Stress-responsive Genes Research Articles

Adaptive evolution of stress response genes in parasites aligns with host niche diversity

BackgroundStress responses are key the survival of parasites and, consequently, also the evolutionary success of these organisms. Despite this importance, our understanding of the evolution of molecular pathways dealing with environmental stressors in parasitic animals remains limited. Here, we tested the link between adaptive evolution of parasite stress response genes and their ecological diversity and species richness. We comparatively investigated antioxidant, heat shock, osmoregulatory, and behaviour-related genes (foraging) in two model parasitic flatworm lineages with contrasting ecological diversity, Cichlidogyrus and Kapentagyrus (Platyhelminthes: Monopisthocotyla), through whole-genome sequencing of 11 species followed by in silico exon bait capture as well as phylogenetic and codon analyses.ResultsWe assembled the sequences of 48 stress-related genes and report the first foraging (For) gene orthologs in flatworms. We found duplications of heat shock (Hsp) and oxidative stress genes in Cichlidogyrus compared to Kapentagyrus. We also observed positive selection patterns in genes related to mitochondrial protein import (Hsp) and behaviour (For) in species of Cichlidogyrus infecting East African cichlids—a host lineage under adaptive radiation. These patterns are consistent with a potential adaptation linked to a co-radiation of these parasites and their hosts. Additionally, the absence of cytochrome P450 and kappa and sigma-class glutathione S-transferases in monogenean flatworms is reported, genes considered essential for metazoan life.ConclusionsThis study potentially identifies the first molecular function linked to a flatworm radiation. Furthermore, the observed gene duplications and positive selection indicate the potentially important role of stress responses for the ecological adaptation of parasite species.

Enhancing Soybean Salt Tolerance with GSNO and Silicon: A Comprehensive Physiological, Biochemical, and Genetic Study

Soil salinity is a major global challenge affecting agricultural productivity and food security. This study explores innovative strategies to improve salt tolerance in soybean (Glycine max), a crucial crop in the global food supply. This study investigates the synergistic effects of S-nitroso glutathione (GSNO) and silicon on enhancing salt tolerance in soybean (Glycine max). Two soybean cultivars, Seonpung (salt-tolerant) and Cheongja (salt-sensitive), were analyzed for various physiological, biochemical, and genetic traits under salt stress. The results showed that the combined GSNO and Si treatment significantly improved several key traits, including plant height, relative water content, root development, nodule numbers, chlorophyll content, and stomatal aperture, under both control and salt stress conditions. Additionally, this treatment optimized ion homeostasis by enhancing the Na/K ratio and Ca content, while reducing damage markers such as electrolyte leakage, malondialdehyde, and hydrogen peroxide. The stress-responsive compounds, including proline, ascorbate peroxidase, and water-soluble proteins, were elevated under stress conditions, indicating improved tolerance. Gene expression analysis revealed significant upregulation of genes such as GmNHX1, GmSOS2, and GmAKT1, associated with salt stress response, while GmNIP2.1, GmNIP2.2, and GmLBR were downregulated in both varieties. Notably, the salt-sensitive variety Cheongja exhibited higher electrolyte leakage and oxidative damage compared to the salt-tolerant Seonpung. These findings suggest that the combination of GSNO and silicon enhances salt tolerance in soybean by improving physiological resilience, ion homeostasis, and stress-responsive gene expression.

How the Ectopic Expression of the Barley F-Box Gene HvFBX158 Enhances Drought Resistance in Arabidopsis thaliana.

In this study, the drought-responsive gene HvFBX158 from barley was transferred to Arabidopsis thaliana, and overexpression lines were obtained. The phenotypic characteristics of the transgenic plants, along with physiological indicators and transcription level changes of stress-related genes, were determined under drought treatment. Under drought stress, transgenic plants overexpressing HvFBX158 exhibited enhanced drought tolerance and longer root lengths compared to wild-type plants. Additionally, malondialdehyde and hydrogen peroxide contents were significantly lower in transgenic lines, while superoxide dismutase activity was elevated. Quantitative RT-PCR showed that the expression levels of drought and stress response genes, including AtP5CS, AtDREB2A, AtGSH1, AtHSP17.8, and AtSOD, were significantly upregulated. Transcriptome analysis further confirmed that HvFBX158 regulated multiple stress tolerance pathways. In summary, the overexpression of the HvFBX158 gene enhanced drought tolerance in Arabidopsis thaliana by regulating multiple stress response pathways. This study provides a practical basis for improving drought-resistant barley varieties and lays a foundation for subsequent research on F-box family genes for stress resistance in barley.

