Search Results (566)

Background: Retinoblastoma (RB) is the most common pediatric ocular tumor that occurs due to the biallelic inactivation of the RB1 tumor suppressor gene. RB may be unilateral or bilateral and is hereditary in 50% of cases. An inactivation of the RB1 gene may occur due to gross rearrangements (20%) or due to small-length changes (80%): single nucleotide substitutions (SNVs) and insertions/deletions (INDELs). Objectives: Our objective was to study the frequency of the different RB1 variants present in patients with retinoblastoma and to correlate them with the functional domains of the pRb protein and with the clinical presentation. Methods: For this purpose, we analyzed all the clinically validated germline SNVs and INDELs annotated in the database. They were grouped into the pRb domains; contingency tables were made, and figures were constructed to compare the types of variants in the different domains between bilateral and unilateral patients. Results: The number of variants analyzed was 2103; 34% of them were nonsense, 34% INDELs, 22% splice-site and 10% missense. All these variants mainly gave rise to bilateral RB (88%); their frequency and distribution in relation to pRb domains varied between bilateral (Bi) and unilateral hereditary (Ug) RB. Nonsense variants occurred more frequently in Bi vs. Ug, whereas missense variants were more frequent in Ug vs. Bi. Indels and splice-site variants were not significantly different between Bi and Ug. The most frequent pRB location of variants was in the Pocket domain (the binding site of the E2F transcription factor). The slice-site of the consensus sequence most mutated was the first nucleotide of the donor, which is the driver of the splicing process. Conclusions: The highest percentage of variants in RB corresponded to nonsense substitutions and indels, mainly affecting the Pocket domain, which is the major functional site for the pRb regulatory process. These results indicate the predominance of the most pathogenic variants related to the bilateral presentation of retinoblastoma. Full article

The phosphodiesterase 1 genes PDE1A, PDE1B, and PDE1C encode calcium-regulated cyclic nucleotide phosphodiesterases that mediate the interplay between calcium and cyclic nucleotide signaling in the brain, heart, and vasculature. While an inhibitory domain and a calmodulin-binding domain have been identified in PDE1, the mechanism of regulation is not understood. In this study, we investigated the regulatory mechanism through a series of experiments. The experimental data, supported by AlphaFold structure predictions, consistently point to the following model of PDE1 regulation: In the absence of calcium, the inhibitory domain of PDE1 binds to and blocks the catalytic site via molecular interactions that closely resemble those observed in autoinhibited PDE4. Upon calcium/calmodulin binding to PDE1’s calmodulin-binding domain, steric constraints prevent the inhibitory domain from reaching the catalytic site, thereby activating PDE1. Understanding this mode of PDE1 regulation may open new avenues for pharmacological intervention. Moreover, it establishes PDE1 and PDE4 as a second mechanistic class of phosphodiesterase regulation in addition to the GAF-domain-mediated regulation known to control the activity of several other PDEs. Full article

This study investigated the therapeutic potential of a novel probiotic combination consisting of Lactococcus cremoris subsp. cremoris MP01 and Lacticaseibacillus paracasei subsp. paracasei MP02, collectively referred to as LCP, in the treatment of canine atopic dermatitis (CAD). In a 60-day open-label, single-arm trial involving eight dogs, notable clinical improvements were observed following daily LCP treatment, as evidenced by decreasing trends in Canine Atopic Dermatitis Extent and Severity Index and Pruritus Visual Analogue Scale scores, as well as a significant reduction in serum immunoglobulin E levels (p < 0.05). Microbiome and short-chain fatty acid (SCFA) analyses were subsequently conducted in a representative subset of six dogs to explore the effects of LCP on the fecal and skin microbial ecosystems. Concomitant alterations in gut and skin microbiome were observed, including a significant reduction in abundance of Erysipelotrichaceae (p < 0.05) and non-significant decreasing trends in Romboutsia, Escherichia/Shigella spp., and Shigella flexneri, along with a trend toward increased SCFA production. Functional prediction using PICRUSt suggested potential involvement of immune- and infection-related signaling pathways, including those associated with nucleotide-binding oligomerization domain-like receptors, retinoic acid-inducible gene I-like receptors and Shigellosis, supporting the hypothesis that LCP may exert its effects through modulation of the gut–skin axis. These findings support LCP as a safe and promising adjunct therapy for CAD, offering a novel microbiome-targeted approach targeting both clinical symptoms and underlying dysbiosis. Further investigation is warranted to optimize probiotic formulations and better understand the mechanisms underlying microbiome-mediated immune modulation in canine allergy. Full article

