Search Results (236)

Objectives: The study aimed to evaluate the effects of full-fat rice bran (FFRB; Tainung No. 81, Taiwan) at various doses on insulin resistance, muscle atrophy, and gut microbiota composition in middle-aged ovariectomized (OVX) mice fed a high-fat diet (HFD), using young sham-operated mice as a life-stage reference group. Methods: Thirty-six female ICR mice were assigned to six groups, including OVX mice fed HFD with or without 5%, 10%, or 20% FFRB. Results: Compared with HFD-fed OVX controls, 20% FFRB reduced body weight gain by 43%, decreased visceral fat mass, and improved insulin resistance (homeostasis model assessment of insulin resistance, HOMA-IR reduced by 65%, P_trend = 0.001). FFRB attenuated the decline in relative grip strength (forelimb, P_trend = 0.013; four-limb, P_trend < 0.001), and upregulated muscle protein synthesis genes, including insulin receptor substrate 1 (IRS-1), mammalian target of rapamycin (mTOR), eukaryotic translation initiation factor 4E binding protein 1 (eIF-4EBP1), while downregulating forkhead box protein O1 (FOXO1), muscle RING-finger protein-1 (MuRF-1), and interleukin (IL)-6. FFRB was also associated with higher fecal acetate levels (P_trend < 0.001), upregulated colonic tight junction genes (occludin and zonula occludens (ZO)-1), and greater relative abundance of g_Muribaculum. Correlation analyses revealed positive associations between short-chain fatty acids (SCFAs) and muscle strength, muscle anabolic markers, genus Lachnospiraceae_UCG_001, and Muribaculum. Conclusions: Dietary inclusion of FFRB was associated with favorable metabolic and muscle-related parameters in HFD-fed middle-aged OVX mice, with potential involvement of gut microbiota and SCFA alterations. Full article

Plants perceive light signals through photoreceptors such as CRY1 to regulate growth and development. It is well-known that Arabidopsis CRY1 is a nucleocytoplasmic protein that mediates light inhibition of hypocotyl elongation in the nucleus, but the mechanisms by which CRY1 regulates root growth and functions in the cytoplasm remain poorly understood. Here, we identified eIF3G1, a subunit of the eukaryotic translation initiation factor 3 (eIF3) complex, as a CRY1-interacting protein associated with light-regulated root development. Under blue light, eif3g1 mutants showed longer primary roots, whereas eIF3G1 overexpression reduced root elongation, accompanied by corresponding changes in root apical meristem size. Differential irradiation experiments indicated that shoot illumination is required for eIF3G1-dependent root phenotypes. Transcriptome analysis revealed changes in translation-related and light-responsive genes in response to eIF3G1 perturbation. Comparison with the cry1 transcriptome revealed overlapping differentially expressed genes, including BIC1 and BIC2, and the bic1 bic2 double mutant showed reduced root elongation. Together, these findings identify eIF3G1 as a CRY1-interacting factor that contributes to the shoot-dependent regulation of root growth under blue light, suggesting that eIF3G1 may be associated with the CRY1-dependent shoot-to-root regulation of root growth. Full article

Programmed cell death 4 (PDCD4) protein is a tumour suppressor protein that inhibits mRNA translation by inhibiting RNA helicase, eukaryotic initiation factor 4A (eIF4A). We have previously reported that PDCD4 interacts with the internal ribosome entry site (IRES) element of B-cell lymphoma extra-large (Bcl-xL) mRNA and inhibits its IRES-mediated translation initiation. S6 kinase (S6K)-mediated phosphorylation of PDCD4 activates its degradation and derepresses IRES-mediated translation initiation of Bcl-xL mRNA. eIF3F (one of the subunits of eIF3 complex) was reported to recruit S6K to phosphorylate eIF3G. Therefore, we investigated the possibility of co-regulation of PDCD4 and eIF3F by S6K and the regulation of IRES-mediated translation initiation by PDCD4–eIF3F. Here, we demonstrated that PDCD4 interacts with several subunits of eIF3. Specifically, eIF3F directly interacts with PDCD4 in an RNA-independent manner. Depletion of PDCD4 in glioblastoma (GBM) cells resulted in decreased levels of certain eIF3 subunits, including eIF3F. Additionally, depletion of eIF3F from GBM cells decreased the levels of PDCD4 protein. We also showed that PDCD4 and eIF3F directly interact with Bcl-xL RNA independently of each other. By performing IRES reporter, polysome profiling assays and EMSA we have demonstrated that eIF3F regulates IRES-mediated translation of Bcl-xL mRNA, likely via its interaction with PDCD4. Full article

