ‘[I] wash’ vs lavó /laˈbo/ ‘[He/she] washed’). The aim of this preliminary study is to determine whether persons with AOS are able to make the intended stress pattern identifiable and, if so, to determine which acoustic cues they use to avoid the ‘equal stress’ phenomenon. The results show that, for each parameter considered (duration, intensity, fundamental frequency), apraxic participants’ productions differed from those of controls to varying degrees depending on the task. However, 91.7% of the apraxic participants’ realisations were perceived as corresponding to the intended tense and person. These results are interpreted as deriving from a motoric deficit affecting morphological stress processing by subjects with AOS combined with an idiosyncratic compensatory use of the stress cues in order to avoid ‘equal stress’.

Genome-Wide Characterization of AspATs in Populus: Gene Expression Variation and Enzyme Activities in Response to Nitrogen Perturbations

Aspartate aminotransferase (AspAT) catalyzes a reversible transamination reaction between glutamate and oxaloacetate to yield aspartate and 2-oxoglutarate, exerting a primary role in amino acid biosynthesis and homeostasis of nitrogen (N) and carbon metabolism within all cellular organisms. While progress in biochemical characterization of AspAT has been made for decades, the molecular and physiological characteristics of different members of the AspAT gene family remain poorly known particularly in forest trees. Here, extensive genome-wide survey of AspAT encoding genes was implemented in black cottonwood (Populus trichocarpa Torr. & A. Gray), a model species of woody plants. Thorough inspection of the phylogenies, gene structures, chromosomal distribution, cis-elements, conserved motifs, and subcellular targeting resulted in the identification of 10 AspAT isogenes (PtAspAT1-10) in the Populus genome. RNA-seq along with quantitative real-time polymerase chain reaction (qRT-PCR) validation revealed that PtAspATs displayed diverse patterns of tissue-specific expression. Spatiotemporal expressions of homologous AspATs in the poplar hybrid clone ‘Nanlin895’ were further evaluated, showing that gene expressions varied depending on source-sink dynamics. The impact on AspAT transcripts upon N starvation and seasonal senescence showed the upregulation of five AspAT in leaves concurrent with drastic downregulation of six or more AspATs in roots. Additionally, marked reductions of many more AspATs transcripts were observed in roots upon N excess. Accordingly, AspAT activities were significantly suppressed upon N starvation by an in-gel assay, prompting the argument that enzyme activity was a more direct indicator of the growth morphology under a N stress regime. Taken together, the expression profiling and enzyme activities upon stress cues provide a theoretical basis for unraveling the physiological significance of specific gene(s) in regulation of N acquisition and remobilization in woody plants.

Neural Correlates of Personalized Spiritual Experiences.

Across cultures and throughout history, human beings have reported a variety of spiritual experiences and the concomitant perceived sense of union that transcends one's ordinary sense of self. Nevertheless, little is known about the underlying neural mechanisms of spiritual experiences, particularly when examined across different traditions and practices. By adapting an individualized guided-imagery task, we investigated neural correlates of personally meaningful spiritual experiences as compared with stressful and neutral-relaxing experiences. We observed in the spiritual condition, as compared with the neutral-relaxing condition, reduced activity in the left inferior parietal lobule (IPL), a result that suggests the IPL may contribute importantly to perceptual processing and self-other representations during spiritual experiences. Compared with stress cues, responses to spiritual cues showed reduced activity in the medial thalamus and caudate, regions associated with sensory and emotional processing. Overall, the study introduces a novel method for investigating brain correlates of personally meaningful spiritual experiences and suggests neural mechanisms associated with broadly defined and personally experienced spirituality.

Molecular Mechanisms of Plant Regeneration.

Plants reprogram somatic cells following injury and regenerate new tissues and organs. Upon perception of inductive cues, somatic cells often dedifferentiate, proliferate, and acquire new fates to repair damaged tissues or develop new organs from wound sites. Wound stress activates transcriptional cascades to promote cell fate reprogramming and initiate new developmental programs. Wounding also modulates endogenous hormonal responses by triggering their biosynthesis and/or directional transport. Auxin and cytokinin play pivotal roles in determining cell fates in regenerating tissues and organs. Exogenous application of these plant hormones enhances regenerative responses in vitro by facilitating the activation of specific developmental programs. Many reprogramming regulators are epigenetically silenced during normal development but are activated by wound stress and/or hormonal cues.

