Biological Stress Response Research Articles

The use of the model organism Caenorhabditis elegans in the investigation of the adverse effects of electronic cigarettes.

The use of tobacco products is one of the most preventable risk factors for mortality from a variety of diseases, including cardiovascular, infectious, respiratory, and neoplastic conditions. The use of electronic cigarettes (ECIGs), also known as electronic nicotine delivery devices, has increased significantly in recent years. Nicotine, propylene glycol, and / or glycerine, water, alcohol, flavorings, and other substances are among the many chemicals found in ECIGs that are vaporized and inhaled. A review of the existing literature shows that research dedicated to ECIGs is a rapidly developing and growing field of study. The rationale for the use of ECIGs is that they represent a safer alternative to traditional tobacco products. However, vaping safety profiles are still under development, as this is a relatively recent phenomenon. Various model organisms can be employed to examine the cellular processes that may be altered by exposure to the electronic liquids utilized for vaping. For example, the translucent multicellular eukaryote Caenorhabditis elegans is widely used as a model organism to explain a broad range of biological processes, including aging, stress response, development, and many others. Due to its short lifespan and easy use, C. elegans is an ideal model organism for studying chronic exposure to drugs and environmental toxicology. This review presents a summary of the most recent findings on the impact of electronic cigarettes on the physiological health of this nematode. Preliminary observations made in C. elegans can provide insight into the consequences of exposure to fundamental cellular physiology, which can then be used for future research in humans and mammalian models.

Advances in RNA editing in hematopoiesis and associated malignancies.

Adenosine-to-inosine (A-to-I) RNA editing is a prevalent RNA modification essential for cell survival. The process is catalyzed by the Adenosine Deaminase Acting on RNA (ADAR) enzyme family that converts adenosines in double-stranded RNAs (dsRNAs) into inosines, which are read as guanosines during translation. Deep sequencing has helped to reveal that A-to-I editing occurs across various types of RNAs to affect their functions. RNA editing detection is now so sophisticated that we can achieve a high level of accuracy and sensitivity to identify low abundance edited events. Consequently, A-to-I editing has been implicated in various biological processes, including immune and stress responses, cancer progression and stem cell fate determination. In particular, a crucial role for this process has been recently reported in hematopoietic cell development and hematologic malignancy progression. Results from genetic mouse models have demonstrated the impact of ADARs' catalytic activity on hematopoietic cells, complemented by insights from human cell studies. Meanwhile clinical studies have implicated ADAR enzymes and RNA editing events in hematologic malignancies and highlighted their potential as prognostic indicators. In this review, we outline the regulatory mechanisms of RNA editing in both normal hematopoiesis and hematologic malignancies. We then speculate on how targeting ADAR expression and site-specific RNA substrates might serve as a therapeutic avenue for affected patients.

Citrus transcription factor CsERF1 is involved in the response to citrus tristeza disease.

Citrus tristeza virus (CTV) is a threat to the citrus production and causes severe economic losses to the citrus industry. Ethylene response factors (ERFs) play important roles in plant growth and stress responses. Although ERF genes have been widely studied in model plants, little is known about their role in biological stress responses in fruit trees, such as citrus. CsERF1 belongs to the citrus AP2/ERF transcription factor family. To determine the role of CsERF1 on CTV resistance in citrus and the effects of the exongenous hormone application on CsERF1 in citrus, the expression of related genes was quantitatively analyzed by quantitative reverse transcription polymerase chain reaction (RT-qPCR) in this study. The expression profile showed that the expression level of CsERF1 in roots was significantly lower under CTV infection than in healthy plants, while the expression level in stems was significantly increased. CsERF1 responded to exogenous salicylic acid (SA) and methyl jasmonate (MeJA) treatments. The CTV titer in RNAi-CsERF1 transgenic sweet orange plants significantly increased. Furthermore, CsERF1-overexpressing and RNAi-CsERF1 transgenic sweet orange plants exhibited differential expression of genes involved in jasmonic acid (JA) and SA signaling. These results suggest that CsERF1 mediates CTV resistance by regulating the JA and SA signaling pathways. The results of this study provide new clues as to the citrus defence response against CTV. It is of great significance to create citrus germplasm resources resistant to recession disease.

