Search Results (740)

Soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins play evolutionarily conserved roles in intracellular vesicle trafficking and membrane fusion across eukaryotes. In pathogenic fungi, various SNARE homologs have been shown to critically regulate host infection processes. Here, we characterize the functional roles of CfSec22 in the sweet potato black rot pathogen Ceratocystis fimbriata. Phylogenetic and domain analyses demonstrate that CfSec22 shares homology with Sec22 proteins from Saccharomyces cerevisiae (ScSec22), Magnaporthe oryzae (MoSec22), and other fungi, containing both the characteristic Longin homology domain and V-SNARE domain. Functional studies reveal that CfSec22 regulates growth, conidiation, and virulence of C. fimbriata. Deletion of CfSEC22 resulted in abnormal vacuole morphology and impaired endocytosis. The ΔCfsec22 mutant displayed heightened sensitivity to diverse stress conditions: oxidative, endoplasmic reticulum, and cell wall stressors. Subcellular localization studies confirmed the endoplasmic reticulum residence of CfSec22. Finally, we established that CfSec22 regulates the secretion of virulence-associated proteins and is required for the induction of ipomeamarone in infected sweet potato tissues. Together, our findings demonstrate that CfSec22-mediated vesicle trafficking serves as a critical regulatory mechanism supporting growth, conidiogenesis, and pathogenicity in C. fimbriata. Full article

Endocrine cells are dedicated to the production and processing of hormones, from peptides to small molecules, to regulate key physiological processes, including glucose homeostasis and metabolism. Because of this relatively high productivity, endocrine cells must handle a variety of stresses from oxidative stress to the unfolded protein response of the endoplasmic reticulum (UPR^ER). While much is known about the major pathways regulating the UPR^ER, the roles of endocrine cell type-specific, context-dependent, and time-dependent transcriptional changes are not well explored. To identify unique and shared responses to the UPR^ER across a subset of endocrine cell types, we tested representative lines for β-cells (insulin), α-cells (glucagon), δ-cells (somatostatin), X/A-cells (ghrelin), L-cells (glucagon-like peptide 1 (GLP1)), and thyrotropes (thyroid hormone and thyroglobulin). We exposed each cell type to the canonical ER stressor thapsigargin for 6 and 24 h, or vehicle for 24 h, and performed mRNA sequencing. Analysis of the data showed all lines responded to thapsigargin. Comparisons of differentially expressed genes between each line revealed both shared and unique transcriptional signatures. These data represent a valuable mineable set of candidate genes that may have cell type-specific functions during the UPR^ER and have the potential to lead to a new understanding of how different endocrine cells mitigate or succumb to ER stress. Full article

Porcine rotavirus (PoRV) is one of the most devastating enteric pathogens causing gastroenteritis in pigs, particularly the sudden occurrence in recent years in China. To elucidate host–pathogen interactions and molecular mechanisms underlying PoRV pathogenesis, four-dimensional (4D) data-independent acquisition (DIA) proteomic (4D-DIA) analysis was performed to comprehensively quantify the differentially abundant proteins (DAPs) in PoRV-infected IPEC-J2 cells. A total of 8725 cellular proteins were identified with 279 more abundant and 356 down abundant proteins. A Western blot showed that the abundance of SA100A8, DAPK2, and FTL were in accordance with the acquired proteomic data using 4D-DIA analysis. Bioinformatics analyses of GO and KEGG demonstrated that various DAPs are involved in crucial biological processes and signaling pathways, such as immune response, signal transduction, metabolic pathways, autophagy, endoplasmic reticulum (ER) stress, and mitochondrial dysfunction. Notably, inflammatory features of host response upon PoRV infection were highlighted, with RT-qPCR confirming the significant upregulation of IL-1α, IL-6, IL-8, TNF-α, STAT1, and IRF9 transcript levels during infection. Altogether, our preliminary findings advance our understanding of PoRV pathogenesis and may shed light on identifying potential targets for the prevention and control of PoRV-associated gastroenteritis. Full article