Predation risk affects egg mortality and carry over effects in the larval stages in damselflies

Abstract The non‐consumptive predator effect may incur physiological costs that affect growth and development and ultimately survival. While studies have shown that the effect can affect development and growth in organisms with complex life cycles, we have limited knowledge on the effect in the egg and early larval stage. Here, we used a laboratory experiment to examine how the presence of chemical cues, a non‐consumptive predator effect, from an aquatic predator, perch, affected hatching success of larvae in three species of damselfly, Ischnura elegans, Coenagrion pulchellum, and Enallagma cyathigerum. In addition, we examined how exposure to predation risk in the early larval stages affected growth in the late larval stages of I. elegans. We found that the presence of chemical predator cues (1) increased egg mortality in all three species, (2) caused earlier hatching of eggs in one species, no change in a second species and a delay in egg hatching in a third species. We also found that predator cues have the potential to cause a carryover effect from early larval stages to late larval stages in terms of larval growth rate. The addition of non‐consumptive predator cues in the form of fish water caused higher algal growth than in the control experimental containers, and we suggest that this algal growth has the potential to confound predator stress cues. Our results show that the non‐consumptive predator effects affect survival and growth, and hence they have the potential to affect predator–prey dynamics in natural systems. Future studies on such effects in aquatic systems should consider confounding stressors, such as algae, fungi, oxygen, and nutrients levels, that might come with the addition of predation cues in water and thus add additional stress.

Juxtacrine regulation of cellular senescence

Cellular senescence is defined as a state of stable cell cycle exit in response to various stimuli, which include both cytotoxic stress and physiological cues. In addition to the core non-proliferative aspect, senescence is associated with diverse functionalities, which contribute to the role of senescence in a wide range of pathological and physiological processes. Such functionality is often mediated by the capability of senescent cells to communicate with their surroundings. Emerging evidence suggests that senescence is not a single entity, but a dynamic and heterogeneous collective phenotype. Understanding the diverse nature of senescence should provide insights into the complexity of tissue homeostasis and its disruption, such as in aging and tumorigenesis.

Investigation of the AQP Family in Soybean and the Promoter Activity of TIP2;6 in Heat Stress and Hormone Responses.

Aquaporins (AQPs) are one diverse family of membrane channel proteins that play crucial regulatory roles in plant stress physiology. However, the heat stress responsiveness of AQP genes in soybean remains poorly understood. In this study, 75 non-redundant AQP encoding genes were identified in soybean. Multiple sequence alignments showed that all GmAQP proteins possessed the conserved regions, which contained 6 trans-membrane domains (TM1 to TM6). Different GmAQP members consisted of distinct Asn-Pro-Ala (NPA) motifs, aromatic/arginine (ar/R) selectivity filters and Froger’s positions (FPs). Phylogenetic analyses distinguished five sub-families within these GmAQPs: 24 GmPIPs, 24 GmTIPs, 17 GmNIPs, 8 GmSIPs, and 2 GmXIPs. Promoter cis-acting elements analyses revealed that distinct number and composition of heat stress and hormone responsive elements existed in different promoter regions of GmAQPs. QRT-PCR assays demonstrated that 12 candidate GmAQPs with relatively extensive expression in various tissues or high expression levels in root or leaf exhibited different expression changes under heat stress and hormone cues (abscisic acid (ABA), l-aminocyclopropane-l-carboxylic acid (ACC), salicylic acid (SA) and methyl jasmonate (MeJA)). Furthermore, the promoter activity of one previously functionally unknown AQP gene-GmTIP2;6 was investigated in transgenic Arabidopsis plants. The beta-glucuronidase (GUS) activity driven by the promoter of GmTIP2;6 was strongly induced in the heat- and ACC-treated transgenic plants and tended to be accumulated in the hypocotyls, vascular bundles, and leaf trichomes. These results will contribute to uncovering the potential functions and molecular mechanisms of soybean GmAQPs in mediating heat stress and hormone signal responses.

