Search Results (834)

Silver nanoparticles (AgNPs) are extensively employed for their antimicrobial and biomedical properties, yet concerns persist regarding their potential toxicity. While AgNPs can induce oxidative stress, membrane disruption, and DNA damage, in vivo data remain inconsistent. This study investigated whether batch-to-batch variability in nominally identical AgNPs of 10 nm size contributes to divergent in vivo toxicity outcomes. CD-1 (ICR) mice were intravenously injected with a single 10 mg/kg bw dose of spherical, citrate-coated 10 nm AgNPs from three different batches purchased from the same manufacturer. The mice were euthanized 24 h post-exposure for quantitative silver determination by inductively coupled plasma–mass spectrometry (ICP–MS) and histopathological evaluation of liver, spleen, lungs, kidneys, and brain. Autometallography and immunofluorescence were used to assess silver distribution and cellular localization in the hepatobiliary system. All the batches induced hepatobiliary toxicity, characterized by hepatocellular necrosis and gallbladder wall hemorrhage, of differing severity. The most toxic batches contained higher proportions of smaller AgNPs, suggesting that differences in size distribution influence toxicological outcomes. Silver agglomerates were localized within multiple cell types, indicating internalization and cell-specific cytotoxicity. These findings highlight that minor physicochemical variations affect in vivo results, underscoring the importance of nanoparticle characterization to improve reproducibility in nanotoxicological research. Full article

OsHKT1;1, a member of the high-affinity K⁺ transporter (HKT) family, plays a key role in Na⁺ homeostasis and salinity tolerance in rice. In our previous study, multiple potential OsHKT1;1 splicing variants were identified, as well as the full-length (FL) OsHKT1;1 transcript from the salt-tolerant rice Pokkali. However, most previous studies focused solely on the full-length protein, leaving the transport functions of splice variants largely unexamined. In this study, we focused on the splice variant OsHKT1;1-V2 and compared its function and gene expression with those of OsHKT1;1-FL. Two-electrode voltage clamp experiments using Xenopus laevis oocytes revealed that the 1st start codon of OsHKT1;1-V2 is functional to exhibit bidirectional currents in bath solutions containing NaCl. Unlike the Na⁺-selective feature of OsHKT1;1-FL, OsHKT1;1-V2 primarily mediated Cl⁻ transport with weak Na⁺ selectivity, which was supported by the higher Cl⁻ accumulation in OsHKT1;1-V2–expressing oocytes. Subcellular localization analyses using oocytes and Arabidopsis mesophyll cells indicated plasma membrane localization of OsHKT1;1-V2, similar to OsHKT1;1-FL. Functional assays using a yeast mutant further indicated that OsHKT1;1-FL, but not OsHKT1;1-V2, mediates Na⁺ uptake. The same OsHKT1;1 variants were identified in the japonica cultivar Nipponbare, and OsHKT1;1-V2 of the cultivar showed Cl⁻ transport properties similar to the one from Pokkali. Quantitative PCR analyses revealed higher abundance of OsHKT1;1-FL transcripts in Nipponbare than in Pokkali with markedly lower OsHKT1;1-V2 levels in Pokkali under salt stress. This study provides a new insight into HKT-mediated ion homeostasis under salinity stress. Full article

Interferon-stimulated gene 15 (ISG15) is an interferon-induced ubiquitin-like protein that plays an important role in antiviral defense and inflammatory responses, primarily through the process of ISGylation, whereby ISG15 is covalently conjugated to target proteins. Beyond its intracellular functions, a portion of free unconjugated ISG15 is also released into the extracellular environment during infections and diseases such as cancer. Extracellular ISG15 is known to regulate immune cell activity and cytokine production. Despite its immune-modulatory role, how ISG15 is released from cells has remained unclear. In this study, we have identified a non-lytic mechanism by which human macrophages release ISG15. Using lipopolysaccharide (LPS) as a stimulus, we show that extracellular LPS triggers unconjugated ISG15 release by utilizing plasma membrane-localized Gasdermin D (GSDMD) pores. Mechanistically, LPS via the autocrine/paracrine action of type-I interferon (IFN) activates caspase-4 (Casp4) to cleave the N-terminal domain of GSDMD for the formation of cell surface GSDMD pores that permit the extracellular release of unconjugated ISG15 in the absence of lytic cell death. Together, our studies have identified the IFN-Casp4-GSDMD axis as a previously unrecognized non-classical pathway for unconjugated ISG15 release from cells. Full article

