Higher Stress Response Research Articles

Exploring the Biological and Molecular Characteristics of Resistance to Fludioxonil in Sclerotinia sclerotiorum From Soybean in China.

Sclerotinia sclerotiorum is one of the most damaging and economically important necrotrophic plant pathogens, infecting more than 400 plant species globally. Although the phenylpyrrole fungicide fludioxonil has high activity against S. sclerotiorum, reports indicate that there is also substantial potential for the development of fungicide resistance. However, the current study investigating five fludioxonil-resistant laboratory mutants found a significant fitness cost associated with fludioxonil resistance resulting in significantly (P < 0.05) reduced mycelial growth and sclerotia formation on potato dextrose agar as well as significantly (P < 0.05) lower pathogenicity on detached tomato leaves, with one mutant, LK-1R, completely losing the capacity to cause infection. In addition, all of the fludioxonil-resistant mutants had significantly (P < 0.05) increased sensitivity to osmotic stress (0.5 M of potassium chloride and 1.0 M of glucose), which is consistent with the proposed fludioxonil target sites within the high osmolarity glycerol stress response mitogen-activated protein kinase (HOG1-MAPK) signaling transduction pathway. Sequence analysis of six genes from this two-component pathway, including SsHk, SsYpd, SsSk1, SsSk2, SsPbs, and SsHog, revealed several mutations that may be associated with fludioxonil resistance. For example, six separate point mutations were found in SsHk that led to changes in the predicted amino acid sequence, including A136G, F249V, G353A, E560K, M610K, and K727R. Similarly, SsPbs had three mutations (D34G, S46L, and L337E), SsSk1 and SsYpd had two (S53G and A795V for SsSk1, and E67G and Y141H for SsYpd), and SsHog and SsSk2 had one each (V220A and S763P, respectively). To our knowledge, these constitute the first reports of amino acid changes in proteins of the HOG1-MAPK pathway being associated with fludioxonil resistance in S. sclerotiorum. This study also showed a positive cross-resistance between fludioxonil and dimethachlone and procymidone, but none with tebuconazole or carbendazim, indicating that the inclusion of tebuconazole within an integrated pest management program could reduce the risk of fludioxonil resistance developing in field populations of S. sclerotiorum and ensure the sustainable production of soybeans in China into the future.

Physiological and transcriptomic analyses characterized high temperature stress response mechanisms in Sorbus pohuashanensis

Sorbus pohuashanensis (Hance) Hedl. is a Chinese native alpine tree species, but the problem of introducing S. pohuashanensis to low altitude areas has not been solved. In this study, we aimed to explore the molecular regulatory network of S. pohuashanensis in response to high-temperature stress using RNA-Sequencing technology and physiological and biochemical determination. Based on transcriptomic data, we obtained 1221 genes (752 up-regulated and 469 down-regulated) that were differentially expressed during 8 h 43℃ treatment and candidate genes were related to calcium signaling pathway, plant hormone signal transduction, heat shock factors, chaperones, ubiquitin mediated proteolysis, cell wall modification, ROS scavenging enzymes, detoxification and energy metabolism. The analysis of high temperature response at the physiological level and biochemical level were performed. The chlorophyll fluorescence parameters of leaf cells decreased, the content of osmotic regulators increased, and the activity of ROS scavenging enzymes decreased. The molecular regulatory network of S. pohuashanensis in response to high-temperature stress was preliminarily revealed in this study, which provides fundamental information improving introducing methods and discovering heat-tolerant genes involved in high-temperature stress in this species and provides a reference for other plants of the genus Sorbus.

