Search Results (273)

The plague, caused by Yersinia pestis, has resulted in significant mortality over the past century. Despite advances in antimicrobial therapy, plague remains a re-emerging infectious disease with ongoing outbreaks and increasing concerns regarding antimicrobial resistance. Today, plague cases are still being reported, and the loss of effectiveness of treatment methods remains a major challenge. Therefore, effective treatment strategies are needed. In this study, we aimed to develop aptamers specific to Yersinia outer protein M (YopM), a key immunosuppressive protein that is essential for virulence. Our goal was to develop an aptamer that binds to YopM and inhibits its interaction with the human DEAD-box helicase 3 (DDX3) protein. YopM-DDX3 protein interaction was targeted because of its key role in nucleocytoplasmic shuttling of YopM. To achieve this, we developed the YopM16 aptamer using magnetic bead-based (Systematic Evolution of Ligands by Exponential Enrichment) (SELEX). The selected YopM16 aptamer exhibited a half-maximal inhibitory concentration(IC₅₀) value of 103.3 ± 2 nM and effectively inhibited the interaction between YopM and DDX3. The inhibitory effect of the aptamer on protein interaction was confirmed using a pull-down assay and colorimetric test. Given that protein–protein interaction surfaces are considered undruggable, YopM16 is a promising inhibitor with the potential to serve as a molecular tool to investigate the virulence mechanism of YopM, as well as a novel antibacterial agent upon validation of its inhibition in cellular models. Full article

Boule is the ancestral member of the Deleted in Azoospermia (DAZ) family and is pivotal for gametogenesis and male fertility in most animals. However, there is a dearth of information on molluscan boule. Here, we identified a counterpart (Pcbol) from the genome of Pomacea canaliculata, which has emerged as a cosmopolitan alien species and notorious pest that causes devastating damage to aquatic biodiversity, freshwater ecosystems and crop production in invaded ranges. This study aimed to investigate the biological roles of Pcbol in male reproduction and to decipher the molecular mechanisms underpinning its modulation via dsRNA-delivered RNA interference (RNAi). The bioinformatic analysis showed that the Pcbol genomic sequence is 12,934 nt in length, harboring an open reading frame of 294 nt that encodes 97 aa residues, with an RRM domain evolutionarily conserved among molluscan orthologues. Spatiotemporal expression profiling indicated the predominant abundance of Pcbol in adult males and testis tissues. dsPcbol, injected at a dose of 4 μg/per snail for 5 days, yielded optimal silencing at both transcript and translation levels of Pcbol, as revealed by qRT-PCR and Western blotting. Immunofluorescence echoed a pronounced reduction in Pcbol signal intensity following RNAi. In addition to the arrested reproductive gland phenotype, the number of sperm cells substantially dwindled upon dsPcbol treatment relative to the dsGFP control. In biochemical and fecundity assays, Pcbol depletion triggered a significant decrease in Te/SP/Arg content and suppressed the number of deposited eggs and hatchability. Furthermore, spermatogenic genes like CDC25/TSSK1/SPATA17/DDX4/Dmrt2/Sox2/Kelch10/SPO11 displayed considerable downregulation post Pcbol silencing, with molecular docking predicting a strong affinity between CDC25 and Pcbol. These molecular modules may interact with Pcbol to mediate knockdown effects on spermatogenesis dysfunction. Collectively, our findings not only confirmed that boule was indispensable for spermatogenesis and male fertility in a mollusk, but also highlighted the Pcbol-based male sterile technique (MST), which can be incorporated into precision pest management (PPM) strategies for sustainable control of P. canaliculata. Full article

Diapause is a vital overwintering strategy for many insects, yet its comprehensive molecular architecture remains elusive. In the polyphagous pest Helicoverpa armigera, facultative pupal diapause is key to its ecological success. To elucidate the complex diapause regulatory network, we conducted a transcriptomic analysis of diapause (DP) versus non-diapause (NP) pupal brains across early pupal development (days 2, 5, and 10). Integrated analyses, including differential expression, persistent gene identification, weighted gene co-expression network analysis (WGCNA), and multiscale embedded network analysis (MEGENA), were employed to define core regulatory modules and hubs. The number of differentially expressed genes (DEGs) increased over time, with 1781 genes persistently regulated across all time points, enriched in mitochondrial metabolism, hormone signaling, and chromatin remodeling. WGCNA revealed a diapause-associated module (red) linked to RNA processing/transcription and a development-associated module (blue) enriched for translation and mitochondrial metabolism. Network analyses pinpointed three central hub genes: DDX5 and PLK4 (downregulated in diapause, upregulated upon 20E treatment) and TAF5L (upregulated in diapause, downregulated after 20E). This study provides a systems-level view of the transcriptional landscape governing pupal diapause in H. armigera and identifies novel candidate regulators for future functional studies. Full article

