Stress-responsive Genes Research Articles

Investigating the involvement of potato (Solanum tuberosum L.) StPHR1 gene in the combined stress response to phosphorus deficiency and aluminum toxicity.

Phosphorus deficiency and aluminum toxicity in acidic soils are important factors that limit crop yield. To further explore this issue, we identified 18 members of the StPHR gene family in the potato genome in this study. Through bioinformatics analysis, we found that the StPHR1 gene, an important member of this family, exhibited high expression levels in potato roots, particularly under conditions of phosphorus deficiency and aluminum toxicity stress. This suggested that the StPHR1 gene may play a crucial regulatory role in potato's resistance to phosphorus deficiency and aluminum toxicity. To validate this hypothesis, we conducted a series of experiments on the StPHR1 gene, including subcellular localization, GUS staining for tissue expression, heterologous overexpression, yeast two-hybrid hybridization, and bimolecular fluorescence complementation (BiFC). The results demonstrated that the StPHR1 gene is highly conserved in plants and is localized in the nucleus of potato cells. The heterologous overexpression of the gene in Arabidopsis plants resulted in a growth phenotype that exhibited resistance to both aluminum toxicity and phosphorus deficiency. Moreover, the heterologous overexpressing plants showed reduced aluminum content in the root system compared to the control group. Furthermore, we also identified an interaction between StPHR1 and StALMT6. These results highlight the potential application of regulating the expression of the StPHR1 gene in potato production to enhance its adaptation to the dual stress of phosphorus deficiency and high aluminum toxicity in acidic soils.

Transcriptome- and genome-wide systematic identification of expansin gene family and their expression in tuberous root development and stress responses in sweetpotato (Ipomoea batatas).

Expansins (EXPs) are essential components of the plant cell wall that function as relaxation factors to directly promote turgor-driven expansion of the cell wall, thereby controlling plant growth and development and diverse environmental stress responses. EXPs genes have been identified and characterized in numerous plant species, but not in sweetpotato. In the present study, a total of 59 EXP genes unevenly distributed across 14 of 15 chromosomes were identified in the sweetpotato genome, and segmental and tandem duplications were found to make a dominant contribution to the diversity of functions of the IbEXP family. Phylogenetic analysis showed that IbEXP members could be clustered into four subfamilies based on the EXPs from Arabidopsis and rice, and the regularity of protein motif, domain, and gene structures was consistent with this subfamily classification. Collinearity analysis between IbEXP genes and related homologous sequences in nine plants provided further phylogenetic insights into the EXP gene family. Cis-element analysis further revealed the potential roles of IbEXP genes in sweetpotato development and stress responses. RNA-seq and qRT-PCR analysis of eight selected IbEXPs genes provided evidence of their specificity in different tissues and showed that their transcripts were variously induced or suppressed under different hormone treatments (abscisic acid, salicylic acid, jasmonic acid, and 1-aminocyclopropane-1-carboxylic acid) and abiotic stresses (low and high temperature). These results provide a foundation for further comprehensive investigation of the functions of IbEXP genes and indicate that several members of this family have potential applications as regulators to control plant development and enhance stress resistance in plants.

Genome-Wide Characterization and Analysis of the SPL Gene Family in Eucalyptus grandis.

SQUAMOSA promoter-binding protein-like (SPL) gene family, a group of plant-specific transcription factors, played crucial roles in regulating plant growth, development, signal transduction, and stress response. This study focuses on the SPL gene family in the fast-growing Eucalyptus grandis, employing bioinformatics approaches to identify and analyze the gene physiochemical characteristics, conserved domains, structural composition, chromosomal distribution, phylogenetic relationships, cis-acting elements, and their expression patterns in various tissues and stress treatments. Twenty-three SPL genes were identified in E. grandis, which uneven distributed across seven chromosomes and classified into five groups. Prediction of cis-acting elements revealed that these genes might be related to light, hormone, and stress responses. Furthermore, EgSPL9 and EgSPL23, mainly expressed in the stem apex and lateral branches, seem to be involved in hormone stress resistance. Our study provides insights into the potential functions of the EgSPL genes in plant growth, stress response, and hormone transduction, offering valuable perspectives for subsequent research into their biological roles.

Genome-wide analysis of WRKY gene family and the dynamic responses of key WRKY genes involved in cadmium stress in Brassica juncea.