The Effect of a Secondary Stressor on the Morphology and Membrane Structure of an Already Challenged Maternal and Foetal Red Blood Cell Population.

The red blood cell (RBC) membrane is unique and crucial for maintaining structural-functional relationships. Maternal smoking induces significant changes in the morphological, rheological, and functional parameters of both maternal and foetal RBCs, mainly due to the continuous generation of the free radicals. The major aim of this study was to follow the consequences of a secondary stressor, like fungal infection, on the already compromised RBC populations. The impact of Candida infection, a growing health concern, was investigated on four blood sample groups: mothers and their neonates originating from non-smoking versus smoking populations. Here, we searched for phenotypical and molecular markers that precisely reflected the effect of Candida infection on the RBC membrane; this included the level of hemolysis, appearance of morphological variants, formation of the lipid peroxidation marker 4-hydroxyl-nonenal, arrangement of the Band 3 molecules and activation of the Caspase 3. In most of the examined cases, the fungal infection increased the adverse symptoms induced by smoking, indicating a general stress response, likely due to an altered redox state of the cells. However, we were able to identify an atypical phenotype (clustered populations with shrinkage and membrane blebbing) in both the non-smoking and smoking populations, which might be a unique marker for Candida spp. infection.

Flavonoids as key players in cold tolerance: molecular insights and applications in horticultural crops

Abstract Cold stress profoundly affects the growth, development, and productivity of horticultural crops. Among the diverse strategies plants employ to mitigate the adverse effects of cold stress, flavonoids have emerged as pivotal components in enhancing plant resilience. This review was written to systematically highlight the critical role of flavonoids in plant cold tolerance, aiming to address the increasing need for sustainable horticultural practices under climate stress. We provide a comprehensive overview of the role of flavonoids in the cold tolerance of horticultural crops, emphasizing their biosynthesis pathways, molecular mechanisms, and regulatory aspects under cold stress conditions. We discuss how flavonoids act as antioxidants, scavenging reactive oxygen species (ROS) generated during cold stress, and how they regulate gene expression by modulating stress-responsive genes and pathways. Additionally, we explore the application of flavonoids in enhancing cold tolerance through genetic engineering and breeding strategies, offering insights into practical interventions for improving crop resilience. Despite significant advances, a research gap remains in understanding the precise molecular mechanisms by which specific flavonoids confer cold resistance, especially across different crop species. By addressing current knowledge gaps, proposing future research directions, and highlighting implications for sustainable horticulture, we aim to advance strategies to enhance cold tolerance in horticultural crops.

Transcriptomic and Microbiome Analyses of copepod Apocyclops royi in Response to an AHPND-causing strain of Vibrio parahaemolyticus

Copepods are small crustaceans that live in microorganism-rich aquatic environments and provide a key supply of live food for fish and shellfish larviculture. To better understand the host-pathogen interaction between the copepod and Vibrio parahaemolyticus causing acute hepatopancreatic necrosis disease (VPAHPND), the comparative transcriptome and microbiome analyses were conducted in copepod Apocyclops royi-TH following VPAHPND infection. Transcriptome analysis identified a total of 836 differentially expressed genes, with 275 upregulated and 561 downregulated genes. Subsequent analysis showed that a total of 37 differentially expressed genes were associated with the innate immune system, including 16 upregulated genes related to Toll-like receptor signaling pathway, antimicrobial peptides, and stress response genes, and 21 downregulated genes associated with immunological modulators, signaling molecules, and apoptosis-related proteins. Analysis of the copepod microbiome following VPAHPND infection showed that the microbes changed significantly after bacterial infection, with a reduced alpha diversity accompanied by the increased level of Proteobacteria and decreased levels of Bdellovibrionota, Bacteroidota, and Verrucomicrobiota. The population of Vibrio genera were increased significantly, while several other genera, including Denitromonas, Nitrosomonas, Blastopirellula, Fusibacter, Alteromonas, KI89A_clade, and Ruegeria, were decreased significantly after infection. These findings suggest that VPAHPND infection has a significant impact on the immune defense and the composition of the copepod microbiota.

