Role In Defense Research Articles

Characterization of the chitinase gene family in Saccharum reveals the disease resistance mechanism of ScChiVII1.

A chitinase gene ScChiVII1 which is involved in defense against pathogen stress was characterized in sugarcane. Chitinases, a subclass of pathogenesis-related proteins, catalyze chitin hydrolysis and play a key role in plant defense against chitin-containing pathogens. However, there is little research on disease resistance analysis of chitinase genes in sugarcane, and the systematic identification of their gene families has not been reported. In this study, 85 SsChi and 23 ShChi genes, which were divided into 6 groups, were identified from the wild sugarcane species Saccharum spontaneum and Saccharum hybrid cultivar R570, respectively. Transcriptome analysis and real-time quantitative PCR revealed that SsChi genes responded to smut pathogen stress. The chitinase crude extracted from the leaves of transgenic Nicotiana benthamiana plants overexpressing ScChiVII1 (a homologous gene of SsChi22a) inhibited the hyphal growth of Fusarium solani var. coeruleum and Sporisorium scitamineum. Notably, the chitinase and catalase activities and the jasmonic acid content in the leaves of ScChiVII1 transgenic N. benthamiana increased after inoculation with F solani var. coeruleum, but the salicylic acid, hydrogen peroxide, and malondialdehyde contents decreased. Comprehensive RNA sequencing of leaves before (0day) and after inoculation (2days) revealed that ScChiVII1 transgenic tobacco enhanced plant disease resistance by activating transcription factors and disease resistance-related signaling pathways, and modulating the expression of genes involved in the hypersensitive response and ethylene synthesis pathways. Taken together, this study provides comprehensive information on the chitinase gene family and offers potential genetic resources for disease resistance breeding in sugarcane.

The Role of the Complement System in Autoimmune Diseases and Therapeutic Targeting

The complement system, a critical component of the innate immune system, plays a dual role in immune defense and pathogenesis, particularly in autoimmune diseases. Comprising over 30 proteins, the complement system facilitates pathogen clearance, inflammation, and immune modulation. However, its dysregulation can lead to uncontrolled activation and contribute to the development and progression of various autoimmune disorders, including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), multiple sclerosis (MS), antiphospholipid syndrome (APS), and vasculitis. In these diseases, excessive complement activation triggers inflammation, immune cell recruitment, and tissue damage, exacerbating the autoimmune response. This review provides an in-depth analysis of the complement system’s role in autoimmune diseases, exploring how its three activation pathways—classical, lectin, and alternative—contribute to disease pathogenesis. It also discusses key complement proteins such as C3, C5, and the membrane attack complex (MAC) in promoting inflammatory responses in these conditions. Moreover, the review highlights recent advances in therapeutic strategies targeting the complement system, including the development of C5 inhibitors like eculizumab and C3 inhibitors, which show promise in treating complement-mediated autoimmune diseases. These therapies aim to reduce inflammation and tissue destruction, offering new approaches for managing autoimmune disorders. Understanding complement dysregulation is crucial for the development of more effective treatments in the future. Keywords: Complement system, Autoimmune diseases, Complement activation, Inflammation, Therapeutic targeting

Unravelling the ontogeny and tissue-specific expression profiles of immune-related genes in the near-threatened endemic catfish, Clarias dussumieri