The WRKY transcription factors comprise one of the most extensive gene families and serve as pivotal regulators of plant responses to heavy metal stress. They contribute significantly to maintaining plant growth and development by enhancing plant tolerance. However, research on the role of WRKY genes in response to cadmium (Cd) stress in mustard is minimal. In this study, we conducted a genome-wide analysis of the mustard WRKY gene family using bioinformatics. The results revealed that 291 WRKY putative genes (BjuWRKYs) were identified in the mustard genome. These genes were categorized into seven subgroups (I, IIa-e and III) through phylogenetic analysis, with differences in motif composition between each subgroup. Homology analysis indicated that 31.62% of the genes originated from tandem duplication events. Promoter analysis revealed an abundance of abiotic stress-related elements and hormone-related elements within the BjuWRKY genes. Transcriptome analysis demonstrated that most BjuWRKY genes exhibited differential expression patterns at different Cd treatment stages in mustard. Furthermore, 10 BjuWRKY genes were confirmed to respond to Cd stress through the construction of a BjuWRKY protein interaction network, prediction of hub genes, and real-time fluorescence quantitative PCR analysis, indicating their potential involvement in Cd stress. Our findings provide a comprehensive insight into the WRKY gene family in mustard and establish a foundation for further studies of the functional roles of BjuWRKY genes in Cd stress response.

Cortisol controls endoplasmic reticulum stress and hypoxia dependent regulation of insulin receptor and related genes expression in HEK293 cells.

Objective. Glucocorticoids are important stress-responsive regulators of insulin-dependent metabolic processes realized through specific changes in genome function. The aim of this study was to investigate the impact of cortisol on insulin receptor and related genes expression in HEK293 cells upon induction the endoplasmic reticulum (ER) stress by tunicamycin and hypoxia. Methods. The human embryonic kidney cell line HEK293 was used. Cells were exposed to cortisol (10 µM) as well as inducers of hypoxia (dimethyloxalylglycine, DMOG; 0.5 mM) and ER stress (tunicamycin; 0.2 µg/ml) for 4 h. The RNA from these cells was extracted and reverse transcribed. The expression level of INSR, IRS2, and INSIG2 and some ER stress responsive genes encoding XBP1n, non-spliced variant, XBP1s, alternatively spliced variant of XBP1, and DNAJB9 proteins, was measured by quantitative polymerase chain reaction and normalized to ACTB. Results. We showed that exposure of HEK293 cells to cortisol elicited up-regulation in the expression of INSR and DNAJB9 genes and down-regulation of XBP1s, XBP1n, IRS2, and INSIG2 mRNA levels. At the same time, induction of hypoxia by DMOG led to an up-regulation of the expression level of most studied mRNAs: XBP1s and XBP1n, IRS2 and INSIG2, but did not change significantly INSR and DNAJB9 gene expression. We also showed that combined impact of cortisol and hypoxia introduced the up-regulation of INSR and suppressed XBP1n mRNA expression levels. Furthermore, the exposure of HEK293 cells to tunicamycin affected the expression of IRS2 gene and increased the level of XBP1n mRNA. At the same time, the combined treatment of these cells with cortisol and inductor of ER stress had much stronger impact on the expression of all the tested genes: strongly increased the mRNA level of ER stress dependent factors XBP1s and DNAJB9 as well as INSR and INSIG2, but down-regulated IRS2 and XBP1n. Conclusion. Taken together, the present study indicates that cortisol may interact with ER stress and hypoxia in the regulation of ER stress dependent XBP1 and DNAJB9 mRNA expression as well as INSR and its signaling and that this corticosteroid hormone modified the impact of hypoxia and especially tunicamycin on the expression of most studied genes in HEK293 cells. These data demonstrate molecular mechanisms of glucocorticoids interaction with ER stress and insulin signaling at the cellular level.

NFXL1 functions as a transcriptional activator required for thermotolerance at reproductive stage in Arabidopsis.