Revisiting Stress "Deafness" in European Portuguese - A Behavioral and ERP Study.

European Portuguese (EP) is a language with variable stress, and the main cues for stress are duration and vowel reduction. A previous behavioral study has reported a stress “deafness” effect in EP when vowel quality cues are unavailable. The present study recorded both event-related potentials (ERPs) and behavioral data to examine the stress processing by native EP speakers in the absence of the vowel quality cues. Our behavioral result was consistent with previous research, showing that when vowel reduction is absent EP speakers demonstrated a stress “deafness” effect similar to that found in speakers of languages with fixed stress or without any lexical stress marking. In the ERP task, both the trochaic and iambic conditions yielded mismatch negativity (MMN) and late negativity, suggesting that EP speakers are able to discriminate the two stress patterns without vowel reduction at the pre-attentive stage. Moreover, the ERP and behavioral data revealed compatible results regarding the pattern of stress bias in EP. In the EPR task, the MMN and late negativity components were more negative and span over a larger temporal window in the iambic condition than in the trochaic condition, indicating a higher sensitivity for the iambic stress pattern. In the behavioral task, EP speakers responded more accurately and more quickly to the iambic stress. These results match recent developmental findings in the acquisition of stress, but speak against the dominant view in EP phonological literature which assumes penultimate stress to be the regular stress pattern. In addition, both the ERP and the behavioral data showed that EP speakers’ stress processing was influenced by their working memory (WM) capacity. The participants with high WM capacity outperformed the participants with limited WM capacity in the iambic condition. In sum, our results broaden the current knowledge on stress processing by EP speakers at both the pre-attentive and attentive levels.

Chemical recognition in the symbiotic pea crab Dissodactylus crinitichelis (Crustacea: Decapoda: Pinnotheridae): host and conspecific cues

The ability of chemical recognition is important for marine invertebrates to detect if host conditions (such as stress) are suitable for colonisation, and the presence of conspecifics can also be important for host switching. We investigated whether Dissodactylus crinitichelis can recognize the sand dollar Encope emarginata by chemical cues, and if factors such as host stress condition and presence of conspecifics may affect its chemical attraction to the host. In the host cue treatment, crabs showed no significant attraction (p = .1), although they perceived host stress conditions extensively in the host stress experiment, and mostly avoided the host (p < .01) water. In the host plus conspecifics experiment, crabs significantly responded (p < .01) to these cues. The lack of attraction to host cues suggested that the host presence is not enough to induce attraction on the crabs. Moreover, host cues might not be as stimulant as host stress cues, which might signal that hosts are not suitable, or that these cues might infer predation risk to the symbionts. Finally, the presence of conspecifics on the hosts may be a reliable way to encounter suitable hosts. It may also increase the chance of finding mating partners and thus mating opportunities; therefore, the higher preference for occupied hosts is important for the mating system of the crabs. The results reject the hypothesis that the symbiont-host relationship is based exclusively on host chemical cues, suggesting that intrinsic triggers, such as host condition and conspecific presence can induce host recognition and influence crab behaviour and mating success.

Endothelial Cell Mechanotransduction in the Dynamic Vascular Environment.

The vascular endothelial cells (ECs) that line the inner layer of blood vessels are responsible for maintaining vascular homeostasis under physiological conditions. In the presence of disease or injury, ECs can become dysfunctional and contribute to a progressive decline in vascular health. ECs are constantly exposed to a variety of dynamic mechanical stimuli, including hemodynamic shear stress, pulsatile stretch, and passive signaling cues derived from the extracellular matrix. This review describes the molecular mechanisms by which ECs perceive and interpret these mechanical signals. The translational applications of mechanosensing are then discussed in the context of endothelial-to-mesenchymal transition and engineering of vascular grafts.

Insights into regulatory roles of MAPK-cascaded pathways in multiple stress responses and life cycles of insect and nematode mycopathogens.