Clarias dussumieri, an air breathing catfish endemic to the Western Ghats in India, is categorized as 'Near Threatened' by the IUCN. This species is of high regional consumer demand and is one of the prioritized candidate species for aquaculture diversification and conservation. Despite its ecological and commercial significance, comprehensive studies on its immune system are lacking. This study elucidates the ontogenetic development and tissue-specific (brain, anterior kidney, gill, spleen, muscle, liver, hindgut and skin) expression profiles of key immune-related genes in C. dussumieri. Larvae were sampled at various developmental stages post-fertilization, and tissues from adult fish were analyzed for expression patterns of genes associated with inflammation (IL-1β, TNF-α, iNOS), antimicrobial defense (LYS, HAMP), stress response (HSP70), complement system (C3), cell-mediated immunity (MHC-IIβ, CD4-1), and adaptive immunity (IgM). The expression of IL-1β was highest at 60 days post-fertilization (60D), while TNF-α expression peaked at 25D before dropping notably by 60D. iNOS showed a peak at 7D, underscoring its importance in early immune defence. LYS exhibited a high expression at 10D, while HAMP peaked at 60D, highlighting their roles in antimicrobial defence. Stress marker HSP70 increased from 15D onwards and complement component C3 was consistently expressed at low levels throughout development. MHC-IIβ and CD4-1 showed significant increase since 10D and 7D respectively, suggesting the establishment of cell-mediated immunity. IgM expression increased notably from 15 days, indicating the development of adaptive immunity. In adult fish tissues, IL-1β, TNF-α, LYS and HSP70 showed highest expression in the hindgut, while C3 was predominantly expressed in the liver. MHC-IIβ and CD4-1 were highly expressed in the spleen and anterior kidney respectively. IgM was abundant in the anterior kidney and spleen. This study provides crucial baseline data on the immune competence of different developmental stages of C. dussumieri, informing strategies for effective vaccination and disease management in aquaculture, and enhancing our understanding of fish immunology for conservation efforts.

Loop-extrusion-mediated plasmid DNA cleavage by the bacterial SMC Wadjet complex.

Structural maintenance of chromosomes (SMC) complexes play pivotal roles in genome organization and maintenance across all domains of life. In prokaryotes, SMC-family Wadjet complexes structurally resemble the widespread MukBEF but serve a defensive role by inhibiting plasmid transformation. We previously showed that Wadjet specifically cleaves plasmid DNA; however, the molecular mechanism underlying plasmid recognition remains unclear. Here, we use invitro single-molecule imaging to directly visualize DNA loop extrusion and plasmid cleavage by Wadjet. We find that Wadjet is a symmetric loop extruder that simultaneously reels in DNA from both sides of a loop and that this activity requires a dimeric JetABC supercomplex. On surface-anchored plasmid DNAs, Wadjet extrudes the full length of a 44-kb-pair plasmid, stalls, and cleaves DNA. Our findings reveal the role of loop extrusion in the specific recognition and elimination of plasmids by Wadjet and establish loop extrusion as an evolutionarily conserved mechanism among SMC complexes across all kingdoms of life.

Genome-wide identification and expression analysis of genes encoding late embryogenesis proteins in Cicer arietinum

Late embryogenesis abundant (LEA) proteins play defensive roles during seed maturation and seed germination processes. However, there is no such investigation was carried out in chickpea. In present study, genome wide identification and characterization of LEA encoding genes has been investigated, and identified 65 and 74 LEA encoding genes in desi and kabuli cultivar of chickpea, respectively. All these genes have been classified into eight subfamilies on the bases of their phylogenetic analysis and conserved domain. Maximum members of LEA encoding genes were found to be a part of the LEA_2 gene family. The analysis of physicochemical properties of LEAs was also conducted. LEA encoding genes have been found to be located in all chromosomes (8 chr) of chickpea and identified as involved in response to stimulus, biological processes, molecular functions and cellular components based upon gene ontology analysis. Gene expression analysis of randomly selected 8 LEA encoding genes has been carried out during different seed developmental stages which revealed the higher expression of LEA encoding genes during later stage of seed development in chickpea and proved their potential role in desiccation process during seed maturation. During seed germination, expression analysis of LEA encoding genes was found to be higher during the initial stages of seed germination. In conclusion, this work highlights the genome wide identification and characterization of LEA encoding genes in chickpea and proposed potential roles during seed developmental processes. This information could also be useful as a reference investigation for molecular breeding of chickpea for recalcitrant behaviour of seed.

Unveiling the microbiome marvels for its role in plant defence and resilience for sustainable agriculture

Unveiling the microbiome marvels for its role in plant defence and resilience for sustainable agriculture

Dynamics of a Prey-Predator Model: Untangling the Role of Fear-Induced Allee Effect, Prey Refuge, and Group Defense

Dynamics of a Prey-Predator Model: Untangling the Role of Fear-Induced Allee Effect, Prey Refuge, and Group Defense

Tamm-Horsfall protein augments neutrophil NETosis during urinary tract infection.