Excretory/secretory products from parasites (ESPs) can act as pathogen-associated molecular patterns (PAMPs) to activate innate immunity. Parasites may achieve immune evasion by modulating the interaction between PAMPs and the nucleotide-binding oligomerization domain-like receptor family, pyrin domain-containing three (NLRP3) inflammasome. Previous studies have suggested that some components of ESPs from Clonorchis sinensis (CsESPs) can induce the host’s immune responses, but the components that balance immunopathology and maintain chronic infection in chronic Clonorchis sinensis (C. sinensis) remain unclear. We previously found that the iNOS-interacting protein from C. sinensis (CsNOSIP), a component of CsESP, stimulates macrophages to produce reactive oxygen species (ROS) and nitric oxide (NO), both of which inhibit NLRP3 inflammasome activation. Therefore, this study investigated the effects of CsESP and CsNOSIP on inflammasome activation using RT-PCR, Western blot, and ELISA. This study showed that CsESPs promoted NLRP3 inflammasome activation in RAW264.7 cells, while CsNOSIP inhibited LPS-induced IL-1β secretion through an NLRP3-caspase-1-dependent pathway and reversed the CsESPs-induced activation through the iNOS/NO–NF-κB pathway. These results reveal the antagonistic effects of CsESPs and CsNOSIP in inflammasome regulation, suggesting that this balance contributes to the regulation of the host’s immunity and the promotion of chronic infection of C. sinensis, providing potential targets for prevention and treatment. Full article

Capsicum annuum (pepper) is a globally significant Solanaceous crop vulnerable to devastating pathogens such as Phytophthora capsici. Nucleotide-binding leucine-rich repeat (NLRs) proteins are crucial intracellular immune receptors mediating effector-triggered immunity (ETI). This study presents the comprehensive genome-wide identification and analysis of the NLR gene family in pepper using the high-quality ‘Zhangshugang’ reference genome. We identified 288 high-confidence canonical NLR genes. Chromosomal distribution analysis showed significant clustering, particularly near telomeric regions, with Chr09 harboring the highest density (63 NLRs). Evolutionary analysis demonstrated that tandem duplication is the primary driver of NLR family expansion, accounting for 18.4% of NLR genes (53/288), predominantly on Chr08 and Chr09. Analysis of promoter cis-regulatory elements (CREs) revealed enrichment in defense-related motifs, with 82.6% of promoters (238 genes) containing binding sites for salicylic acid (SA) and/or jasmonic acid (JA) signaling. Transcriptome profiling of Phytophthora capsici-infected resistant (C. annuum cv. CM334) and susceptible (C. annuum cv. NMCA10399) cultivars identified 44 significantly differentially expressed NLR genes, and protein–protein interaction (PPI) network analysis predicted key interactions among them, with Caz01g22900 and Caz09g03820 as potential hubs. This study elucidates the tandem-duplication-driven expansion, domain-specific functional implications, and expression dynamics of the pepper NLR family. It identifies conserved and lineage-specific candidate NLR genes, including Caz03g40070, Caz09g03770, Caz10g20900, and Caz10g21150. These findings provide valuable candidate gene targets for the development of molecular markers for pepper resistance to Phytophthora capsici. Full article

