Search Results (3,221)

The flavivirus NS1 protein is a component of the viral replication complex and plays diverse, yet poorly understood, roles in the viral life cycle. To enable real-time visualization of the developing replication organelle and biochemical analysis of tagged NS1 and its interacting partners, we engineered a replication-competent yellow fever virus (YFV) replicon encoding a C-terminal fusion of NS1 with green fluorescent protein (NS1–GFP). The initial variant was non-viable in the absence of trans-complementation with wild-type NS1; however, viability was partially restored through the introduction of co-adaptive mutations in GFP (Q204R/A206V) and NS4A (M108L). Subsequent cell culture adaptation generated a 17-nucleotide frameshift within the NS1–GFP linker, resulting in a more flexible and less hydrophobic linker sequence. The optimized genome, in the form of a replicon, replicates in packaging cells that produce YFV structural proteins, as well as in naive BHK-21 cells. In the packaging cells, the adapted NS1–GFP replicon produces titers of infectious particles of approximately 10^6 FFU/mL and is genetically stable over five passages. The expressed NS1–GFP fusion protein localizes to the endoplasmic reticulum and co-fractionates with detergent-resistant heavy membranes, a hallmark of flavivirus replication organelles. This NS1–GFP replicon provides a novel platform for studying NS1 functions and can be further adapted for proximity-labeling strategies aimed at identifying the still-unknown protease responsible for NS1–NS2A cleavage. Full article

Mitochondria are essential organelles involved in metabolism, energy production, and cell signaling. Assessing mitochondrial morphology is key to tracking cell metabolic activity and function. Quantifying these structural changes may also provide critical insights into disease pathogenesis and therapeutic responses. This work details the development and validation of a novel, quantitative image analysis pipeline for the characterization and classification of dynamic mitochondrial morphologies. Utilizing high-resolution confocal microscopy, the pipeline integrates first-order statistics (FOS) and a comprehensive suite of gray-level texture analyses, including gray level co-occurrence matrix (GLCM), gray level run length matrix (GLRLM), gray level dependence matrix (GLDM), gray level size zone matrix (GLSZM), and neighboring gray tone difference matrix (NGTDM) with machine learning approaches. The method’s efficacy in objectively differentiating key mitochondrial structures—fibers, puncta, and rods—which are critical indicators of cellular metabolic and activation states is demonstrated. Our open-source pipeline provides robust quantitative metrics for characterizing mitochondrial variation. Full article

Background/Objective: The primary cilium is the sensory organelle of a cell and a dynamic membrane protrusion during the cell cycle. It originates from the centriole at G₀/G₁ and undergoes disassembly to release centrioles for spindle formation before a cell enters mitosis, thereby serving as a cell cycle checkpoint. Cancer cells that undergo rapid cell cycle and replication have a low ciliation rate. In this study, we aimed to identify cilia-promoting drugs that can accelerate ciliation and decelerate replication of cancer cells. Methods: To perform a comprehensive and efficient literature search on drugs that can promote ciliation, we developed an intelligent process that integrates either the GPT 4 Turbo, Gemini 1.5 Pro, or Claude 3.5 Haiku application programming interfaces (APIs) into a PubMed scraper that we coded, enabling the large language models (LLMs) to directly query articles for predefined user questions. We evaluated the performance of this intelligent literature search based on metrics and tested the effect of two candidate drugs on ciliation and proliferation of medulloblastoma cells. Results: Gemini was the best model overall, as it balanced high accuracy with solid precision and recall scores. Among the top candidate drugs identified are Alvocidib and Alisertib, small-molecule inhibitors of CILK1 and AURKA, respectively. Here, we show that both kinase inhibitors can effectively increase cilia frequency and significantly decrease the replication of medulloblastoma cells. Conclusions: The results demonstrated the potential of using cilia-promoting drugs, such as Alvocidib and Alisertib, to suppress cancer cell replication. Additionally, it shows the massive benefits of integrating accessible large language models to conduct sweeping, rapid, and accurate literature searches. Full article