3D chromatin hubs as regulatory units of identity and survival in human acute leukemia.

Cancer progression involves genetic and epigenetic changes that disrupt chromatin 3D organization, affecting enhancer-promoter interactions and promoting growth. Here, we provide an integrative approach, combining chromatin conformation, accessibility, and transcription analysis, validated by in silico and CRISPR-interference screens, to identify relevant 3D topologies in pediatric Tcell leukemia (T-ALL and ETP-ALL). We characterize 3D hubs as regulatory centers for oncogenes and disease markers, linking them to biological processes like cell division, inflammation, and stress response. Single-cell mapping reveals heterogeneous gene activation in discrete epigenetic clones, aiding in patient stratification for relapse risk after chemotherapy. Finally, we identify MYB as a 3D hub regulator in leukemia cells and show that the targeting of key regulators leads to hub dissolution, thereby providing a novel and effective anti-leukemic strategy. Overall, our work demonstrates the relevance of studying oncogenic 3D hubs to better understand cancer biology and tumor heterogeneity and to propose novel therapeutic strategies.

Potential Signal Pathways and Therapeutic Effects of Mesenchymal Stem Cell on Oxidative Stress in Diseases.

Oxidative stress is a biological stress response produced by the destruction of redox equilibrium in aerobic metabolism in organisms, which is closely related to the occurrence of many diseases. Mesenchymal stem cells (MSCs) have been found to improve oxidative stress injury in a variety of diseases, including arthritis, chronic obstructive pulmonary disease, asthma, multiple sclerosis, focal segmental glomerulosclerosis, diabetic nephropathy, ischemia-reperfusion injury, hepatic fibrosis, myocardial infarction, diabetes, inflammatory bowel disease, etc. The antioxidant stress capacity of MSCs may be a breakthrough in the treatment of these diseases. This review found that MSCs have the ability to resist oxidative stress, which may be achieved through MSCs involvement in mediating the Nrf2, MAPK, NF-κB, AMPK, PI3K/AKT and Wnt/b-catenin signaling pathways.

Dimensions of childhood adversity differentially affect autonomic nervous system coordination in response to stress

It is well-established that disrupted autonomic nervous system (ANS) reactivity exacerbates risk for long-term maladjustment following childhood adversity (CA). However, few studies have integrated measures of both the sympathetic (SNS) and parasympathetic (PNS) branches of the ANS, resulting in a unidimensional understanding of ANS functioning as a mechanism of risk. Further, past work has primarily measured CA only at the aggregate level (e.g. “total CA”), necessitating further research to accurately characterize this risk pathway. The present study examines how CA, measured cumulatively and dimensionally (i.e. CA characterized by threat versus deprivation), moderates the association between the SNS and PNS at rest and in response to acute social and nonsocial stressors. Participants included 97 adolescents ages 10-15 (Mage = 12.22, SD age = 1.68) experiencing a range of CA and one accompanying caregiver. Participants completed questionnaires assessing prior CA exposure. SNS and PNS responses were then continuously measured during rest and two stress tasks. First, results indicate a blunting effect of cumulative CA and CA characterized by threat (e.g. physical abuse) on resting SNS activity. Second, in moderation analyses assessing ANS coordination, threat exposure emerged as a significant moderator of the association between SNS and PNS reactivity to social stress. Results suggest that CA characterized by threat may specifically impact physiologic regulation by disrupting the coordination of the two branches of the ANS. Disentangling the independent and concurrent engagement of biological stress response systems following CA remains an important target for research to identify the etiology of aberrant stress reactivity patterns.

Lifetime stressor exposure is related to suicidality in autistic adults: A multinational study.