Plants are highly susceptible to abiotic stresses, particularly heat stress during the reproductive stage. However, the specific molecular mechanisms underlying this sensitivity remain largely unknown. In the current study, we demonstrate that the Nuclear Transcription Factor, X-box Binding Protein 1-Like 1 (NFXL1), directly regulates the expression of DEHYDRATION-RESPONSIVE ELEMENT-BINDING PROTEIN 2A (DREB2A), which is crucial for reproductive thermotolerance in Arabidopsis. NFXL1 is upregulated by heat stress, and its mutation leads to a reduction in silique length (seed number) under heat stress conditions. RNA-Seq analysis reveals that NFXL1 has a global impact on the expression of heat stress responsive genes, including DREB2A, Heat Shock Factor A3 (HSFA3) and Heat Shock Protein 17.6 (HSP17.6) in flower buds. Interestingly, NFXL1 is enriched in the promoter region of DREB2A, but not of either HSFA3 or HSP17.6. Further experiments using electrophoretic mobility shift assay have confirmed that NFXL1 directly binds to the DNA fragment derived from the DREB2A promoter. Moreover, effector-reporter assays have shown that NFXL1 activates the DREB2A promoter. The DREB2A mutants are also heat stress sensitive at the reproductive stage, and DEREB2A is epistatic to NFXL1 in regulating thermotolerance in flower buds. It is known that HSFA3, a direct target of DREB2A, regulates the expression of heat shock proteins genes under heat stress conditions. Thus, our findings establish NFXL1 as a critical upstream regulator of DREB2A in the transcriptional cassette responsible for heat stress responses required for reproductive thermotolerance in Arabidopsis.

Elucidating the regulatory role of long non-coding RNAs in drought stress response during seed germination in leaf mustard.

Leaf mustard (Brassica juncea L. Czern & Coss), an important vegetable crop, experiences pronounced adversity due to seasonal drought stress, particularly at the seed germination stage. Although there is partial comprehension of drought-responsive genes, the role of long non-coding RNAs (lncRNAs) in adjusting mustard's drought stress response is largely unexplored. In this study, we showed that the drought-tolerant cultivar 'Weiliang' manifested a markedly lower base water potential (-1.073MPa vs -0.437 MPa) and higher germination percentage (41.2% vs 0%) than the drought-susceptible cultivar 'Shuidong' under drought conditions. High throughput RNA sequencing techniques revealed a significant repertoire of lncRNAs from both cultivars during germination under drought stress, resulting in the identification of 2,087 differentially expressed lncRNAs (DELs) and their correspondingly linked 12,433 target genes. It was noted that 84 genes targeted by DEL exhibited enrichment in the photosynthesis pathway. Gene network construction showed that MSTRG.150397, a regulatory lncRNA, was inferred to potentially modulate key photosynthetic genes (Psb27, PetC, PetH, and PsbW), whilst MSTRG.107159 was indicated as an inhibitory regulator of six drought-responsive PIP genes. Further, weighted gene co-expression network analysis (WGCNA) corroborated the involvement of light intensity and stress response genes targeted by the identified DELs. The precision and regulatory impact of lncRNA were verified through qPCR. This study extends our knowledge of the regulatory mechanisms governing drought stress responses in mustard, which will help strategies to augment drought tolerance in this crop.

Infectivity responses of Salmonella enterica to bacteriophages on maize seeds and maize sprouts

Salmonella enterica (S. enterica) is a major foodborne pathogen leading to a large number of outbreaks and bringing food safety concerns to sprouts. The control of S. enterica on maize sprouts is important because raw maize sprouts have been gaining attention as a novel superfood. Compared to conventional chemical methods, the applications of bacteriophages are regarded as natural and organic. This study investigated the effects of a 2 h phage cocktail (SF1 and SI1, MOI 1000) soaking on reducing the populations of three Salmonella enterica strains: S. Enteritidis S5-483, S. Typhimurium S5-536, and S. Agona PARC5 on maize seeds and during the storage of maize sprouts. The results showed that the phage cocktail treatment effectively reduced populations of S. enterica strains by 1–3 log CFU/g on maize seeds and decreased population of S. Agona PACR5 by 1.16 log CFU/g on maize sprouts from 7.55 log CFU/g at day 0 of the storage period. On the other hand, the upregulations of flagella gene pefA by 1.5-folds and membrane gene lpxA by 23-folds in S. Typhimurium S5-536 indicated a differential response to the phage cocktail treatment. Conversely, stress response genes ompR, rpoS, and recA, as well as the DNA repair gene yafD, were downregulated in S. Agona PARC5. This work shows the use of bacteriophages could contribute as a part of hurdle effect to reduce S. enterica populations and is beneficial to develop strategies for controlling foodborne pathogens in the production and storage of maize sprouts.

Analysis of translesion polymerases in colorectal cancer cells following cetuximab treatment: A network perspective.

