Search Results (515)

Potato (Solanum tuberosum L.) is a globally significant staple crop that faces constant threats from Phytophthora infestans, the causative agent of late blight (LB). The battle between Phytophthora infestans and its host is driven by the molecular interplay of RXLR-encoded avirulence (PiAvr) effectors and nucleotide-binding leucine-rich repeat (NLR) immune receptors in potato. This review provides a comprehensive analysis of the structural characteristics, functional diversity, and evolutionary dynamics of RXLR effectors and the mechanisms by which NLR receptors recognize and respond to them. The study elaborates on both direct and indirect modes of effector recognition by NLRs, highlighting the gene-for-gene interactions that underlie resistance. Additionally, we discuss the molecular strategies employed by P. infestans to evade host immunity, including effector polymorphism, truncation, and transcriptional regulation. Advances in structural biology, functional genomics, and computational modeling have provided valuable insights into effector–receptor interactions, paving the way for innovative resistance breeding strategies. We also discuss the latest approaches to engineering durable resistance, including gene stacking, synthetic NLRs, and CRISPR-based modifications. Understanding these molecular mechanisms is critical for developing resistant potato cultivars and mitigating the devastating effects of LB. This review aims to bridge current knowledge gaps and guide future research efforts in plant immunity and disease management. Full article

The progression of inflammation during sepsis represents a multifaceted biological cascade that requires effective therapeutic interventions to improve survival. In septic neonatal foals, oxidative stress (OS) arises due to a compromised antioxidant defense system. Oxidative stress may disrupt the functionality of redox-sensitive organelles, such as the endoplasmic reticulum (ER). Endoplasmic reticulum stress disorder affects multiple cellular signaling pathways, including redox balance, inflammation, and apoptosis, and contributes to the pathogenesis of sepsis. The study aimed to elucidate whether OS conditions in sepsis influenced gene expression associated with ER stress. Blood samples were collected from 7 healthy and 21 hospitalized neonatal foals and processed for RNA extraction. RNA sequencing was employed to identify ER stress-responsive genes. Novel findings reported here indicate activation of the ER stress pathway in foals with sepsis. Several genes associated with ER stress, such as clusterin (CLU), BCL2-like 1 (BCL2L1), ubiquitin specific peptidase 14 (USP14), bifunctional apoptosis regulator (BFAR), and optic atrophy 1 (OPA1), were upregulated and positively correlated with sepsis scores and negatively correlated with the combined activities of antioxidant enzymes. In contrast, X-box binding protein 1 (XBP1), homocysteine inducible ER protein with ubiquitin-like domain 1 (HERPUD1), leucine-rich repeat kinase 2 (LRRK2), and selenoprotein S (SELENOS) were negatively correlated with sepsis scores and were downregulated in sepsis and positively correlated with the combined activities of antioxidant enzymes. Furthermore, a positive correlation was observed between cAMP responsive element binding protein 3 like 2 (CREB3L2) and BCL2L1, as well as between the expressions of USP14 and YOD1 deubiquitinase (YOD1) in sepsis. Similarly, the expression levels of XBP1 and Herpud1 demonstrated a positive correlation with each other in sepsis. Additionally, the downregulation of genes with protective function against OS, such as XBP1, HERPUD1, and SELENOS, in septic foals also highlights their significance in mitigating OS in sepsis treatment. The study reported here highlights the potential of ER stress as a promising therapeutic target and prognostic marker in septic foals. Full article