Conventional semen analysis fails to capture the molecular determinants underlying impaired reproductive function. Emerging evidence positions seminal plasma (SP) and extracellular vesicles (EVs) as dynamic regulators of sperm physiology, rather than passive transport components. SP, enriched with proteins, metabolites, hormones, and antioxidants, modulates sperm motility, capacitation, acrosome reaction, and immune tolerance. Complementarily, EVs, including prostasomes, epididymosomes, and testicular vesicles, deliver proteins, lipids, and small RNAs that remodel sperm membranes, protect against oxidative insults, and influence fertilization success. A critical dimension of the SP-EV axis is its role in balancing oxidative stress (OS) and endocrine signaling. Hormones and metabolic regulators within SP, together with EV-mediated transfer of receptors and regulatory RNAs, further integrate systemic metabolic health with local reproductive outcomes. Dysregulation of these networks, particularly in conditions such as varicocele, obesity, diabetes, and idiopathic infertility, compromises sperm function and reduces assisted reproductive technology (ART) success. This evidence-based review synthesizes current evidence on SP and EVs as ‘molecular gatekeepers’ in male infertility, emphasizing OS regulation, endocrine crosstalk, and their potential as biomarker reservoirs. By integrating proteomic, metabolomic, and transcriptomic insights, the translational opportunities for biomarker-informed diagnostics, prognostication, and therapeutic interventions are highlighted. Full article

Background: Black spot disease severely constrains Chinese cabbage production. Methods: To elucidate the defence mechanisms underlying this response, transcriptomic and metabolomic profiles were analysed in leaves of the Chinese cabbage line 904B at 24 h post-inoculation (hpi) with Alternaria brassicicola. In parallel, gene silencing and overexpression were conducted for BraPBL, an RLCK family member in Chinese cabbage. Results: The Chinese cabbage line 904B exhibited marked suppression of cytokinin and auxin signalling, coupled with enhanced expression of genes involved in ethylene and jasmonic acid signalling. Multiple secondary metabolites exhibited differential changes, specifically the sterol compound 4,4-dimethyl-5alpha-cholest-7-en-3beta-ol was significantly upregulated in the treatment group. These metabolites were primarily enriched in the indole alkaloid metabolism and glycerolipid metabolism pathways. Concurrently, BraPBL exhibits increasing expression with prolonged infection. BraPBL overexpression enhances resistance to black spot disease, whereas silencing reduces resistance. Subcellular localization confirmed BraPBL at the plasma membrane. Overexpression of BraPBL upregulates the reactive oxygen species-related gene RBOH and the signal transduction-related gene MEKK1, whilst simultaneously activating the JA pathway. Conclusions: Overall, 904B activates defence-related hormones while suppressing growth and development-related hormones during early infection. Secondary metabolites, particularly the sterol compound 4,4-dimethyl-5alpha-cholest-7-en-3beta-ol, play key roles in defence, and BraPBL functions as a black spot disease–related defence gene in Chinese cabbage. Full article

Exogenous gibberellin (GA₃) significantly improves sugar accumulation in longan (Dimocarpus longan) fruit, yet its molecular mechanism remains unclear. This study demonstrates that 50 mg/L GA₃ optimally enhances sucrose, glucose, fructose, total sugar, and sweetness in longan. Transcriptomic analysis revealed 1345 differentially expressed genes (DEGs), including the sugar transporter gene DlSWEET3a, which was upregulated by GA₃. Subcellular localization confirmed DlSWEET3a resides on the plasma membrane. Functional assays in yeast demonstrated its ability to transport glucose, fructose, mannose, and galactose. Critically, transient overexpression of DlSWEET3a in longan fruit and stable overexpression in tobacco leaves significantly increased soluble sugar content. These results establish that GA₃ promotes sugar accumulation in longan fruit partly through the upregulation of the plasma membrane hexose transporter DlSWEET3a, providing a mechanistic insight into gibberellin-mediated fruit quality improvement. Full article