Adaptive mutagenesis observed in colorectal cancer (CRC) cells upon exposure to EGFR inhibitors contributes to the development of resistance and recurrence. Multiple investigations have indicated a parallel between cancer cells and bacteria in terms of exhibiting adaptive mutagenesis. This phenomenon entails a transient and coordinated escalation of error-prone translesion synthesis polymerases (TLS polymerases), resulting in mutagenesis of a magnitude sufficient to drive the selection of resistant phenotypes. In this study, we conducted a comprehensive pan-transcriptome analysis of the regulatory framework within CRC cells, with the objective of identifying potential transcriptome modules encompassing certain translesion polymerases and the associated transcription factors (TFs) that govern them. Our sampling strategy involved the collection of transcriptomic data from tumors treated with cetuximab, an EGFR inhibitor, untreated CRC tumors, and colorectal-derived cell lines, resulting in a diverse dataset. Subsequently, we identified co-regulated modules using weighted correlation network analysis with a minKMEtostay threshold set at 0.5 to minimize false-positive module identifications and mapped the modules to STRING annotations. Furthermore, we explored the putative TFs influencing these modules using KBoost, a kernel PCA regression model. Our analysis did not reveal a distinct transcriptional profile specific to cetuximab treatment. Moreover, we elucidated co-expression modules housing genes, for example, POLK, POLI, POLQ, REV1, POLN, and POLM. Specifically, POLK, POLI, and POLQ were assigned to the "blue" module, which also encompassed critical DNA damage response enzymes, for example. BRCA1, BRCA2, MSH6, and MSH2. To delineate the transcriptional control of this module, we investigated associated TFs, highlighting the roles of prominent cancer-associated TFs, such as CENPA, HNF1A, and E2F7. We found that translesion polymerases are co-regulated with DNA mismatch repair and cell cycle-associated factors. We did not, however, identified any networks specific to cetuximab treatment indicating that the response to EGFR inhibitors relates to a general stress response mechanism.

ВПЛИВ ТЕМПЕРАТУРИ ЛИЧИНКОВОЇ СТАДІЇ РОЗВИТКУ НА ЕКСПРЕСІЮ ГЕНІВ HSP70, INR, SIRT1, MTOR ТА FOXO У САМЦІВ І САМОК DROSOPHILA MELANOGASTER

Background. Despite the progress in understanding the phenomenon of aging, the key factors that influence this process remain poorly understood. Aging is a genetically programmed set of events, leading to structural and functional changes that reduce the life expectancy of an organism. The relevance of the study is to expand the understanding of the impact of environmental factors, in particular temperature, on the early stages of development on the life expectancy of imago, using Drosophila melanogaster as a model. The aim was to determine and analyze the expression level of genes associated with lifespan in D. melanogaster – Hsp70, InR, Sirt1, mTor and foxo – in flies reared at different temperatures of the larval stage of development. Methods. The larvae were kept at different temperatures, after which the gene expression level was determined by RT-qPCR in adult flies. The relative expression level was calculated by using the 2-ΔΔCt method. The data were analyzed using ANOVA-test followed by a pairwise multiple comparison post-hoc Tukey HSD test. Differences were considered significant at p˂0.05. Results. The temperature of the larval stage of development did not significantly affect the gene expression of male adults. Аt the same time in females imago a significant increase in the expression of Hsp70, InR, Sirt1 and mTor genes was observed in individuals with larval development took at 20°C and 30°C, compared to the control at 25°C. Conclusions. The increased expression levels of the genes chosen for analysis under the critical temperature conditions indicates the induction of a generalized stress response that did not correlate with an increased life expectancy. The finding of sex differences in gene expression patterns requires further investigation to uncover the molecular mechanisms underlying it.

Assessment of extracellular polymeric substances production and antioxidant defences in periphytic communities exposed to effluent contaminants.