Chaperone-mediated autophagy (CMA) is a selective lysosomal degradation pathway that relies on the molecular chaperone heat shock cognate 70 kDa protein (HSC70) and the lysosomal receptor LAMP-2A. By recognizing substrate proteins containing KFERQ-like pentapeptide motif, CMA plays a central role in multiple infectious contexts. In host defense and cellular homeostasis, CMA contributes to organelle quality control by selectively degrading damaged or misfolded proteins, including stress- or organelle-associated substrates, thereby limiting pathogen replication while mitigating infection-induced stress and preserving cellular function. Although its detailed mechanisms remain incompletely defined, CMA is thought to involve coordinated steps in which molecular chaperones recognize specific target sequences, recruit autophagy-related components, and deliver substrates for lysosomal translocation and degradation. Recent studies have revealed substantial progress in understanding CMA during viral, bacterial, and fungal infections, identifying key regulatory nodes and signaling pathways. These advances underscore the therapeutic potential of CMA-targeted strategies, such as stabilizing LAMP-2A or enhancing HSC70-mediated substrate recognition. However, the spatiotemporal specificity of CMA’s pro- or antiviral effects remains a major challenge for clinical translation. This review summarizes current progress in this emerging field and highlights unresolved questions, particularly whether tissue- or cell-type-specific regulation of CMA occurs during infection and how precise modulation of CMA activity might achieve optimal anti-infective outcomes. Full article

Calcium (Ca) and selenium (Se) are garnering growing interest because of their capacity to boost crop yields and minimize cadmium (Cd) concentration within edible parts. However, whether Ca and Se can synergistically inhibit Cd accumulation in crops and its mechanism remains poorly understood. A hydroponic experiment was conducted under Cd exposure with the combined supplementation of Ca and Se, specifically focused on Cd accumulation and its mechanism. The results revealed that Ca and Se synergistically enhanced growth and photosynthetic content, whereas they inhibited Cd accumulation in the roots, stems, and leaves of peppers. Ca and Se also synergistically reduced the content of Cd in the cell wall, organelle fraction, and soluble fraction of the roots, as well as in pectin, hemicellulose I, hemicellulose II, and cellulose. Ca and Se supplementation synergistically downregulated the expression levels of CaNramp1, CaNramp5, CaHMA1, and CaHMA2. These results revealed that Ca and Se synergistically reduced Cd accumulation in peppers by modulating targeted gene downregulation involved in Cd absorption and translocation. Full article

Mitochondria are highly dynamic organelles that integrate metabolic regulation, signal transduction, and programmed cell death with their canonical role in adenosine triphosphate (ATP) production. Their ability to undergo continuous remodeling through the opposing processes of fusion and fission is essential for maintaining cellular homeostasis, preserving organelle quality control, and enabling adaptive responses to metabolic and oxidative stress. Among the core regulators of mitochondrial dynamics, the dynamin-related guanosine triphosphatase (GTPase) OPA1 plays a central role in inner membrane fusion, cristae architecture maintenance, bioenergetic efficiency, and the modulation of redox balance and apoptotic signaling. Accumulating evidence indicates that dysregulation of OPA1 expression or activity contributes to the initiation and progression of multiple malignancies, underscoring its importance in tumor cell survival, proliferation, metabolic adaptation, and resistance to stress. Here, we summarize current knowledge on OPA1 dysregulation in cancer and, based on preliminary, unpublished in silico analyses, we highlight the growing relevance of OPA1 as a therapeutic target, particularly through its GTPase domain and the still understudied Interface 7. Overall, these findings outline how integrated computational approaches could potentially guide the identification of novel OPA1 modulators, offering a conceptual framework that highlights OPA1 as a promising, yet still largely underexplored, target in oncology. Full article

