Search Results (303)

The expanding distribution and geographic range of mosquitoes have potentially contributed to increased flaviviral dissemination and transmission. Despite the growing burden of flaviviral infections, there are no effective antiviral treatments or vaccines, highlighting the need for novel therapeutic targets. Tetraspanins, a superfamily of transmembrane domain glycoproteins involved in cellular organization, signaling, and protein–protein interactions have been recognized as potential mediators of flaviviral infection and transmission. While their roles in vertebrate hosts have been explored, their involvement in flaviviral replication and dissemination within medically important vectors remains poorly understood. In this study, we investigated the role of arthropod tetraspanins in mosquito cells and extracellular vesicles (EVs) derived from cells infected with Zika virus (ZIKV) and dengue virus (serotype 2; DENV2). Among several of the tetraspanins analyzed, only CD151 was significantly upregulated in both mosquito cells and in EVs derived from ZIKV/DENV2-infected cells. RNAi-mediated silencing of CD151 led to a marked reduction in viral burden, suggesting its crucial role in flavivirus replication. Inhibition of EV biogenesis using GW4869 further demonstrated that EV-mediated viral transmission contributes to flavivirus propagation. Additionally, co-immunoprecipitation and immunofluorescence analyses revealed direct interactions between CD151 and ZIKV NS2B and DENV2 capsid proteins. Overall, our findings highlight the functional importance of mosquito CD151 in the replication and transmission of ZIKV and DENV2. This study provides new insights into the molecular mechanisms of flaviviral infection in mosquitoes and suggests that targeting vector tetraspanins may offer a potential approach to controlling mosquito-borne flaviviruses. Full article

Spurred by the enormous therapeutic success of glucagon-like peptide-1 receptor (GLP-1R) agonists (GLP1-RAs) against diabetes and obesity, glucagon family receptor pharmacology has garnered a tremendous amount of interest. Glucagon family receptors, e.g., the glucagon receptor itself (GCGR), the GLP-1R, and the glucose-dependent insulinotropic peptide receptor (GIPR), belong to the incretin receptor superfamily, i.e., receptors that increase blood glucose-dependent insulin secretion. All incretin receptors are class B1 G protein-coupled receptors (GPCRs), coupling to the G_s type of heterotrimeric G proteins which activates adenylyl cyclase (AC) to produce cyclic adenosine monophosphate (cAMP). Most GPCRs undergo desensitization, i.e., uncouple from G proteins and internalize, thanks to interactions with the βarrestins (arrestin-2 and -3). Since the βarrestins can also mediate their own G protein-independent signaling, any given GPCR can theoretically signal (predominantly) either via G proteins or βarrestins, i.e., be a G protein- or βarrestin-“biased” receptor, depending on the bound ligand. A plethora of experimental evidence suggests that the GLP-1R does not undergo desensitization in physiologically relevant tissues in vivo, but rather, it produces robust and prolonged cAMP signals. A particular property of constant cycling between the cell membrane and caveolae/lipid rafts of the GLP-1R may underlie its lack of desensitization. In contrast, GIPR signaling is extensively mediated by βarrestins and the GIPR undergoes significant desensitization, internalization, and downregulation, which may explain why both agonists and antagonists of the GIPR exert the same physiological effects. Here, we discuss this evidence and make a case for the GLP-1R being a phenotypically or functionally G_s-selective receptor. We also discuss the implications of this for the development of GLP-1R poly-ligands, which are increasingly pursued for the treatment of obesity and other diseases. Full article

The enzyme ABH2, one of nine human DNA dioxygenases of the AlkB family, belongs to the superfamily of Fe(II)/α-ketoglutarate-dependent dioxygenases and plays a crucial role in the direct reversal repair of nonbulky alkyl lesions in DNA nucleobases. ABH2 has broad substrate specificity, directly oxidizing DNA damages such as N¹-methyladenine, N³-methylcytosine, 1,N⁶-ethenoadenine, 3,N⁴-ethenocytosine, and a number of others. In our investigation, we sought to uncover the subtleties of the mechanisms governing substrate specificity in ABH2 by focusing on several critical amino acid residues situated in its active site. To gain insight into the function of this enzyme, we performed a functional mapping of its active site region, concentrating on pivotal residues, participating in forming a damaged binding pocket of the enzyme (Val99 and Ser125), as well as the residues directly involved in interactions with damaged bases, namely Arg110, Phe124, Arg172, and Glu175. To support our experimental data, we conducted a series of molecular dynamics simulations, exploring the interactions between the ABH2 mutant forms, bearing corresponding substitutions and DNA substrates, and harboring various types of methylated bases, specifically N¹-methyladenine or N³-methylcytosine. The comparative studies revealed compelling data indicating that alterations in most of the studied amino acid residues significantly influence both the binding affinity of the enzyme for DNA and its catalytic efficiency. Intriguingly, the findings suggest that the mutations impact the catalytic activity of ABH2 to a greater extent than its ability to associate with DNA strands. Collectively, these results show how changes to the active site affect molecular dynamics and reaction kinetics, improving our understanding of the substrate recognition process in this pivotal enzyme. Full article