Genome-wide identification and characterization of alfalfa-specific genes in drought stress tolerance.

Alfalfa (Medicago sativa L.) is a prominent and distinct species within the pasture germplasm innovation industry. However, drought poses a substantial constraint on the yield and distribution of alfalfa by adversely affecting its growth. Although lineage-specific genes are instrumental in modulating plant responses to stress, their role in mediating alfalfa's tolerance to drought stress has yet to be elucidated. In this study, a total of 199 alfalfa-specific genes (ASGs) and 3054 legume-specific genes (LSGs) were identified in alfalfa. Compared with evolutionarily conserved genes, ASGs have shorter sequence length and fewer or no intron. Many alfalfa ASGs can be induced by various abiotic stresses, and the capability of MsASG166 to enhance drought resistance has been substantiated through transgenic research in both yeast and Arabidopsis thaliana. The RNA-Seq and WGCNA analyses revealed that DREB2A and MADS are pivotal genes in the molecular mechanisms through which MsASG166 positively modulates plant drought resistance. This study marks the first identification of lineage-specific genes in alfalfa and an examination of the molecular roles of the MsASG166 gene in drought stress responses. The findings offer valuable genetic resources for the development of novel, genetically engineered alfalfa germplasm with enhanced drought tolerance.

Regulatory dynamics of Sch9 in response to cytosolic acidification: From spatial reconfiguration to cellular adaptation to stresses.

The regulation of cellular metabolism is crucial for cell survival, with Sch9 in Saccharomyces cerevisiae serving a key role as a substrate of TORC1. Sch9 localizes to the vacuolar membrane through binding to PI(3,5)P2, which is necessary for TORC1-dependent phosphorylation. This study demonstrates that cytosolic pH regulates Sch9 localization. Under stress conditions that induce cytosolic acidification, Sch9 detached from the vacuolar membrane. Invitro experiments confirmed that Sch9's affinity for PI(3,5)P2 is pH-dependent. This pH-dependent localization switch is essential for regulating the TORC1-Sch9 pathway. Impairment of the dissociation of Sch9 from the vacuolar membrane in response to cytosolic acidification resulted in the deficient induction of stress response gene expression and delayed the adaptive response to acetic acid stress. These findings indicate the importance of proper Sch9 localization for metabolic reprogramming and stress response in yeast cells.

The transcription factor YbdO attenuates the pathogenicity of avian pathogenic Escherichia coli by regulating oxidative stress response

Avian pathogenic Escherichia coli (APEC) is a significant pathogen infecting poultry that is responsible for high mortality, morbidity and severe economic losses to the poultry industry globally, posing a substantial risk to the health of poultry. APEC encounters reactive oxygen species (ROS) during the infection process and thus has evolved antioxidant defense mechanisms to protect against oxidative damage. The imbalance of ROS production and antioxidant defenses is known as oxidative stress, which results in oxidative damage to proteins, lipids and DNA, and even bacterial cell death. APEC uses transcription factors (TFs) to handle oxidative stress. While many TFs in E. coli have been well characterized, the mechanism of the YbdO TF on protecting against oxidative damage and regulating the virulence and pathogenicity of APEC has not been clarified. Here we focus on the regulatory mechanism of YbdO on the pathogenicity of APEC. The results from this study showed that YbdO attenuated the pathogenicity of APEC in chicks infection models by inhibiting the expression of virulence genes fepG and ycgV using quantitative real-time reverse transcription PCR (RT-qPCR) experiments. The electrophoretic mobility shift assays (EMSA) confirmed that YbdO specifically bound to the promoters of fepG and ycgV. Additionally, YbdO increases H2O2-induced oxidative damage to APEC via repressing the expression of oxidative stress response genes sodA, soxR, ahpC, ahpF, katG, and oxyR by binding to their promoter regions. The repression effect facilitates host immune response to eliminate APEC and to generate beneficial immune protection to the body, thereby indirectly attenuating the pathogenicity of APEC. These findings might provide further insights into the mechanism of oxidative damage to APEC and offer new perspectives for further studies on the prevention and control of APEC infections.