Anthocyanins are key antioxidants that play a significant role in plant responses to adverse stresses, including nitrogen deficiency. However, research on the metabolic and transcriptional regulation of anthocyanins in black soybean seed coats under low-nitrogen conditions remains limited. Here, we report that low-nitrogen treatment significantly alters the accumulation of anthocyanin metabolites and the gene expression profiles in black soybeans. Specifically, a greater number of differential anthocyanin metabolites are induced under low-nitrogen conditions, which contributes to the accumulation of anthocyanins in the seed coat. GO and KEGG enrichment analyses revealed that the differentially expressed genes (DEGs) are mainly enriched in multiple antioxidant pathways involved in responding to low-nitrogen stress; in flavonoid and phenylalanine metabolic pathways, as well as protein processing in endoplasmic reticulum, which are associated with anthocyanin biosynthesis; and in plant hormone signal transduction pathways involved in the regulation of anthocyanin accumulation. The expressions of genes encoding key enzymes in anthocyanin biosynthesis, such as dihydroflavonol 4-reductase (DFR) and O-methyltransferase (OMT), as well as genes encoding the blue light photoreceptor cryptochrome (CRY) and proteins related to cellular autophagy, were upregulated under low-nitrogen treatment. This suggests that these genes may play a key role in low-nitrogen-induced anthocyanin accumulation. This study provides a theoretical basis and novel perspective for understanding the regulatory mechanism underlying low-nitrogen-induced anthocyanin accumulation in black soybeans. Full article

Rhabdomyolysis is a severe condition that commonly leads to acute kidney injury (AKI), with limited targeted treatments for rhabdomyolysis-induced AKI (RIAKI) adding to the challenge. Emerging evidence implicates nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 4 (NOX4) in the pathological processes of various kidney diseases, but its role in RIAKI remains unclear. We applied renal tubular epithelial cell (RTEC)-specific NOX4 knockout and the NOX4 inhibitor GKT137831 to treat RIAKI in vivo and in vitro. We found that genetic and pharmacological inhibition of NOX4 protected against glycerol-induced renal dysfunction, mitigated inflammatory responses and attenuated apoptotic rates. Additionally, NOX4 blockade suppressed the accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA), and enhanced the activities of antioxidant enzymes. Furthermore, NOX4 inhibition reduced the expression of endoplasmic reticulum stress (ERS)-associated proteins at both the RNA and protein levels. Collectively, these findings demonstrate that genetic and pharmacological suppression of NOX4 protects against RIAKI by reducing ROS generation, boosting antioxidant defense and inhibiting ERS activation. NOX4 inhibition may offer a potential approach for developing new treatment options for RIAKI. Full article

Background: Argas persicus is a hematophagous ectoparasite of poultry and is the vector of several agents infectious to poultry. This study aims to explore the key genes affecting the ovarian development of A. persicus. Methods: RNA-seq was performed on the ovaries of A. persicus before blood-feeding, on the day of engorgement, and 6 days post-engorgement. Utilizing the threshold padj < 0.05 and|log₂(foldchange)| > 1, differentially expressed genes were identified, and hub genes were determined by constructing protein–protein interaction (PPI) networks. Results: A total of 1008 differentially expressed genes were obtained during the feeding period, including 448 up-regulated and 560 down-regulated genes. Further, 2179 differentially expressed genes were screened in the preoviposition stage, including 1957 up-regulated and 222 down-regulated genes. These genes are mainly annotated in functions such as peptidase activity (especially serine protease activity), protein folding, protein assembly, and cell component assembly, and enriched in pathways such as protein processing in endoplasmic reticulum, lysosome, glutathione metabolism, and sphingolipid metabolism. In addition, some proteins that are closely related to ovarian development, including heat shock protein 70, protein disulfide isomerase, paramyosin, troponin I, hexosaminidase, serine protease, Kunitz serine protease inhibitors, and vitellogenin, were obtained. Conclusions: These findings fill the gap in the biological data for the ovarian development of soft ticks, provide a reference database for subsequent proteomics research, and offer fundamental support for the screening and development of candidate antigens for anti-tick vaccines. Full article

In human cells, the biogenesis of membrane proteins, which account for one quarter of polypeptides and sixty percent of human drug targets, is initiated at the membrane of the endoplasmic reticulum (ER). This process involves N-terminal signal peptides or transmembrane helices in the membrane protein precursors. Over one hundred proteins enable membrane-targeting and -insertion of the precursors as well as their folding and covalent modifications. Four targeting pathways to the Sec61 channel in the ER membrane with their effectors and three cooperating or independent membrane protein–insertases have been identified. We combined knock-down of individual components of these pathways and insertases in HeLa cells with label-free quantitative mass spectrometric analysis of the proteomes. Differential protein abundance analysis in comparison to control cells was employed to identify clients of components involved in the targeting or membrane insertion of precursors. Alternatively, knock-out cells or relevant patient fibroblasts were employed. The features of the client polypeptides were characterized to identify the client types of the different components and, ideally, their rules of engagement. In this review/article-hybrid, the focus is on global lessons from and limitations of the proteomic approach in answering the cell biological question, as well as on new aspects, such as N-terminal acetylation of membrane protein precursors. Full article