Evolution of psychosocial burden and psychiatric symptoms in patients with psychiatric disorders during the Covid-19 pandemic

The Covid-19 pandemic highly impacts mental health worldwide. Patients with psychiatric disorders are a vulnerable risk population for worsening of their condition and relapse of symptoms. This study investigates the pandemic-related course of psychosocial burden in patients with pre-existing mental disorders. With the newly developed Goettingen psychosocial Burden and Symptom Inventory (Goe-BSI) psychosocial burden has been traced retrospectively (1) before the pandemic (beginning of 2020), (2) at its beginning under maximum lockdown conditions (March 2020), and (3) for the current state after maximum lockdown conditions (April/May 2020). The Goe-BSI also integrates the Adjustment Disorder New Module (ADNM-20), assesses general psychiatric symptoms, and resilience. A total of 213 patients covering all major psychiatric disorders (ICD-10 F0-F9) were interviewed once in the time range from April, 24th until May 11th, 2020. Across all diagnoses patients exhibited a distinct pattern with an initial rise followed by a decline of psychosocial burden (p < 0.001, partial η2 = 0.09; Bonferroni-corrected pairwise comparisons between all three time-points: p < 0.05 to 0.001). Female gender and high ADNM-20 scores were identified as risk factors for higher levels and an unfavorable course of psychosocial burden over time. Most psychiatric symptoms remained unchanged. Trajectories of psychosocial burden vary in parallel to local lockdown restrictions and seem to reflect an adaptive stress response. For female patients with pre-existing mental disorders and patients with high-stress responses, timely and specific treatment should be scheduled. With the continuation of the pandemic, monitoring of long-term effects is of major importance, especially when long incubation times for the development of mental health issues are considered.

Genome-wide identification and characterization of PIF genes and their response to high temperature stress in potato

<p id="C3">Phytochrome interacting factors (PIFs) belong to the basic helix-loop-helix (bHLH) transcription factor family, which integrates external environmental signals such as light and temperature with plant endogenous signal pathways, and then form a complex signal transduction network to precisely regulate the growth and development of plants. Up to now, there are few studies of PIF family genes in potato. Identification and analysis of StPIF family members will help to further improve the yield and quality of potatoes. In this study, BlastP analysis was performed in the potato genome database using <italic>Arabidopsis</italic> PIFs family member protein sequences as source sequences and seven StPIFs family members were identified. Systemic evolution, chromosome distribution, replication events, protein physicochemical properties, gene structure, motif prediction, promoter cis-acting elements, gene expression pattern, and the response to high temperature stress were also conducted. These results showed that all members of the StPIFs gene family contain Motif 1 (bHLH domain) and Motif 2 (APB domain); multiple cis-regulatory elements involved in light response, hormones, drought, low temperature, and circadian rhythm as well as defense and stress response regulatory elements were predicted in the promoter regions of the <italic>StPIF</italic> genes. Results of gene expression patterns and high temperature stress response at budding stage revealed that StPIFs family members had obvious tissue expression specificity, indicating their functional differentiation, and most <italic>StPIFs</italic> members had obvious responses to biotic stress and abiotic stresses including high temperature. In conclusion, these foundlings greatly enriched the understanding of the members of the StPIF family, and laid a theoretical foundation for further exploring the functions of <italic>StPIF</italic>s genes in responses to biotic stress and abiotic stress during potato growth period including high temperature at tuber stage.

Differentially Expressed Gene Patterns in Ascarid-Infected Chickens of Higher- or Lower-Performing Genotypes.

Simple SummaryNematode infections may increase mortality and welfare problems in laying hens. The two ascarid worms, Ascaridia galli and Heterakis gallinarum, are highly prevalent in laying hens kept in non-cage housing systems worldwide. The ability of a host to expel pathogens is a component of resistance to diseases. The molecular basis of differences between different host animals in their efficiency to expel worms is, however, not well understood. Therefore, we performed a detailed analysis of differentially expressed genes (DEGs) in two chicken genotypes (Lohmann Brown Plus (LB), Lohmann Dual (LD)), each with a lower or higher infection intensity level of A. galli and H. gallinarum. Our data showed significant upregulation of Guanylate Binding Protein 7 (GBP7) in LD hens. Gene ontology analysis revealed higher transcriptome activity related to “response to external stimulus” in LB hens, implying a higher stress response in this genotype. In contrast, LD hens showed higher transcriptomic expression of genes associated with a higher tolerance to infections.Here, we describe the first transcriptomic investigation of the peripheral blood of chickens exposed to Ascaridia galli and Heterakis gallinarum infections. We investigated differentially expressed gene (DEG) patterns in two chicken genotypes with either a higher (Lohmann Brown Plus, LB) or lower (Lohmann Dual, LD) laying performance level. The hens were experimentally coinfected with A. galli and H. gallinarum, and their worm burdens and infection parameters were determined six weeks post infection. Based on most representative infection parameters, the hens were clustered into lower- and higher-infection intensity classes. We identified a total of 78 DEGs contributing to infection-related phenotypic variation in the two genotypes. Our data showed significant upregulation of Guanylate Binding Protein 7 (GBP7) in LD hens, making it a promising candidate for tolerance to ascarid infections in chickens. Gene ontology analysis revealed higher transcriptome activity related to biological processes such as “response to external stimulus” in LB hens, implying a higher stress response in this genotype. In contrast, LD hens showed higher transcriptomic expression of genes related to ontology classes that are possibly associated with a higher tolerance to infections. These findings may help explain why lower-performing genotypes (i.e., LD) are less sensitive to infections in terms of maintaining their performance.