The BAHD acyltransferase family plays a critical role in plant secondary metabolism by catalyzing acyl transfer reactions that are essential for synthesizing metabolites involved in environmental adaptation. However, systematic investigation of this superfamily in Brassica napus has not been reported. In this study, 158 BnaBAHD genes were identified by comprehensive analyses of evolutionary relationships, motif structures, chromosomal distribution, gene collinearity, and selection pressures, and these genes were phylogenetically classified into five clades harboring conserved catalytic domains (HXXXD and DFGWG). Transient overexpression combined with metabolomic profiling demonstrated that two homologous seed-specific Clade V members, BnaBAHD040 and BnaBAHD120, which exhibited elevated expression during late seed development, significantly enhanced the accumulation of acylated metabolites contributing to biotic/abiotic stress resistance. This study provides the first experimental validation of the catalytic functions of BAHD enzymes in B. napus, establishing a theoretical foundation for leveraging this gene family in genetic improvement to develop novel rapeseed cultivars with enhanced stress tolerance and yield. Full article

The transforming growth factor-beta (TGF-β) superfamily plays a crucial role in regulating female reproductive traits, particularly litter size, in small ruminants, such as sheep and goats. This review comprehensively examines the molecular mechanisms through which TGF-β superfamily members—including bone morphogenetic proteins (BMPs), growth differentiation factor 9 (GDF9), inhibin (INHA and INHB), and associated signaling genes—influence ovarian follicular development, ovulation rate, and ultimately, litter size. We synthesize recent findings on polymorphisms in key genes, such as BMPR1B, BMP15, GDF9, inhibins and SMADs family genes, across diverse sheep and goat breeds worldwide. The manuscript highlights how specific mutations in these genes create an intricate signaling network that modulates granulosa cell proliferation, follicular sensitivity to FSH, and the prevention of dominant follicle selection. These molecular interactions result in increased ovulation rates and larger litter sizes in prolific breeds. The gene dosage effects observed in heterozygous versus homozygous mutation carriers further illuminate the complex nature of these reproductive regulations. This improved the understanding of the genetic basis for prolificacy provides valuable insights for marker-assisted selection strategies aimed at enhancing reproductive efficiency in small ruminant breeding programs, with significant implications for improving livestock productivity and economic outcomes. Full article

Aspergillus flavus, a common food contaminant, poses health and economic risks. Previous research showed that recombinant Puroindoline B protein (rPINB) inhibited A. flavus by disrupting its cell wall, membrane, nuclear function, mitochondrial activity, and oxidative stress. This study used transcriptome technology to explore the impact of rPINB on A. flavus gene expression and created gene deletion strains to test the sensitivity to rPINB. RNA-Seq identified the differentially expressed genes (DEGs) affecting cell wall synthesis, membrane transport, oxidative stress, spore formation, and aflatoxin production. The MFS transporter genes AFLA_106900 (mfs1) and AFLA_106910 (mfs2) were crucial for an inhibitory effect of rPINB. The mutants exhibited reduced sensitivity to rPINB-mediated inhibition, indicating lower growth, sunken conidia, and shriveled hyphae, compared to the wild-type strain. The results also demonstrated decreased sensitivity to the stress agents affecting cell membranes, osmotic balance, and oxidation, alongside a significant reduction in AFB1 production in gene-deleted strains. These results suggested that mfs1 and mfs2 were essential for rPINB protein’s inhibition of A. flavus growth, laying the groundwork for the mold control strategies using plant proteins. Full article