Fluorescence microscopy performance can be significantly enhanced with image post-processing algorithms, particularly deconvolution techniques. These methods aim to revert optical aberrations by deconvolving the image with the point spread function (PSF) of the microscope. However, analytical deconvolution algorithms are computationally demanding, time-consuming, and require precise PSF estimation and careful parameter selection for optimal results. This paper introduces NeuroDecon, a neural network-based method for volumetric deconvolution of confocal images with residual blocks and U-net based architecture. NeuroDecon employs a training strategy that implicitly incorporates the experimental PSF, which acts as a “fingerprint” of system aberrations. This open-source approach allows for personalized training dataset generation, enabling its wide usage for various applications, reduces imaging artifacts and improves computational efficiency. NeuroDecon network outperforms analytical deconvolution methods in image restoration, resolution, and signal-to-noise ratio enhancement and facilitates further data analysis with methods based on automatic segmentation, including protein cluster detection, endoplasmic reticulum network, and dendritic spine 3D-morphology analysis. Full article

Follicular development is recognized as a highly complex biological process regulated by multiple factors. Thyroid hormone (TH) is considered one of the key regulators of female reproduction, and its dysregulation can significantly impair follicular development. Epigallocatechin gallate (EGCG), the main active component of green tea, possesses strong antioxidant properties. Numerous studies have demonstrated that EGCG positively influences reproductive function in both humans and animals. However, whether EGCG directly affects follicular development under conditions of TH dysregulation remains poorly understood. The primary objective of this study was to investigate the impact of hyperthyroidism on ovarian development, examine whether EGCG could mitigate the adverse effects of TH dysregulation, and elucidate the underlying molecular mechanisms. In the T₄-induced hyperthyroidism rat model, ovarian tissues were serially sectioned for Hematoxylin-Eosin (HE) and Masson’s trichrome staining to assess morphological changes, and follicle numbers were quantified at each developmental stage. Granulosa cell (GC) viability, proliferation, and apoptosis induced by T₃ were evaluated using CCK8, EdU, and TUNEL assays, respectively. Antioxidant enzyme activity was measured, and the expression levels of related proteins were analyzed via Western blotting. Results showed that hyperthyroidism altered ovarian structure, significantly increasing the number of atretic follicles. Levels of antioxidant enzymes, including Superoxide Dismutase (SOD), Glutathione Peroxidase (GSH-PX), and Catalase (CAT), were markedly decreased, whereas the lipid peroxidation product malondialdehyde (MDA) was significantly elevated. Furthermore, all ERS-related proteins, phosphorylated Eukaryotic Initiation Factor 2 Alpha (p-eIF2α), Activating Transcription Factor 4 (ATF4), C/EBP homologous protein (CHOP), and Caspase-3, were upregulated, accompanied by decreased glucose-regulated protein 78 (GRP78) expression. Treatment with EGCG alleviated these detrimental effects of hyperthyroidism. At the cellular level, high concentrations of T₃ reduced GC viability and proliferation while increasing apoptosis. Reactive oxygen species levels were elevated, and GRP78 expression was decreased. Notably, all T₃-induced effects were reversed by EGCG treatment. In summary, this study demonstrates that hyperthyroidism induces oxidative stress in GCs, which triggers endoplasmic reticulum stress via the eIF2α/ATF4 pathway and leads to apoptosis. EGCG mitigates apoptosis by enhancing antioxidant capacity, thereby preserving ovarian function. These findings establish EGCG as a protective agent for maintaining ovarian health and fertility. Full article