한국토종닭의 품종, 산란 연령 및 종란의 보관 기간이 병아리의 강건성에 미치는 영향

We investigated the effects of breed, laying age, and egg storage period on the vitality of chicks using the Hwanggalsaek Jaeraejong, Korean Rhode Island Red, and Korean White Leghorn chicken breeds. Their eggs were collected during the early laying period (27~29 weeks) and late laying period (50~52 weeks) and were stored for 3 days, 7 days and 14 days. After the eggs hatched, the hatching time, production performance, and organ weight of chicks were investigated. <i>IL-6</i> gene expression level and relative length of telomeres were analyzed to determine the physiological activity of the chicks. <i>HSP</i> gene expression level and heterophil to lymphocytes ratio were also analyzed to examine the degree of stress response in the chicks. The results showed that breed and laying age influenced the vitality of chicks, but the egg storage period did not. Korean Leghorn chicks were considered the weakest breed in terms of vitality owing to their low survival rate, small heart size, low physiological activity, and high stress response level. Although the survival rate of chicks produced in the early laying period was low, their high physiological activity and low stress response indicated that they had a high vitality than the chicks produced in the late laying period. In conclusion, to obtain chicks with high vitality, it would be desirable to select a high vitality breed and avoid the use of chicks produced in the late laying period.

Weaning Induces Stress-Dependent DNA Methylation and Transcriptional Changes in Piglet PBMCs.

Changes to the epigenome, including those to DNA methylation, have been proposed as mechanisms by which stress can induce long-term physiological changes in livestock species. Pig weaning is associated with dietary and social stress, both of which elicit an immune response and changes to the hypothalamic–pituitary–adrenal (HPA) axis. While differential methylation following stress has been assessed in model organisms, it remains poorly understood how the pig methylome is altered by stressors in production settings. We quantified changes in CpG methylation and transcript abundance in piglet peripheral blood mononuclear cells (PBMCs) following weaning and also assessed differential patterns in pigs exhibiting high and low stress response as measured by cortisol concentration and lesion scores. Blood was collected from nine gilt piglets 24 h before and after weaning, and whole-genome bisulfite sequencing (WGBS) and RNA-sequencing were performed on six and nine animals, respectively, at both time points. We identified 2,674 differentially methylated regions (DMRs) that were enriched within promoters of genes associated with lymphocyte stimulation and transcriptional regulation. Stress groups displayed unique differential methylation and expression patterns associated with activation and suppression of T cell immunity in low and high stress animals, respectively. Differential methylation was strongly associated with differential expression; specifically, upregulated genes were enriched among hypomethylated genes. We observed post-weaning hypermethylation of the glucocorticoid receptor (NR3C1) promoter and a significant decrease in NR3C1 expression (n = 9, p = 6.1 × 10–3). Our results indicate that weaning-associated stress elicits genome-wide methylation changes associated with differential gene expression, reduced T cell activation, and an altered HPA axis response.

The conserved transmembrane protein TMEM-39 coordinates with COPII to promote collagen secretion and regulate ER stress response.