Rice blast, caused by the fungal pathogen Magnaporthe oryzae, is one of the most devastating diseases affecting global rice production. Plant essential oils (EOs) have been considered as a promising green alternative to synthetic fungicides. In this study, the antifungal activities of five plant EOs—Acorus calamus, Citrus reticulata, Syzygium aromaticum, Paeonia suffruticosa, and Melaleuca viridiflora—against M. oryzae were evaluated using the mycelial growth rate method. Among them, A. calamus EO (ACEO) exhibited the most pronounced inhibitory effect, with an EC₅₀ value of 0.37 μL/mL. It significantly delayed or inhibited conidial germination and appressorium formation. At higher concentrations (≥1 μL/mL), it also caused morphological abnormalities in appressoria. Observations by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed that the EO treatment caused hyphal surface wrinkling, cell wall thinning, organelle dissolution, and vacuolation. Pathogenicity tests further confirmed that ACEO reduced the virulence of the fungus remarkably, with nearly complete loss of pathogenicity at a concentration of 1 μL/mL. Finally, ACEO was analyzed using gas chromatography-mass spectrometry (GC-MS). The most abundant constituents identified were β-asarone (19.83%) and isoshyobunone (14.92%). Together, these findings demonstrate that ACEO impairs fungal pathogenicity by disrupting hyphal morphology and cellular integrity, highlighting its potential as an effective and eco-friendly fungicide for controlling rice blast. Full article

Pulsed electric fields (PEFs) are widely recognized as a non-thermal, selective physical therapy with wide clinical application in tumor ablation. The pulse width determines how electrical energy is distributed across plasma membrane to intracellular organelles. However, under an engineering-defined equal-dose condition (N·E²·tp), which serves as a practical control parameter rather than a measure of true cellular energy absorption, systematic and comparable experimental characterization of cellular and subcellular responses across pulse widths from the microsecond to nanosecond range remains limited. In this study, PEFs with pulse widths ranging from 100 μs to 50 ns were applied under equal-dose constraints, and cellular responses were evaluated using transmission electron microscopy (TEM), multi-organelle fluorescence imaging, and flow cytometry. The results indicate that pulse-width-dependent effects were observed under a fixed pulse-number, dose-equalized framework in which electric field strength varied across conditions. Structural and functional changes were observed in multiple organelles, including the nucleus, mitochondria, endoplasmic reticulum, and Golgi apparatus. Notably, nanosecond pulses were more effective in inducing mitochondrial membrane potential loss and increasing the proportion of apoptotic or non-viable cells. These findings demonstrate that, under equal-dose conditions, pulse width is a key temporal parameter governing PEF-induced biological effects, indicating that identical dose constraints do not necessarily result in equivalent biological responses. This work provides experimental foundation for parameter selection and optimization in PEF-based biomedical applications. Full article

With intensifying global climate change and human activities, and with regional topography interactions, soil and water salinization has intensified, posing major ecological and environmental challenges worldwide. Here, we integrated histology, transmission electron microscopy, RNA sequencing (RNA-seq) and data-independent acquisition (DIA)-based proteomics to profile hepatopancreas responses of Exopalaemon carinicauda during acute sulfate stress (≤48 h). Sulfate exposure disrupted tubular architecture and organelle integrity, consistent with early cellular injury. Multi-omics analyses revealed metabolic reprogramming marked by suppressed glycolysis (e.g., HK2, ENO) and enhanced oxidative phosphorylation (e.g., ATP5F1B), together with activation of calcium signaling (e.g., SLC8A1, ADCY9) and reinforcement of antioxidant/one-carbon and glucose-branch pathways (e.g., SHMT2, PGAM2). These coordinated transcript–protein changes indicate a shift from rapid cytosolic ATP supply to mitochondrial ATP production while buffering Ca²⁺ overload and reactive oxygen species. Collectively, our results delineate the physiological and molecular adjustments that enable E. carinicauda to cope with sulfate conditions and provide mechanistic targets for selective breeding and water-quality management in saline–alkaline aquaculture. Full article