Argonaute (Ago) proteins are ubiquitous across all domains of life. Some prokaryotic Agos (pAgos) function as endonucleases that utilize short nucleic acid guides to recognize and cleave complementary targets. Yet, considerable diversity within pAgos leaves many of their biochemical and functional features insufficiently understood. This study characterizes CalAgo, an pAgo from the mesophilic bacterium Cohnella algarum, which demonstrates DNA-guided DNA endonuclease and RNA endonuclease activities at physiological temperatures. CalAgo’s cleavage activity depends on Mn²⁺ and Mg²⁺ ions and remains effective across a wide range of temperatures and pH levels. CalAgo utilizes only short guides ranging from 15 to 21 nucleotides (nt) in length, in contrast to other reported pAgos that target both DNA and RNA, which often exhibit broad guide selectivity. CalAgo preferentially loads 5′-phosphorylated guides and shows no significant preference among guides with different 5′-end nucleotides. CalAgo is sensitive to guide–target mismatches, and introducing a single mismatch at positions 12 or 15 of the guide strand abolished detectable activity. Structural modeling suggests that this unique guide specificity may originate from structural features in its PAZ domain involved in 3′-guide binding. In summary, this study deepens insight into mesophilic pAgos and supports their potential utility in nucleic acid-based applications. Full article

Background/Objectives: This review article highlights the role of the nucleotide-binding domain, leucine-rich repeat, pyrin domain-containing 3 protein (NLRP3) inflammasomes in various gastrointestinal and hepatic disorders in the pediatric age group. NLRP3 inflammasomes are one of the principal intracellular innate immune sensors. During inflammation, molecules such as caspase-1 and the release of IL-1β and IL-18 are produced. The NLRP3 inflammasome participates in the preservation of intestinal homeostasis and mucosal immune response. The objective is to evaluate the published articles related to the role of NLRP3 inflammasomes in common pediatric gastrointestinal and hepatic disorders in order to identify the future perspective regarding their possible therapeutic values. Methods: We searched Medline for NLRP3 inflammasomes and disorders of the digestive system during childhood. Results: Although the majority of articles were related to various disorders of adults, such as Alzheimer’s disease, Parkinson’s disease, atherosclerosis, as well as neurodevelopmental disorders, such as schizophrenia, a few published datasets were related to the roles of NLRP3 in the pediatric age group: they addressed autism, rheumatoid arthritis, and other autoimmune diseases, as well as inflammatory bowel diseases (IBD) and hepatic infection. Some research demonstrated that the NLRP3 inflammasome has a protective role; however, it also has a pathogenic function. Conclusions: This review focused on the comprehensive role of inflammasome NLRP3 in the most common pediatric and neonatal gastrointestinal and hepatic diseases, including clinical and experimental studies, as well as the pharmacological inhibitors for NLRP3 inflammasomes, which may provide future therapy for GIT problems, such as IBD. Full article

Since the appearance of the Severe Acute Respiratory Syndrome (SARS) virus, there has been increased interest in understanding the role of bats in the maintenance and circulation of coronaviruses. This study aimed to describe the phylogenetic and evolutionary relationships and antigenic architecture of a new coronavirus detected in bats in the Department of Córdoba. In a surveillance study of pathogens of interest to public health, a bat Phyllostomus hastatus was captured. Rectal swabs samples were collected from the bats, and RNA was extracted and sequenced using NGS with MGI-G50 equipment. The results were analyzed using bioinformatics software. A contig of 28,619 nucleotides associated with the Coronaviridae family was obtained. Phylogenetic and molecular clock analyses of the ORF1ab gene revealed a novel divergent Alphacoronavirus that originated directly from an ancestral node. The analysis of the spike (S) protein and receptor-binding domain (RBD) is similar to that of humans (HCoV-229E) and porcine coronaviruses. In silico analysis suggests potential RBD interaction sites with human and pig cellular receptor aminopeptidase N. There is a possible risk of interspecies jumping of the new AlphaCoV/P. hastatus in humans and pigs. This is the first study to perform phylogenetic, evolutionary, and antigenic characterization of bat coronaviruses in Colombia. Full article