Periphyton is frequently used in the evaluation of the ecological status of aquatic ecosystems using diatoms as a proxy. However, periphyton has a particularity, the production of extracellular polymeric substances (EPS), which might play a protective role against exposure to harmful environmental contaminants. Effluents originating in wastewater treatment plants (WWTPs) constitute some of the most complex mixtures of contaminants, to which aquatic ecosystems are frequently exposed, often containing tens to hundreds of different chemicals. In such challenging scenarios, a putative protective role of EPS may obscure the bioindicator value of diatoms. To address this problem, we sampled periphyton upstream and downstream of the effluent outfall from three different WWTPs, quantifying EPS production and simultaneously evaluating general stress responses in the community (protein and sugar content, photosynthetic pigments, antioxidant enzyme activity and oxidative damage). By combining these endpoints with a characterization of the sediments of the riverine systems receiving the effluents made in a previous study (metals, polycyclic aromatic hydrocarbons, pharmaceuticals and personal care products), we aimed to elucidate whether effluent contaminants trigger negative effects, which may be mitigated by EPS layers protecting the communities. Our results indicated that under a comparatively milder contamination burden, EPS production is enhanced in samples collected downstream of the effluent outfall; under a higher contamination burden, EPS production is hampered. Stress-coping mechanisms were activated by environmental contaminants, including the antioxidant defense, particularly through catalase and superoxide dismutase activity. The findings support the generally assumed protective effect of EPS, but also suggest that EPS production depends on the contamination burden and that protective effects should be in place under specific scenarios of, for example, relatively low contamination levels. Overall, the integrative approach used in this study contributes to a better understanding of the complex interplay of interactions between effluent-driven contamination and thriving periphytic communities inhabiting recipient waterways, including evolved protection mechanisms.

Advances in Physalis molecular research: applications in authentication, genetic diversity, phylogenetics, functional genes, and omics.

The plants of the genus Physalis L. have been extensively utilized in traditional and indigenous Chinese medicinal practices for treating a variety of ailments, including dermatitis, malaria, asthma, hepatitis, and liver disorders. The present review aims to achieve a comprehensive and up-to-date investigation of the genus Physalis, a new model crop, to understand plant diversity and fruit development. Several chloroplast DNA-, nuclear ribosomal DNA-, and genomic DNA-based markers, such as psbA-trnH, internal-transcribed spacer (ITS), simple sequence repeat (SSR), random amplified microsatellites (RAMS), sequence-characterized amplified region (SCAR), and single nucleotide polymorphism (SNP), were developed for molecular identification, genetic diversity, and phylogenetic studies of Physalis species. A large number of functional genes involved in inflated calyx syndrome development (AP2-L, MPF2, MPF3, and MAGO), organ growth (AG1, AG2, POS1, and CNR1), and active ingredient metabolism (24ISO, DHCRT, P450-CPL, SR, DUF538, TAS14, and 3β-HSB) were identified contributing to the breeding of novel Physalis varieties. Various omic studies revealed and functionally identified a series of reproductive organ development-related factors, environmental stress-responsive genes, and active component biosynthesis-related enzymes. The chromosome-level genomes of Physalis floridana Rydb., Physalis grisea (Waterf.) M. Martínez, and Physalis pruinosa L. have been recently published providing a valuable resource for genome editing in Physalis crops. Our review summarizes the recent progress in genetic diversity, molecular identification, phylogenetics, functional genes, and the application of omics in the genus Physalis and accelerates efficient utilization of this traditional herb.

Transcriptome analysis and identification of the low potassium stress-responsive gene SiSnRK2.6 in foxtail millet (Setaria italica L.).

The transcriptome is beneficial for dissecting the mechanism of millet in response to low potassium stress and SiSnRK2.6 was identified as a potential target for improving low potassium stress tolerance. Foxtail millet (Setaria italica L.), which originated in China, has high nutrient utilization character. Nevertheless, the molecular mechanism of its tolerance to low potassium stress is largely unclear. In this research, the low potassium tolerant variety "Yugu28" was screened out by low potassium stress treatment, and the transcriptome of "Yugu28" under low potassium stress was comprehensively analyzed. A total of 4254 differentially expressed genes (DEGs) were identified, including 1618 up-regulated and 2636 down-regulated genes, respectively. In addition, there were 302 transcription factor (TF) genes in the DEGs and MYB TFs accounted for the highest proportion, which was 14.9%. After functional analysis of all DEGs, a total of 7 genes involved in potassium transport and potassium ion channels and 50 genes corresponding to hormones were screened. The expression levels of randomly selected 17 DEGs were verified by qRT-PCR and the results coincided well with the RNA-seq analysis, indicating the reliability of our transcriptome data. Moreover, one of the ABA signaling pathway genes, SiSnRK2.6, was identified and selected for further functional verification. Compared with the wild type, transgenic rice with ecotopic expression of SiSnRK2.6 showed remarkably increased root length and root number, indicating that overexpression of SiSnRK2.6 can enhance the resistance of transgenic plants to low potassium stress.