Euonymus bungeanus is a highly valued ornamental tree/shrub species widely utilized in landscaping and afforestation in Northeast Asia, yet molecular studies on this species remain limited due to the lack of validated reference genes for reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR). In this study, 16 candidate reference genes were selected based on classical plant reference genes and our previous transcriptome data. Their expression stability was comprehensively evaluated using 64 samples collected from diverse tissues and plants subjected to various abiotic stress/hormone treatments across multiple time points. Across all samples analyzed, PBG1 (20S proteasome beta subunit G1) exhibited the highest overall expression stability, followed by VAPD (vacuolar ATP synthase subunit D) and EIF4A (eukaryotic translation initiation factor 4A). For tissue-specific analysis, TSR2 (pre-rRNA-processing protein), VAPD, and PBG1 demonstrated the greatest stability. Under specific stress conditions, PBG1 and EIF4A were identified as the most stable genes under low- and high-temperature conditions. PP2A (protein phosphatase 2A) and TUB6 (beta-6 tubulin) were optimal for drought stress, while TSR2, SRP (nuclear speckle splicing regulatory-like protein), and PBG1 exhibited superior stability under salt stress. These findings establish a validated panel of reference genes enabling accurate and reliable gene expression normalization in E. bungeanus, thereby facilitating future functional genomics studies in this economically and ecologically important species. Full article

Background: Endocrine therapy with tamoxifen remains a cornerstone in the treatment of estrogen receptor-positive (ER+) breast cancer; however, the emergence of resistance to its active metabolites, 4-hydroxytamoxifen (4-OHTAM) and Endoxifen, represents a major clinical limitation. Increasing evidence suggests that drug efflux transporters, redox-adaptive signaling, and translational control mechanisms may converge to promote chemoresistance. This study aimed to investigate the coordinated expression patterns of ABCC transporters, the eukaryotic initiation factor 4F (eIF4F) complex, and NRF2 signaling in tamoxifen-metabolite-resistant MCF-7 breast cancer cells. Methods: MCF-7 cell variants resistant to 4-OHTAM (Variant B) or Endoxifen (Variant C) were established through prolonged drug exposure. Cytotoxicity assays assessed cellular viability and chemoresistance. Protein expression and molecular interactions were analyzed using Western blotting and co-immunoprecipitation. Flow cytometry was employed to evaluate transporter-associated fluorescence intensity. In silico molecular docking was performed to estimate the binding affinity of tamoxifen metabolites to ABCC transporters. Results: Endoxifen-resistant cells exhibited the most pronounced chemoresistant phenotype. Analysis of ABCC transporters revealed modest but consistent increases in fluorescence intensity across resistant variants; however, these differences did not reach statistical significance. Dysregulation of the eIF4F complex was observed, with increased eIF4E and reduced eIF4A levels, suggesting altered translational control associated with resistant phenotypes. Increased NRF2 protein expression was detected in resistant variants, consistent with enhanced redox-adaptive capacity. Analysis of ABCC transporters revealed modest but consistent increases in fluorescence intensity across resistant variants; however, these differences did not reach statistical significance. Molecular docking demonstrated strong binding affinity between Endoxifen and ABCC2, supporting a potential role for transporter-mediated efflux. Conclusions: Tamoxifen-metabolite resistance in ER+ breast cancer is associated with coordinated trends in ABCC transporter-associated signals, altered eIF4F complex expression, and sustained NRF2 signaling. These findings suggest the presence of a multifactorial adaptive network that may contribute to endocrine resistance. Targeting components of this network warrants further mechanistic investigation. Full article

The polyamine metabolic pathway, an evolutionarily conserved nexus integrating nutrient sensing, translation control, and cellular proliferation, is fundamentally rewired in cancer. Melanoma, a malignancy of melanocytes notorious for its metastatic propensity and therapy resistance, exhibits a profound dependency on this pathway, extending beyond mere polyamine abundance to the specialized function of their derivative, hypusine. This review synthesizes cutting-edge insights into the deoxyhypusine synthase (DHPS)/eukaryotic initiation factor 5A (eIF5A) hypusination circuit as a critical amplifier of oncogenic signaling in melanoma. We dissect its role as a translational rheostat for pro-tumorigenic proteomes, a driver of phenotypic plasticity underpinning invasion and vasculogenic mimicry, and a modulator of the immunosuppressive tumor microenvironment. Moving beyond the classical inhibitor GC7, we explore the emergence of novel allosteric DHPS inhibitors with compelling preclinical efficacy. Finally, we propose a paradigm shift: targeting the DHPS/eIF5A axis represents a strategy to disrupt the “non-oncogene addiction” of melanoma—its reliance on hyperactive translation and adaptive survival mechanisms—offering a promising avenue alongside targeted therapies and immunotherapies. Full article