When we encounter life events that we experience as stressful ("stressors"), it sets off a biological stress response that can impact mental health and contribute to suicidal thoughts and behaviors (STB). Although we know about specific stressors that are associated with STB in the general population, little is known about the kinds of stressors that increase the risk of STB in autistic people and whether these associations differ by gender. To examine this issue, we cataloged the life stressors that autistic men and women experienced over the entire life course and investigated how these stressors were related to STB. Data were derived from a multinational sample of 226 autistic adults from the United Kingdom and Australia who completed the Stress and Adversity Inventory for Adults. We found that autistic men and women differed in terms of both the lifetime stressors they experienced as well as their perceived severity. Whereas men experienced more legal/crime-related stressors, women experienced more stressors related to relationships with other people and more long-lasting stressors associated with humiliation. Autistic women often perceived life stressors as more severe than men, which is important given that it is the perceived severity of stressors that most strongly affects our health. We also found that different stressors may predict STB in autistic men versus women. Whereas loss of loved ones was most strongly associated with STB for men, for women, physically dangerous stressors were most relevant. In addition, women with fewer lifetime stressors involving entrapment had higher lifetime STB. These results suggest that lifetime stressor exposure may be important to assess to understand suicide risk in autistic people. Additional research is needed to confirm these associations and to examine possible mechanisms linking stress and STB.

Psychological and biological stress pathways as common mechanisms underlying a psycho-neurological symptom cluster in cancer patients: Perceived stress, cortisol, and ACTH

PurposeThis study aimed to examine (a) whether psychological stress is associated with experiencing multiple psycho-neurological symptoms (depression, cognitive impairment, fatigue, sleep disturbance, and pain) as a cluster and (b) whether stress hormones (adrenocorticotropic hormone [ACTH] and cortisol) are associated with psychological stress and symptom cluster experience. MethodsThis cross-sectional study analyzed data from 133 patients with hematologic cancer awaiting chemotherapy. Enzyme-linked immunosorbent assays analyzed the morning stress hormone levels (ACTH and cortisol). Latent profile analyses identified the group experiencing a psycho-neurological symptom cluster. Factors influencing the experience of the psycho-neurological symptom cluster were included as covariates and analyzed using multinomial logistic regression. ResultsThirty-three percent (n = 44) experienced all five psycho-neurological symptoms as a cluster and experienced each symptom in a higher severity than those who did not experience the symptom cluster (ps < 0.05). Thereby, this group legitimately experienced the psycho-neurological symptom cluster. The major determinant of this group was the perceived psychological stress (OR = 8.05, 95% CI = 3.08; 20.99). Further, each symptom demonstrated a positive association with stress levels (correlation r ranged from 0.22 to 0. 56, all ps < 0.05). Participants with higher stress were more likely to experience the symptom cluster. Stress hormones levels (ACTH and cortisol) were neither associated with the symptom cluster experience nor with psychological stress levels. ConclusionsPsychological stress, rather than biological stress response, is involved in experiencing the psycho-neurological symptom cluster. Managing stress levels would help alleviate this symptom cluster.

Hydrogel-Based Network Metamaterials with Biological Tissue-like Poisson's Ratio Behavior and Stress Response.

Soft network metamaterials are widely used in fields such as flexible electronics, tissue engineering, and biomedicine due to their superior properties including low density, high stretchability, and high breathability. However, the prediction and customization of the nonlinear mechanical behavior of soft network metamaterials remain a challenging problem. In this study, a family of hydrogel-based network metamaterials with biological tissue-like mechanical properties are developed based on a machine learning-driven optimization design method. Numerical and experimental results explain the relationship between the mechanical properties of the designed metamaterials and their microstructural features and stretching ratios. The results indicate that the hydrogel-based network metamaterials exhibit J-shaped stress-deformation (σ-λ) behavior similar to biological tissues. This phenomenon arises from the transition of the deformation mode of metamaterials from bending-dominated to stretching-dominated as the stretching ratio increases. Based on the proposed design scheme, the Poisson's ratio of metamaterials can be adjusted within a remarkably wide range of -1.06 to 1.34. Furthermore, through optimizing the design parameters of the metamaterial, the customization of network metamaterials with biological tissue-like zero Poisson's ratio behavior and stress response is achieved. The potential applications of hydrogel-based network metamaterials are demonstrated through artificial skin and LED integrated device. This research offers novel insights into predicting, designing, and fabricating the mechanical behavior of soft network metamaterials.