Generating Mutant for a Stress-Responsive Gene in Rice Using CRISPR-Cas9 System.

CRISPR/Cas9 system is one of the most often utilized engineering tools for genome editing in many organisms including crop plants and presents great value in both basic and applied research. This is a preferred method because of its relative simplicity, cost-effectiveness, and reliability. The Cas9 nuclease guided by a short single guide RNA (gRNA) can generate double-strand DNA breaks (DSB) at the specific sites in chromosomal DNA. The DSB site is repaired by error-prone repair methods. During repair, some nucleotides are deleted or added at the target site. Here, we present a simplified protocol for generating mutants in gene of interest in rice using CRISPR/Cas9.

Identification of abiotic stress-responsive genes: a genome-wide analysis of the cytokinin response regulator gene family in rice.

Response regulators (RRs) are implicated in various developmental processes as well as environmental responses by acting as either positive or negative regulators, and are crucial components of cytokinin signaling in plants. We characterized 36 RRs in rice (Oryza sativa L.; Os) using in silico analysis of publicly available data. A comprehensive analysis of OsRR family members covered their physicochemical properties, chromosomal distribution, subcellular localization, phylogeny, gene structure, distribution of conserved motifs and domains, and gene duplication events. Gene Ontology analysis indicated that 22 OsRR genes contribute mainly to the cytokinin response and signal transduction. Predicted cis-elements in RR promoter sequences related to phytohormones and abiotic stresses indicated that RRs are involved in hormonal and environmental responses, supporting previous studies. MicroRNA (miRNA) target analysis showed that 148 miRNAs target 29 OsRR genes. In some cases, multiple RRs are targets of the same miRNA group, and may be controlled by common stimulus responses. Based on the analysis of publicly available gene expression data, OsRR4, OsRR6, OsRR9, OsRR10, OsRR22, OsPRR73 and OsPRR95 were found to be involved in responses to abiotic stresses. Using quantitative reverse transcription polymerase chain reaction we confirmed that six of these RRs, namely OsRR4, OsRR6, OsRR9, OsRR10, OsRR22 and OsPRR73, are involved in the response to salinity, osmotic, alkaline and wounding stresses, and can potentially be used as models to understand molecular mechanisms underlying stress responsiveness.

Investigating Circadian Gating of Temperature Responsive Genes.

Understanding gene expression dynamics in the context of the time of day and temperature response is an important part of understanding plant thermotolerance in a changing climate. Performing "gating" experiments under constant conditions and light-dark cycles allows users to identify and dissect the contribution of the time of day and circadian clock to the dynamic nature of stress-responsive genes. Here, we describe the design of specific laboratory experiments in plants (Arabidopsis thaliana and bread wheat, Triticum aestivum) to investigate temporal responses to heat (1h at 37°C) or cold (3h at 4°C), and we include known marker genes that have circadian-gated responses to temperature changes.

Plant growth-promoting rhizobacteria: Influence to abiotic stress tolerance in rice (Oryza sativa L.)

Plant growth-promoting rhizobacteria (PGPR) has been shown to govern a number of aspects of plant development, enabling the plant to survive and adapt to its surroundings, in response to unfavorable conditions that are abiotic in nature. As a staple crop, rice is particularly vulnerable to a variety of abiotic stresses including drought, salt, heavy metal toxicity, and high temperatures. In tandem, these stresses have a significant detrimental impact on rice productivity and quality. PGPR is a rhizosphere-dwelling microorganism that can improve plant development through a variety of distinctive methods, including nutrient uptake, phytohormone synthesis, modification of plant stress signaling pathways, and stimulation of stress-responsive genes. In this review, we studied the several abiotic pressures that are encountered and how PGPR can aid in resisting the stresses with a focus on rice crop, we additionally look at how PGPR minimize the dependency of agricultural soils on pesticides and chemical fertilizers. PGPR contributes to the long-term sustainability of ecosystems, plant productivity, and soil health by promoting environmentally friendly and sustainable farming practices.