Signaling mediated by CLAVATA3/EMBRYO SURROUNDING REGION-RELATED (CLE) peptides and their receptors is essential for plants to adapt to abiotic stress. To address the global issue of drought-induced growth inhibition and mortality in poplar (Populus spp.), this study investigated the function of the PtrCLE1A gene from Populus trichocarpa Torr. et Gray in drought tolerance regulation. We employed gene cloning, expression vector construction, and genetic transformation of poplar, combined with bioinformatics analysis, subcellular localization, phenotypic observation, physiological index measurement, and gene expression analysis. The results demonstrated that both PtrCLE1A and PtrCLE1B encode pre-propeptides containing a signal peptide, with an identical mature peptide sequence (RLSPGGPDPRHH), and their putative receptors are PtrCLV1/2. Furthermore, the PtrCLE1A pre-propeptide was localized around the plasma membrane in tobacco (Nicotiana benthamiana Domin) mesophyll cells, consistent with its predicted function. PtrCLE1A and PtrCLE1B are primarily expressed in the roots and xylem of P. trichocarpa. Additionally, only the PtrCLE1A promoter contained drought-responsive cis-elements, and its expression was induced by drought stress in root, xylem, and leaf tissues of P. trichocarpa. Overexpression of the PtrCLE1A gene in Populus tomentosa Carrière (triploid) significantly increased adventitious root length under osmotic stress. Overexpression lines exhibited 22.00% to 22.92% longer adventitious roots than EV lines at 50/100 mM mannitol, and 65.12% to 73.17% longer at 150 mM mannitol. The OE lines also exhibited higher photosynthetic capacity and instantaneous water use efficiency (iWUE), along with reduced membrane damage under drought conditions, indicating enhanced drought resistance. This study provides new genetic resources and a theoretical foundation for molecular breeding of drought-tolerant poplar. Full article

In mammals, CD22 is a member of the Siglec family and plays essential roles in B-cell activation, signal transduction, and immune regulation. However, its functions in teleost fish remain largely unclear. In this study, a CD22 homolog designated On-CD22 was identified and cloned from Nile tilapia (Oreochromis niloticus). On-CD22 transcripts were highly expressed in the head kidney and peripheral blood of healthy fish and showed significant expression changes following infection with Streptococcus agalactiae, Aeromonas hydrophila, or stimulation with poly(I:C). Subcellular localization analysis indicated that On-CD22 is predominantly localized to the plasma membrane. Luciferase reporter assays performed in heterologous cell systems showed that overexpression of On-CD22 was associated with changes in the basal transcriptional activities of NF-κB, IFN1, IFN3, and STAT1 responsive promoters under unstimulated conditions. Furthermore, single-cell transcriptomic analysis revealed that On-CD22 expression was mainly confined to the B-cell population within head-kidney leukocytes. Collectively, these findings suggest that On-CD22 may be involved in immune regulatory processes in Nile tilapia. Full article

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), poses a severe threat to global wheat production. The adaptor protein complex AP-1 plays a crucial role in vesicular trafficking, yet its function in rust fungi remains poorly understood. In this study, a gene encoding an AP-1 σ subunit, designated PsAP1, was identified in Pst. The expression of PsAP1 was highly induced during the early infection stage. Heterologous expression of PsAP1 in a Fusarium graminearum mutant partially restored its pathogenic defects. Subcellular localization analysis revealed that PsAP1 localizes to the plasma membrane, cytoplasm, and nucleus. Silencing PsAP1 in wheat using Barley stripe mosaic virus-mediated host-induced gene silencing (BSMV-HIGS) significantly attenuated Pst pathogenicity, reducing hyphal growth by 6.7% (colony diameter), sporulation by 61.6% (lesion length), and pathogen biomass by 66%, along with enhanced accumulation of host reactive oxygen species. Transcriptomic analysis further demonstrated that silencing PsAP1 disrupted multiple pathways, including MAPK signaling, glutathione metabolism, and carbohydrate metabolism. These findings indicate that PsAP1 facilitates Pst infection by modulating vesicular trafficking, suppressing host immunity, and reprogramming host metabolism. This study provides novel insights into the pathogenic mechanisms of rust fungi and suggests a potential target for disease control. Full article