Fungal entomopathogenicity may have evolved at least 200 million years later than carnivorism of nematophagous fungi on Earth. This mini-review focuses on the composition and regulatory roles of mitogen-activated protein kinase (MAPK) cascades, which act as stress-responsive signaling pathways. Unveiled by genomic comparison, three MAPK cascades of these mycopathogens consist of singular MAPKs (Fus3/Hog1/Slt2), MAPK kinases (Ste7/Pbs2/Mkk1), and MAPK kinase kinases (Ste11/Ssk2/Bck1). All cascaded components characterized in fungal entomopathogens play conserved and special roles in regulating multiple stress responses and phenotypes associated with biological control potential. Fus3-cascaded components are indispensable for fungal growth on oligotrophic substrata and virulence, and mediate cell tolerance to Na+/K+ toxicity, which is often misinterpreted as hyperosmotic effect but readily clarified by transcriptional changes of Na+/K+ ATPase genes and/or cell responses to osmotic polyols. Hog1-cascaded components regulate osmotolerance positively and phenylpyrrole-type fungicide resistance negatively, and also play differential roles in cell growth, conidiation, virulence, and responses to other stress cues. Ste11 has no stress-responsive role in the Beauveria Hog1 cascade despite an essential role in branched yeast Hog1 cascade. Slt2-cascaded components are required for mediation of cell wall integrity and repair of cell wall damage. A crosstalk between Hog1 and Slt2 cascades ensures fungal osmotolerance inside or outside insect. In nematode-trapping fungi, Slt2 is indispensable for cell wall integrity, conidiation, and mycelial trap formation, suggesting that the Slt2 cascade could have evolved along a distinct trajectory required for fungal carnivorism and dispersal/survival in nematode habitats. Altogether, the MAPK cascades are major parts of signaling network that regulate fungal adaptation to insects and nematodes and their habitats.

Trehalose: A Key Organic Osmolyte Effectively Involved in Plant Abiotic Stress Tolerance

Trehalose is a natural non-reducing sugar that is found in the vast majority of organisms such as bacteria, yeasts, invertebrates and even in plants. Regarding its features, it is considered as a unique compound. It plays a key role as a carbon source in lower organisms and as an osmoprotectant or a stabilizing molecule in higher animals and plants. Although in plants it is present in a minor quantity, its levels rise upon exposure to abiotic stresses. Trehalose is believed to play a protective role against different abiotic stressful cues such as temperature extremes, salinity, desiccation. Moreover, it regulates water use efficiency and stomatal movement in most plants. Detectable endogenous trehalose levels are vital for sustaining growth under stressful cues. Exogenously applied trehalose in low amounts mitigates physiological and biochemical disorders induced by various abiotic stresses, delays leaf abscission and stimulates flowering in crops. External application of trehalose also up-regulates the stress responsive genes in plants exposed to environmental cues. The genetically modified plants with trehalose biosynthesis genes exhibit improved tolerance against stressful conditions. An increased level of trehalose has been observed in transgenic plants over-expressing genes of microbial trehalose biosynthesis. However, these transgenic plants display enhanced tolerance to heat, cold, salinity, and drought tolerance. Due to multiple bio-functions of this sugar, it has gained considerable ground in various fields. However, exogenous use of this bio-safe sugar would only be possible under field conditions upon adopting strategies of low-cost production of trehalose. In short, trehalose is a unique chemical that preserves vitality of plant life under harsh ecological conditions. Certainly, the new findings of this disaccharide will revolutionize a wide array of new avenues.

Sex Differences in Subjective and Behavioral Responses to Stressful and Smoking Cues Presented in the Natural Environment of Smokers.