The eukaryotic translation initiation factor 4E (eIF4E) family plays a dual role in plants, regulating cap-dependent protein synthesis and mediating susceptibility to viruses in the family Potyviridae. In cowpea (Vigna unguiculata (L.) Walp.), an economically important legume cultivated worldwide, the structural determinants of these isoforms remain largely unexplored. This study characterizes the genomic organization, evolutionary history, and conformational dynamics of eIF4E, eIF(iso)4E, and nCBP in cowpea using a multi-omics approach. Genome mining identified three paralogous genes located on chromosomes 4, 6, and 7, showing high synteny with Phaseolus vulgaris. Phylogenetic analysis confirmed nCBP as the ancestral Class I lineage, distinct from the Class II eIF4E and eIF(iso)4E clades. Theoretical models for the isoforms were generated and subsequently validated by molecular dynamics simulations, revealing that while all isoforms preserve the canonical tertiary architecture and an electropositive cap-binding pocket, eIF(iso)4E exhibits superior structural compactness and hydrogen-bond stability. These biophysical features highlight their role as a stable anchor for viral VPg proteins. By elucidating the atomic-level landscape of these factors, we provide a robust structural framework to guide allele mining and genome-editing strategies aiming to engineer virus-resistant cowpea cultivars without compromising agronomic performance. Full article

Foot-and-mouth disease virus (FMDV) is a highly contagious picornavirus that affects cloven-hoofed animals and carries significant economic implications for the global livestock industry. FMDV features two Leader (L) protein isoforms, Lab and Lb, differing at their amino termini by 28 amino acids (La region). Currently, the activity of La protein sequences has not been investigated. To address this issue, the comparison study of biological and functional roles of Lab and Lb was performed as the La region alone did not independently perform protein function. We found that Lab and Lb significantly regulated FMDV replication and pathogenicity, and their coexistence afforded optimal FMDV properties. Subsequently, we observed that both L isoforms cleaved eukaryotic translation initiation factor 4G (eIF4G) I, suppressed type I and type III interferon (IFN) expression, and exhibited marked cytotoxicity, indicating that they were all key components in FMDV’s antagonism of host antiviral defenses. Finally, the subcellular distribution of Lab and Lb was detected. Despite dual localization in cytoplasmic and nuclear compartments, both isoforms displayed different spatial distribution patterns, and Lb induced more pronounced morphological changes to host cells than Lab. Furthermore, bioinformatics predicted that the La region might contain a non-classical secretory signal peptide, potentially facilitating Lab distribution to the cell membrane or extracellular space. Collectively, the primary encoding role of La region was to control the intracellular distribution of L protein, as opposed to regulating its functional activity. This study may help to deepen our understanding of why FMDV encoded two isoforms of L protein. Full article

Hypomyelinating leukodystrophies (HLDs) are a group of hereditary CNS disorders characterized by hypomyelination and, sometimes, repeated cycles of demyelination and remyelination. In HLDs, various genetic mutations in the responsible genes disrupt the morphogenesis of oligodendrocytes (oligodendroglial cells), which wrap neuronal axons with their differentiated myelin sheaths. A stop-loss mutation (c.622T-C or c.622T-G) in the gene encoding claudin family tetraspan plasma membrane protein claudin-11 (CLDN11) is associated with HLD22, which is characterized by incomplete differentiation and hypomyelination or delayed myelination in the brain. Herein, we describe for the first time that a CLDN11 mutant protein with an additional amino acid sequence due to the stop-loss mutation, but not the wild-type protein, leads to decreased expression of oligodendroglial differentiation marker proteins in the FBD-102b oligodendroglial progenitor cell line, the model undergoing its differentiation, at both the molecular and morphological levels. Consistently, mutant CLDN11 exhibited decreased morphological differentiation with a reduced ability to extend processes. These cells contained punctate structures that were partially localized in the endoplasmic reticulum (ER) and stimulated phosphorylation of c-Jun N-terminal kinase (JNK) and eukaryotic translation initiation factor 2A (eIF2A) kinase, ER stress-responsible kinases. Hesperetin, a neuroprotective flavonoid that can downregulate ER stress, recovered the differentiation abilities of these cells. Notably, the effects were related to decreased phosphorylation of ER stress-responsible kinases. JNK was found to be present in a co-precipitate with the hesperetin core, whereby hesperetin inhibited signaling through c-Jun as a negative regulator of differentiation. These findings indicate that the HLD22-associated mutant protein can cause an ER stress response, decreasing cell morphological differentiation. In addition, this study offers possible therapeutic implications for the as-yet-unexplored mechanisms involved in HLD22, at least at the molecular and cellular levels. Full article