Oxidative stress, caused by an imbalance between the production of reactive oxygen species and endogenous antioxidant capacity, is a key etiological factor in numerous pathologies, including neurodegenerative and cardiovascular diseases. The limited clinical efficacy of conventional antioxidants is primarily due to their insufficient accumulation within the mitochondria, the main site of intracellular ROS generation. This article reviews the design and application of Mitochondria-Targeted Antioxidants, which represent a major advance in precision medicine. The design of these compounds involves linking an antioxidant “payload” to a lipophilic cation, such as the triphenylphosphonium group. This positive charge leverages the negative electrochemical gradient across the inner mitochondrial membrane to drive the antioxidant into the organelle. This mechanism allows the drug to reach concentrations over 100 times higher than non-targeted alternatives. The discussion encompasses the structure-activity analysis of the carrier, the payload (e.g., quinone derivatives), and the linker, which determine optimal subcellular partitioning and scavenging efficiency. Preclinical data highlight the therapeutic potential of this approach, showing strong neuroprotection in models of Parkinson’s and Alzheimer’s diseases, as well as improved outcomes in cardiovascular and ocular health. By restoring redox balance specifically within the mitochondria, these targeted therapies offer a more effective way to treat chronic oxidative damage. Full article

The endolysosomal system plays a pivotal role in cellular function. Before reaching lysosomes for degradation, the endocytosed cargoes are sorted at various stages of endosomal trafficking for recycling and/or rerouting. The proper execution of these processes depends on tightly regulated ion fluxes across endolysosomal membranes. Recent studies have demonstrated the importance of two-pore channels (TPCs), including TPC1 and TPC2, in endolysosomal trafficking. These channels are expressed in the membranes of distinct populations of endosomes and lysosomes, where they respond to nicotinic acid adenine dinucleotide phosphate (NAADP) and phosphatidylinositol 3,5-bisphosphate [PI(3,5)P₂] to conduct Ca²⁺ and Na⁺ release from these acidic organelles. Here, we discuss the potential implications of Ca²⁺ and Na⁺ fluxes mediated by TPCs across endolysosomal membranes in the physiological and pathophysiological functions of these organellar channels. Full article

PARP inhibitors are a clinically validated class of anticancer therapeutics that exploit synthetic lethality to target homologous recombination-deficient tumors, such as those carrying BRCA1/2 mutations. Nevertheless, the rational design of mitochondria-targeted PARP inhibitors capable of selective mitochondrial accumulation and organelle-specific PARP modulation remains an unresolved objective. To enable organelle-specific modulation of PARP activity, we synthesized a series of trialkyl(aryl)phosphonium conjugates of olaparib and rucaparib designed to target mitochondria by cardiolipin binding. Their activity was evaluated by PARP1 inhibition, cardiolipin affinity, and cytotoxicity in BRCA1-deficient HCC1937 breast cancer cells and non-malignant H9C2 cardiomyocytes. All conjugates retained potent PARP1 inhibition (IC₅₀ = 3.4–17 nM), comparable to the parent drugs. Several derivatives, particularly compounds 2d and 6c, exhibited strong cardiolipin binding (EC₅₀ = 12.99 µM and 6.77 µM, respectively) and significantly enhanced cytotoxicity in HCC1937 cells (IC₅₀ = 0.93 and 2.01 µM), outperforming olaparib and rucaparib. Notably, cytotoxicity toward H9C2 cells was lower, indicating a favorable selectivity profile. Phosphonium conjugation preserves PARP1 inhibitory activity while conferring mitochondrial targeting and enhanced anticancer potency. These findings support the development of mitochondria-targeted PARP inhibitors as a next-generation therapeutic strategy with the potential to improve efficacy and overcome resistance in HR-deficient tumors. Full article

Kidney cells are exposed to a wide range of physiological and pathological stresses, including hormonal changes, mechanical forces, hypoxia, hyperglycemia, and inflammation. These insults can trigger adaptive responses, but when they persist, they can lead to organelle stress. Organelles such as mitochondria, the endoplasmic reticulum, and primary cilia sustain cellular metabolism and tissue homeostasis. When organelle stress occurs, it disrupts cellular processes and organelle communication, leading to metabolic dysfunction, inflammation, fibrosis, and progression of kidney disease. Sex and hormonal factors play a significant role in the development of renal disorders. Many glomerular diseases show distinct differences between the sexes. Chronic Kidney Disease is more common in women, while men often experience a faster decline in kidney function, partly due to the influence of androgens. Additionally, the loss of female hormonal protection after menopause highlights the importance of sex as a factor in renal susceptibility. This narrative review synthesizes preclinical evidence on how sexual dimorphism and sex hormones affect organelle stress in mitochondria, the endoplasmic reticulum, and primary cilia, from 33 studies identified through a non-systematic literature search of the PubMed database, to provide an overview of how these mechanisms contribute to sex-specific differences in kidney disease pathophysiology. Full article