Some evidence suggests that female smokers may show more context-dependent smoking and that males may show more stereotyped smoking (regardless of stress or cue exposure). The goal of this study was to characterize sex differences in response to stressful and smoking cues ecologically presented in daily life and variability in day-to-day smoking behavior. Adult smokers (N = 177) provided ratings of mood and cigarette craving before and after stress and smoking cues were presented four times daily for 14 days via a mobile device. Linear mixed models tested whether (1) female smokers exhibited greater reactivity to stressful cues than male smokers; (2) pre-cue negative affect increased reactivity to smoking cues more in female smokers than male smokers; (3) across both sexes, greater reactivity to stressful and smoking cues correlated with greater quantity of smoking within a day; and (4) female smokers exhibited greater variability in cigarettes per day (CPD) relative to males. Relative to male smokers, female smokers reported greater negative affect, stress, and craving in response to stressful cues, but not smoking cues, after accounting for time since last cigarette and pre-cue responding. No sex differences in CPD or variability in CPD were detected. Days with higher subjective reactivity to cues were not associated with increased smoking, in either males or females. Sex differences were observed in response to stress but not smoking cues in the natural environment of regular cigarette smokers. Further research is necessary to evaluate whether stress reactivity in female smokers is associated with reduced latency to smoke following stress exposure in daily life. This study provides naturalistic evidence that female smokers may not be more reactive to smoking cues than males, but experience heightened stress and craving following stress exposure. There was no evidence to support the hypothesis that amount smoked per day varied more for females, relative to males, as a result of more context-driven smoking for females.

Childhood trauma moderates inhibitory control and anterior cingulate cortex activation during stress

ObjectiveThe anterior cingulate cortex (ACC) is critical for both stress and inhibitory control processes and has been implicated in childhood trauma. This prospective study tested the hypothesis that early trauma moderates the association between inhibitory control during late childhood and ACC stress reactivity during adolescence. Method: Sixty-four adolescents were stratified into higher- or lower-childhood-trauma groups. Inhibitory control was indicated by fewer errors on a Stroop Color-Word task. Personalized stress cues during functional magnetic resonance imaging assessed neural correlates of stress in adolescents. Results: Using a priori-defined anterior (rCZa) and posterior rostral cingulate zones of the ACC, associated with Stroop Color-Word task performance in prior meta-analyses, Stroop errors correlated inversely with activation in the rCZa during stress-cue exposure (r = −.23, p = .04). Childhood trauma moderated the association between Stroop errors and rCZa stress reactivity (interaction = −1.26, p = .02, 95%CI = −2.33,-0.20), where Stroop errors were inversely associated with brain activation among those with higher childhood trauma (simple slopes = −.83, p = .007, 95%CI = −1.40,-0.25). Low stress-related rCZa activation inversely (R2 = 0.19, b = −0.43, p = .001, 95%CI = −4.11,-1.06) and Stroop errors directly (R2 = 0.09, b = 0.27, p = .048, 95%CI = 0.02, 5.8) associated with baseline subjective anxiety while controlling for childhood trauma. Conclusions: This is the first study to demonstrate a moderating role of childhood trauma on the relationship between inhibitory control and stress-related ACC activation. Childhood trauma may portend neurodevelopmental changes that impede recruitment of control-associated ACC-functioning during distress, which may relate to dysregulation of stress-induced affective responses. Further work is needed to elucidate relationships between childhood trauma and addictive behaviors precipitated by stress.

The acquisition of English stress by Kazakh-Russian bilinguals: The role of dominant language

This study systematically investigates the cross-linguistic influence of the acquisition of English lexical stress by Kazakh-Russian bilinguals. Experiment 1 examined the Kazakh accent/stress pattern. Even though there is an argument about Kazakh stress, we used near minimal pairs in Kazakh such as balaDAR “children” vs. balaDAY “like a child, childish.” By measuring duration, intensity, and pitch on 20 Kazakh-Russian bilinguals with strong Kazakh language level, we compared the stressed syllable versus unstressed syllables in the near minimal pairs and found duration as a stronger cue for the stress/accent in the syllables. In experiment 2 we investigated the roles of Russian as the dominant language in cross-linguistic influences. We used ten minimal pairs in Russian produced by 20 Russian bilinguals who claimed their native language is Russian. The results showed Kazakh-Russian bilinguals produced Russian stress using duration. Experiment 3 focuses on the acquisition of stress pattern in English by Kazakh-Russian bilinguals. We recruited 40 participants with (IELTS= 7.0) producing 10 English minimal pairs in three conditions. We found that duration and intensity are stronger cues than F0. None of the group used F0 as a stress cue in English lexical stress. The result will be discussed regarding dominant Russian language.