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), represents a major global threat to wheat (Triticum aestivum. L). Planting varieties with adult-plant resistance (APR) is an effective approach for long-term management of this disease. The Chinese winter wheat variety Lantian 25 exhibits moderate-to-high APR against stripe rust under field conditions. To investigate the genetic basis of APR in Lantian 25, a set of 219 F₆ recombinant inbred lines (RILs) was created from a cross between Lantian 25 (resistant parent) and Huixianhong (susceptible parent). These RILs were assessed for maximum disease severity (MDS) in Pixian of Sichuan and Qingshui of Gansu over the 2020–2021 and 2021–2022 growing seasons, resulting in data from four different environments. Genotyping was performed on these lines and their parents using the wheat Illumina 50K single-nucleotide polymorphism (SNP) arrays. Composite interval mapping (CIM) identified six quantitative trait loci (QTL), named QYr.gaas-2BS, QYr.gaas-2BL, QYr.gaas-2DS, QYr.gaas-2DL, QYr.gaas-3BS and QYr.gaas-4BL, which were consistently found across two or more environments and explained 4.8–12.0% of the phenotypic variation. Of these, QYr.gaas-2BL, QYr.gaas-2DS, and QYr.gaas-3BS overlapped with previous studies, whereas QYr.gaas-2BS, QYr.gaas-2DS, and QYr.gaas-4BL might be novel. All the resistance alleles for these QTL originated from Lantian 25. Furthermore, four kompetitive allele-specific PCR (KASP) markers, Kasp_2BS_YR (QYr.gaas-2BS), Kasp_2BL_YR (QYr.gaas-2BL), Kasp_2DS_YR (QYr.gaas-2DS) and Kasp_2DL_YR (QYr.gaas-2DL), were developed and validated in 110 wheat diverse accessions. Additionally, we identified seven candidate genes linked to stripe rust resistance, including disease resistance protein RGA2, serine/threonine-protein kinase, F-box family proteins, leucine-rich repeat family proteins, and E3 ubiquitin-protein ligases. These QTL, along with their associated KASP markers, hold promise for enhancing stripe rust resistance in wheat breeding programs. Full article

Sepsis is a life-threatening condition caused by an abnormal host response to infection, leading to organ dysfunction and potentially death. Acute kidney injury (AKI) is a critical complication of sepsis. Various pathways, especially signaling through Toll-like receptors (TLRs) and the nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain-containing protein 3 (NLRP3) inflammasome, contribute to inflammation and tissue damage. Cilastatin, a renal dehydropeptidase I inhibitor, has shown promise in protecting against AKI induced by nephrotoxic drugs. This study assessed cilastatin’s effectiveness in preventing AKI and inflammation caused by sepsis and its impact on survival. Sepsis was induced in male Sprague-Dawley rats using the cecal ligation puncture (CLP) model, with four groups: sham (control), CLP, sham + cilastatin, and CLP + cilastatin. Cilastatin (150 mg/kg) was administered immediately and 24 h after sepsis induction. Kidney injury was evaluated 48 h later by assessing serum creatinine, blood urea nitrogen, glomerular filtration rate, proteinuria, kidney injury molecule-1 levels, and renal morphology. Inflammatory and fibrotic biomarkers, particularly related to the TLR4 and NLRP3 pathways, were also measured. Cilastatin treatment prevented kidney dysfunction, reduced inflammatory markers, and improved survival by 33%. These results suggest that cilastatin could be a beneficial therapeutic strategy for sepsis-related AKI, improving outcomes and reducing mortality. Full article

Inorganic polyphosphate (iPolyP) is a ubiquitous molecule composed of a variable number of orthophosphate units. Recent studies have highlighted its involvement in colorectal cancer (CRC) cell proliferation. However, further investigations are needed to elucidate its role in CRC cell progression and migration, as well as its influence on the tumor microenvironment. This study focuses on the inorganic polyphosphate (iPolyP)/transient receptor potential cation channel subfamily M member 8 (TRPM8) axis and its impact on CRC progression. To investigate these issues, western blotting, fixed and live cells immunofluorescence, 2D and 3D cell culture on CRC-patient derived tissues, ELISA, and wound healing assays were performed. Our results show that inorganic polyphosphate induces the expression of epithelial-to-mesenchymal transition (EMT) markers in CRC cells. Furthermore, the iPolyP/TRPM8 axis indirectly promotes tumor growth through activation of the Nucleotide-binding oligomerization domain, Leucine-rich Repeat and Pyrin domain-containing protein 3 (NLRP3) inflammasome in immune cells, leading to increased levels of the pro-inflammatory cytokine interleukin-1β (IL-1β) in the tumor microenvironment (TME), thereby advancing CRC. These findings suggest that targeting the iPolyP/TRPM8 pathway may be a promising strategy to inhibit CRC progression and metastasis. Full article

