Search Results (48)

Asian soybean rust (ASR), caused by Phakopsora pachyrhizi (Syd.), poses a serious threat to global soybean production. The main approach to managing this disease has been through repeated fungicide applications which have reduced efficacy due to fungicide resistance. Recently, spray-induced gene silencing (SIGS) through exogenous application of double-stranded RNA (dsRNA) has emerged as a promising approach for plant disease management. In the present study, twelve different dsRNAs targeting genes important for P. pachyrhizi urediniospore germination, infection of the host plant or resistant to commonly used fungicides were produced in Escherichia coli on a large scale. Nine of these dsRNAs significantly reduced ASR severity (by 24.0% to 81.1%) and fungal biomass (50.5% to 83.1%) compared to the control when applied as a foliar spray in our growth chamber studies. Three of the most effective dsRNAs targeting an acyltransferase (ACE), cytochrome B (CYTB1) and a reductase (S12) also significantly reduced disease severity (78.2 to 82.3%) and fungal growth (79.8 to 85.4%) compared to the control in the greenhouse studies. Further investigation of the P. pachryrhizi urediniospore germination and hyphal growth in the presence of these dsRNAs in vitro revealed these dsRNAs reduced the spore germination rate from 72.1% to 0.0–26.6% at 4.5 h and hyphal growth from 254.0 µm to 2.7–40.5 µm at 9 h, with dsRNA targeting the S12 gene being the most effective. These results highlight the potential of SIGS using selected dsRNAs as a sustainable strategy for managing ASR through suppressing urediniospore germination and hyphal growth. Full article

Synthetic cathinones such as 3,4-methylenedioxypyrovalerone (MDPV) are potent psychostimulants with high abuse potential, yet their systemic toxicity and neurobehavioral effects remain poorly characterized during early development. Using Danio rerio (zebrafish) embryos and larvae, we performed an integrated assessment of the cardiotoxic, behavioral, and molecular effects of MDPV. Acute exposure of 3 days post-fertilization (dpf) embryos produced a marked, concentration-dependent bradycardia and atrioventricular (AV) conduction block, leading to reduced ventricular activity and complete AV dissociation at the highest concentrations (EC₅₀ = 228 µM). Quantitative analysis of ventricular motion revealed a significant decrease in cardiac output (CO) at all tested concentrations and a reduction in ejection fraction (EF) only at 480 µM, while fractional shortening (FS) and stroke volume (SV) remained unchanged, indicating predominant chronotropic and conduction effects with secondary contractile impairment. In 5 dpf larvae, MDPV caused a sustained, concentration-dependent decrease in basal locomotor activity (EC₅₀ = 2.51 µM) but did not affect prepulse inhibition (PPI) of the acoustic startle response (ASR), unlike dextroamphetamine, which enhanced PPI via dopaminergic D₂ receptor activation. Short-term (2 h) exposure of 3 dpf embryos to 0.4–400 µM MDPV induced transcriptional changes in dopaminergic and stress-responsive genes, whereas expression of major repolarizing potassium channel genes (kcnh6a and kcnq1) remained unaltered. Collectively, these results demonstrate that MDPV exerts potent negative chronotropic effects likely through direct functional interference with cardiac repolarization, while neurobehavioral effects occur at concentrations nearly two orders of magnitude lower than cardiotoxic thresholds, supporting zebrafish as a predictive model for the integrative assessment of psychostimulant toxicity. Full article

Background and Objectives: The dopamine D2 receptor (DRD2) plays a central role in fronto-striatal circuits regulating cognitive control and reward processing. The rs1076560 polymorphism alters receptor isoform expression, potentially modifying impulsivity and vulnerability to stimulant use disorders. We examined gene–environment interactions between rs1076560 and stimulant dependence in relation to impulsivity, ADHD traits, and hedonic capacity. Methods: A total of 517 men (235 stimulant-dependent, 282 controls) completed the Barratt Impulsiveness Scale (BIS-11), Adult ADHD Self-Report Scale (ASRS v1.1), and Snaith–Hamilton Pleasure Scale (SHAPS). Genotyping for rs1076560 was performed using real-time PCR, and two-way ANOVAs tested genotype-by-group effects. Results: Significant genotype-by-group interactions were observed across all BIS-11 subscales and ASRS scores. In the stimulant-dependent group, C/C homozygotes showed the highest levels of attentional impulsivity and attentional dysregulation compared to both A/C and C/C controls. In contrast, within the control group, A/A homozygotes demonstrated higher motor impulsivity, non-planning impulsivity, and BIS-11 total scores than C/C controls. No significant main effects or interactions were found for SHAPS scores. Conclusions: DRD2 rs1076560 moderates impulsivity-related traits through dopaminergic pathways relevant to executive dysfunction in stimulant use disorders. These findings highlight a neurobiological mechanism of addiction vulnerability and may inform precision approaches in neurology and psychiatry. Full article