Dysregulation of collagen production and secretion contributes to aging and tissue fibrosis of major organs. How procollagen proteins in the endoplasmic reticulum (ER) route as specialized cargos for secretion remains to be fully elucidated. Here, we report that TMEM39, an ER-localized transmembrane protein, regulates production and secretory cargo trafficking of procollagen. We identify the C. elegans ortholog TMEM-39 from an unbiased RNAi screen and show that deficiency of tmem-39 leads to striking defects in cuticle collagen production and constitutively high ER stress response. RNAi knockdown of the tmem-39 ortholog in Drosophila causes similar defects in collagen secretion from fat body cells. The cytosolic domain of human TMEM39A binds to Sec23A, a vesicle coat protein that drives collagen secretion and vesicular trafficking. TMEM-39 regulation of collagen secretion is independent of ER stress response and autophagy. We propose that the roles of TMEM-39 in collagen secretion and ER homeostasis are likely evolutionarily conserved.

Transcriptome analysis of salt stress responsiveness in the seedlings of wild and cultivated Ricinus communis L

Soil salinity is one of the major environmental factors, influencing agricultural productivity of crops. As a non-edible and ideal oilseed crop, castor (Ricinus communis L.) has great industrial value in biofuel, but molecular mechanisms of salt stress regulation are still unknown. In this study, the differentially expressed genes (DEGs) for differential salt tolerance in two castor cultivar (wild castor : Y, cultivated castor ‘Tongbi 5’: Z) were identified. 12 libraries were sampled for Illumina high-throughput sequencing to consider 132,426 nonredundant unigenes and 31,221 gene loci. Multiple phytohormones and transcription factors (TFs) were correlated with salt-tolerance and differently enriched in these two genotypes. The type 2C protein phosphatases (PP2C) homologs were all upregulated under salt stress. Importantly, IAA (1), DELLA (1) and Jasmonate zim domain (JAZ) (1) were also identified and found to be differentially expressed. Based on the co-expressed module by regulatory networks and heatmap analysis, ERF/AP2, WRKY and bHLH families were prominently participate in high salt stress response of wild and cultivated castor. Finally, these results highlight that the hub DEGs and families were more accumulated in cultivated castor than those in wild castor, providing novel insights into the salinity adaptive mechanisms and genetic improvement in castor.

Social Support Effects on Neural Stress and Alcohol Reward Responses.

Social support (SS), or having people to depend on during times of stress, may offer an emotional and neurological buffer to problem drinking. Specifically, SS may modulate reward and stress-related brain responses to mitigate perceptions of alcohol reward and stress. There is limited evidence, however, on this topic and specifically on brain networks that may modulate SS effects on stress and alcohol reward. Here we present a review of the current literature on this topic as well as data from a large community sample of 115 social drinkers. Findings from a novel fMRI task viewing alcohol cue, stress, and neutral images, in separate blocks, while providing ratings on subjective feelings of alcohol craving, stress, and arousal are included. Lower SS significantly predicted greater alcohol craving during alcohol cue and stress conditions, higher baseline levels of stress, and greater arousal in the alcohol cue, relative to neutral condition. Remarkably, individuals with low SS showed greater reward activation (ventral medial prefrontal cortex (VmPFC) and ventral striatum) during alcohol cue exposure, while those with high SS showed no such activation (p<0.001, family wise error corrected at 0.05). Furthermore, individuals with lower SS showed greater stress circuit (VmPFC, dorsal striatum, and periaqueductal gray) activation not observed in the high SS groups. Both groups showed increased amygdala activation under stress condition. The findings support the notion that SS is a powerful modulator of stress response and reward motivation. High SS buffers neural and subjective stress responses, while low SS potentiates greater reward seeking with higher alcohol craving and greater brain activation during alcohol cue exposure. Previous research and current results suggest the need to further explore the role of SS in those at risk of developing alcohol use disorder and assess novel prevention strategies to boost SS in at-risk drinkers.