Barley leaf stripe, caused by Pyrenophora graminea (Pg), significantly reduces yields across various regions globally. Understanding the resistance mechanisms of barley to Pg is crucial for advancing disease resistance breeding efforts. In this study, two barley genotypes—highly susceptible Alexis and immune Ganpi2—were inoculated with the highly pathogenic Pg isolate QWC for 7, 14, and 18 days. The number of differentially expressed genes (DEGs) in Alexis was 1350, 1898, and 2055 at 7, 14, and 18 days, respectively, while Ganpi2 exhibited 1195, 1682, and 2225 DEGs at the same time points. Gene expression pattern analysis revealed that Alexis responded more slowly to Pg infection compared to Ganpi2. A comparative analysis identified 457 DEGs associated with Ganpi2’s immunity to Pg. Functional enrichment of these DEGs highlighted the involvement of genes related to plant-pathogen interactions and kinase activity in Pg immunity. Additionally, 20 resistance genes and 24 transcription factor genes were predicted from the 457 DEGs. Twelve candidate genes were selected for qRT-PCR verification, and the results showed that the transcriptomic data was reliable. We conducted cloning of the candidate Pg resistance gene HvLRR_8-1 by the barley cultivar Ganpi2, and the sequence analysis confirmed that the HvLRR_8-1 gene contains seven leucine-rich repeat (LRR) domains and an S_TKc domain. Subcellular localization in tobacco indicates that the HvLRR_8-1 is localized on the cell membrane. Through the functional analysis using virus-induced gene silencing, it was demonstrated that HvLRR_8-1 plays a critical role in regulating barley resistance to Pg. This study represents the first comparative transcriptome analysis of barley varieties with differing responses to Pg infection, providing that HvLRR_8-1 represents a promising candidate gene for improving durable resistance against Pg in cultivated barley. Full article

This study identifies and classifies resistance gene analogues (RGAs) in the genomes of Brassica nigra, Sinapis arvensis and Sinapis alba using the RGAugury pipeline. RGAs were categorised into four main classes: receptor-like kinases (RLKs), receptor-like proteins (RLPs), nucleotide-binding leucine-rich repeat (NLR) proteins and transmembrane-coiled-coil (TM-CC) genes. A total of 4499 candidate RGAs were detected, with species-specific proportions. RLKs were the most abundant across all genomes, followed by TM-CCs and RLPs. The sub-classification of RLKs and RLPs identified LRR-RLKs, LRR-RLPs, LysM-RLKs, and LysM-RLPs. Atypical NLRs were more frequent than typical ones in all species. Atypical NLRs were more frequent than typical ones in all species. We explored the relationship between chromosome size and RGA count using regression analysis. In B. nigra and S. arvensis, larger chromosomes generally harboured more RGAs, while S. alba displayed the opposite trend. Exceptions were observed in all species, where some larger chromosomes contained fewer RGAs in B. nigra and S. arvensis, or more RGAs in S. alba. The distribution and density of RGAs across chromosomes were examined. RGA distribution was skewed towards chromosomal ends, with patterns differing across RGA types. Sequence hierarchical pairwise similarity analysis revealed distinct gene clusters, suggesting evolutionary relationships. The study also identified homologous genes among RGAs and non-RGAs in each species, providing insights into disease resistance mechanisms. Finally, RLKs and RLPs were co-localised with reported disease resistance loci in Brassica, indicating significant associations. Phylogenetic analysis of cloned RGAs and QTL-mapped RLKs and RLPs identified distinct clusters, enhancing our understanding of their evolutionary trajectories. These findings provide a comprehensive view of RGA diversity and genomics in these Brassicaceae species, providing valuable insights for future research in plant disease resistance and crop improvement. Full article