Background/Objectives: Recent evidence challenges the classical chemiosmotic theory, suggesting that proton movement along membrane surfaces—not bulk-phase gradients—drives bioenergetic processes. Proton accumulation on membranes like the myelin sheath and endoplasmic reticulum (ER) may represent a universal mechanism for cellular energy storage. This study investigates whether phospholipids from these membranes, combined with anionic bee venom proteins, enhance proton absorption, potentially elucidating a novel bioenergetic pathway. Methods: Five phospholipids (phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, sphingomyelin, phosphatidylcholine) from rat liver were isolated to model myelin/ER membranes. Anionic proteins (pI 5.65–5.80) were purified from bee venom via cation exchange chromatography. Liposomes (with/without proteins) were prepared, and proton absorption was quantified by pH changes in suspensions versus pure water. Statistical significance was assessed via ANOVA and t-tests. Results: All phospholipid liposomes examined in this study absorbed protons under the tested conditions, with phosphatidylethanolamine showing the highest capacity (pH increase: 7.00 → 7.18). Liposomes enriched with anionic proteins exhibited significantly greater proton absorption (e.g., phosphatidylserine + proteins: pH 8.15 vs. 7.15 alone; p < 2.43 × 10⁻⁶). Sphingomyelin-protein liposomes absorbed the most protons, suggesting that protein–phospholipid interactions modulate surface proton affinity. Conclusions: Anionic bee venom proteins amplify proton absorption by phospholipid membranes, supporting the hypothesis that lipid–protein complexes act as “proton capacitors”. This mechanism may underpin extramitochondrial energy storage in myelin and ER. Pharmacologically, targeting these interactions could mitigate bioenergetic deficits in aging or disease. Further research should define the structural basis of proton capture by membrane-anchored proteins. Full article

Obesity-induced insulin resistance and type 2 diabetes mellitus (T2DM) represent complex systemic disorders marked by chronic inflammation, oxidative stress, mitochondrial dysfunction, and endoplasmic reticulum (ER) stress. These pathophysiological processes disrupt insulin signaling and β-cell function, leading to impaired glucose homeostasis across multiple organs. Conventional therapies often target isolated pathways, overlooking the intricate molecular crosstalk and organelle-level disturbances driving disease progression. Citrus-derived polyphenols—including hesperidin, naringenin, nobiletin, and tangeretin—have emerged as promising agents capable of orchestrating a multi-targeted “metabolic reprogramming.” These compounds modulate key signaling pathways, including AMPK, PI3K/Akt, NF-κB, and Nrf2, thereby enhancing insulin sensitivity, reducing pro-inflammatory cytokine expression, and restoring redox balance. Furthermore, they improve mitochondrial biogenesis, stabilize membrane potential, and alleviate ER stress by modulating the unfolded protein response (UPR), thus supporting cellular energy homeostasis and protein folding capacity. Evidence from preclinical studies and select clinical trials suggests that citrus polyphenols can significantly improve glycemic control, reduce oxidative and inflammatory markers, and preserve β-cell function. Their pleiotropic actions across molecular and organ-level targets position them as integrative metabolic modulators. This review presents a systems-level synthesis of how citrus polyphenols rewire metabolic signaling networks and organelle resilience, offering a holistic therapeutic strategy to mitigate the root causes of obesity-induced insulin resistance. Full article

Parasitoids exhibit remarkable abilities to manipulate host physiology, ensuring offspring survival and development. This study investigated the molecular mechanisms underlying how the parasitoid Cotesia chilonis modulates cold tolerance in its host, the rice stem borer Chilo suppressalis, using transcriptome sequencing. We found that the host larvae’s supercooling point was lowest at 3 days post-parasitism but increased significantly by day 4. Transcriptome analysis identified 507 differentially expressed genes (DEGs), including 235 up-regulated by parasitism. Functional enrichment revealed that these DEGs were primarily associated with ribosome biogenesis, protein processing in the endoplasmic reticulum (ER), and oxidative phosphorylation under parasitism stress. Notably, 24 DEGs linked to temperature tolerance were predominantly heat shock proteins (HSPs) and calcium signaling-related genes. The reliability of transcriptome data was confirmed via RT-qPCR for eight randomly selected DEGs. Functional assays demonstrated that parasitism stress significantly inhibited ER activity. However, HSP expression did not significantly affect ER activity or cytosolic Ca²⁺ concentration in the hemolymph cells of C. suppressalis larvae. This research provides insights into the complex physiological and molecular mechanisms through which C. suppressalis responds to parasitism stress, particularly concerning cold tolerance modulation. Full article