Urinary neutrophils are a hallmark of urinary tract infection (UTI), yet the mechanisms governing their activation, function, and efficacy in controlling infection remain incompletely understood. Tamm-Horsfall glycoprotein (THP), the most abundant protein in urine, uses terminal sialic acids to bind an inhibitory receptor and dampen neutrophil inflammatory responses. We hypothesized that neutrophil modulation is an integral part of THP-mediated host protection. In a UTI model, THP-deficient mice showed elevated urinary tract bacterial burdens, increased neutrophil recruitment, and more severe tissue histopathological changes compared to WT mice. Furthermore, THP-deficient mice displayed impaired urinary NETosis during UTI. To investigate the impact of THP on NETosis, we coupled in vitro fluorescence-based NET assays, proteomic analyses, and standard and imaging flow cytometry with peripheral human neutrophils. We found that THP increases proteins involved in respiratory chain, neutrophil granules, and chromatin remodeling pathways, enhances NETosis in an ROS-dependent manner, and drives NET-associated morphologic features including nuclear decondensation. These effects were observed only in the presence of a NETosis stimulus and could not be solely replicated with equivalent levels of sialic acid alone. We conclude that THP is a critical regulator of NETosis in the urinary tract, playing a key role in host defense against UTI.

Utilizing the mutant library to investigate the functional characterization of GhGLR3.4 regulating jasmonic acid to defense pest infestation.

The glutamate receptor (GLR) serves as a ligand-gated ion channel that plays a vital role in plant growth, development, and stress response. Nevertheless, research on GLRs in cotton is still very limited. The present study conducted a comprehensive analysis of GLRs gene family in cotton. In total, 41 members of the GLR family were identified in cotton unveiling distinct subgroups in comparison to Arabidopsis. Among these members, the third subgroup highlights its pivotal role in cotton's defense against insect infestation. Furthermore, the CRISPR/Cas9 system was utilized to create a mutant library of GLR members, which consisted of a total of 135 independent mutant lines, resulting in the production of novel cotton materials with valuable breeding potential for pest control. Further, this study elucidates the influence of GhGLR3.4 on jasmonic acid (JA) pathway signal transduction and demonstrated its participation in the influx of intracellular Ca2+, which regulates "calcium transients" following stimulation, thereby influencing multiple intracellular reactions. The study also found that GhGLR3.4 influences the synthesis of the JA pathway and actively partakes in long-distance signal transmission among plants, facilitating the transfer of defense signals to neighbor leaves and thereby triggering systemic defense. Consequently, this research advances our knowledge of plants' comprehensive defense mechanism against insect pest infestation.

SPIRRIG is required for BRICK1 stability and salt stress induced root hair developmental plasticity in Arabidopsis

Developmental plasticity is critical for plants to adapt to constantly changing environments. Plant root hairs display dramatic plasticity under different environments and therefore play crucial roles in defense against environmental stressors. Here, we report the isolation of an Arabidopsis mutant, salinityover-sensitivemutant 1–1 (som1-1), also exhibiting root hair developmental defects. Map-based cloning and allelic analyses confirmed that som1-1 is a new mutant allele of SPIRRIG (SPI), which encodes a Beige and Chediak Higashi (BEACH) domain-containing protein. SPI has been reported to facilitate actin dependent root hair development by temporally and spatially regulating the expression of BRICK1 (BRK1), a subunit of the SCAR/WAVE actin nucleating promoting complex. Our living cell imaging examinations revealed that salt stress induces an altered actin organization in root hair that mimics those in the spi mutant, implying SPI may respond to salt stress induced root hair plasticity by modulating actin cytoskeleton organization. Furthermore, we found BRK1 is also involved in root hair developmental change under salt stress, and overexpression of BRK1 resulted in root hairs over-sensitive to salt stress as those in spi mutant. Moreover, based on biochemical analyses, we found BRK1 is unstable and SPI mediates BRK1 stability. Functional loss of SPI results in the accumulation of steady-state of BRK1.