Eukaryotic initiation factor 2 (EIF2) signaling plays a crucial role in regulating mRNA translation and initiating eukaryotic protein synthesis. Computational molecular network pathway analysis of the canonical pathways of the coronaviral infection revealed that EIF2 signaling is inactivated when the coronavirus pathogenesis pathway is activated and vice versa. Our computational analyses indicated that the coronavirus pathogenesis pathway and EIF2 signaling had inverse activation states. Computational investigation of upstream or downstream microRNA (miRNA) revealed that EIF2 signaling directly interacted with miRNAs, including let-7, miR-1292-3p (miRNAs with the seed CGCGCCC), miR-15, miR-34, miR-378, miR-493, miR-497, miR-7, miR-8, and MIRLET7. A total of 36 nodes, including 8 molecules (ATF4, BCL2, CCND1, DDIT3, EIF2A, EIF2AK3, EIF4E, and ERK1/2), 1 complex (the ribosomal 40s subunit), and 1 function (apoptosis) in the coronavirus pathogenesis pathway, overlapped with EIF2 signaling. Alterations in EIF2 signaling may play a role in the pathogenesis of coronavirus. Full article

Radiation-induced brain injury (RBI) is a severe complication of cranial radiotherapy that poses a significant clinical challenge due to a lack of effective treatments. Ferroptosis, an oxidative stress-driven cell death pathway, has been implicated in its pathogenesis. Here, we report that 75% ethanol (GBF-8), a novel subfraction isolated from male Ginkgo biloba flowers, confers significant protection against RBI. In a murine RBI model, GBF-8 administration restored cognitive function and alleviated neuroinflammation. We demonstrated that this neuroprotective effect is mechanistically linked to ferroptosis inhibition. Integrated proteomic and metabolomic profiling identified the Solute carrier family 7 member 11 (Slc7a11)–Eukaryotic Translation Initiation Factor 4E Binding Protein 1 (Eif4ebp1) axis as the primary target of GBF-8. This work not only establishes GBF-8 as a promising therapeutic candidate but also delineates a previously unrecognized regulatory axis for combating ferroptosis in RBI. Full article

The presence of aberrant double-stranded DNA (dsDNA) in the cytoplasm of cells is sensed by unique pattern recognition receptors (PRRs) to trigger innate immune response. The cyclic GMP–AMP synthase (cGAS)–stimulator of interferon genes (STING) signaling pathway is activated by the presence of non-self or mislocalized self-dsDNA from nucleus or mitochondria released in response to DNA damage or cellular stress in the cytoplasm. Activation of cGAS leads to the synthesis of the second messenger cyclic GMP–AMP (cGAMP), which binds and activates STING, triggering downstream signaling cascades that result in the production of type I interferons (IFNs) and proinflammatory cytokines. Here, we show that diverse immunostimulatory dsDNA ligands and chemotherapy agents like Doxorubicin and Taxol trigger the integrated stress response (ISR) by activating endoplasmic reticulum (ER) stress kinase, protein kinase RNA-like ER kinase (PERK), in addition to the canonical IFN pathways. PERK-mediated phosphorylation and inactivation of the alpha subunit of eukaryotic translation initiation factor-2 (eIF2α) result in the formation of stress granules (SGs). SG formation by dsDNA was significantly reduced in PERK knockout cells or by inhibiting PERK activity. Transcriptional induction of IFNβ and cytokines, ISR signaling, and SG formation by dsDNA was dampened in cells lacking PERK activity, STING, or key stress-granule nucleating protein, Ras-GAP SH3 domain-binding protein 1 (G3BP1), demonstrating an important role of the signal transduction pathway mediated by STING and SG assembly. Lastly, STING regulates reactive oxygen species (ROS) production in response to DNA damage, highlighting the crosstalk between DNA sensing and oxidative stress pathways. Together, our data identify STING–PERK–G3BP1 signaling axis that couples cytosolic DNA sensing to stress response pathways in maintaining cellular homeostasis. Full article