Mitochondria-associated membranes (MAMs) are essential for cellular homeostasis. MAMs are specialized contact sites located between the endoplasmic reticulum (ER) and mitochondria and control apoptotic pathways, lipid metabolism, autophagy initiation, and calcium signaling, processes critical to the survival and function of neurons. Although this area of membrane biology remains understudied, increasing evidence links MAM dysfunction to the etiology of major neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis (ALS). MAMs consist of a network of protein complexes that mediate molecular exchange and ER–mitochondria tethering. MAMs regulate lipid flow in the brain, including phosphatidylserine and cholesterol; disruption of this process causes membrane instability and impaired synaptic function. Inositol 1,4,5-trisphosphate receptor—voltage-dependent anion channel 1 (IP3R-VDAC1) interactions at MAMs maintain calcium homeostasis, which is required for mitochondria to produce ATP; dysregulation promotes oxidative stress and neuronal death. An effective therapeutic approach for altering neurodegenerative processes is to restore the functional integrity of MAMs. Improving cell-to-cell interactions and modulating MAM-associated proteins may contribute to the restoration of calcium homeostasis and lipid metabolism, both of which are key for neuronal protection. MAMs significantly contribute to the progression of neurodegenerative diseases, making them promising targets for future therapeutic research. This review emphasizes the increasing importance of MAMs in the study of neurodegeneration and their potential as novel targets for membrane-based therapeutic interventions. Full article

Polystyrene microplastic (MP) and its co-existing contaminants may exert different toxic effects on its surrounding aquatic organisms. In order to detect the intestinal harmful responses, tilapia were subjected to exposure with 75 nm of MPs, 100 ng·L⁻¹ of sulfamethoxazole (SMZ), 5 ng·L⁻¹ of BDE153, and combinations thereof over periods of 2, 4, and 8 days. Enzymatic assays, transcriptomics, proteomics, and metabolomics were employed to evaluate intestinal histopathological effects. Results showed that significant reductions were observed in ATP, ROS, SOD, EROD, lipid metabolism-related enzymes, pro-inflammatory cytokines (TNFα and IL-1β), and apoptosis marker caspase 3 across all groups at day 8. Histological evaluation revealed diminished goblet cell density, with distinct vacuole formation in the BDE153+MPs group. KEGG pathway analysis highlighted disruptions in endocytosis, MAPK signaling, phagosome formation, and actin cytoskeleton regulation. Proteomic findings indicated notable enrichment in endocytosis (decreased sorting nexin-2; increased Si:dkey-13a21.4), MAPK/PPAR signaling, protein processing in the endoplasmic reticulum (Sec61 subunit gamma), and cytoskeletal modulation (reduced fibronectin; elevated activation peptide fragment 1), with or without SMZ and BDE153. Metabolomic profiling showed significant alterations in ABC transporters, aminoacyl-tRNA biosynthesis, protein digestion and absorption, and linoleic acid metabolism. In summary, these findings suggest that BDE153 and MPs synergistically exacerbate intestinal damage and gene/protein expression over time, while SMZ appears to exert an antagonistic, mitigating effect. Full article

Background: Chinese Red Steppe cattle (CRS) combine indigenous environmental resilience with moderate dairy performance, whereas Holstein cattle (HOL), despite their high milk yield, suffer reduced genetic diversity and compromised adaptation. A comparative analysis of their population genetic architecture and selection signatures can reveal valuable targets for CRS dairy improvement. Methods: We genotyped 61 CRS and 392 HOL individuals using the Illumina GGP Bovine 100K SNP array and performed stringent quality control. Population structure was assessed via principal component analysis, neighbor-joining trees, and sparse nonnegative matrix factorization. Historical effective population size (Ne) and divergence time were inferred with SMC++. Genome-wide selection scans combined Fixation Index (FST) and Cross-Population Composite Likelihood Ratio test (XP-CLR); overlapping high-confidence regions were annotated and subjected to GO and KEGG enrichment analyses. Results: CRS and HOL were clearly separated along PC1 (explaining 57.48% of variance), with CRS exhibiting high internal homogeneity and weak substructure, versus greater diversity and complex substructure in HOL. SMC++ indicated a split approximately 3500 years ago (700 generations) and a pronounced recent decline in Ne for both breeds. Joint selection mapping identified 767 candidate genes; notably, the ACSM1/2B/3/4 cluster on chromosome 25—key to butanoate metabolism—showed the strongest signal. Enrichment analyses highlighted roles for proteasome function, endoplasmic reticulum stress response, ion homeostasis, and RNA processing in regulating milk fat synthesis and protein secretion. Conclusion: This study delineates the genetic divergence and demographic history of CRS and HOL, and pinpoints core genes and pathways—particularly those governing butanoate metabolism and protein quality control—underlying dairy traits. These findings furnish molecular markers and theoretical guidance for precision breeding and sustainable utilization of Chinese Red Steppe cattle. Full article