The anti-aging gene/protein Klotho (Kl), most present in kidneys, has been well studied in mice (mKl), but not in rats (rKl). This study investigated the renal rKl expression in male and female rats. Sex-related measurement of rKl-controlled electrolytes was performed in plasma/urine samples, as were tests on species differences in renal Kl expression (rats vs. mice). rKl mRNA/protein expression was studied by qRT-PCR/Western-blotting in renal total RNA/cell membranes and its localization by immunofluorescence microscopy. Urine/plasma ions (phosphate/total calcium) and macroelements (phosphorus/calcium) were measured biochemically and by ICP-MS, respectively. In rat kidneys, the rKl mRNA/protein was detected in the cortex, outer and inner stripe but not in the papilla, and was immunolocalized in the basolateral membrane of proximal tubules in the cortex and outer stripe, but not in the intercalating cells of the cortical distal tubules, whereas mKl was observed in the mouse kidney cortex but not the outer stripe. Female-dominant expression of renal rKl, affected by androgen’s inhibitory effect, may have contributed to the sex-related level of urine electrolytes, particularly phosphates. Renal mKl expression was male-dominant. Sex- and species-related differences in renal Kl expression may be relevant for the selection of the sex and/or the model organism in studies addressing aging/mineral homeostasis. Full article

The interplay between phosphate (Pi) signaling and defense pathways is crucial for plant fitness, yet its molecular basis, particularly in wheat, remains poorly understood. Here, we functionally characterized the plasma membrane-localized high-affinity phosphate transporter TaPT3-2D and demonstrated its essential roles in Pi uptake, arbuscular mycorrhizal (AM) symbiosis, and fungal disease resistance. Quantitative analyses showed that TaPT3-2D expression was strongly induced by AM colonization (165-fold increase) and by infection with Bipolaris sorokiniana (54-fold increase) and Gaeumannomyces tritici (15-fold increase). In contrast, virus-induced gene silencing (VIGS) of TaPT3-2D reduced Pi uptake and mycorrhizal colonization. Moreover, TaPT3-2D-silenced plants exhibited increased susceptibility to biotrophic, hemibiotrophic, and necrotrophic fungi, accompanied by reduced expression of pathogen-related genes. The simultaneous impairment of Pi uptake, AM symbiosis, and defense responses in silenced plants indicates that TaPT3-2D functionally couples these processes. Functional complementation assays in low-Pi medium further revealed that TaPT3-2D partially rescued defective Pi uptake in mutant MB192 yeast, supporting its role as a high-affinity phosphate transporter. Collectively, these results identify TaPT3-2D as both a key regulator of individual pathways and as a molecular link connecting Pi homeostasis, symbiotic signaling, and disease resistance in wheat. Full article

Longan (Dimocarpus longan Lour.) is a commercially valuable tropical fruit crop that contains two antagonistic FLOWERING LOCUS T (FT) homologs involved in regulating flowering time. However, how these FT genes interact with flowering regulators FLOWERING LOCUS D (FD) and APETALA1 (AP1) remains unknown. Four flowering-related genes in longan, DlFT1, DlFT2, DlAP1 and DlFD, were successfully isolated. Expression profiling revealed that all four genes were expressed in leaves and buds across different stages of natural and KClO₃-induced floral bud differentiation. Functional characterization through heterologous overexpression in Arabidopsis thaliana showed that DlAP1 significantly promotes early flowering under long-day conditions and induced morphological changes in floral organs and leaves. In contrast, DlFD overexpression had no effect on flowering time. Subcellular localization assays revealed that DlFT1 and DlFT2 localized to both the nucleus and the plasma membrane, while DlAP1 and DlFD localized exclusively to the nucleus. Yeast two-hybrid and bimolecular fluorescence complementation (BiFC) analyses revealed a novel regulatory node: DlFT1 directly interacts with DlAP1, a finding that expands the classical FT-FD-AP1 flowering model. Additionally, DlFD interacts more strongly with DlFT1 than with DlFT2, whereas DlFT1 only interacts with DlAP1, but not DlFT2. These results demonstrate that DlFT1 promotes flowering not only via the conserved FD-dependent pathway but also through direct association with AP1. These findings advance our understanding of the regulatory mechanisms of flowering in longan and provide valuable insights into flowering pathways of perennial woody species. Full article