Ducks, once considered mere reservoirs, now serve as both victims and amplifiers of persistent highly pathogenic avian influenza (HPAI) virus cycles in wild populations. The molecular pathogenesis of HPAI is shaped by complex, dysregulated molecular networks, necessitating a systems biology approach that integrates computational modeling of host–pathogen interactions. Despite recent advances, a comprehensive understanding of the signaling pathways, molecular mechanisms, and hub genes driving HPAI H5N1 pathogenesis in avian hosts remains incomplete. This study addresses this gap by employing an integrated multi-omics strategy—combining transcriptomic, proteomic, and phosphoproteomic analyses—to map the signaling networks and key host factors involved in HPAI H5N1 infection in duck lung tissue. Our network analysis revealed activation of RIG-I-like receptor, toll-like receptor, NOD-like receptor, NF-κB, and JAK/STAT signaling pathways. Phosphoproteomic profiling independently confirmed the activation of these pathways, supporting the integrated network findings. Key regulatory hub genes identified include STAT1, DDX58 (RIG-I), MYD88, NFKBIA, NFKB1, IRF7, SOCS3, ACTB, TLR4, TLR7, IL-6, CASP1, and CASP8, which form a central hub in duck antiviral immunity. Some of these genes may represent promising targets for therapeutic or vaccine development against avian influenza. Collectively, this work delineates the critical signaling pathways and hub genes underlying HPAI H5N1 pathogenesis in ducks through comprehensive multi-omics integration. Full article

Small cell lung cancer (SCLC) is an aggressive malignancy characterized by rapid progression, early metastasis, and high relapse rates due to acquired chemoresistance. The human DEAD-box RNA helicase DDX5 is overexpressed in SCLC and has recently gained attention as a viable therapeutic target. Supinoxin (RX-5902), a selective small-molecule inhibitor of DDX5, exhibits strong anti-tumor activity. Recent evidence suggests that its cytotoxic effects are mediated through the disruption of mitochondrial respiration. In this study, transcriptomic profiling via RNA sequencing (RNA-seq) revealed significant downregulation of genes involved in cellular respiration following Supinoxin treatment and DDX5 knockdown in chemoresistant H69AR cells. To functionally validate these findings, we employed the Seahorse XF Cell Mito Stress Test, which measures key parameters of mitochondrial bioenergetics through oxygen consumption rate (OCR) analysis. Supinoxin-treated cells exhibited marked mitochondrial dysfunction, supporting the hypothesis that DDX5 inhibition disrupts cellular energy metabolism. These findings illuminate a previously underappreciated role of DDX5 in mitochondrial regulation and offer mechanistic insights into Supinoxin’s cytotoxic effects, underscoring its potential as a targeted therapy in SCLC. Full article

The differentiation of human embryonic stem cells (hESCs) into primordial germ cell-like cells (PGC-LCs) provides a robust in vitro model to study human germline specification. Here, we present a simple, reproducible, and cost-effective protocol for generating DEAD-box helicase 4 (DDX4)/VASA and Deleted in Azoospermia-Like (DAZL)-positive PGC-LCs from hESCs using a combination of bone morphogenetic protein 4 (BMP4) and conditioned medium (CM) derived from Stage-Specific Embryonic Antigen-4 (SSEA4)-positive human amniotic fluid stem cells (hAFSC-4). Importantly, unlike conventional protocols that rely on embryoid body formation, our method employs adherent cultures for germ cell differentiation. This approach enhances reproducibility by avoiding the spontaneous and stochastic variability inherent to embryoid body formation. This protocol provides a reproducible and physiologically relevant platform for studying human germ cell development in vitro. Full article