Characterization of epigenetic modifications in a plant-specific glutaredoxin-mediated repression of stress-responsive gene expression

In eukaryotic cells, epigenetic modifications of DNA and histone play an important role in the regulation of gene expression. ROXY19 is a member of the plant specific CC-type glutaredoxins (GRXs). We found previously that ROXY19, by association with the TOPLESS/TOPLESS-related (TPL/TPR) family, strongly represses a subset of genes which were positively regulated by the class II TGA factors. Arabidopsis plants ectopic expressing ROXY19 (ROXY19OE) were hypersensitive to xenobiotic chemicals due to the silencing of detoxification pathway genes. Here, we confirmed in vivo the interaction between ROXY19 and TPL. In order to understand the molecular mechanism underlying ROXY19-TPL module mediated gene repression, DNA methylation and histone deacetylation inhibitors were applied to assess the involvement of epigenetic modifications in the silencing of detoxification pathway genes in ROXY19OE plants. Promoter regions of some ROXY19 repressed genes were not methylated in wild-type/Col-0, and the methylation status were not altered in ROXY19OE. Furthermore, we investigated the role of epigenetic modifications in the antagonistic interplay between ethylene/jasmonic acid (ET/JA) and salicylic acid (SA) signaling pathways, which were supposed to be regulated by ROXY19.

Sex-Specific Impact of Fkbp5 on Hippocampal Response to Acute Alcohol Injection: Involvement in Alterations of Metabolism-Related Pathways.

High levels of alcohol intake alter brain gene expression and can produce long-lasting effects. FK506-binding protein 51 (FKBP51) encoded by Fkbp5 is a physical and cellular stress response gene and has been associated with alcohol consumption and withdrawal severity. Fkbp5 has been previously linked to neurite outgrowth and hippocampal morphology, sex differences in stress response, and epigenetic modification. Presently, primary cultured Fkbp5 KO and WT mouse neurons were examined for neurite outgrowth and mitochondrial signal with and without alcohol. We found neurite specification differences between KO and WT; particularly, mesh-like morphology was observed after alcohol treatment and confirmed higher MitoTracker signal in cultured neurons of Fkbp5 KO compared to WT at both naive and alcohol-treated conditions. Brain regions that express FKBP51 protein were identified, and hippocampus was confirmed to possess a high level of expression. RNA-seq profiling was performed using the hippocampus of naïve or alcohol-injected (2 mg EtOH/Kg) male and female Fkbp5 KO and WT mice. Differentially expressed genes (DEGs) were identified between Fkbp5 KO and WT at baseline and following alcohol treatment, with female comparisons possessing a higher number of DEGs than male comparisons. Pathway analysis suggested that genes affecting calcium signaling, lipid metabolism, and axon guidance were differentially expressed at naïve condition between KO and WT. Alcohol treatment significantly affected pathways and enzymes involved in biosynthesis (Keto, serine, and glycine) and signaling (dopamine and insulin receptor), and neuroprotective role. Functions related to cell morphology, cell-to-cell signaling, lipid metabolism, injury response, and post-translational modification were significantly altered due to alcohol. In summary, Fkbp5 plays a critical role in the response to acute alcohol treatment by altering metabolism and signaling-related genes.

Genomic Analysis of a Community-Acquired Methicillin-Resistant Staphylococcus aureus Sequence Type 1 Associated with Caprine Mastitis.

This study aimed to investigate the genomic and epidemiological features of a methicillin-resistant Staphylococcus aureus sequence type 1 (MRSA ST1) strain associated with caprine subclinical mastitis. An S. aureus strain was isolated from goat's milk with subclinical mastitis in Paraiba, Northeastern Brazil, by means of aseptic procedures and tested for antimicrobial susceptibility using the disk-diffusion method. Whole genome sequencing was performed using the Illumina MiSeq platform. After genome assembly and annotation, in silico analyses, including multilocus sequence typing (MLST), antimicrobial resistance and stress-response genes, virulence factors, and plasmids detection were performed. A comparative SNP-based phylogenetic analysis was performed using publicly available MRSA genomes. The strain showed phenotypic resistance to cefoxitin, penicillin, and tetracycline and was identified as sequence type 1 (ST1) and spa type 128 (t128). It harbored the SCCmec type IVa (2B), as well as the lukF-PV and lukS-PV genes. The strain was phylogenetically related to six community-acquired MRSA isolates (CA-MRSA) strains associated with human clinical disease in North America, Europe, and Australia. This is the first report of a CA-MRSA strain associated with milk in the Americas. The structural and epidemiologic features reported in the MRSA ST1 carrying a mecA-SCCmec type IVa suggest highly complex mechanisms of horizontal gene transfer in MRSA. The SNP-based phylogenetic analysis suggests a zooanthroponotic transmission, i.e., a strain of human origin.