Alpha/beta hydrolase (ABHs) fold esterase/lipase proteins represent a prominent family within the serine hydrolase (SH) superfamily that includes esterases and lipases and other catalytic and non-catalytic proteins. ABHs play crucial roles in both the fundamental and secondary metabolic pathways, including the synthesis and degradation of triacylglycerols (TAGs), key components of plant oils. Despite their importance in oil production, the ABH gene family in the oil crop Brassica napus has not been comprehensively analyzed. In the present study, we identified 777 BnABH genes in the B. napus cultivar ‘Zhongshuang 11’ (ZS11). Phylogenetic analysis categorized these BnABH genes into 10 distinct groups. Twenty-four BnABHs were identified through esterase activity staining and mass spectrometry, 11 of which were classified into clade C3. Examination of the gene and protein structures, expression patterns, and cis-elements of the BnABHs in clade C3 suggested diverse functional roles across different tissues and in response to various environmental stresses. In particular, BnABH205 was highly induced by high temperatures. Subcellular localization analysis revealed that the BnABH205 protein was localized to the plastid. Further analysis revealed five haplotypes within the coding and 3′ untranslated regions of BnABH205 that were significantly associated with seed oil content (SOC). Overall, this study provides a comprehensive understanding of BnABHs and introduces a robust methodology for identifying potential esterase/lipase genes that regulate seed oil content (SOC) in response to environmental hazards, especially heat waves during seed maturation. Full article

The B3 transcription factor superfamily, crucial for plant growth and stress adaptation, remains poorly characterized in cucumber (Cucumis sativus), a globally important vegetable crop. Here, we conducted the first genome-wide identification of 52 B3 superfamily genes in cucumber, classifying them into LAV, ARF, RAV, and REM subfamilies through integrated phylogenetic and structural analyses. These genes exhibited conserved B3 domains with lineage-specific motif architectures and diverse exon–intron organizations, particularly within the structurally divergent REM subfamily. Collinearity analysis revealed segmental duplication as a key driver of family expansion, notably between syntenic REM clusters on chromosomes 2 (CsREM5-7) and 6 (CsREM18-20). Promoter cis-element profiling identified enrichment in hormone-responsive and stress adaptation motifs, suggesting functional diversification in signaling pathways. Furthermore, tissue-specific expression divergence was observed across 10 organs, with ARF members displaying broad regulatory roles and REM genes showing apical meristem enrichment. Strikingly, CsRAV8 exhibited glandular trichome-specific expression, a novel finding, given Arabidopsis RAVs’ lack of trichome-related functions. Spatial validation via in situ hybridization localized CsRAV8 transcripts to trichome glandular head cells. Functional investigation using virus-induced gene silencing (VIGS) demonstrated that CsRAV8 suppression caused significant glandular trichome shriveling, implicating its role in maintaining glandular cavity integrity. This study provides the first comprehensive genomic inventory of B3 transcription factors in cucumber, providing evolutionary insights and functional frameworks for future functional genomics studies. Full article

Background: Pancreatic ductal adenocarcinoma (PDAC), a challenging and malignant cancer, primarily originates from the exocrine cells of the pancreas. The superfamily of solute carrier (SLC) transporters, consisting of more than 450 proteins divided into 65 families, is integral to various cellular processes and represents a promising target in precision oncology. As therapeutic targets, SLC transporters are explored through an integrative analysis. Materials and Methods: The expression profiles of SLCs were systematically analyzed using mRNA data from The Cancer Genome Atlas (TCGA) and protein data from the Human Protein Atlas (HPA). Survival analysis was examined to evaluate the prognostic significance of SLC transporters for overall survival (OS) and disease-specific survival (DSS). Genetic alterations were examined using cBioPortal, while structural studies were performed with AlphaFold and AlphaMissense to predict functional impacts. Furthermore, Gene Set Enrichment Analysis (GSEA) was carried out to identify oncogenic pathways linked to SLC transporter expression. Results: SLC transporters were significantly upregulated in tumors relative to normal tissues. Higher expression levels of SLC39A10 (HR = 1.89, p = 0.0026), SLC22B5 (HR = 1.84, p = 0.0042), SLC55A2 (HR = 2.15, p = 0.00023), and SLC30A6 (HR = 1.90, p = 0.003) were strongly associated with unfavorable OS, highlighting their connection to poor prognosis in PDAC. GSEA highlighted that these four transporters are significantly involved in key oncogenic pathways, such as epithelial–mesenchymal transition (EMT), TNF-α signaling, and angiogenesis. Conclusions: The study identifies four SLCs as therapeutic targets in PDAC, highlighting their crucial role in essential metabolic pathways. These findings lay the groundwork for developing next-generation metabolic anti-cancer treatment to improve survival for PDAC patients. Full article