Cell membrane receptors play key roles in physiological and pathological processes, yet the mechanisms governing their expression and distribution across the plasma membrane remain not completely understood. Broadly, membrane receptors can be categorized into phasic and tonic receptors. Tonic GABA-A receptors have attracted considerable interest due to their distinct molecular composition and their capacity to mediate highly sensitive, sustained inhibitory responses in the presence of ambient GABA. Traditionally, these receptors have been described as residing in peri- and extrasynaptic regions, where they are thought to sense GABA spillover and generate tonic inhibition. However, evidence accumulated over several decades has challenged this canonical view. Multiple studies have reported activity-dependent and pathology-associated relocalization of tonic GABA-A receptor subunits from their typical peri- and extrasynaptic domains into the synaptic cleft. This phenomenon has been documented in both in vivo and in vitro models, yet major questions remain regarding its occurrence, underlying mechanisms, functional significance, and adaptive value. This review synthesizes current evidence and highlights ongoing controversies surrounding the ultrastructural localization of tonic GABA-A receptors. Based on an exhaustive search of the PubMed database, this review summarizes key findings from studies investigating the subcellular distribution of these receptors and discusses emerging perspectives on their potential synaptic presence. Full article

Background/Objectives: We evaluated Goreisan, a traditional Chinese medicine, for its effects on nephrotic syndrome in a rat model. Methods: Male Sprague–Dawley rats underwent right nephrectomy at 5 weeks of age, followed by adriamycin administration (5 mg/kg) at 6 and 8 weeks of age to induce nephrotic syndrome. At 10 weeks, rats were divided into three groups: vehicle (control), Goreisan 0.5 g/kg (GL), and Goreisan 1.0 g/kg (GH). Goreisan was administered daily for 4 weeks. At 14 weeks, blood, urine, mRNA expressions, and kidney histopathology were analyzed. Data were analyzed using one-way ANOVA followed by Tukey–Kramer post hoc testing. Results: Goreisan prevented worsening kidney function, with reduced glomerular and tubulointerstitial damage, lower systemic and intrarenal 8-hydroxy-2′-deoxyguanosine levels, and lower plasma aldosterone levels and expression of intrarenal renin–angiotensin–aldosterone system (RAAS)-related factors. Urine volume significantly increased in GL and GH groups compared with the control group. In the GH group, urine volume increased markedly (Δ urine volume: 10.0 ± 2.6 mL/day), whereas it tended to decrease in the Vehicle group (Δ urine volume: −1.3 ± 2.5 mL/day). Urine osmolality was lower in the GH group, with a larger decrease in Δ urine osmolality (−616.3 ± 132.8 mOsm/L). These changes occurred without an increase in urinary sodium excretion, suggesting an aquaretic effect independent of natriuresis. Creatinine clearance (CCr/kg) declined markedly in the Vehicle group but was significantly preserved in the GH group (Δ CCr/kg: −2.2 ± 0.19 vs. −0.7 ± 0.28), indicating renoprotective effects. No differences were found in serum arginine–vasopressin levels. Real-time PCR and immunohistochemical staining showed no significant differences in aquaporin (AQP) mRNA expression (AQP1, AQP2, AQP3, and AQP4), but AQP2 localization to the apical membrane in the collecting ducts was reduced with Goreisan treatment. Conclusions: Goreisan demonstrates kidney-protective and diuretic effects in nephrotic syndrome, potentially through reducing systemic oxidative stress, modulating RAAS activation, and altering AQP2 trafficking. Full article

Ratoon rice cultivation is an efficient production system that achieves a second harvest from the stubble of the main crop, but its yield potential is largely constrained by variation in axillary bud regeneration capacity. Here, we identify OsPM19L, a plasma membrane–localized AWPM-19 domain protein, as a key regulator of rice ratooning ability. Transcriptome analysis revealed higher OsPM19L expression in strong-regeneration cultivars, followed by a sharp decline after harvest. Promoter assays and hormonal treatments demonstrated that OsPM19L is strongly induced by ABA and functions as a positive regulator in ABA signaling. Under field conditions, ospm19l mutants exhibited increased tiller number but reduced ratooning index, whereas OsPM19L-OE plants showed the opposite pattern, indicating stage-specific regulation of tillering and regeneration. Hormone profiling and gene expression analyses showed that OsPM19L is associated with altered levels of multiple phytohormones in regenerating axillary buds, showing higher CK and GA levels and lower IAA and ABA levels in OsPM19L-OE compared with the wild type. Consequently, OsPM19L appears to facilitate dormancy release and enhance early axillary bud growth during the ratoon season. These findings indicate OsPM19L may act as a central regulator linking ABA signaling with hormonal cross-talk, providing new insights into the molecular control of regeneration and potential targets for improving ratoon rice productivity. Full article