Decreased Hsp90 activity protects against TDP-43 neurotoxicity in a C. elegans model of amyotrophic lateral sclerosis.

Neuronal inclusions of hyperphosphorylated TDP-43 are hallmarks of disease for most patients with amyotrophic lateral sclerosis (ALS). Mutations in TARDBP, the gene coding for TDP-43, can cause some cases of familial inherited ALS (fALS), indicating dysfunction of TDP-43 drives disease. Aggregated, phosphorylated TDP-43 may contribute to disease phenotypes; alternatively, TDP-43 aggregation may be a protective cellular response sequestering toxic protein away from the rest of the cell. The heat shock responsive chaperone Hsp90 has been shown to interact with TDP-43 and stabilize its normal conformation; however, it is not known whether this interaction contributes to neurotoxicity in vivo. Using a C. elegans model of fALS mutant TDP-43 proteinopathy, we find that loss of function of HSP-90 protects against TDP-43 neurotoxicity and subsequent neurodegeneration in adult animals. This protection is accompanied by a decrease in both total and phosphorylated TDP-43 protein. We also find that hsp-90 mutation or inhibition upregulates key stress responsive heat shock pathway gene expression, including hsp-70 and hsp-16.1, and we demonstrate that normal levels of hsp-16.1 are required for hsp-90 mutation effects on TDP-43. We also observe that the neuroprotective effect due to HSP-90 dysfunction does not involve direct regulation of proteasome activity in C. elegans. Our data demonstrate for the first time that Hsp90 chaperone activity contributes to adverse outcomes in TDP-43 proteinopathies in vivo using a whole animal model of ALS.

Overexpression of an NF-YB gene family member, EaNF-YB2, enhances drought tolerance in sugarcane (Saccharum Spp. Hybrid).

Drought is one of main critical factors that limits sugarcane productivity and juice quality in tropical regions. The unprecedented changes in climate such as monsoon failure, increase in temperature and other factors warrant the need for development of stress tolerant cultivars to sustain sugar production. Plant Nuclear factor (NF-Y) is one of the major classes of transcription factors that have a major role in plant development and abiotic stress response. In our previous studies, we found that under drought conditions, the nuclear factor NF-YB2 was highly expressed in Erianthus arundinaceus, an abiotic stress tolerant wild genus of Saccharum species. In this study, the coding sequence of NF-YB2 gene was isolated from Erianthus arundinaceus and overexpressed in sugarcane to develop drought tolerant lines. RESULTS: EaNF-YB2 overexpressing sugarcane (OE) lines had higher relative water content, chlorophyll content and photosynthetic efficiency compared to non-transgenic (NT) control. In addition, overexpressing lines had higher activity of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR), and higher proline content, lower malondialdehyde (MDA) and peroxide (H2O2) contents. The expression studies revealed that EaNF-YB2 expression was significantly higher in OE lines than NT control under drought stress. The OE lines had an elevated expression of abiotic stress responsive genes such as BRICK, HSP 70, DREB2, EDH45, and LEA3. The morphological analysis revealed that OE lines exhibited less wilting than NT under drought conditions. This study provides insights into the role of the EaNF-YB2 gene in drought tolerance in sugarcane. Based on the findings of this study, the EaNF-YB2 gene can be potentially exploited to produce drought tolerant sugarcane cultivars to sustain sugarcane production under water deficit conditions.

Comparative Physiological and Transcriptomics Profiling Provides Integrated Insight into Melatonin Mediated Salt and Copper Stress Tolerance in Selenicereus undatus L.