Background: The spleen is the primary reservoir of immune cells in mammals. Diverse stimuli can disrupt spleen homeostasis, resulting in spleen injury and immune dysfunction. This study employed a porcine model to assess the therapeutic potential of salvianolic acid B (SAB) against lipopolysaccharide (LPS)-induced splenic injury. Methods: Seventy-two male weanling piglets were randomly assigned to one of four groups: CON-SS, SAB-SS, CON-LPS, and SAB-LPS. The CON-SS and CON-LPS groups received a basal diet, while SAB-SS and SAB-LPS groups received a SAB-supplemented diet. After 14 d, the CON-SS and SAB-SS groups received an intraperitoneal injection of sterile saline, whereas the CON-LPS and SAB-LPS groups were injected with LPS. Blood and spleen tissues were harvested 6 h post-injection for biochemical analysis. Results: LPS induced systemic immune disorders in piglets, as evidenced by increased immune organ indices and decreased white blood cell, lymphocyte, and basophil counts in blood (p < 0.05). LPS also caused histoarchitectural disruption, cell apoptosis, oxidative stress, and inflammation in the spleen (p < 0.05). Conversely, SAB improved splenic histopathology and reduced splenic apoptosis and pro-inflammatory mediators in piglets (p < 0.05). SAB significantly mitigated peroxidation accumulation by facilitating the nuclear translocation of nuclear factor erythroid 2-related factor 2 and strengthening the antioxidant system, and inhibited nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain-containing 3 (NLRP3) inflammasome activation (p < 0.05). Mechanistically, SAB attenuated LPS-induced splenic oxidative stress and NLRP3 inflammasome activation by restoring mitochondrial structure and function (p < 0.05). Conclusions: This research unveils that SAB alleviates LPS-induced spleen disorder by reinforcing antioxidant system and suppressing NLRP3 inflammasome, highlighting SAB’s potential as a prospective therapeutic agent for spleen disorders. Full article

Ultraviolet (UV) radiation stimulates melanogenesis, leading to various esthetic problems. UV increases oxidative stress and nuclear factor-kappa B (NF-κB), which increase the nucleotide-binding oligomerization domain (NOD) or leucine-rich repeat and pyrin do-main containing 3 (NLRP3) inflammasome. Given that polydeoxyribonucleotides reduce melanogenesis and polynucleotide (PN) has molecular similarity to polydeoxyribonucleotides, we hypothesized that PN can decrease melanogenesis. We compared the anti-melanogenic effect of PN with that of a PN mixture (PNM) that contained other antioxidants, such as glutathione and hyaluronic acid, in UVB-irradiated keratinocytes and animal skin. PN and PNM both decreased oxidative stress, which was evaluated according to the expression of NADPH oxidase (NOX) 1/2/4, the glutathione (GSH):oxidized glutathione (GSSG) ratio, and 8-hydroxy-2′-deoxyguanosine (8-OHdG) in UVB-irradiated keratinocytes. The expression of NLRP3 inflammasome components (NLRP3, ASC, and pro-caspase-1) and IL-18 was increased by UVB radiation and reduced by PN and PNM. When conditioned media from PN or PNM were administered to UVB-radiated keratinocytes, melanogenesis-related signals (MITF, tyrosinase, and tyrosinase-related protein1/2) were decreased. These effects were similar in the UVB-irradiated animal skin. Both PN and PNM decreased melanin accumulation and increased skin lightness in UVB-irradiated skin. The anti-melanogenic effect of PNM was greater than that of PN. In conclusion, PN and PNM decreased melanogenesis by decreasing oxidative stress, NF-κB, and NLRP3 inflammasome activation. Full article