Deployment of resistant barley cultivars is the most cost-effective and environmentally responsible strategy to manage barley leaf rust caused by Puccinia hordei. Gene predictions based on screening of germplasm with an array of well-characterised pathotypes and application of molecular markers serve as a pivotal step for identification, characterisation, and deploying resistance in breeding programmes. We evaluated 77 barley genotypes from 17 countries using an array of diverse P. hordei pathotypes and molecular markers to predict resistance gene identities. Evaluation and resistance analysis of the panel determined four known all-stage resistance (ASR) genes—Rph2, Rph3, Rph9.am, and Rph25 present individually or in combination, with Rph3 being the most common (33% of entries) and Rph2 the second most frequent (9%). Three entries, CG55, CG56, and CG57, exhibited low infection to all tested pathotypes and were negative for markers associated with Rph7, Rph15, and Rph28, potentially carrying novel uncharacterised resistance. In addition to ASR, our studies demonstrated that the core panel had a high prevalence of adult plant resistance (APR) to P. hordei, occurring in ~83% of entries. By employing markers linked to APR, we were able to partition known APR with Rph24 found in the most lines (60%), followed by Rph23 (17%), Rph20 (14%), and uncharacterised (9%) either individually or in combination. The resistance sources identified in this study can be effectively utilised and combined by breeding programmes to diversify their resistance gene pool. Our study also revealed the virulence and avirulence profiles of 12 Australian P. hordei pts to catalogued Rph genes, providing pathologists and breeders with insights into combining genes relevant to their breeding regions and pathogen shifts. Full article

Double-petal ornamental pomegranate presents for its enhanced ornamental value. Thus, cultivation techniques that promote petaloidy while modulating related gene expression are desired. To screen out the efficient treatments of plant growth regulator and key genes that enhance petaloidy, this study treated the flower buds of double- and single-petal ornamental pomegranate varieties with different concentrations of plant growth regulators naphthaleneacetic acid (NAA), methyl jasmonate (MeJA), abscisic acid (ABA), and ethephon (ETH) and quantified the number of petalized stamens (NOPSs) and the number of petals (NOPs) in both varieties. Furthermore, we investigated the expression levels of the genes flavin-containing monooxygenase (YUC), IAA-amino acid hydrolase (ILR1),indole-3-acetic acid-amido synthetase (GH3.17), auxin transporter (LAX2), auxin response factor (ARF), auxin-induced in root cultures protein (AIR12), jasmonic acid-amido synthetase (JAR1), and ABA stress ripening-induced protein (ASR) under the different treatments and analyzed their role in regulating relevant phenotypic traits. Plant growth regulator experiments demonstrated that NAA (10 mg/L) significantly increased the number of petalized stamens (NOPSs) and petals (NOPs), MeJA (100 mg/L) significantly increased the number of petalized stamens, while neither ABA nor ETH induced this morphological shift. qRT-PCR analysis confirmed that NAA upregulated ILR1, LAX2, ARF, and JAR1 in the stamens of single-petal flowers (StSi) and double-petal flowers (StDo) and petals of single-petal flowers (PeSi) and double-petal flowers (PeDo), with their expression levels strongly positively correlated with NOPS in both single- and double-petal flowers and NOP in double-petal flowers. MeJA upregulated ILR1, GH3.17, LAX2, ARF, and JAR1 in StDo and PeDo and was strongly positively correlated with NOPS and NOP in double-petal flowers. Consequently, NAA (10 mg/L) and MeJA (100 mg/L) were efficient treatments, and ILR1, GH3.17, LAX2, ARF, and JAR1 were identified as key genes in NAA- and MeJA-mediated petaloidy in ornamental pomegranates. Our results provide theoretical support for identifying the formation mechanism and improving industrial cultivation techniques for double-petal pomegranates. Full article