Selenicereus undatus L., (pitaya) is an important tropical fruit crop, and faces significant challenges from soil salinity and heavy metal toxicity. This study explores the role of melatonin (M) in enhancing stress tolerance in pitaya against salinity (S) and copper (Cu) toxicity, both individually and in combination (SCu). SCu stress reduced plant biomass by ~54%, while melatonin application mitigated stress effects and increased plant growth by ~73.26% under SCuM compared to SCu treatment. Antioxidant activities were also modulated by stress. Transcriptomic analysis revealed 21 differentially expressed genes (DEGs) common across stress treatments and 13 DEGs specific to combined melatonin with stress treatments involved in stress signaling, secondary metabolite biosynthesis, and photosynthesis. A weighted gene co-expression network analysis (WGCNA) identified four gene modules (brown, dark green, dark grey, and grey) significantly associated with phenotypic traits. A protein-protein interaction (PPI) network analysis highlighted 14 hub genes per module, including GH3, JAZ, PAL, CCR, and POD, implicated in MAPK signaling, phenylpropanoid biosynthesis, and hormone signaling pathways. Integration of DESeq2 and WGCNA identified 12 key stress-responsive genes strongly correlated with phenotypic traits. This study provides insights into regulatory mechanisms underlying stress responses and highlights candidate genes for developing stress-resilient S. undatus through breeding programs.

Identification and Expression Analysis of Low-Temperature Stress Responsive MIKC-Type MADS-Box Gene Family in Wheat

Identification and Expression Analysis of Low-Temperature Stress Responsive MIKC-Type MADS-Box Gene Family in Wheat

The molecular framework balancing growth and defense in response to PEP-induced signals in Arabidopsis.

Elevated stress signaling compromises plant growth by suppressing proliferative and formative division in the meristem. Plant Elicitor Peptide (PEP), an endogenous danger signal triggered by biotic and abiotic stresses in Arabidopsis (Arabidopsis thaliana), suppresses proliferative division, alters xylem vessel organization, and disrupts cell-to-cell symplastic connections in roots. To gain insight into the dynamic molecular framework that modulates root development under elevated danger signals, we performed a time-course RNA-sequencing analysis of the root meristem after synthetic PEP1 treatment. Our analyses revealed that SALT TOLERANCE ZINC FINGER (STZ) and its homologs are a potential nexus between the stress response and proliferative cell cycle regulation. Through functional, phenotypic, and transcriptomic analyses, we observed that STZ differentially controls the cell cycle, cell differentiation, and stress response genes in various tissue layers of the root meristem. Moreover, we determined the STZ expression level critical for enabling the growth-defense tradeoff. These findings provide valuable information about the dynamic gene expression changes that occur upon perceiving danger signals in the root meristem and potential engineering strategies to generate stress-resilient plants.

In vitro resensitization of multidrug-resistant clinical isolates of Enterococcus faecium and E. faecalis through phage-antibiotic synergy.

Bacteriophages are an increasingly attractive option for the treatment of antibiotic-resistant infections, but their efficacy is difficult to discern due to the confounding effects of antibiotics. Phages are generally delivered in conjunction with antibiotics, and thus, when patients improve, it is unclear whether the phages, antibiotics, or both are responsible. This question is particularly relevant for enterococcus infections, as limited data suggest phages might restore antibiotic efficacy against resistant strains. Enterococci can develop high-level resistance to vancomycin, a primary treatment. We assessed clinical and laboratory isolates of Enterococcus faecium and Enterococcus faecalis to determine whether we could observe synergistic interactions between phages and antibiotics. We identified synergy between multiple phages and antibiotics including linezolid, ampicillin, and vancomycin. Notably, antibiotic susceptibility did not predict synergistic interactions with phages. Vancomycin-resistant isolates (n = 6) were eradicated by the vancomycin-phage combination as effectively as vancomycin-susceptible isolates (n = 2). Transcriptome analysis revealed significant gene expression changes under antibiotic-phage conditions, especially for linezolid and vancomycin, with upregulated genes involved in nucleotide and protein biosynthesis and downregulated stress response and prophage-related genes. While our results do not conclusively determine the mechanism of the observed synergistic interactions between antibiotics and phages, they do confirm and build upon previous research that observed these synergistic interactions. Our work highlights how using phages can restore the effectiveness of vancomycin against resistant isolates. This finding provides a promising, although unexpected, strategy for moving forward with phage treatments for vancomycin-resistant Enterococcus infections.