RNA polymerases are essential enzymes that catalyze DNA transcription into RNA, vital for protein synthesis, gene expression regulation, and cellular responses. Non-template-dependent RNA polymerases, which synthesize RNA without a template, are valuable in biological research due to their flexibility in producing RNA without predefined sequences. However, their substrate polymerization mechanisms are not well understood. This study examines Poly (A) polymerase (PAP), a nucleotide transferase superfamily member, to explore its substrate selectivity using computational methods. Previous research shows PAP’s polymerization efficiency for nucleoside triphosphates (NTPs) ranks ATP > GTP > CTP > UTP, though the reasons remain unclear. Using 500 ns Gaussian accelerated molecular dynamics simulations, stability analysis, secondary structure analysis, MM-PBSA calculations, and Markov state modeling, we investigate PAP’s differential polymerization efficiencies. Results show that ATP binding enhances PAP’s structural flexibility and increases solvent-accessible surface area, likely strengthening protein–substrate or protein–solvent interactions and affinity. In contrast, polymerization of other NTPs leads to a more open conformation of PAP’s two domains, facilitating substrate dissociation from the active site. Additionally, ATP binding induces a conformational shift in residues 225–230 of the active site from a loop to an α-helix, enhancing regional rigidity and protein stability. Both ATP and GTP form additional π–π stacking interactions with PAP, further stabilizing the protein structure. This theoretical study of PAP polymerase’s substrate selectivity mechanisms aims to clarify the molecular basis of substrate recognition and selectivity in its catalytic reactions. These findings offer valuable insights for the targeted engineering and optimization of polymerases and provide robust theoretical support for developing novel polymerases for applications in drug discovery and related fields. Full article

Background/Objectives: Diabetic nephropathy (DN) is a major complication of diabetes and a leading cause of end-stage renal disease, a condition associated with high mortality risks. Recently, supplementation with probiotics and postbiotics has been attracting attention. Especially, metabolites of natural products bioconverted by beneficial bacteria have emerged as a novel therapeutic intervention for metabolic diseases, including diabetes, due to the enhanced bioavailability of their metabolites. This study investigated the alleviating effects of metabolites derived from guava leaf extract bioconverted by Limosilactobacillus fermentum (GBL) on renal inflammation in type 2 diabetic mice. Methods: For this purpose, diabetes was induced in male C57BL/6J mice by a high-fat diet and streptozotocin injection (80 mg/kg BW) twice. Subsequently, mice with fasting blood glucose levels higher than 300 mg/dL were administered metabolites of L. fermentum (LF) (50 mg/kg BW/day) or guava leaf extract bioconverted by L. fermentum (GBL) (50 mg/kg BW/day) by oral gavage for 15 weeks. Results: GBL demonstrated potential in alleviating hyperglycemia-induced DN in diabetic mice. It markedly improved hyperglycemia, glucose tolerance, and morphological alterations, which might stem from activation of key regulators of energy metabolism. GBL uniquely reduced advanced glycation end products (AGEs) and suppressed nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB)-driven inflammatory pathways, which significantly alleviated oxidative stress and apoptosis. Conclusions: This highlights the distinct therapeutic efficacy of GBL in addressing DN, primarily through its effects on renal inflammation. Taken together, GBL can be used as a promising nutraceutical to mitigate hyperglycemia and its associated renal inflammation, thereby alleviating the progression of DN. Full article