Construction and biological activity of metallothionein fused with ELP

Metallothionein (MT) plays a significant role in heavy metal removal, antioxidant defense, and immune regulation. The current predominant approach for obtaining natural MT is extraction from tissue, which often entails complex procedures resulting in limited yields. In recent years, researchers have adopted the strategy of fusing labels such as GST or His for the heterologous expression of MT. However, a challenge in industrial production arises from the subsequent removal of these labels, which often leads to a significant reduction in the yield. The fusion with elastin-like polypeptides (ELPs) offers a promising solution for achieving soluble expression of the target protein, while providing a simple and fast purification process. In this study, ELP was fused with MT, which significantly up-regulated the soluble expression of MT. The fusion protein ELP-MT with the purity above 97% was obtained efficiently and simply by inverse transition cycling (ITC). ELP-MT exhibited a remarkable 2,2'-azinobis(3-ethylbenzothiazoline-6- sulfonic acid) ammonium salt (ABTS) scavenging activity, with the half maximal inhibitory concentration (IC50) of 0.77 μmol/L, which was 53.7 times that of the vitamin E derivative Trolox. In addition, the fusion protein demonstrated strong 1,1-diphenyl-2-trinitrohydrazine (DPPH) scavenging ability. Furthermore, ELP-MT had no toxicity to the proliferation and promoted the adhesion and migration of NIH/3T3 cells. All these results indicated that ELP-MT had good biocompatibility. We constructed the fusion protein ELP-MT combining the unique properties of MT and elastin, laying a technical foundation for the large-scale production of recombinant MT and facilitating the applications in food, health supplement, and cosmetic industries.

Assessing Different Rice Genotypes Tolerance against the Major Pests and Identifying the Biochemical Basis of Tolerance

A total of 196 rice genotypes were screened for tolerance against paddy stem borer and leaf folder pests under open field conditions. Damage assessment followed the standard evaluation procedure for rice developed by IRRI (1988). Stem borer incidence was recorded during both the vegetative and reproductive stages while leaf folder incidence was recorded at five different growth stages (30, 40, 50, 60, and 70 days after transplanting). Interestingly, tolerance to paddy stem borer varied among the genotypes. Genotypes resistant at the Vegetative Stage did not show tolerance at the Reproductive Stage. Consequently, leaf folder infestation was recorded at five different growth stages, demonstrating that although the mean infestation was considered for identifying tolerance, the rate of infestation against an accession is not consistent across all growth stages. Additionally, biochemical analysis of the resistant entries, along with a susceptible check (TN1), revealed that higher total phenol concentrations, moderate chlorophyll content, and lower sugar levels were key factors contributing to pest tolerance. The correlation between infestation percentage and biochemical parameters showed a high positive correlation between total sugars and infestation percentage and a strong negative correlation between total phenols and infestation percentage, indicating that phenols play a role in plant defense.

Neuroimmune signalling pathways in chronic rhinosinusitis with nasal polyps

Purpose of review To evaluate the role of neuroimmune signalling pathways in the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP). Recent findings The sinonasal mucosa is densely infiltrated by immune cells and neuronal structures that share an intimate spatial relationship within tissue compartments. Together, such neuroimmune units play a critical role in airway defence and homeostatic function. CRSwNP is primarily driven by a type 2 immune endotype in the majority of patients. So far, central and peripheral neuronal mechanisms that promote, regulate and enhance immune responses have not been investigated to any detail within this disease group. Neurogenic inflammation, mediated by neuropeptides such as substance P and calcitonin gene-related peptide (CGRP), has been shown to modulate immune responses. Emerging evidence now suggests a bidirectional communication between immune cells and neurons, with inflammatory cytokines directly activating sensory neurons and influencing their function alongside the nervous system directly modulating immune cells. Summary The complex interplay between epithelial cells, immune cells and neurons in CRSwNP presents both challenges and opportunities for therapeutic intervention. Understanding these neuroimmune interactions not only provides valuable insights into the pathogenesis of CRSwNP but also may open up new avenues for therapeutic strategies targeting both the inflammatory and neuronal components of the disease.