Hepatocyte nuclear factor 4α (HNF4α), a highly conserved member of the nuclear receptor superfamily of transcription factors, has been identified as a promising therapeutic candidate for colorectal adenocarcinoma (CRAC). This study was to investigate the significance of HNF4α in CRAC and mechanisms governing its function. The expression patterns and clinical relevance of HNF4α were evaluated in relation to nuclear factor kappa B (NF-κb), Yes-associated protein (YAP), and epithelial–mesenchymal transition markers. HNF4α exhibited upregulation during carcinogenesis compared to normal and precancerous lesions. The overexpression and inhibition of HNF4α were correlated with the modulation of CRAC cell migration and invasion, either promoting or suppressing these processes. Notably, levels of HNF4α were significantly diminished in metastatic and poorly differentiated CRAC relative to primary CRAC samples. Moreover, reduced HNF4α levels were associated with unfavorable prognostic factors. The inhibition of HNF4A induced a decrease in NF-κb protein levels, concomitant with an increase in YAP. Our results indicate a dual role of HNF4α in tumor progression, either as a promotor or inhibitor, depending on the pathologic condition of CRAC and the related signaling pathways. HNF4α exhibits a complex role, whereby its overexpression is linked to early carcinogenesis and reduced expression is associated with the progression and metastasis of CRAC. Full article

Background/Objectives: Phosphodiesterase 7 (PDE7), a member of the PDE superfamily, selectively catalyzes the hydrolysis of cyclic adenosine 3′,5′-monophosphate (cAMP), thereby regulating the intracellular levels of this second messenger and influencing various physiological functions and processes. There are two subtypes of PDE7, PDE7A and PDE7B, which are encoded by distinct genes. PDE7 inhibitors have been shown to exert therapeutic effects on neurological and respiratory diseases. However, FDA-approved drugs based on the PDE7A inhibitor are still absent, highlighting the need for novel compounds to advance PDE7A inhibitor development. Methods: To address this urgent and important issue, we conducted a comprehensive cheminformatics analysis of compounds with potential for PDE7A inhibition using a curated database to elucidate the chemical characteristics of the highly active PDE7A inhibitors. The specific substructures that significantly enhance the activity of PDE7A inhibitors, including benzenesulfonamido, acylamino, and phenoxyl, were identified by an interpretable machine learning analysis. Subsequently, a machine learning model employing the Random Forest–Morgan pattern was constructed for the qualitative and quantitative prediction of PDE7A inhibitors. Results: As a result, six compounds with potential PDE7A inhibitory activity were screened out from the SPECS compound library. These identified compounds exhibited favorable molecular properties and potent binding affinities with the target protein, holding promise as candidates for further exploration in the development of potent PDE7A inhibitors. Conclusions: The results of the present study would advance the exploration of innovative PDE7A inhibitors and provide valuable insights for future endeavors in the discovery of novel PDE inhibitors. Full article

The human APOBEC superfamily consists of eleven cytidine deaminase enzymes. Among them, APOBEC3 enzymes play a dual role in antiviral immunity and cancer development. APOBEC3 enzymes, including APOBEC3A (A3A) and APOBEC3B (A3B), induce mutations in viral DNA, effectively inhibiting viral replication but also promoting somatic mutations in the host genome, contributing to cancer development. A3A and A3B are linked to mutational signatures in over 50% of human cancers, with A3A being a potent mutagen. A3B, one of the first APOBEC3 enzymes linked to carcinogenesis, plays a significant role in HPV-associated cancers by driving somatic mutagenesis and tumor progression. The A3A_B deletion polymorphism results in a hybrid A3A_B gene, leading to increased A3A expression and enhanced mutagenic potential. Such polymorphism has been linked to an elevated risk of certain cancers, particularly in populations where it is more prevalent. This review explores the molecular mechanisms of APOBEC3 proteins, highlighting their dual roles in antiviral defense and tumorigenesis. We also discuss the clinical implications of genetic variants, such as the A3A_B polymorphism, mainly in HPV infection and associated cancers, providing a comprehensive understanding of their contributions to both viral restriction and cancer development. Full article