We previously showed that selective suppression of CD44 in the corneal epithelium leads to structural abnormalities in the mouse cornea. Our comparative studies of young and aged ocular biopsies revealed that CD44 expression is downregulated in aged corneas, while leucine-rich repeats and immunoglobulin-like domain 1 (Lrig1+) stem cells remain preserved in the peripheral limbus. These findings suggest an age-related shift in the corneal stem cell compartmentalization, characterized by impaired CD44 expression in the central cornea and preservation of Lrig1+ stem cells in the limbus, which become the main stem cells in the senescent cornea. To investigate this further, we performed topical tamoxifen-inducible, diphtheria toxin-mediated ablation of Lrig1+ stem cells in mouse corneas. We then assessed both activated and non-activated beta-catenin expression in wild-type (WT) and CD44 knockout (CD44KO) mice, given that CD44 modulates the Wingless-related integration site (Wnt) pathway. Our results indicate that two distinct stem cell populations operate in the mouse cornea: Lrig1-derived stem cells and Wnt-activity/CD44-dependent stem cells. The Lrig1-derived cells act as a reservoir of quiescent stem cells that regenerate the cornea upon injury, whereas under homeostatic conditions, the Wnt-activity/CD44-dependent stem cells are primarily responsible for corneal renewal. In the aged cornea, the loss of CD44 expression leads to reduced Wnt signaling, making the tissue increasingly dependent on Lrig1+ stem cells for regeneration. In mice, Lrig1+ stem cells are capable of sustaining permanent corneal renewal, even in the absence of CD44. Full article

The female gametophyte is central to the reproductive success of flowering plants, with its development being tightly controlled by an intricate network of genes and signaling pathways. A deeper understanding of these regulatory mechanisms is essential for uncovering the complexities of plant growth and development. Recent studies have shed light on various aspects of female gametophyte development, highlighting the role of specific gene and signaling networks. Among these, the ERECTA family of leucine-rich repeat receptor-like kinase (RLK) in Arabidopsis thaliana has emerged as a key player, influencing multiple biological processes, particularly those governing reproductive development of the female gametophyte. This review focuses on the significant progress made in understanding the ERECTA family’s involvement in germline cell development, emphasizing its functional roles and signaling mechanisms in female gametophyte development. Full article

Background: The increasing prevalence of processed foods has significantly elevated dietary phosphorus intake globally, posing a risk to skeletal health. Elevated serum phosphate promotes parathyroid hormone (PTH) release, leading to bone resorption and decreased bone formation. Objective: This study investigated the influence of chronically elevated phosphorus intake on bone structure in rats with normal renal function, focusing on the Receptor Activator of Nuclear factor Kappa-B (RANK)/RANK ligand (RANKL)/osteoprotegerin (OPG) pathway and its related components, leucine rich repeat containing G protein-coupled receptor 4 (LGR4), and R-spondins (RSPOs). Methods: Rats were fed a high-phosphorus diet, followed by assessment of the bone microstructure and of the expression of key signalling molecules. Results: Elevated phosphorus intake induced significant bone deterioration, particularly in the trabecular bone compartment, associated with alterations in the RANK/RANKL/OPG pathway and in the LGR4 and RSPO1 and RSPO4 signalling components in bone. Moreover, we also observed changes in RANKL, RSPO1 and RSPO4 serum levels in the rats that had received a high-phosphorus diet. Conclusions: These findings highlight the detrimental impact of excessive dietary phosphorus on skeletal health, even without renal impairment, and suggest that components of this pathway, particularly RSPO1 and RSPO4, could serve as potential biomarkers of bone deterioration. The widespread consumption of phosphorus-rich processed foods underscores the importance of nutritional education to mitigate these skeletal risks in industrialized populations. Full article

Wheat (Triticum aestivum L.), a staple crop of global significance, faces constant biotic stress threats, with powdery mildew caused by Blumeria graminis f. sp. tritici (Bgt) being particularly damaging. In this study, a multi-year single-site experiment was conducted to minimize the environmental impacts, and a five-level classification system was used to assess powdery mildew resistance. A 660K SNP array genotyped 204 wheat germplasms, followed by GWAS. SNP loci with a −log₁₀(p) > 3.0 were screened and validated across repeats to identify those associated with powdery mildew (Pm) resistance. Twelve SNPs were consistently associated with Pm resistance across multiple years. Of these, three colocalized with previously reported Pm-resistance gene or QTL regions, and the remaining nine represented potentially novel loci. The candidate genes identified included leucine-rich repeat (LRR) and NB-ARC immune receptors, as well as pathogen-related, thioredoxin, and serine threonine-protein kinase genes. Overall, the SNP loci and candidate genes identified in this study provide a basis for further fine mapping and cloning of the genes involved in relation to Pm resistance. Full article