Calnexin interacts with B-cell receptor-associated protein 31 (Bap31) to mediate coelomocyte phagocytosis and Vibrio splendidus clearance in Apostichopus japonicus

Calnexin serves as a lectin chaperone located on the endoplasmic reticulum membrane and functions in glycoprotein folding and synthesis quality control, as well as in Ca2+ storage. Calnexin is extensively documented to participate in host immunity in the endoplasmic reticulum. However, the functions and fundamental mechanisms of calnexin in the invertebrate innate defence remain largely unknown. In this research, the complete cDNA sequence for calnexin from Apostichopus japonicus (Ajcalnexin) was cloned, revealing a 1779 bp open reading frame that codes for 592 amino acids, 113 bp 5′-Untranslated Region (UTR), and 3251 bp 3′-UTR. Upon Vibrio splendidus infection, both AjCalnexin mRNA and protein levels were significantly increased in coelomocytes. Knocking down Ajcalnexin with specific siRNAs significantly decreased coelomocyte phagocytosis, reducing the intracellular load of V. splendidus. By contrast, overexpression of AjCalnexin using recombinant AjCalnexin protein (rAjCalnexin) had the opposite effect. Moreover, B-cell receptor-associated protein 31 of A. japonicus (AjBap31) was identified as an interacting partner of AjCalnexin, which positively regulates AjBap31 expression. Silencing Ajbap31 also decreased coelomocyte phagocytosis and inhibited the intracellular load of V. splendidus. Furthermore, phagocytosis levels and intracellular loads of V. splendidus in the coelomocytes of sea cucumbers treated with rAjCalnexin and siAjBap31 were significantly lower than those in rAjCalnexin- and siNC-treated sea cucumbers. Collectively, we provide the first functional evidence that the AjCalnexin-AjBap31 axis plays a crucial role in host immune defence by mediating coelomocyte phagocytosis in A. japonicus during V. splendidus infection. These findings enhance understanding of the regulatory mechanism of phagocytosis in echinoderms and offer theoretical insights for preventing and controlling skin ulcer syndrome in sea cucumbers.

Porcine non-conventional B-1-like cells are a potent source of Streptococcus suis-binding IgM.

Streptococcus suis serotype (cps) 2 is an important bacterial pathogen in piglet nurseries and an emerging zoonotic agent without effective vaccines available. Immunoglobulin (Ig)M plays an essential role in host defense against S. suis. In mice, non-conventional B-1 cells are a major source of protective IgM against encapsulated bacterial pathogens, such as S. pneumoniae. Two IgM+CD21- B-1-like cell subpopulations, distinguishable by CD11R1 expression, were described in pigs, but their properties and functions are poorly understood. This study aimed at a first characterization of the porcine early IgM B cell response against S. suis cps 2. We analyzed the same healthy pigs, naturally colonized by different S. suis serotypes, including cps 2, at four and eight weeks of age serologically and determined the frequency of different peripheral B cell subpopulations by flow cytometry. Furthermore, we isolated conventional IgM+CD21+ B-2 cells as well as non-conventional B-1-like cell subpopulations from peripheral blood of eight-weeks-old pigs to evaluate their potential of IgM secretion in response to innate and adaptive stimuli in vitro. Between the fourth and eighth week of life, a characteristic increase of S. suis cps 2-binding serum IgM antibodies, restricting bacterial growth, was observed. Moreover, we show for the first time that the significant increase of anti-S. suis serum IgM is associated with a relative increase of peripheral non-conventional IgM+CD21- B-1-like cells in vivo, particularly of the IgM+CD21- CD11R1- subpopulation. Noteworthy, sorted IgM+CD21- CD11R1- B-1-like cells from eight-weeks-old pigs spontaneously secreted IgM in vitro. In addition, both non-conventional IgM+CD21- B cell subpopulations, in contrast to conventional IgM+CD21+ B-2 cells, produced anti-S. suis IgM upon toll-like receptor (TLR) stimulation underlining their innate-like characteristics. We furthermore observed that both B-1-like subpopulations secrete S. suis cps 2-binding IgM upon stimulation with T cell-associated factors with highest amounts in IgM+CD21-CD11R1- B-1-like cells even exceeding anti-S. suis IgM levels produced by B-2 cells. Porcine non-conventional B-1-like cells are a potent source of S. suis-binding IgM indicating a role in immunity during a critical phase of piglet rearing.