Statement of Retraction

This article refers to:RETRACTED ARTICLE: GLP-1 receptor agonist lixisenatide protects against high free fatty acids-induced oxidative stress and inflammatory response

Insights from comparative proteomic analysis into degradation of phenanthrene and salt tolerance by the halophilic Martelella strain AD-3

A halophilic PAHs-degrading strain, Martelella AD-3, was previously isolated from highly saline petroleum-contaminated soil. In this study, label-free proteomics were performed to identify differentially expressed proteins (DEPs) under Group P (phenanthrene +5% salinity) and Group G (glycerol +1% salinity), which would help to reveal the mechanism of phenanthrene degradation and salt tolerance. A total of 307 up-regulated DEPs were found in Group P, including 17 phenanthrene degradation proteins. Among these phenanthrene-degrading proteins, the ferredoxin of aromatic ring-hydroxylating dioxygenase (RHD) was up-regulated by 110-fold and gentisate 1,2-dioxygenases (GDOs) were only expressed in Group P. Besides, we also found nine high salt stress response proteins, including ectoine synthase and transport protein of compatible (osmoprotectant) solutes, were differentially up-regulated. These results indicate that strain AD-3 mainly relied on RHD and dihydrodiol dehydrogenase to degrade phenanthrene, and accumulated compatible solutes for resistance to salt stress. This study provides strong theoretical guidance for understanding the degradation of phenanthrene by strain AD-3 in high salt environments.

Plasticity of the human IgM repertoire in response to long-term spaceflight.

Immune dysregulation is among the main adverse outcomes of spaceflight. Despite the crucial role of the antibody repertoire in host protection, the effects of spaceflight on the human antibody repertoire are unknown. Consequently, using high-throughput sequencing, we examined the IgM repertoire of five cosmonauts 25days before launch, after 64±11 and 129±20days spent on the International Space Station (ISS), and at 1, 7, and 30days after landing. This is the first study of this kind in humans. Our data revealed that the IgM repertoire of the cosmonauts was different from that of control subjects (n=4) prior to launch and that two out the five analyzed cosmonauts presented significant changes in their IgM repertoire during the mission. These modifications persisted up to 30days after landing, likely affected the specificities of IgM binding sites, correlated with changes in the V(D)J recombination process responsible for creating antibody genes, and coincided with a higher stress response. These data confirm that the immune system of approximately half of the astronauts who spent 6months on the ISS is sensitive to spaceflight conditions, and reveal individual responses indicating that personalized approaches should be implemented during future deep-space exploration missions that will be of unprecedented durations.

High temperature stress response is not sexually dimorphic at the whole-body level and is dependent on androgens to induce sex reversal

The understanding of the molecular and endocrine mechanisms behind environmentally-induced sex reversal in fish is of great importance in the context of predicting the potential effects of climate change, especially increasing temperature. Here, we demonstrate the global effects of high temperature on genome-wide transcription in medaka (Oryzias latipes) during early development. Interestingly, data analysis did not show sexual dimorphic changes, demonstrating that thermal stress is not dependent on genotypic sex. Additionally, our results revealed significant changes in several pathways under high temperature, such as stress response from brain, steroid biosynthesis, epigenetic mechanisms, and thyroid hormone biosynthesis, among others. These microarray data raised the question of what the exact molecular and hormonal mechanisms of action are for female-to-male sex reversal under high temperatures in fish. Complementary gene expression analysis revealed that androgen-related genes increase in females (XX) experiencing high water temperature. To test the involvement of androgens in thermal-induced sex reversal, an androgen antagonist was used to treat XX medaka under a high-temperature setup. Data clearly demonstrated failure of female-to-male sex reversal when androgen action is inhibited, corroborating the importance of androgens in environmentally-induced sex reversal.

Blood Clot Phenotyping by Rheometry: Platelets and Fibrinogen Chemistry Affect Stress-Softening and -Stiffening at Large Oscillation Amplitude.

(1) Background: Together with treatment protocols, viscoelastic tests are widely used for patient care. Measuring at broader ranges of deformation than currently done will add information on a clot’s mechanical phenotype because fibrin networks follow different stretching regimes, and blood flow compels clots into a dynamic non-linear response. (2) Methods: To characterize the influence of platelets on the network level, a stress amplitude sweep test (LAOStress) was applied to clots from native plasma with five platelet concentrations. Five species were used to validate the protocol (human, cow, pig, rat, horse). By Lissajous plots the oscillation cycle for each stress level was analyzed. (3) Results: Cyclic stress loading generates a characteristic strain response that scales with the platelet quantity at low stress, and that is independent from the platelet count at high shear stress. This general behavior is valid in the animal models except cow. Here, the specific fibrinogen chemistry induces a stiffer network and a variant high stress response. (4) Conclusions: The protocol provides several thresholds to connect the softening and stiffening behavior of clots with the applied shear stress. This points to the reversible part of deformation, and thus opens a new route to describe a blood clot’s phenotype.