Craving, cortisol and behavioral alcohol motivation responses to stress and alcohol cue contexts and discrete cues in binge and non-binge drinkers.

Alcohol use disorders are associated with high craving and disruption of stress biology, but their role in behavioral alcohol motivation is less clear. We examined the effects of craving and cortisol responses on behavioral alcohol motivation to stress, alcohol cue and neutral-relaxing context cues, in addition to discrete alcohol cues, in demographically matched binge/heavy (BH) and moderate (MD) social drinkers. Subjects participated in a 3-day laboratory experiment of provocation by three personalized guided imagery contexts and discrete alcohol cues followed by the 'alcohol taste test' (ATT) to assess behavioral motivation, as measured by ATT intake. Post-ATT alcohol effects on craving and cortisol responses were also examined. Results indicate BH consumed significantly more alcohol than MD in the ATT. Stress and alcohol cue contexts, relative to neutral, led to significantly greater ATT intake across both groups, which also correlated positively with self-reported alcohol use in past 30days. Stress and alcohol context and discrete alcohol cues each significantly increased alcohol craving, more so in the BH than MD, and significantly predicted greater ATT intake in BH only. The BH showed significantly lower cortisol responses than MD overall and blunted cortisol responses to cues predicted significantly greater ATT intake in the stress condition for BH and in the alcohol cue condition for MD. Higher ATT intake predicted greater cortisol response and higher craving post-ATT, and these effects were moderated by group status. In sum, findings suggest a role for sensitized context-induced craving and blunted cortisol responses in increased behavioral motivation for alcohol.

Reprogramming the Stem Cell Behavior by Shear Stress and Electric Field Stimulation: Lab-on-a-Chip Based Biomicrofluidics in Regenerative Medicine

The biophysical cues of endogenous origin, i.e., shear stress and electric field, are known to significantly modulate cell functionality, in vitro. While this has been relatively well investigated in conventional petri dish culture, it is important to validate such important phenomenon in physiologically simulated cellular microenvironment. In this perspective, this review critically discusses the importance of lab-on-a-chip (LOC)-based microfluidic devices to probe into this aspect to develop an insight towards the application in regenerative medicine. While reviewing several literature reports, an emphasis has been placed to unravel the intriguing aspects of shear and electric field modulated differentiation of stem cells in the biomicrofluidics devices. The potential application focusing the stem cell culture was emphasized in this article as the stem cells are the foundation of tissue regeneration. Several challenges in tissue regeneration and introduction of personalized medicine could be addressed through microfluidic technology. Culturing of organ-specific multiple cell types within lab-on-a-chip and biophysical stimulation mediated activations of intracellular signal transduction under gradient shear/electric field are highlighted in this review. Conceptually, regenerative medicine is considered as an emerging approach for treating traumatized, malfunctional anatomical parts of the patients with stem cells to establish normal functionality of the tissue. The regenerated tissue should preferably be the patients’ autologous tissue, grown under artificially created in vivo physiological environment. Biomicrofluidic-based lab-on-a-chip technology enables to perform in vitro cell/tissue engineering under endogenous cues, like shear and electric field. Therefore, this review discusses two aspects of regenerative medicine in terms of autologous transplantation of cells/tissues to improvise personalized regenerative medicine and to recreate an organ-specific tissue under the influence of biophysical stimulation in an attempt to improve the physiological functionality.

Roles of Three HSF Domain-Containing Proteins in Mediating Heat-Shock Protein Genes and Sustaining Asexual Cycle, Stress Tolerance, and Virulence in Beauveria bassiana.