Idiopathic pulmonary fibrosis (IPF) is a progressive and incurable chronic interstitial lung disease characterized by excessive fibrosis and impaired lung function. Current treatments, such as pirfenidone and nintedanib, slow disease progression but fail to halt or reverse fibrosis, highlighting the need for novel approaches. Activin A, which belongs to the TGF-β superfamily, is implicated in various fibrosis-related mechanisms, including epithelial–mesenchymal transition (EMT), a process where epithelial cells acquire mesenchymal characteristics, and fibroblast–myofibroblast transformation (FMT), in which fibroblasts differentiate into contractile myofibroblasts. It also promotes inflammatory cytokine release and extracellular matrix buildup. This study aimed to inhibit Activin A activity using synthetic peptides identified through phage display screening. Of the ten peptides isolated, A7, B9, and E10 demonstrated high binding affinity and inhibitory activity. Computational modeling confirmed that these peptides target the receptor-binding domain of Activin A, with peptide E10 exhibiting superior efficacy. Functional assays showed that E10 reduced cell migration, inhibited EMT in A549 cells, and suppressed FMT in fibroblast cultures, even under pro-fibrotic stimulation with TGF-β. These findings underscore the therapeutic potential of targeting Activin A with synthetic peptides, offering a promising avenue for IPF treatment and expanding the arsenal of anti-fibrotic strategies. Full article

Aegilops tauschii, a monocotyledonous annual grass, recognized as a pivotal progenitor of modern wheat (Triticum aestivum L.), serves as the D-genome donor in hexaploid wheat. This diploid species (2n = 2x = 14, DD) harbors a substantial reservoir of genetic diversity, particularly in terms of biotic and abiotic stress resistance traits. The extensive allelic variation present in its genome has been increasingly utilized for wheat genetic enhancement, particularly through introgression breeding programs aimed at improving yield potential and stress resilience. Heavy metal ATPases (HMAs), which belong to the P-type ATPase superfamily and are also known as P1B-type ATPases, play a crucial role in transporting heavy metals and maintaining metal ion homeostasis in plant cells. HMAs have been extensively studied in model plants like Arabidopsis thaliana and rice. However, this family has not been reported in A. tauschii. Here, we conducted the genome-wide identification and bioinformatics analysis of the AetHMA gene family in A. tauschii, resulting in the discovery of a total of nine AetHMA members. Among AetHMA genes, six pairs are large-block duplication genes, which mainly occur among the four genes of AetHMA2, AetHMA4, AetHMA8, and AetHMA9. Additionally, there is one pair that consists of tandem duplication genes (AetHMA6: AetHMA7). All AetHMAs can be classified into six groups (I–VI), which are further divided into two branches: the copper subclasses and the zinc subclasses. Initially, A. tauschii was grown in a 1/2 Hoagland nutrient solution and subsequently exposed to four heavy metals: zinc (Zn), copper (Cu), manganese (Mn), and cadmium (Cd). Following this treatment, the expression profiles of nine AetHMA genes were assessed. The results indicated that, under zinc and manganese stress, the HMA family members exhibited enhanced expression in the leaves, whereas the expression of most members in the roots was downregulated. In the roots, except for AetHMA2, AetHMA5, and AetHMA8, the expression levels of other members were upregulated in response to Cd exposure. Furthermore, AetHMA4 diminishes the tolerance of yeast to Mn by increasing the absorption of Mn, while AetHMA8 increases the tolerance of yeast to Cd by reducing the absorption of Cd. This study provides experimental data regarding the function of the AetHMA gene in the transport, regulation, and detoxification of heavy metal elements in A. tauschii. Full article

Background/Objectives: Recent interest in dietary components and their effects on xenobiotic metabolism has highlighted their role in modulating drug pharmacokinetics. Cytochrome P450 3A4, a key isoform of the cytochrome P450 superfamily, is involved in the metabolism of over 50% of xenobiotics. Flavonoids, present in various foods and supplements, exhibit diverse biological activities influenced by the structural modifications in their scaffold. Methods: Fifteen polyhydroxy-flavonoid compounds were firstly tested by a high-throughput fluorimetric method for their ability to inhibit CYP3A4, where scutellarein and gossypetin were assessed for the first time. A molecular docking analysis was performed for the most active inhibitors to gain insight on their interaction with the active site of the enzyme. Results: Baicalein, luteolin, and scutellarein were the most potent flavones, presenting an IC₅₀ of 15 ± 5, 31 ± 10, and 19 ± 7 μmol/L, respectively. Gossypetin, herbacetin, and quercetin were the most potent flavonols with IC₅₀ of 40 ± 8, 32 ± 8, and 23 ± 5 μmol/L, respectively. The molecular docking analysis showed that hydroxyl groups at C6, C7, C8 (ring A), and C3’ (ring B) on the flavone structure affect CYP3A4 enzyme catalysis by binding to its substrate-binding site as strong as known antiviral and antifungal drugs. Conclusions: Binding to the enzyme’s active site with a strength comparable to known antifungal and antiviral drugs, baicalein and scutellarein were identified as the most active flavonoids. The vicinal hydroxyls in those molecules were pivotal to positioning and stabilization in the catalytic site pocket. Full article