Background/Objectives: Late embryogenesis abundant (LEA) proteins regulate stress responses and contribute significantly to plant stress tolerance. As a model species for stress resistance studies, foxtail millet (Setaria italica) lacks comprehensive characterization of its LEA gene family. This study aimed to comprehensively identify SiLEA genes in foxtail millet and elucidate their functional roles and tissue-specific expression patterns. Methods: Genome-wide identification of SiLEA genes was conducted, followed by phylogenetic reconstruction, cis-acting element analysis of promoters, synteny analysis, and expression profiling. Results: Ninety-four SiLEA genes were identified and classified into nine structurally distinct subfamilies, which are unevenly distributed across all nine chromosomes. Phylogenetic analysis showed closer clustering of SiLEA genes with sorghum and rice orthologs than with Arabidopsis thaliana AtLEA genes. Synteny analysis indicated the LEA gene family expansion through tandem and segmental duplication. Promoter cis-element analysis linked SiLEA genes to plant growth regulation, stress responses, and hormone signaling. Transcriptome analysis revealed tissue-specific expression patterns among SiLEA members, while RT-qPCR verified ABA-induced transcriptional regulation of SiLEA genes. Conclusions: This study identified 94 SiLEA genes grouped into nine subfamilies with distinct spatial expression profiles. ABA treatment notably upregulated SiASR-2, SiASR-5, and SiASR-6 in both shoots and roots. Full article

Acrylamide (ACR) is a potent neurotoxicant that disrupts cellular redox homeostasis by depleting reduced glutathione (GSH) and inducing oxidative stress. Despite its well-characterized mechanism, no effective treatments for ACR-induced neurotoxicity currently exist. This study evaluates the therapeutic efficacy of N-acetylcysteine-amide (AD4), a blood–brain barrier (BBB)-permeable derivative of N-acetylcysteine, in a novel severe acute ACR neurotoxicity model in adult zebrafish. Adult zebrafish received a single intraperitoneal (i.p.) injection of ACR (800 μg/g), followed by AD4 (400 μg/g i.p.) or PBS 24 h later. ACR exposure reduced brain GSH levels by 51% reduction at 48 h, an effect fully reversed by AD4 treatment. Behavioral analyses showed that AD4 rescued ACR-induced deficits in short-term habituation of the acoustic startle response (ASR). Surprisingly, ACR exposure did not alter the neurochemical profile of key neurotransmitters or the expression of genes related to redox homeostasis, synaptic vesicle recycling, regeneration, or myelination. These results demonstrate AD4’s neuroprotective effects against acute ACR-induced brain toxicity, highlighting its therapeutic potential and validating adult zebrafish as a translational model for studying neurotoxic mechanisms and neuroprotective interventions. Full article

Abscisic acid (ABA)-stress-ripening, or ABA-, stress-, and ripening-induced (ASR) proteins play an important role in responses to environmental stimuli. A total of ten barley HvASRs were identified in this study, which were unevenly distributed on three chromosomes. ASRs from barley, wheat, Brachypodium distachyon, rice, maize, foxtail millet, and tomato were classified into two distinct clusters based on phylogenetic analysis. Notably, ASRs from Poaceae were evenly distributed between these two clusters. HvASRs contained a typical ABA/WDS domain, and exhibited similar motif arrangements. Two gene pairs of tandem duplicates (HvASR4/5/6/7 and HvASR8/9) were identified among HvASRs. Cis-acting elements involved in hormone and stress responses, including ABRE, MYB, ARE, and STRE, were consistently identified in the promoters of HvASRs. The expression of HvASRs was substantially influenced by salt, osmotic, and ABA treatments in the roots and leaves of barley seedlings. HvASR2 acts as a transcriptional repressor, whereas HvASR3 serves as a transcriptional activator. These results enhance our understanding of the HvASR family and provide a foundation for further functional characterization. Full article

Parkinson’s disease (PD), the second most common neurodegenerative disorder, is characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta, leading to motor and non-motor symptoms. The neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) has been extensively used in different animal species to develop chemical models of PD. This study aimed to evaluate the effects of acute exposure to MPTP (3 × 150 mg/kg, intraperitoneally) on adult zebrafish by assessing the neurochemical, transcriptional, and motor changes associated with PD pathogenesis. MPTP treatment resulted in a significant decrease in brain catecholamines, including dopamine, norepinephrine, and normetanephrine. Additionally, a trend towards decreased levels of dopamine precursors (tyrosine and L-DOPA) and degradation products (3-MT and DOPAC) was also observed, although these changes were not statistically significant. Gene expression analysis showed the downregulation of dbh, while the expression of other genes involved in catecholamine metabolism (th1, th2, mao, comtb) and transport (slc6a3 and slc18a2) remained unaltered, suggesting a lack of dopaminergic neuron degeneration. Behavioral assessments revealed that MPTP-exposed zebrafish exhibited reduced motor activity, consistent with the observed decrease in dopamine levels. In contrast, the kinematic parameters of sharp turning were unaffected. A significant impairment in the sensorimotor gating of the ASR was detected in the MPTP-treated fish, consistent with psychosis. Despite dopamine depletion and behavioral impairments, the absence of neurodegeneration and some hallmark PD motor symptoms suggests limitations in the validity of this model for fully recapitulating PD pathology. Further studies are needed to refine the use of MPTP in zebrafish PD models. Full article