Heat-shock transcription factors (HSFs) with a HSF domain are regulators of fungal heat-shock protein (HSP) genes and many others vectoring heat-shock elements, to which the domain binds in response to heat shock and other stress cues. The fungal insect pathogen Beauveria bassiana harbors three HSF domain-containing orthologous to Hsf1, Sfl1, and Skn7 in many fungi. Here, we show that the three proteins are interrelated at transcription level, play overlapping or opposite roles in activating different families of 28 HSP genes and mediate differential expression of some genes required for asexual developmental and intracellular Na+ homeostasis. Expression levels of skn7 and sfl1 largely increased in Δhsf1, which is evidently lethal in some other fungi. Hsf1 was distinct from Sfl1 and Skn7 in activating most HSP genes under normal and heat-shocked conditions. Sfl1 and Skn7 played overlapping roles in activating more than half of the HSP genes under heat shock. Each protein also activated a few HSP genes not targeted by two others under certain conditions. Deletion of sfl1 resulted in most severe growth defects on rich medium and several minimal media at optimal 25°C while such growth defects were less severe in Δhsf1 and minor in Δskn7. Conidiation level was lowered by 76% in Δskn7, 62% in Δsfl1, and 39% in Δhsf1. These deletion mutants also showed differential changes in cell wall integrity, antioxidant activity, virulence and cellular tolerance to osmotic salt, heat shock, and UV-B irradiation. These results provide a global insight into vital roles of Hsf1, Sfl1, and Skn7 in B. bassiana adaptation to environment and host.

Chromatin-based mechanisms of temperature memory in plants.

For successful growth and development, plants constantly have to gauge their environment. Plants are capable to monitor their current environmental conditions, and they are also able to integrate environmental conditions over time and store the information induced by the cues. In a developmental context, such an environmental memory is used to align developmental transitions with favourable environmental conditions. One temperature-related example of this is the transition to flowering after experiencing winter conditions, that is, vernalization. In the context of adaptation to stress, such an environmental memory is used to improve stress adaptation even when the stress cues are intermittent. A somatic stress memory has now been described for various stresses, including extreme temperatures, drought, and pathogen infection. At the molecular level, such a memory of the environment is often mediated by epigenetic and chromatin modifications. Histone modifications in particular play an important role. In this review, we will discuss and compare different types of temperature memory and the histone modifications, as well as the reader, writer, and eraser proteins involved.

Impact of exogenously applied tocopherol on some key physio-biochemical and yield attributes in mungbean [Vigna radiata (L.) Wilczek] under limited irrigation regimes

The lipophilic vitamin E, α-Tocopherol (α-Toc), has been considered as a potent cellular antioxidant naturally occurring in biological membranes. It plays a number of key metabolic roles in plants exposed to various stressful cues. A field experimental was conducted on mungbean [Vigna radiata (L.) Wilczek] under varying water-limited regimes and the plants were sprayed with four levels of α-Toc (0, 100, 200, and 300 mg L−1) at the vegetative stage of plant growth. The results showed that limited field irrigation regimes (desiccated conditions) caused a marked reduction in growth parameters (shoot and root fresh and dry weights; shoot and root lengths), photosynthetic pigments (chlorophyll a and b), total soluble proteins (TSP) and yield attributes (number of pods, seeds per plant, weight of ripened pods and 100-seeds weight), while, in contrast, water deficiency induced an increase in phenolics, proline, glycine betaine (GB), hydrogen peroxide (H2O2), malondialdehyde (MDA), reducing and non-reducing sugars, total free amino acids, endogenous tocopherol levels, and activities of antioxidant enzymes including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). However, the foliar spray of α-Toc significantly improved shoot and root fresh and dry weights, shoot and root lengths, chlorophyll a and b contents, phenolics, proline, GB, reducing and non-reducing sugars, TSP, total free amino acids, endogenous tocopherol level, and activities of antioxidant enzymes (SOD, POD, and CAT), as well as yield parameters. On the other hand, it significantly decreased the MDA and H2O2 levels. Of all varying levels of α-Toc used, 100 mg L−1 was most effective in causing enhanced accumulation of ascorbic acid (AsA), MDA, and cellular tocopherols particularly in cv. Cyclone 7008, while proline and catalase in cv. Cyclone 8009. Of both cultivars, Cyclone 7008 was superior to the other cultivar in proline, TSP, SOD, and POD enzymes, but cv. Cyclone 8009 being superior in shoot fresh weights, root fresh weight, shoot and root lengths, chlorophyll a and b, phenolics, H2O2, AsA, MDA, CAT, number of pods, seeds, weight of ripened pods, and weight of 100 seeds under dry land conditions. Overall, exogenously applied tocopherol improved yield and myriad of key physio-biochemical attribute in mungbean.