Gene and transcript expression patterns, coupled with isoform switching and long non-coding RNA dynamics in adipose tissue, underlie the longevity of Ames dwarf mice.

Our study investigates gene expression in adipose tissue of Ames dwarf (df/df) mice, whose deficiency in growth hormone is linked to health and extended lifespan. Recognizing adipose tissue influence on metabolism, aging, and related diseases, we aim to understand its contribution to the health and longevity of df/df mice. We have identified gene and transcript expression patterns associated with critical biological functions, including metabolism, stress response, and resistance to cancer. Intriguingly, we identified genes that,despite maintaining unchanged expression levels, switch between different isoforms, impacting essential cellular functions such as tumor suppression, oncogenic activity, ATP transport, and lipid biosynthesis and storage. The isoform switching is associated with changes in protein domains, retention of introns, initiation of nonsense-mediated decay, and emergence of intrinsically disordered regions. Moreover, we detected various alternative splicing events that may drive these structural alterations. We also found changes in the expression of long non-coding RNAs (lncRNAs) that may be involved in the aging process and disease resistance by regulating crucial genes in survival and metabolism. Through weighted gene co-expression network analysis, we have linked four lncRNAs with 29 genes, which contribute to protein complexes such as the Mili-Tdrd1-Tdrd12 complex. Beyond safeguarding DNA integrity, this complex also has a wider impact on gene regulation, chromatin structure, and metabolic control. Our detailed investigation provides insight into the molecular foundations of the remarkable health and longevity of df/df mice, emphasizing the significance of adipose tissue in aging and identifying new avenues for health-promoting therapeutic strategies.

Exogenous MgH2-derived hydrogen alleviates cadmium toxicity through m6A RNA methylation in rice

Cadmium (Cd) contamination poses a substantial threat to crop yields and human health. While magnesium hydride (MgH2) has been reported as a hydrogen (H2) donor that promotes plant growth under heavy metal contamination, its role in rice remains elusive. Herein, seedlings of Oryza sativa L. Japonica variety Zhonghua 11 (ZH11) were selected and exposed to 20 µL of 1-mol/L cadmium chloride (CdCl2) solution via hydroponics to simulate Cd stress. Meanwhile, 0.1 mg of MgH2 was used to slow-release H2 to the experimental group to explore its potential effects on rice over a 2-week period. The results indicated that Cd exposure severely inhibited the growth and development of ZH11 rice seedlings. However, the exogenous slow-release of H2 from MgH2 effectively mitigated this inhibitory effect by restoring the balance of reactive oxygen species (ROS), maintaining endogenous H2 homeostasis, and supporting the photosynthetic system. High-performance liquid chromatography analysis revealed that exogenous H2 reduces m6A RNA methylation levels in mRNA under Cd stress. Consequently, MeRIP-seq was conducted to investigate the effect of Cd exposure in rice in the presence and absence of H2. The m6A modifications were enriched at the start codon, stop codon, and 3′ UTR. By integrating RNA-seq data, 118 transcripts were identified as differentially methylated and expressed genes under Cd stress. These gene annotations were associated with ROS, biological stress, and hormonal responses. Notably, 297 differentially methylated and expressed genes were identified under Cd stress in the presence of H2, linked to heavy metals, protein kinases, and calcium signaling regulation. Cd strongly activates the MAPK pathway in response to stress. Exogenous H2 reduces Cd accumulation as well as enhances plant tolerance and homeostasis by lowering m6A levels, thereby decreasing the mRNA stability of these genes. Our findings indicate that MgH2, by supplying H2, regulates gene expression through m6A RNA methylation and confers Cd tolerance in rice. This study provides potential candidate genes for studying the remediation of heavy metal pollution in plants.