Peanut (Arachis hypogaea L.) is one of the most important oil and food legume crops worldwide. ASR (abscisic acid, stress, ripening) plays extremely important roles in plant growth and development, fruit ripening, pollen development, and stress. Here, six ASR genes were identified in peanut. Structural and conserved motif analyses were performed to identify common ABA/WDS structural domains. The vast majority of ASR genes encoded acidic proteins, all of which are hydrophilic proteins and localized on mitochondria and nucleus, respectively. The cis-element analysis revealed that some cis-regulatory elements were related to peanut growth and development, hormone, and stress response. Under normal growth conditions, AhASR4 and AhASR5 were expressed in all tissues of peanut plants. Quantitative real-time PCR (qRT-PCR) results indicated that peanut ASR genes exhibited complex expression patterns in response to abiotic stress. Notably, under drought and cadmium (Cd) stress, the expression levels of AhASR4 and AhASR5 were significantly upregulated, suggesting that these genes may play a crucial role in the peanut plant’s resistance to such stressors. These results provide a theoretical basis for studying the evolution, expression, and function of the peanut ASR gene family and will provide valuable information in the identification and screening of genes for peanut stress tolerance breeding. Full article

Abiotic and biotic stress factors seriously affect plant growth and development. The process of plant response to abiotic stress involves the synergistic action of multiple resistance genes. The ASR (Abscisic acid stress-ripening) gene is a plant-specific transcription factor that plays a central role in regulating plant senescence, fruit ripening, and response to abiotic stress. ASR family members are highly conserved in plant evolution and contain ABA/WBS domains. ASR was first identified and characterized in tomatoes (Solanum lycopersicum L.). Subsequently, the ASR gene has been reported in many plant species, extending from gymnosperms to monocots and dicots, but lacks orthologues in Arabidopsis (Arabidopsis thaliana). The promoter regions of ASR genes in most species contain light-responsive elements, phytohormone-responsive elements, and abiotic stress-responsive elements. In addition, ASR genes can respond to biotic stresses via regulating the expression of defense genes in various plants. This review comprehensively summarizes the evolutionary history, gene and protein structures, and functions of the ASR gene family members in plant responses to salt stress, low temperature stress, pathogen stress, drought stress, and metal ions, which will provide valuable references for breeding high-yielding and stress-resistant plant varieties. Full article

Clostridium perfringens is the main pathogen of chicken necrotic enteritis (NE) causing huge economic losses in the poultry industry. Although dietary secondary bile acid deoxycholic acid (DCA) reduced chicken NE, the accumulation of conjugated tauro-DCA (TDCA) raised concerns regarding DCA efficacy. In this study, we aimed to deconjugate TDCA by bile salt hydrolase (BSH) to increase DCA efficacy against the NE pathogen C. perfringens. Assays were conducted to evaluate the inhibition of C. perfringens growth, hydrogen sulfide (H₂S) production, and virulence gene expression by TDCA and DCA. BSH activity and sequence alignment were conducted to select the bsh gene for cloning. The bsh gene from Bifidobacterium longum was PCR-amplified and cloned into plasmids pET-28a (pET-BSH) and pDR111 (pDR-BSH) for expressing the BSH protein in E. coli BL21 and Bacillus subtilis 168 (B-sub-BSH), respectively. His-tag-purified BSH from BL21 cells was evaluated by SDS-PAGE, Coomassie blue staining, and a Western blot (WB) assays. Secretory BSH from B. subtilis was analyzed by a Dot-Blot. B-sub-BSH was evaluated for the inhibition of C. perfringens growth. C. perfringens growth reached 7.8 log10 CFU/mL after 24 h culture. C. perfringens growth was at 8 vs. 7.4, 7.8 vs. 2.6 and 6 vs. 0 log10 CFU/mL in 0.2, 0.5, and 1 mM TDCA vs. DCA, respectively. Compared to TDCA, DCA reduced C. perfringens H₂S production and the virulence gene expression of asrA1, netB, colA, and virT. BSH activity was observed in Lactobacillus johnsonii and B. longum under anaerobe but not L. johnsonii under 10% CO₂ air. After the sequence alignment of bsh from ten bacteria, bsh from B. longum was selected, cloned into pET-BSH, and sequenced at 951 bp. After pET-BSH was transformed in BL21, BSH expression was assessed around 35 kDa using Coomassie staining and verified for His-tag using WB. After the subcloned bsh and amylase signal peptide sequence was inserted into pDR-BSH, B. subtilis was transformed and named B-sub-BSH. The transformation was evaluated using PCR with B. subtilis around 3 kb and B-sub-BSH around 5 kb. Secretory BSH expressed from B-sub-BSH was determined for His-tag using Dot-Blot. Importantly, C. perfringens growth was reduced greater than 59% log10 CFU/mL in the B-sub-BSH media precultured with 1 vs. 0 mM TDCA. In conclusion, TDCA was less potent than DCA against C. perfringens virulence, and recombinant secretory BSH from B-sub-BSH reduced C. perfringens growth, suggesting a new potential intervention against the pathogen-induced chicken NE. Full article