Epidural-related maternal fever (ERMF) occurs with significant incidence in women receiving local anesthetics such as ropivacaine via epidural catheter for pain relief during labor. The causal mechanism behind this phenomenon is still not fully resolved, but evidence suggests that these anesthetics cause sterile inflammation. In this observational study, we investigated a possible contributory role of the dual-specificity phosphatase-9 (DUSP9) controlling the activity of mitogen-activated protein kinases (MAPK), and also PH-domain and Leucine-rich repeat phosphatase (PHLPP) regulating AKT kinases. The data show that ropivacaine differentially affects the expression of these phosphatases in distinct cell types of the umbilical cord and placenta. The gene expression of DUSP9 was almost completely switched off in the presence of ropivacaine in HUVECs and extravillous trophoblasts for up to 6 h, while the expression of PHLPP1 was upregulated in HUVECs and syncytiotrophoblasts. Extravillous trophoblasts were identified as a source of pro-inflammatory mediators and regulatory miRNAs in response to ropivacaine. Placentae at term exhibited a distinct DUSP9 expression pattern, whether the patients belonged to the control group or received epidural analgesia with or without elevated body temperature. The observed data imply that ropivacaine induces complex effects on the MAPK and AKT pathways at the feto–maternal interface, which contribute to the ERMF phenomenon. Full article

Leucine-rich repeat receptor-like kinases (LRR-RLKs) have evolved to perceive environmental changes. Among LRR-RLKs, PEPR1 perceives the pep1 peptide and triggers defense signal transduction in Arabidopsis thaliana. In the present study, we focused on PEPR1 and PEPR2, which are the receptors of pep1, to understand the role of tyrosine phosphorylation. PEPR1-CD (cytoplasmic domain) recombinant protein exhibited strong tyrosine autophosphorylation, including threonine autophosphorylation. We subjected all tyrosine residues in PEPR1-CD to site-directed mutagenesis. The recombinant proteins were purified along with PEPR1-CD, and Western blotting was performed using a tyrosine-specific antibody. Among the 13 tyrosine residues in PEPR1-CD, the PEPR1(Y995F)-CD recombinant protein showed significantly reduced tyrosine autophosphorylation intensity compared to PEPR1-CD and other tyrosine mutants, despite little change in threonine autophosphorylation. To confirm the autophosphorylation site, we generated a phospho-specific peptide Ab, pY995. As a result, Tyr-995 of PEPR1-CD was a major tyrosine autophosphorylation site in vitro. To understand the function of tyrosine phosphorylation in vivo, we generated transgenic plants, expressing PEPR1-Flag, PEPR1(Y995F)-Flag, and PEPR1(Y995D)-Flag in a pepr1/2 double mutant background. Interestingly, the root growths of PEPR1(Y995F)-Flag and PEPR1(Y995D)-Flag were not inhibited by pep1 peptide treatment, compared to Col-0 and PEPR1-Flag (pepr1/2) transgenic plants. Also, we analyzed downstream components, which included PROPEP1, MPK3, WRKY33, and RBOHD gene expressions in four different genotypes (Col-0, PEPR1-Flag, PEPR1(Y995F)-Flag, and PEPR1(Y995D)-Flag) of plants in the presence of the pep1 peptide. Interestingly, the expressions of PROPEP1, MPK3, WRKY33, and RBOHD were not regulated by pep1 peptide treatment in PEPR1(Y995F)-Flag and PEPR1(Y995D)-Flag transgenic plants, in contrast to Col-0 and PEPR1-Flag. These results suggest that specific tyrosine residues play an important role in vivo in the plant receptor function. Full article