Chloroplasts are key organelles in plants that carry out photosynthesis, convert light energy into chemical energy, and synthesize organic compounds. In this study, a stably heritable chlorophyll-deficient mutant was screened from the ethyl methanesulfonate-induced mutation library of Wuyunjing 21 (WYJ21). This mutant was designated as chlorophyll deficient 6 (cde6). The cde6 mutant exhibits a low chlorophyll content, photosynthetic defects, an impaired chloroplast structure, a significant reduction in the number of stacked thylakoid layers, and a yellow-green leaf phenotype in the early tillering stage. Through MutMap analysis, it was found that the cde6 mutant harbors a single-base mutation (T→A) in the LOC_Os07g38300 gene. This mutation results in an amino acid substitution from valine (Val) to aspartic acid (Asp) in the encoded protein, thereby affecting the protein’s structure and function. The mutation of CDE6 leads to decreased expression of genes related to chloroplast development and chlorophyll biosynthesis. Further studies revealed that the CDE6, a potential chloroplast ribosome recycle factor, leads to high temperature sensitivity in rice when mutated. As high-temperature stress is a primary constraint to global rice productivity, the identification of CDE6 provides a genetic target for improving thermotolerance. In conclusion, these findings demonstrate that CDE6 plays a crucial role in chloroplast biogenesis and provide new insights into its regulatory function in high-temperature tolerance. Full article

The progression of neoplastic diseases is driven by a complex interplay of biological processes, including uncontrolled proliferation, enhanced invasion, metastasis, and profound metabolic reprogramming. Among the hallmarks of cancer, as revised by Hanahan and Weinberg, the reprogramming of energy metabolism has emerged as a critical feature that enables cancer cells to meet their heightened bioenergetic and biosynthetic demands. One significant aspect of this metabolic adaptation is the accumulation of lipid droplets (LDs) dynamic, cytoplasmic organelles primarily involved in lipid storage and metabolic regulation. LDs serve as reservoirs of neutral lipids and play a multifaceted role in cancer cell physiology. Their accumulation is increasingly recognized as a marker of tumor aggressiveness and poor prognosis. By storing lipids, LDs provide a readily accessible source of energy and essential building blocks for membrane synthesis, supporting rapid cell division and growth. Moreover, LDs contribute to cellular homeostasis by modulating oxidative stress, maintaining redox balance, and regulating autophagy, particularly under nutrient-deprived or hypoxic conditions commonly found in the tumor microenvironment. Importantly, LDs have been implicated in the development of resistance to cancer therapies. They protect cancer cells from the cytotoxic effects of chemotherapeutic agents by buffering endoplasmic reticulum (ER) stress, inhibiting apoptosis, and facilitating survival pathways. The presence of LDs has been shown to correlate with increased resistance to a variety of chemotherapeutic drugs, although the precise molecular mechanisms underlying this phenomenon remain incompletely understood. Emerging evidence suggests that chemotherapy itself can induce changes in LD accumulation, further complicating treatment outcomes. Given their central role in cancer metabolism and therapy resistance, LDs represent a promising target for therapeutic intervention. Strategies aimed at disrupting lipid metabolism or inhibiting LD biogenesis have shown potential in sensitizing cancer cells to chemotherapy and overcoming drug resistance. In this review, we comprehensively examine the current understanding of LD biology in cancer, highlight studies that elucidate the link between LDs and drug resistance, and discuss emerging approaches to target lipid metabolic pathways to enhance therapeutic efficacy across diverse cancer types. Full article