Amoeba Genome Reveals Dominant Host Contribution to Plastid Endosymbiosis.

Eukaryotic photosynthetic organelles, plastids, are the powerhouses of many aquatic and terrestrial ecosystems. The canonical plastid in algae and plants originated >1 Ga and therefore offers limited insights into the initial stages of organelle evolution. To address this issue, we focus here on the photosynthetic amoeba Paulinella micropora strain KR01 (hereafter, KR01) that underwent a more recent (∼124 Ma) primary endosymbiosis, resulting in a photosynthetic organelle termed the chromatophore. Analysis of genomic and transcriptomic data resulted in a high-quality draft assembly of size 707 Mb and 32,361 predicted gene models. A total of 291 chromatophore-targeted proteins were predicted in silico, 208 of which comprise the ancestral organelle proteome in photosynthetic Paulinella species with functions, among others, in nucleotide metabolism and oxidative stress response. Gene coexpression analysis identified networks containing known high light stress response genes as well as a variety of genes of unknown function (“dark” genes). We characterized diurnally rhythmic genes in this species and found that over 49% are dark. It was recently hypothesized that large double-stranded DNA viruses may have driven gene transfer to the nucleus in Paulinella and facilitated endosymbiosis. Our analyses do not support this idea, but rather suggest that these viruses in the KR01 and closely related P. micropora MYN1 genomes resulted from a more recent invasion.

Psychological and physical condition of Japan maritime self-defense force personnel who performed disaster-relief missions after the 2011 great east Japan earthquake

The Great East Japan Earthquake, which occurred on March 11, 2011, was the most powerful earthquake ever recorded in Japan. In the present study, we examine personnel from the Japan Maritime Self-Defense Force who performed disaster relief in the earthquake's aftermath, focusing on the associated psychological and physical impacts. Overall, 8733 personnel were examined. In both July–August 2011 (M1) and July 2012 (M2), these personnel answered the Impact of Events Scale-Revised, the Kessler Psychological Distress Scale, and the Disaster Relief Questionnaire. We also analyzed the sample's physical examination records for the periods before and after the earthquake, using as controls a sample of peers who were not dispatched to the disaster area (N = 32,270). The psychological examinations showed that, in M1, holding the rank of private/sergeant (odds ratio [OR] = 2.13), performing body-recovery duties (OR = 1.94), and having disaster-affected family members (OR = 2.13) were significant risk factors for high post-traumatic stress response (PTSR). In M2, performing body-recovery duties (OR = 1.45) and having disaster-affected family members (OR = 2.60) were significant risk factors for high PTSR. Also, being woman (OR = 2.18) and having disaster-affected family members (OR = 1.68) were significant risk factors for high general psychological distress. For the physical examinations, the mean alanine transaminase in the dispatched group (31.73 ± 25.21) was significantly higher than that in the non-dispatched group (29.56 ± 21.03). These findings suggest that personnel involved in disaster relief experience psychological impacts in the subacute stage, but that these impacts attenuate one year after the event.

The Arabidopsis Nα -acetyltransferase NAA60 locates to the plasma membrane and is vital for the high salt stress response.

In humans and plants, N-terminal acetylation plays a central role in protein homeostasis, affects 80% of proteins in the cytoplasm and is catalyzed by five ribosome-associated N-acetyltransferases (NatA-E). Humans also possess a Golgi-associated NatF (HsNAA60) that is essential for Golgi integrity. Remarkably, NAA60 is absent in fungi and has not been identified in plants. Here we identify and characterize the first plasma membrane-anchored post-translationally acting N-acetyltransferase AtNAA60 in the reference plant Arabidopsis thaliana by the combined application of reverse genetics, global proteomics, live-cell imaging, microscale thermophoresis, circular dichroism spectroscopy, nano-differential scanning fluorometry, intrinsic tryptophan fluorescence and X-ray crystallography. We demonstrate that AtNAA60, like HsNAA60, is membrane-localized in vivo by an α-helical membrane anchor at its C-terminus, but in contrast to HsNAA60, AtNAA60 localizes to the plasma membrane. The AtNAA60 crystal structure provides insights into substrate-binding, the broad substrate specificity and the catalytic mechanism probed by structure-based mutagenesis. Characterization of the NAA60 loss-of-function mutants (naa60-1 and naa60-2) uncovers a plasma membrane-localized substrate of AtNAA60 and the importance of NAA60 during high salt stress. Our findings provide evidence for the plant-specific evolution of a plasma membrane-anchored N-acetyltransferase that is vital for adaptation to stress.