Knockdown of OsPHP1 Leads to Improved Yield Under Salinity and Drought in Rice via Regulating the Complex Set of TCS Members and Cytokinin Signalling.

Plant two-component system (TCS) is crucial for phytohormone signalling, stress response, and circadian rhythms, yet the precise role of most of the family members in rice remain poorly understood. In this study, we investigated the function of OsPHP1, a pseudo-histidine phosphotransfer protein in rice, using a functional genomics approach. OsPHP1 is localised in the nucleus and cytosol, and it exhibits strong interactions with all sensory histidine kinase proteins (OsHK1-6) and cytokinin catabolism genes. Our results demonstrate that OsPHP1 functions as a negative regulator of cytokinin signalling. Knockdown of OsPHP1 enhanced the expression of positive cytokinin signalling regulators, such as OsHKs and OsAHPs (authentic phosphotransfer proteins), while downregulating negative regulators, such as type-A response regulators (OsRRs) and cytokinin catabolism genes (CKXs). Furthermore, OsPHP1 negatively influences abiotic stress tolerance, as evidenced by the increased sensitivity of OsPHP1-OE (overexpression) lines to salinity and drought. In contrast, OsPHP1-KD (knockdown) lines showed enhanced stress resilience, with better photosynthesis, increased tiller and panicle production, higher spikelet fertility, and grain filling. The study demonstrates that OsPHP1 suppresses antioxidant and stress-responsive genes, exacerbating ion toxicity and reducing osmolyte accumulation, thereby impairing plant growth and yield under stress conditions. These findings highlight OsPHP1 as a critical modulator of plant responses to abiotic stress and suggest potential genetic targets for enhancing crop stress tolerance.

Molecular insights into salt tolerance in Dunaliella tertiolectainvolving two betaine aldehyde dehydrogenases.

Understanding salt tolerance mechanisms is crucial for addressing the global challenge of soil salinization and advancing sustainable agricultural practices. Dunaliella tertiolecta, thriving in up to 4.5M NaCl, is a model for studying salt tolerance mechanisms. Two betaine aldehyde dehydrogenase (BADH) genes were identified in D. tertiolecta, namely DtBADH1 and DtBADH2. The phylogenetic analysis revealed that DtBADH1 had similarity to Pseudomonas aeruginosa BADH, while DtBADH2 has high homology to aldehyde dehydrogenase from Chlorella sorokiniana. The 3D models of DtBADH1 and DtBADH2 docking with betaine aldehyde were performed to further validate their binding site, interactions binding the protein and its substrate as well as the conserved amino acids responsible for enzyme activity. We also conducted RNA interference of DtBADH1 and DtBADH2 in D. tertiolecta. Compared to the wild type D. tertiolecta, both BADH-RNAi D. tertiolecta had fewer cell numbers and relatively lower glycine betaine content under high salinity. The findings suggest that both DtBADH1 and DtBADH2 play a crucial role in betaine synthesis, indicating their potential involvement in salt tolerance mechanisms at the molecular level. Additionally, these results highlight D. tertiolecta as a promising candidate for identifying salt stress-responsive genes, which could be utilized for engineering algae or crops to enhance their ability to withstand salinity stress.

Genome-wide characterization of Solanum tuberosum UGT gene family and functional analysis of StUGT178 in salt tolerance