Iron is essential for cellular respiration, oxidative defense, and host immunity, but its dysregulation is increasingly associated with metabolic disorders, such as obesity and type 2 diabetes. In these diseases, regional iron accumulation occurs in adipose tissue, independent of systemic overload. This process disrupts the mitochondrial redox balance, induces ferroptotic stress, and activates the innate immune pathways. Recent studies have highlighted the NLRP3 (nucleotide-binding domain, leucine-rich repeat, pyrin domain-containing protein 3) inflammasome and its effector cytokine interleukin-1β (IL-1β) as important mediators of the interface between iron and inflammation. In both adipocytes and macrophages, labile iron increased reactive oxygen species (ROS) production and promoted inflammasome formation. Simultaneously, metabolic stress factors upregulate hepcidin expression, suppress ferroportin activity and exacerbate intracellular iron retention. These molecular events converge to maintain low-grade inflammation and impair insulin signaling. Despite these compelling associations, direct mechanistic evidence remains limited, particularly with respect to depot-specific responses and cell type resolution. In this review, I examine the current evidence linking iron handling and inflammasome biology in adipose tissue, focusing on ferroptosis, thioredoxin-interacting protein (TXNIP) signaling, and spatial mapping of iron–cytokine networks. I also discuss novel therapeutic strategies targeting iron overload and inflammasome activation, including chelation, hepcidin modulation, and inflammasome inhibition in the context of metabolic diseases. Full article

Due to their evolutionary divergence from mammals, zebrafish (Zf, Danio rerio), which are frequently employed in biomedical research, provide a distinctive viewpoint on innate immune systems. The Toll-like receptor 4/myeloid differentiation factor 2/cluster of differentiation 14 (TLR4/MD-2/CD14) complex in mammals detects lipopolysaccharide (LPS), a crucial component of Gram-negative bacteria, and it causes potent inflammatory reactions through a Toll/interleukin-1 receptor domain-containing adapter-inducing interferon-β (TRIF)-dependent and myeloid differentiation primary response 88 (MyD88)-dependent pathways. However, key components of this system, such as a responsive TLR4 axis and a functional CD14 ortholog, are absent in Zf. The Zf species nevertheless reacts to LPS, which leads to research into other recognition systems. This review looks at a number of TLR4-independent processes in Zf, such as scavenger receptors (SRs) including scavenger receptor class B type 1 (SR-BI) and cluster of differentiation 36 (CD36), nucleotide-binding oligomerization domain-containing protein 1 (NOD1)-dependent cytosolic sensing, peptidoglycan recognition proteins (PGRPs), Complement Component 3 (C3), and caspase-1-like protein 2 (Caspy2)-mediated inflammasome activation. An alternative and flexible immune system that makes up for the lack of canonical TLR4 signaling is revealed by these mechanisms. Additionally, the discovery of lymphocyte antigen 96 (ly96), an ortholog of MD-2 found in Zf, suggests evolutionary similarity; however, as it is only functional in artificial systems, it demonstrates minimal overlap with mammalian MD-2 activity. Knowing these pathways provides important information for studying inflammation, infection, and immunological modulation in vertebrates using Zf as a model. It also clarifies the evolutionary flexibility of innate immune recognition. Full article

Wheat powdery mildew, caused by Blumeria graminis f. sp. tritici, represents one of the most threatening biotic stresses of this crop. The cultivated wheat variety ‘Brock’ exhibits resistance not only to rust but also to powdery mildew, making it a valuable resource for exploitation in wheat disease-resistant breeding. This study identified a novel gene in ‘Brock’ distinct from Pm2. In order to identify the disease resistance gene in ‘Brock’, genetic mapping was performed using F₂ and F_2:3 populations derived from the cross ‘Jing411/Brock’. The candidate powdery mildew resistance gene was located within a 6.88 Mb physical interval on chromosome 2D, which harbors a highly expressed gene, TaRPM1-2D. The protein encoded by TaRPM1-2D possesses a typical nucleotide binding, leucine-rich repeat receptor (NLR) domain, and its sequence significantly differs among ‘Jing411’, ‘BJ-1’, and ‘Brock’. Expression of TaRPM1-2D was markedly higher in resistant wheat ‘Brock’ and ‘BJ-1’ compared to the susceptible ‘Jing411’. Both overexpression and gene silencing experiments demonstrated that TaRPM1-2D contributes to enhance resistance against powdery mildew in wheat. These findings reveal the function of TaRPM1-2D in conferring powdery mildew resistance in ‘Brock’ and provide a candidate gene for disease-resistance breeding. Full article