The Effect Of A Ketogenic Diet On The Exercise Induced Immune Response

PURPOSE: Ketogenic diets are popular amongst athletes, they improve fat oxidation capacity and training with low carbohydrate (CHO) availability can possibly enhance training adaptation. However, performance improvements are not observed and training with low CHO availability may increase the susceptibility to illness and infection. Therefore, the aim of this study was to examine the effect of a (short and longer) ketogenic diet on the exercise induced immune response. METHODS: in this cross-over study, 14 well trained male athletes (age 32.9±8.2 years, VO2max 57.3±5.8 ml/kg/min) were assigned to two weeks on a low CHO ketogenic (LC) diet (< 10En% CHO) and two weeks on a high CHO (HC) diet (> 50En% CHO) in a random order, with a wash-out period of >2 weeks in between. Test days were planned after 2 days and 2 weeks on both diets. During test days athletes cycled for 90 minutes at 70% VO2max and blood samples were taken at baseline, directly after exercise and 2hr after exercise. Blood samples were analysed for cortisol, immune cell differential count and homing factors. RESULTS: Total work load performed during the exercise test was lowest after 2 days on the LC diet (938.6±162.5 kJ) and improved after 2 weeks (1003.2±128.6 kJ, p=0.03), but was still lower compared to the HC diet (~1040 kJ, p>0.05). Cortisol response after exercise was higher after 2 days on the LC diet (822±215 nmol/L) compared to the response after 2 weeks on the LC diet (669±243 nmol/L) and compared to both test days during the HC diet (609±208 and 555±173 nmol/L, both p<0.001). Immune cell differential count, for T-cells, Th cells, Cytotoxic T cells, NK T cells, B cells and monocytes was significantly different between diets (p < 0.05). Differences between diets were more pronounced after 2 days on the diets compared to 2 weeks on the diets. The CCR7+ homing factor on CD4+ cells (which guides cells to lymph nodes) was higher during the LC diet, compared to the HC diet (p< 0.05) CONCLUSIONS: The short term ketogenic diet caused a higher stress response and more pronounced differences in cell differentiation, compared to the HC diet. In addition, homing of CD4+ cells to the lymph nodes was stronger on the LC diet compared to the HC diet.

Genotype-Dependent Gene Expression in Strawberry (Fragaria x ananassa) Plants Under High Temperature Stress.

The differences in tolerance to high temperatures were investigated on the basis of gene expressions in two strawberry (Fragaria x ananassa Duch) cultivars which were previously determined as high temperature tolerant (Redlands Hope = R. Hope) and sensitive (Festival). Plants were exposed incrementally to 35, 40, 45, and finally 50 °C for 24h. qRT-PCR analyses were carried out with 19 known sequences from the databases. Protein expression analyses were based on SDS-PAGE results, sequenced and then separated due to their isoelectric points. Expression levels were determined at 35, 40, and 45°C. According to the results, tolerance of 'R. Hope' to high temperature stress can be explained with the coordination of Hsp70, Hsp90, and small heat shock proteins (sHsps) having a vital and supplementary role in stress response. Sensitive cultivar 'Festival' can respond to high temperatures only with the low molecular weight protein and transcripts that do not take a central role in high temperature stress response. Moreover, allergen gene expression triggered by high temperature were detected in both cultivars with different expression levels. The greater expression level in allergen genes observed in the sensitive cultivar 'Festival' under high temperature indicates that there is possibly a negative correlation between expression level in allergen genes and heat stress tolerance. Future studies addressing allergen gene expression under high temperature stress are required to confirm on these findings and to expand on the potential use as a molecular marker in breeding process for enhanced tolerance to high temperature.