UDP-glycosyltransferases (UGTs) widely exist in plants and play essential roles in catalyzing the glycosylation reaction associated with metabolic processes. UGT gene family has been identified in many species to date. However, the comprehensive identification and systematic analysis have not been documented yet in the latest potato genome. In this study, a total of 295 UGT members (StUGT) were identified and found to be unevenly distributed on twelve chromosomes of potato. All StUGT genes were classified into 17 groups (A-P, R) and the UGT genes within the same groups have similar structural characterization. Tandem duplication was the major driving force for the StUGT gene expansion. The prediction of cis-acting elements showed that the development process, light, phytohormone, and abiotic stress-responsive elements generally existed in StUGT promoter regions. Analysis of spatial and temporal expression patterns demonstrated that StUGT genes were widely and differentially expressed in various tissues. Additionally, to investigate the salt stress-responsive genes, we analyzed the expression profiles of the StUGT genes under salt treatment. A total of 50 and 20 StUGT genes were continuously up- and down-regulated, respectively, implicating that these genes were involved in the regulation of salt tolerance. Among them, the StUGT178 gene, which was significantly induced by salt stress and contains salt-responsive element, was considered as one of the most relevant candidate genes. Transient transformation of the StUGT178 promoter in tobacco revealed that the transcriptional activation activity of the StUGT178 gene was strengthened under salt treatment. Furthermore, the heterologous expressions of the promoter and coding protein of the StUGT178 gene in Arabidopsis further demonstrated that the StUGT178 gene significantly responds to salt treatment, and enhanced salinity tolerance by regulating antioxidant enzyme activity and H2O2 accumulation. These results provide comprehensive information for a better understanding of the StUGT genes and offer a foundation for uncovering their function associated with salt stress in potato.

Cytochrome c levels link mitochondrial function to plant growth and stress responses through changes in SnRK1 pathway activity.

Energy is required for growth as well as for multiple cellular processes. During evolution, plants developed regulatory mechanisms to adapt energy consumption to metabolic reserves and cellular needs. Reduced growth is often observed under stress, leading to a growth-stress trade-off that governs plant performance under different conditions. In this work, we report that plants with reduced levels of the mitochondrial respiratory chain component cytochrome c (CYTc), required for electron transport coupled to oxidative phosphorylation and ATP production, show impaired growth and increased global expression of stress-responsive genes, similar to those observed after inhibiting the respiratory chain or the mitochondrial ATP synthase. CYTc-deficient plants also show activation of the SnRK1 pathway, which regulates growth, metabolism, and stress responses under carbon starvation conditions, even though their carbohydrate levels are not significantly different from wild-type. Notably, loss-of-function of the gene encoding the SnRK1α1 subunit restores the growth of CYTc-deficient plants, as well as autophagy, free amino acid and TOR pathway activity levels, which are affected in these plants. Moreover, increasing CYTc levels decreases SnRK1 pathway activation, reflected in reduced SnRK1α1 phosphorylation, with no changes in total SnRK1α1 protein levels. Under stress imposed by mannitol, the growth of CYTc-deficient plants is relatively less affected than that of wild-type plants, which is also related to the activation of the SnRK1 pathway. Our results indicate that SnRK1 function is affected by CYTc levels, thus providing a molecular link between mitochondrial function and plant growth under normal and stress conditions.

Exploring Drought Resistance Genes from the Roots of the Wheat Cultivar Yunhan1818.

The root is an important organ by which plants directly sense variation in soil moisture. The discovery of drought stress-responsive genes in roots is very important for the improvement of drought tolerance in wheat varieties via molecular approaches. In this study, transcriptome sequencing was conducted on the roots of drought-tolerant wheat cultivar YH1818 seedlings at 0, 2, and 7 days after treatment (DAT). Based on a weighted gene correlation network analysis of differentially expressed genes (DEGs), 14 coexpression modules were identified, of which five modules comprising 3107 DEGs were related to 2 or 7 DAT under drought stress conditions. A total of 223,357 single-nucleotide polymorphisms (SNPs) of these DEGs were retrieved from public databases. Using the R language package and GAPIT program, association analysis was performed between the 223,357 SNPs and the drought tolerance coefficient (DTC) values of six drought resistance-related traits in 114 wheat germplasms. The results revealed that 18 high-confidence SNPs of 10 DEGs, including TaPK, TaRFP, TaMCO, TaPOD, TaC3H-ZF, TaGRP, TaDHODH, TaPPDK, TaLectin, and TaARF7-A, were associated with drought tolerance. The RT-qPCR results confirmed that these genes were significantly upregulated by drought stress at 7 DAT. Among them, TaARF7-A contained three DTC-related SNPs, which presented two haplotypes in the tested wheat germplasms. YH1818 belongs to the Hap1 allele, which is involved in increased drought tolerance. This study revealed key modules and candidate genes for understanding the drought-stress response mechanism in wheat roots.