Ascorbate peroxidase modulation confirms key role in Leishmania infantum oxidative defence

BackgroundAscorbate peroxidase (APX) has emerged as a promising target for chemotherapy because of its absence in humans and crucial role in the antioxidant defence of trypanosomatids. APXs, which are class I haeme-containing enzymes, reduces hydrogen peroxide using ascorbate to produce water and monodehydroascorbate, thereby preventing cell damage caused by H2O2.MethodsWe aimed to create an APX-knockout L. infantum line using CRISPR/Cas9. Despite unsuccessful attempts at full knockouts, we achieved deletion of chromosomal copies post-APX episomal insertion, yielding LiΔchrAPX::LbAPX parasites. We performed phenotypic characterization to assess the impact of these genetic modifications, which included the determination of APX transcript expression levels using quantitative PCR, drug sensitivity, infectivity, and parasite survival in macrophages.ResultsQuantitative polymerase chain reaction (PCR) analysis revealed a 10- to 13-fold reduction in APX transcript expression in LiΔchrAPX::LbAPX compared with wild-type (LiWT) and APX-overexpressing (Li::Cas9::LbAPX) parasites, respectively. The episomes in those knockdown parasites remained stable even after 20 drug-free passages in vitro. Li::Cas9::LbAPX parasites showed increased resistance to trivalent antimony (SbIII) and isoniazid, reduced tolerance to H2O2, and unchanged macrophage infectivity compared with LiWT. In contrast, LiΔchrAPX::LbAPX parasites were more sensitive to SbIII and isoniazid, exhibited greater susceptibility to H2O2-induced oxidative stress, and 72 h post-infection, showed fewer infected macrophages and intracellular amastigotes compared with LiWT parasites.ConclusionsOur findings hint at the indispensability of APX in L. infantum and raise the possibility of its potential as a therapeutic target for leishmaniasis.Graphical

Short term high‐fat diet induced liver ILC1 differentiation associated with the TLR9 activation

The health impact of dietary fat is a significant nutritional concern. However, the effects of high-fat diet on immune system particularly the liver regional immune function remains still unclear. Liver ILC1 has been recently identified as playing crucial roles in anti-viral defense, liver regeneration, and protection against acute liver injury. Here, in a mouse model, we uncovered that short term high-fat diet for 2 weeks obviously increased the frequency and number of ILC1 in liver. The production of TNF-α and expressions of TRAIL, CXCR3 and CXCR6 were also increased. Furthermore, EASY-RNAseq and ATAC-seq of liver ILC1 clarified the transcriptome characteristics and chromatin accessibility in response to short term high-fat diet, which were involved with lymphocyte differentiation. Mechanistically, we demonstrated that accumulation of liver ILC1 induced by short term high-fat diet was dependent on a TLR9-mediated differentiation through TLR9 inhibitor. Taken together, these findings shed light on the effect and underlying mechanism of short term high-fat diet on liver ILC1 differentiation and provide nutritional strategies and theoretical basis for the liver regional immune function regulation.

A defensive pathway from NAC and TCP transcription factors activates a BAHD acyltransferase for (Z)-3-hexenyl acetate biosynthesis to resist herbivore in tea plant (Camellia sinensis).