Roles of Histone Acetylation and Deacetylation in Root Development

Roots are usually underground plant organs, responsible for anchoring to the soil, absorbing water and nutrients, and interacting with the rhizosphere. During root development, roots respond to a variety of environmental signals, contributing to plant survival. Histone post-translational modifications play essential roles in gene expression regulation, contributing to plant responses to environmental cues. Histone acetylation is one of the most studied post-translational modifications, regulating numerous genes involved in various biological processes, including development and stress responses. Although the effect of histone acetylation on plant responses to biotic and abiotic stimuli has been extensively reviewed, no recent reviews exist focusing on root development regulation by histone acetylation. Therefore, this review brings together all the knowledge about the impact of histone acetylation on root development in several plant species, mainly focusing on Arabidopsis thaliana. Here, we summarize the role of histone acetylation and deacetylation in numerous aspects of root development, such as stem cell niche maintenance, cell division, expansion and differentiation, and developmental zone determination. We also emphasize the gaps in current knowledge and propose new perspectives for research toward deeply understanding the role of histone acetylation in root development.

Analysis of Biological Stress Response as the Impact of Workplace Bullying on Performance Perception

This study aims to determine the extent to which workplace bullying is related to employees' performance perception at health centers and its impact on biological stress. The research was conducted on all employees at eight health centers in Regency X, randomly selected. Workplace bullying was measured using the Negative Acts Questionnaire Revised (NAQ-R), translated into Indonesian. Performance perception was measured using the Performance Perception Questionnaire. Biological stress was assessed through cortisol levels in saliva. Among the 240 participants, the majority (60%) rarely experienced workplace bullying, with an average score of 41.00 (SD=6.532). Most participants (67.1%) had a high perception of performance, with an average score of 67.12 (SD=9.747). Pearson's test results showed a value of 0.038 with a coefficient of -0.207, indicating a significant correlation between workplace bullying and performance perception. The findings also indicate that biological stress levels, measured through cortisol, correlate with lower performance perceptions. Workplace bullying contributes 4.285% to performance perception. This study provides preliminary evidence that workplace bullying can affect employee performance through biological stress mechanisms, highlighting the importance of interventions to reduce workplace bullying to improve employee well-being and performance

Deep learning enabled in vitro predicting biological tissue thickness using force measurement device

Accurate perception of biological tissues (BT) thickness is essential for preliminary evaluation of medical diagnosis and animal nutrition. However, traditional thickness measuring approaches of BT require complex operation, high-cost, and trigger biological stress response. Herein this study, an novel in vitro BT thickness measuring approach integrated with force test system (FST) and the discrete multiwavelet transform convolutional neural network (DMWA-CNN) prediction model based on deep learning are proposed. Simultaneously, several comprehensive experiments and model comparisons are conducted to demonstrate the superiority of the proposed approach. By establishing a DMWA-CNN demonstrates higher estimation accuracy than other traditional algorithm, achieving 100 % accuracy for artificial BT. Moreover, the experimental results indicate that proposed approach is robust to elastic modulus variation (E), external load variation (F), and small thickness differences (Ts). In addition, four kinds of the pork’ thickness are experimentally measured, and the accuracy value is not less than 98.2 %. The thickness of BT determined using the FST and DMWA-CNN algorithm demonstrate potential application in the biomechanical parameter prediction.

Unravelling Morpho‐Physiological Mechanism and Candidate Genes Associated With Salinity Tolerance in Superior Haplotypes of Barley (Hordeum vulgare L.)

ABSTRACTThe lack of suitable genetic resources for saline regions and the complexity of the traits involved impede the progress in crop breeding for salt tolerance. The present investigation was carried out using 27 diverse barley genotypes chosen based on the assessment of salt tolerance potential within the barley mini‐core collection at the National Genebank of India. The genotypes were exposed to salinity stress (200 mM NaCl) and were examined for morpho‐agronomic, physiological traits and salt uptake parameters. Exposure to salt stress resulted in a significant decline in all parameters ranging from 5.94% in relative water content to 80.04% in shoot K+/Na+ ratio compared to the control in the evaluated accessions. Moreover, the grain yield and its key attribute hundred‐grain weight decreased substantially by 65.35% and 48.62%, respectively, under saline treatment. The majority of the resilient accessions managed to uphold a higher K+/Na+ ratio ranging from 0.51 in EC0578359 to 1.19 EC0578251 in contrast to vulnerable germplasm (&lt;0.56) under saline circumstances. The analysis of haplotype variants disclosed allelic diversity linked with two promising candidate genes, HVA1 and HvHKT2, recognised for conferring salt tolerance. Examination of nucleotide sequences revealed that the HVA1 remained considerably conserved among the evaluated genotypes as the majority of the SNPs (single‐nucleotide polymorphisms) were synonymous. Conversely, for HvHKT2, a significant level of genetic variation led to the identification of two primary haplotypic clusters—Hap1 associated with sensitivity to salinity and Hap2 linked with tolerant traits. Hap2 predominantly consisted of In/Dels which caused a modification in the overall protein length alongside the phospho‐variant allelic form of the HKT2 gene, further enhancing the biological specificity and functional stress response in a spatiotemporal fashion. These haplotype clusters correlated with favourable traits could be utilised for trait integration into breeding populations, thereby expediting the enhancement of superior salt‐tolerant barley cultivars.