SSB proteins play essential roles in DNA replication, recombination, and repair in bacteria, archaea, and eukarya. This study investigates the transcript levels, identification, expression and purification, subcellular localization, and immune protective potential of the SSB-like proteins of Eimeria necatrix (EnSSB), exploring its role in the development of E. necatrix and its potential as a candidate antigen for a subunit vaccine against avian coccidiosis. The level of EnSSB gene transcription was highest in unsporulated oocysts (UO), followed by gametocytes (GAM) (p < 0.05). The gene consisted of an open reading frame of 1488 nucleotides encoding a protein of 495 amino acid residues with a predicted molecular weight of 53.31 kDa. EnSSB contained a SSB domain with a conserved OB (oligonucleotide/oligosaccharide binding) fold. The molecular mass of the native protein, as determined by Western blot analysis, was ~58 kDa in second-generation merozoites (MZ-2) and UO. In addition to the 58 kDa band, four other bands (~98 kDa, ~82 kDa, ~36 kDa and ~28 kDa) were detected in GAM. No bands were detected in MZ-3. Indirect immunofluorescence and immuno-electron microscopy localized EnSSB in the cytoplasm of macrogametocytes but not in wall-forming bodies and oocyst wall. Animal challenge experiments demonstrated that rEnSSB elicited robust IgY responses, increased splenic T lymphocytes and body weight gain, reduced intestinal lesion scores and oocyst shedding, and presented anticoccidial index (ACI) more than 160. These findings not only offer a foundation for understanding the role of EnSSB protein in regulating the development of E. necatrix, but also present a potential protective antigen of E. necatrix for the development of a subunit vaccine against avian coccidiosis. Full article

Background: Glioblastoma multiforme (GBM) represents one of the most aggressive and lethal primary brain malignancies, characterized by rapid proliferation, extensive invasiveness, and a dismal prognosis. Emerging evidence implicates nucleotide-binding oligomerization domain-containing protein 2 (NOD2), an intracellular pattern recognition receptor, as a potential driver of GBM progression. This study investigates NOD2’s role in promoting glioblastoma through its effects on the epithelial–mesenchymal transition (EMT) and cancer stem cell (CSC) markers. Methods: NOD2 expression levels and survival outcomes were assessed using TCGA data from GBM tumor samples (n = 153) and normal brain tissues (n = 5). NOD2 protein expression was validated in glioma cell lines using Western blot and immunofluorescence analyses. Functional studies employed siRNA-mediated NOD2 knockdown to evaluate effects on cellular proliferation, migration, invasion, and colony formation, while correlations between NOD2 and EMT/CSC markers were assessed. Results: The analysis of TCGA data revealed a significantly elevated NOD2 expression in GBM tumors compared to normal brain tissue, with a high NOD2 expression correlating with a reduced disease-free survival in GBM patients. All tested glioma cell lines demonstrated robust NOD2 expression. Functional analyses demonstrated that NOD2 depletion substantially impaired cellular proliferation, migration, invasion, and the colony-forming capacity. Mechanistically, siRNA-mediated NOD2 knockdown significantly decreased the expression of EMT (Snail, SLUG, Vimentin) and CSC markers (CD44, CD133) at both protein and mRNA levels. Conclusions: Our results indicate that NOD2 contributes to GBM progression by influencing EMT and CSC pathways. These findings suggest NOD2’s potential as a therapeutic target in glioblastoma, highlighting the need for further mechanistic studies and therapeutic exploration. Full article