Numerous herbivore-induced plant volatiles (HIPVs) play important roles in plant defense. In tea plants (Camellia sinensis), (Z)-3-hexenyl acetate (3-HAC) has been characterized as associated with resistance to herbivores. To date, how tea plants biosynthesize and regulate 3-HAC to resist herbivores remain unclear. Based on transcriptomes assembled from Ectropis obliqua-fed leaves, a cDNA encoding BAHD acyltransferase, namely CsCHAT1, was highly induced in leaves fed with E. obliqua. Enzymatic assays showed that CsCHAT1 converted (Z)-3-hexenol into 3-HAC. Further suppression of CsCHAT1 expression reduced the accumulation of 3-HAC and lowered the resistance of tea plants to E. obliqua, while 3-HAC replenishment rescued the reduced resistance of CsCHAT1-silenced tea plants against E. obliqua. Two transcription factors (TFs), CsNAC30 and CsTCP11, were co-expressed with CsCHAT1. An integrative approach of biochemistry, DNA-protein interaction, gene silencing, and metabolic profiling revealed that the two TFs positively regulated the expression of CsCHAT1. The suppression of either one decreased the production of 3-HAC and eliminated the resistance of tea plants to E. obliqua. Notably, the suppression of either one considerably impaired JA-induced 3-HAC biosynthesis in tea plant. The proposed pathway can be targeted for innovative agro-biotechnologies protecting tea plants from damage by E. obliqua.

Aspergillus terreus IFM 65899-THP-1 cells interaction triggers production of the natural product butyrolactone Ia, an immune suppressive compound.

We focused on the possibility that pathogenic microorganisms might produce immune suppressors to evade the action of immune cells. Based on this possibility, we have recently developed new co-culture method of pathogenic actinomyces and immune cells, however, the interaction mechanism between pathogens and cells was still unclear. In this report, co-culturing pathogenic fungi and immune cells were investigated. Pathogenic fungus Aspergillus terreus IFM 65899 and THP-1 cells were co-cultured and isolated a co-culture specific compound, butyrolactone Ia (1). 1 inhibits the production of nitric oxide by RAW264 cells and exhibits regulatory effects on autophagy, suggesting 1 plays a defensive role in the response of A. terreus IFM 65899 to immune cells. Furthermore, dialysis experiments and micrographs indicated that "physical interaction" between A. terreus IFM 65899 and THP-1 cells may be required for the production of 1. This is the first report of co-culture method of fungi with immune cells and its interaction mechanism.

Comparative Analysis of Phytochemicals and Gene Expression in Soybean (Glycine max) Under Acute Moderated and Severe Elevated Ozone: Unravelling the Role of Antioxidant Defence

ABSTRACTThe increasing concentrations of ground‐level ozone (O3) resulting from industrialisation and anthropogenic activities present a substantial environmental threat to agricultural productivity, particularly affecting O3‐sensitive crops such as soybeans. The effects of acute O3 exposure on soybean yield attributes and seed quality and whether soybean showed different detoxification mechanisms in response to moderate and severe O3 stress are not extensively explored. In this study, soybean seedlings were exposed to moderate (80 nmol mol−1) and acute severe (200 nmol mol−1) O3 stress, and then growth parameters, yield attributes, reactive oxygen species (ROS) levels, enzymatic and non‐enzymatic antioxidant properties and associated gene expression in the leaves were assessed. The results revealed that moderate O3 exposure enhanced growth parameters but reduced the 100‐grain weight, while acute severe exposure sharply depressed growth parameters, yield attributes and the 100‐grain weight. Moderate O3 fumigation significantly increased hydrogen peroxide (H2O2) levels and catalase (CAT) activity from 4 to 32 h. Acute severe O3 stress induced the overproduction of superoxide anions (O2.−) and H2O2 during nearly the whole experiment period, but only enhanced superoxide dismutase (SOD) activity at 32 h, and showed no stimulatory effects on CAT activity. Additionally, the relative expression levels of the SOD and CAT gene family in soybean leaves exposed to elevated O3 were upregulated, peaking at 8 h. Moderate O3 treatment enhanced reduced glutathione (GSH) and ascorbate (AsA) levels and increased the activities of AsA–GSH cycle‐related enzymes. In contrast, acute severe O3 exposure inhibited GSH and AsA contents and markedly suppressed AsA–GSH cycle‐related enzymes, particularly from 8 to 32 h. Redundancy analysis indicated that CAT and AsA play crucial roles in scavenging O3‐induced ROS under moderate stress, while ascorbate peroxidase (APX) and GSH were more effective under acute severe stress conditions. These findings provide insights into the differential impacts of acute O3 stress on soybeans, emphasising the importance of considering both crop yield and grain quality in assessing O3 risks to crops.