Immunogenic cell death (ICD) is a subtype of regulated cell death characterized by the spatiotemporally coordinated emission of damage-associated molecular patterns (DAMPs), such as calreticulin (CALR), ATP, and high-mobility group box-1 (HMGB1), which collectively prime tumor-specific T-cell responses. Autophagy, a lysosome-dependent catabolic process, is increasingly recognized as a key modifier of antitumor immunity and the tumor microenvironment (TME). In preclinical models, autophagy can not only promote ICD by sustaining endoplasmic reticulum (ER) stress, eukaryotic translation initiation factor-2α (eIF2α) phosphorylation, and secretory pathways, but it can also limit ICD by degrading DAMPs, antigenic cargo, and major histocompatibility complex (MHC) molecules. The net outcome is highly context-dependent and determined by the tumor type, the nature and intensity of the stress, and the level at which autophagy is modulated. Herein, we summarize how autophagy affects the three canonical ICD-associated DAMPs, highlight solid-tumor models in which autophagy supports ICD, and contrast them with systems wherein autophagy inhibition is required for immunogenicity. We then focus on hematological malignancies, especially multiple myeloma, where recent reports implicate the autophagy-related protein GABARAP in bortezomib-induced ICD. Finally, we discuss the translational implications, including rational combinations of autophagy modulators with ICD-inducing chemotherapies, targeted drugs, and cellular immunotherapies, and outline the remaining challenges for safely harnessing the autophagy–ICD axis in the clinical setting. Full article

Background/Objectives: The selection and validation of species-specific housekeeping genes (HKGs) have become increasingly common in functional genomics, with application of quantitative Polymerase Chain Reaction (qPCR) or cDNA-based qPCR (RT-qPCR). Despite the Macrobrachium amazonicum having RNA-seq studies available, there are still no data on the most stable and consistent HKGs for use in relative gene expression analyses. Therefore, the present study aimed to identify and validate seven HKGs in M. amazonicum: Eukaryotic Translation Initiation Factor (EIF), 18S ribosomal RNA (18S), Ribosomal Protein L18 (RPL18), β-actin, α-tubulin (α-tub), Elongation Factor 1-α (EF-1α), and Glyceraldehyde-3-phosphate Dehydrogenase (GAPDH). Methods: The HKGs were identified in the M. amazonicum transcriptome, characterized for identity confirmation, and compared against public databases. Subsequently, RT-qPCR assays were prepared using muscle, hepatopancreas, gills, testis, androgenic gland, and ovary to assess the stability of the HKG markers, employing the comparative ∆Ct, BestKeeper, NormFinder, and GeNorm methods. Results: All candidate HKGs identified showed high similarity with other decapods. Reactions performed with these markers demonstrated high specificity, PCR efficiency, and elevated coefficients of determination. The comprehensive ranking, indicated that no single HKG was stable across all tissues, with HKGs showing the best stability being tissue-specific. The most stable HKGs were RPL18 and 18S. GAPDH, historically used as an HKG, showed the poorest performance in stability ranking for most tissues tested, whereas β-actin was most suitable only for ovarian. Conclusions: These data reinforce the need for species-specific HKG validation and provide an appropriate panel of reference markers for gene expression studies in the M. amazonicum. Full article

The localization and remodeling of mRNPs is inextricably linked to translational control. In recent years there has been great progress in the field of mRNA translational control due to the characterization of the proteins and small RNAs that compose mRNPs. But our initial assumptions about the physical nature and participation of germ cell granules/condensates in mRNA regulation may have been misguided. These “granules” were found to be non-membrane-bound liquid–liquid phase-separated (LLPS) condensates that form around proteins with intrinsically disordered regions (IDRs) and RNA. Their macrostructures are dynamic as germ cells differentiate into gametes and subsequently join to form embryos. In addition, they segregate translation-repressing RNA-binding proteins (RBPs), selected eIF4 initiation factors, Vasa/GLH-1 and other helicases, several Argonautes and their associated small RNAs, and frequently components of P bodies and stress granules (SGs). Condensate movement, separation, fusion, and dissolution were long conjectured to mediate the translational control of mRNAs residing in contained mRNPs. New high-resolution microscopy and tagging techniques identified order in their organization, showing the segregation of similar mRNAs and the stratification of proteins into distinct mRNPs. Functional transitions from repression to activation seem to corelate with the overt granule dynamics. Yet increasing evidence suggests that the resident mRNPs, and not the macroscopic condensates, exert the bulk of the regulation. Full article