Fibrosis appears to be an out-of-control wound-healing response that drives a progressive formation of scar tissue in an organ. A key profibrotic cytokine, transforming growth factor beta-1 (TGF-β1), upregulates levels of the extracellular sialidase neuraminidase 3 (NEU3), and NEU3 in turn can activate latent TGF-β1 to release active TGF-β1 from the sequestering latency-associated peptide (LAP). In the mouse bleomycin model of pulmonary fibrosis, NEU3 is both necessary and sufficient for pulmonary fibrosis. In this report, we find that NEU3 protein levels increase both intracellularly and extracellularly in cultures of human lung fibroblasts within 5 min of TGF-β1 exposure. This effect is driven by an increase in translation and is independent of new transcription, supporting a model where TGF-β1 causes a pool of weakly translated NEU3 mRNA to increase translation. By participating in the feedback loop, latent TGF-β1 makes cells more sensitive to TGF-β1. LAP also stimulates NEU3 expression and acts synergistically with TGF-β1 to upregulate NEU3. The positive feedback loop is blocked by NEU3 inhibitors. The RNA helicase DEAD-box helicase 3 (DDX3) mediates NEU3 translation, and the DDX3 inhibitor RK-33 blocks the rapid upregulation of NEU3 by TGF-β1 and LAP. Exposure of cells to TGF-β1 but not LAP induces dephosphorylation of DDX3 within two minutes, suggesting that the mechanisms used by TGF-β1 and LAP to activate DDX3 to increase NEU3 levels may differ. Together, these results suggest that a rapid positive feedback loop involving TGF-β1, LAP, and NEU3 helps drive fibrosis. Full article

Locusta migratoria (Orthoptera: Acrididae) is a major agricultural pest, characterized by its strong reproductive capacity and rapid reproduction rate. Consequently, identifying novel targets to control or reduce the fecundity of locusts is of significant practical importance. Insulin/insulin-like growth factor signaling (IIS) and the DEAD-box RNA helicase 3 (DDX3) exhibit extensive functional convergence; both govern key life-history traits in insects, including lifespan, metabolic homeostasis, and fecundity. Strikingly, each pathway can influence oogenesis through Notch signaling. Thus, we hypothesize that DDX3 may modulate insect reproduction associated with this pathway. After silencing DDX3 through RNA interference (RNAi), we found that the key genes of IIS were significantly downregulated and the content of trehalose and glycogen decreased significantly, proving that DDX3 inhibits reproduction associated with IIS. In addition, DDX3 interference led to a marked reduction in the mRNA expression of Vgs (VgA/B) and JHAMT, which was accompanied by a significant decrease in ovarian development. Furthermore, integrating our previous findings, we posit that DDX3 engages in locust reproduction via the regulation of pivotal IIS pathway genes such as InR and FOXO, thereby completing the putative regulatory circuitry through which DDX3 modulates reproductive processes. Our findings deepen the understanding of the endogenous circuitry governing locust reproduction and provide novel theoretical justification for targeting DDX3 in locust management strategies. Full article

Background: Multiple myeloma (MM) is a hematologic malignancy characterized by clonal plasma cell expansion and diverse genomic rearrangements, including immunoglobulin heavy chain (IGH) translocations. Although RNA sequencing enables the comprehensive detection of IGH-associated fusions, routine molecular monitoring remains limited, particularly in non-secretory MM (NSMM), which lacks measurable serologic markers. Methods: Here, we contracted an integrated system combining RNA sequencing (RNA-seq) and reverse transcription quantitative polymerase chain reaction (RT-qPCR) to identify and validate fusion gene-based molecular markers for minimal residual disease (MRD) monitoring. Results: The global fusion landscape was delineated by the sequencing analysis of bone marrow samples from 22 newly diagnosed patients with MM. A total of 362 fusion events were identified, of which 190 non-immunoglobulin fusions were selected for detailed characterization. Recurrent breakpoints were concentrated on chromosomes 1 and 19, and five recurrent fusions, DDX5::EEF1A1, OAZ1::KLF2, OAZ1::KLF16, PFKFB3::LINC02649, and PLXNB2::SCO2, were detected across nine patients. Functional enrichment analyses indicated the significant involvement of these genes in RNA splicing regulation, transcriptional misregulation in cancer-related pathways, and focal adhesion processes. Twenty-three fusion transcripts were validated using RT-PCR and Sanger sequencing, demonstrating high specificity for MM. Longitudinal monitoring revealed that the quantitative assessment of fusion transcript levels enabled earlier relapse detection than flow cytometry, including in NSMM, where conventional MRD tools are ineffective. Conclusions: These findings suggest that individualized fusion transcripts serve as robust molecular markers for MRD surveillance. The proposed RNA-seq–RT-qPCR pipeline offers a clinically practical strategy to enhance precision diagnosis and personalized treatment in MM. Full article