Study on the Function of SlWRKY80 in Tomato Defense against Meloidogyne incognita.

WRKY transcription factors (TFs) can participate in plant biological stress responses and play important roles. SlWRKY80 was found to be differentially expressed in the Mi-1- and Mi-3-resistant tomato lines by RNA-seq and may serve as a key node for disease resistance regulation. This study used RNAi to determine whether SlWRKY80 silencing could influence the sensitivity of 'M82' (mi-1/mi-1)-susceptible lines to M. incognita. Further overexpression of this gene revealed a significant increase in tomato disease resistance, ranging from highly susceptible to susceptible, combined with the identification of growth (plant height, stem diameter, and leaf area) and physiological (soluble sugars and proteins; root activity) indicators, clarifying the role of SlWRKY80 as a positive regulatory factor in tomato defense against M. incognita. Based on this phenomenon, a preliminary exploration of its metabolic signals revealed that SlWRKY80 stimulates different degrees of signaling, such as salicylic acid (SA), jasmonic acid (JA), and ethylene (ETH), and may synergistically regulate reactive oxygen species (ROS) accumulation and scavenging enzyme activity, hindering the formation of feeding sites and ultimately leading to the reduction of root gall growth. To our knowledge, SlWRKY80 has an extremely high utilization value for improving tomato resistance to root-knot nematodes and breeding.

Genome-Wide Identification and Characterization of U-Box Gene Family Members and Analysis of Their Expression Patterns in Phaseolus vulgaris L. under Cold Stress.

The common bean (Phaseolus vulgaris L.) is an economically important food crop grown worldwide; however, its production is affected by various environmental stresses, including cold, heat, and drought stress. The plant U-box (PUB) protein family participates in various biological processes and stress responses, but the gene function and expression patterns of its members in the common bean remain unclear. Here, we systematically identified 63 U-box genes, including 8 tandem genes and 55 non-tandem genes, in the common bean. These PvPUB genes were unevenly distributed across 11 chromosomes, with chromosome 2 holding the most members of the PUB family, containing 10 PUB genes. The analysis of the phylogenetic tree classified the 63 PUB genes into three groups. Moreover, transcriptome analysis based on cold-tolerant and cold-sensitive varieties identified 4 differentially expressed PvPUB genes, suggesting their roles in cold tolerance. Taken together, this study serves as a valuable resource for exploring the functional aspects of the common bean U-box gene family and offers crucial theoretical support for the development of new cold-tolerant common bean varieties.

Parents' work demands on next day's cortisol awakening response - the moderating role of family-to-work conflict