Although 14-3-3 proteins have been implicated in plant growth, development, and stress response, their roles in pepper immunity against R. solanacearum remain poorly understood. In this study, a 14-3-3-encoding gene in pepper, Ca16R, was found to be upregulated by R. solanacearum inoculation (RSI), its silencing significantly reduced the resistance of pepper plants to RSI, and its overexpression significantly enhanced the resistance of Nicotiana benthamiana to RSI. Consistently, its transient overexpression in pepper leaves triggered HR cell death, indicating that it acts positively in pepper immunity against RSI, and it was further found to act positively in pepper immunity against RSI by promoting SA but repressing JA signaling. Ca16R was also found to interact with CaASR1, originally using pull-down combined with a spectrum assay, and then confirmed using bimolecular fluorescence complementation (BiFC) and a pull-down assay. Furthermore, we found that CaASR1 transient overexpression induced HR cell death and SA-dependent immunity while repressing JA signaling, although this induction and repression was blocked by Ca16R silencing. All these data indicate that Ca16R acts positively in pepper immunity against RSI by interacting with CaASR1, thereby promoting SA-mediated immunity while repressing JA signaling. These results provide new insight into mechanisms underlying pepper immunity against RSI. Full article

Tetragonia tetragonoides (Pall.) Kuntze (Aizoaceae, 2n = 2x = 32), a vegetable used for both food and medicine, is a halophyte that is widely distributed in the coastal areas of the tropics and subtropics. Saline–alkaline soils and drought stress are two major abiotic stressors that significantly affect the distribution of tropical coastal plants. Abscisic acid-, stress-, and ripening-induced (ASR) proteins belong to a family of plant-specific, small, and hydrophilic proteins with important roles in plant development, growth, and abiotic stress responses. Here, we characterized the ASR gene family from T. tetragonoides, which contained 13 paralogous genes, and divided TtASRs into two subfamilies based on the phylogenetic tree. The TtASR genes were located on two chromosomes, and segmental duplication events were illustrated as the main duplication method. Additionally, the expression levels of TtASRs were induced by multiple abiotic stressors, indicating that this gene family could participate widely in the response to stress. Furthermore, several TtASR genes were cloned and functionally identified using a yeast expression system. Our results indicate that TtASRs play important roles in T. tetragonoides’ responses to saline–alkaline soils and drought stress. These findings not only increase our understanding of the role ASRs play in mediating halophyte adaptation to extreme environments but also improve our knowledge of plant ASR protein evolution. Full article

Asian soybean rust (ASR), caused by Phakopsora pachyrhizi, is one of the most destructive foliar diseases that affect soybeans. Developing resistant cultivars is the most cost-effective, environmentally friendly, and easy strategy for controlling the disease. However, the current understanding of the mechanisms underlying soybean resistance to P. pachyrhizi remains limited, which poses a significant challenge in devising effective control strategies. In this study, comparative transcriptomic profiling using one resistant genotype and one susceptible genotype was performed under infected and control conditions to understand the regulatory network operating between soybean and P. pachyrhizi. RNA-Seq analysis identified a total of 6540 differentially expressed genes (DEGs), which were shared by all four genotypes. The DEGs are involved in defense responses, stress responses, stimulus responses, flavonoid metabolism, and biosynthesis after infection with P. pachyrhizi. A total of 25,377 genes were divided into 33 modules using weighted gene co-expression network analysis (WGCNA). Two modules were significantly associated with pathogen defense. The DEGs were mainly enriched in RNA processing, plant-type hypersensitive response, negative regulation of cell growth, and a programmed cell death process. In conclusion, these results will provide an important resource for mining resistant genes to P. pachyrhizi infection and valuable resources to potentially pyramid quantitative resistance loci for improving soybean germplasm. Full article