Background: Prenatal detection of fetal structural anomalies often prompts chromosomal analysis; however, chromosomal microarray analysis (CMA) has limited diagnostic yield for monogenic disorders. Whole-exome sequencing (WES) has emerged as a powerful tool for identifying single-gene etiologies, particularly in cases with complex neurodevelopmental phenotypes. Case Presentation: We report a female infant presenting with prenatally detected ventriculomegaly and inconclusive chromosomal testing. Prenatal investigations, including karyotyping and genome-wide chromosomal sequencing, identified several copy number variants classified as variants of uncertain significance but failed to establish a definitive diagnosis. Postnatally, the patient developed progressive neurological abnormalities, including microcephaly, facial dysmorphism, dystonic movements, and severe global developmental delay. Trio-based whole-exome sequencing identified a heterozygous de novo pathogenic missense variant in the DDX3X gene (c.976C>T; p.Arg326Cys), establishing the diagnosis of DDX3X-related neurodevelopmental disorder. Conclusions: This case highlights the diagnostic limitations of standard prenatal chromosomal testing in detecting monogenic neurodevelopmental disorders and underscores the critical role of timely genetic counseling and exome sequencing. Earlier selective implementation of WES during pregnancy could have enabled an earlier diagnosis, improved prognostic counseling, and optimized clinical decision-making. Full article

DEAD-box (DDX) RNA helicases are essential regulators of RNA metabolism and gene expression. Among them, DDX10 remains poorly characterized despite growing evidence supporting its involvement in human diseases. This review provides a comprehensive analysis of DDX10, from its structural and functional features to its emerging roles in solid tumors and hematologic malignancies. We discuss how DDX10, through its conserved domains, contributes to pre-rRNA processing, ribosome biogenesis, and cell proliferation, and explore potential links between DDX10 and processes such as liquid–liquid phase separation (LLPS) and epigenetic regulation, which may underlie its roles in cancer cell plasticity and stress response. We argue that the dysregulation of these fundamental cellular processes positions DDX10 as a focal point where aberrant RNA metabolism and altered molecular condensates converge to disrupt transcriptional homeostasis and drive oncogenic transformation. Aberrant DDX10 expression is a recurrent feature across multiple cancers, where it promotes tumor progression, therapy resistance, and poor prognosis. Moreover, DDX10 participates in oncogenic fusion events, most notably the NUP98::DDX10 fusion identified in a subset of acute myeloid leukemias, which drives leukemogenesis by disrupting transcriptional regulation and cellular differentiation. Given its tumor-associated expression and diverse biological functions, DDX10 is increasingly recognized as a potential diagnostic biomarker and a promising target for therapeutic strategies. By consolidating current knowledge under this unifying framework, this review highlights the multifaceted roles of DDX10 in cancer biology, advocating further research into its molecular functions and translational potential. Full article

The World Health Organization (WHO) and International Consensus Classification (ICC) systems have classified EBV-positive NK/T-cell neoplasms in adults and EBV-positive T/NK-cell lymphoid lymphoproliferative disorders (LPD) in children. Recent molecular profiling techniques have revealed the pathogenesis of these disorders, showing interactions among EBV-encoded proteins, host immune responses, and genetic alterations. Extranodal NK/T-cell lymphoma (ENKTL) shows molecular diversity, with various subtypes (TSIM, MB, and HEA) identified through a multiomics approach. Aggressive NK-cell leukemia (ANKL) has mutations in JAK/STAT, epigenetic regulators, and TP53 pathways. EBV-positive nodal T- and NK-cell lymphoma (ENTNKL) is a new entity, distinguished by primary nodal presentation and a unique molecular profile. Severe mosquito bite allergy (SMBA), hydroa vacciniforme lymphoproliferative disorder (HVLPD), and systemic chronic active EBV disease (CAEBV) are rare childhood EBV-driven LPDs defined by clinico-pathologic criteria, with largely unexplored genomic landscapes. Studies of CAEBV samples have found ENKTL-like driver mutations, including DDX3X and KMT2D, in EBV-infected NK/T cells, while KMT2D and chromatin modifier mutations were common in HVLPD. Comprehensive molecular sequencing of SMBA and Systemic EBV-positive T-cell lymphoma of childhood remains lacking. These findings suggest all EBV⁺ NK/T-cell LPDs exist on a biological continuum of viral oncogenesis. The integration of clinical, pathological, and molecular information aims to create a more accurate classification system, enabling better risk evaluation and tailored treatment strategies for patients with these complex disorders. Full article