BackgroundConstant availability, overtime and feeling overwhelmed by work can impact employees' wellbeing and their biological stress responses. Especially working parents often struggle to balance the demands of their work and family life and were found to be distracted from their work due to family responsibilities. The Family-to-Work Conflict (FWC) indicates the extent to which participating in work is made difficult by family demands. Recent studies have found associations between FWC and biological outcomes such as the Cortisol Awakening Response (CAR), a measure of an individual's Hypothalamic-Pituitary-Adrenal (HPA)-axis activity. This diary study investigates the effect of parental work demands on next day's cortisol response as well as the moderating role of FWC and the mediating role of fatigue. MethodsOver the course of five consecutive days (from Monday to Friday), 168 observations were made on a total of 42 parents. Participants had at least one child and worked a minimum of 20 hours per week. Salivary cortisol samples were obtained immediately, 15 and 30 minutes after awakening each day. Work demands, FWC and fatigue were assessed using standardized questionnaires. Within-person effects were examined using multilevel modeling and mediation analyses. ResultsOur results indicate that there are no main effects of work demands on next day's cortisol response. The multilevel analysis revealed that FWC predicts lower wakening cortisol levels and confirmed FWC as an increasing moderator between work demands and next day's HPA-axis activity. Further, work overload was found to increase fatigue, which in turn leads to higher CAR on the following day. This indicates that fatigue mediates the relationship between work demands and CAR. Our findings add to a growing body of research demonstrating further predictors for HPA-axis activity and emphasise the importance of considering family related demands when investigating biological outcomes for working parents.

Expression of Stress-Induced Genes in Bronchoalveolar Lavage Cells and Lung Fibroblasts from Healthy and COPD Subjects.

Chronic obstructive pulmonary disease (COPD) is commonly caused from smoking cigarettes that induce biological stress responses. Previously we found disorganized endoplasmic reticulum (ER) in fibroblasts from COPD with different responses to chemical stressors compared to healthy subjects. Here, we aimed to investigate differences in stress-related gene expressions within lung cells from COPD and healthy subjects. Bronchoalveolar lavage (BAL) cells were collected from seven COPD and 35 healthy subjects. Lung fibroblasts were derived from 19 COPD and 24 healthy subjects and exposed to cigarette smoke extract (CSE). Gene and protein expression and cell proliferation were investigated. Compared to healthy subjects, we found lower gene expression of CHOP in lung fibroblasts from COPD subjects. Exposure to CSE caused inhibition of lung fibroblast proliferation in both groups, though the changes in ER stress-related gene expressions (ATF6, IRE1, PERK, ATF4, CHOP, BCL2L1) and genes relating to proteasomal subunits mostly occurred in healthy lung fibroblasts. No differences were found in BAL cells. In this study, we have found that lung fibroblasts from COPD subjects have an atypical ER stress gene response to CSE, particularly in genes related to apoptosis. This difference in response to CSE may be a contributing factor to COPD progression.

Functional and regulatory diversity of homeobox-leucine zipper transcription factors BnaHB6 under dehydration and salt stress in Brassica napus L.

The plant-specific homeodomain-leucine zipper I subfamily is involved in the regulation of various biological processes, particularly growth, development and stress response. In the present study, we characterized four BnaHB6 homologues from Brassica napus. All BnaHB6 proteins have transcriptional activation activity. Structural and functional data indicate the complex role of BnaHB6 genes in regulating biological processes, with some functions conserved and others diverged. Transcriptional analyzes revealed that they are induced in a similar manner in different tissues but show different expression patterns in response to stress and circadian rhythm. Only the BnaA09HB6 and BnaC08HB6 genes are expressed under dehydration and salt stress, and in darkness. The partial transcriptional overlap of BnaHB6s with the evolutionarily related genes BnaHB5 and BnaHB16 was also observed. Transgenic Arabidopsis thaliana plants expressing a single proBnaHB6::GUS partially confirmed the expression results. Bioinformatic analysis allowed the identification of TF-binding sites in the BnaHB6 promoters that may control their expression under stress and circadian rhythm. ChIP-qPCR analysis revealed that BnaA09HB6 and BnaC08HB6 bind directly to the promoters of the target genes BnaABF4 and BnaDREB2A. Comparison of their expression patterns in the WT plants and the bnac08hb6 mutant showed that BnaC08HB6 positively regulates the expression of the BnaABF4 and BnaDREB2A genes under dehydration and salt stress. We conclude that four BnaHB6 homologues have distinct functions in response to stress despite high sequence similarity, possibly indicating different binding preferences with BnaABF4 and BnaDREB2A. We hypothesize that BnaC08HB6 and BnaA09HB6 function in a complex regulatory network under stress.