Myeloid neoplasms (MNs) with germline predisposition represent a distinct, increasingly recognized category in the WHO classification, encompassing myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) arising in the context of an inherited genetic alteration or mutation. While often presenting at a younger age or with characteristic cytopenias with or without organ dysfunction, some can manifest in adulthood, highlighting the need for vigilance regardless of age or family history. Key predisposing genes include transcription factors (e.g., RUNX1, CEBPA) and genes involved in RNA splicing and telomere biology disorders. Identification of these germline mutations is critical as MNs with germline predisposition dictate specific therapeutic strategies—particularly for hematopoietic stem cell transplantation (HSCT)—and require genetic counseling and surveillance for at-risk relatives. Accurate diagnosis often requires non-hematopoietic germline DNA testing, which provides important biological insights into the development of different myeloid neoplasms and directs personalized patient care. Full article

The SARS-CoV-2 nucleocapsid protein (Np) plays multifunctional roles in the viral life cycle. By interacting with host cellular proteins, Np regulates viral RNA transcription, replication, and immune evasion. It controls genome packaging and counteracts host RNA interference mediated antiviral responses through its RNA binding activity. Previous studies revealed a physical interaction between Np and DDX3X, a human DEAD-box RNA helicase that facilitates the replication of several viruses. This interaction enhances Np affinity for double-stranded RNA and inhibits DDX3X helicase activity. Since Np-RNA binding activity promotes ribonucleoprotein complex formation, targeting this interaction is a promising antiviral strategy. We generated truncated protein variants to define interaction regions between Np and DDX3X. Using AlphaFold modelling, we identified RecA2 as the key DDX3X domain involved in Np binding. Finally, to disrupt Np-RNA complex formation, we screened a small molecule library of putative binders of Np N-terminal region and identified two candidate inhibitors for further development. Full article

Background: Colorectal cancer (CRC) is a leading cause of cancer death, and the incidence and mortality rates among young adults are rising. Although a subset of CRC cases presents with a family history, suggesting a hereditary component, the specific genetic underpinnings remain incompletely understood, particularly in early-onset CRC (EOCRC). This study aimed to discover novel risk genes for EOCRC using exome sequencing and gene-based rare variant burden testing. Methods: Our cohort consisted of 212 European-ancestry cases (174 diagnosed with CRC and 38 with significant polyps) from the South Australian Young Onset Colorectal Polyp and Cancer Study (SAYO) and 31,699 unaffected controls from the Simons Foundation Powering Autism Research for Knowledge (SPARK) cohort. After filtering for ancestry, relatedness, variant quality, and population allele frequency, we performed gene-set and individual-gene burden tests using predicted deleterious missense and loss-of-function variants. Statistical significance was assessed using permutation-corrected binomial testing. An independent validation was conducted in the UK Biobank. Results: Loss-of-function variants in known CRC tumor suppressor genes were significantly enriched in SAYO cases. Gene-level analyses identified MEIKIN as a novel EOCRC susceptibility candidate (p value = 1.0 × 10⁻⁷), with supporting enrichment of deleterious missense and loss-of-function variants in distal colon cancer cases from the UK Biobank. Additional genes (STK25, PGBD4, DIRAS3, ATG3, RPS6KA4, and DDX42) demonstrated borderline significance, implicating pathways related to kinetochore assembly, autophagy regulation, and immune signaling. Both predicted gain-of-function and loss-of-function variants contributed to the EOCRC risk, supporting heterogeneous mechanisms of CRC pathogenesis. Conclusions: This study identified novel candidate risk genes for EOCRC, underscoring the role of rare variants and expanding our understanding of the genetic architecture of CRC. Future studies should include functional validation and replication studies on other ancestries to confirm and extend these results. Full article