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Results for “differential peptide expression”

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At least 19 recordsLinked to original sources

PubMed2026

Molecular mechanisms underlying umami taste perception: A DIA-based proteomic analysis of Agrocybe aegerita peptides.

The mechanisms underlying the modulation of the salivary perception of umami peptides remain poorly understood. Herein, three umami peptides (DDL, DEL, and ENG) obtained from Agrocybe aegerita were used to investigate the regulatory role of saliva in umami taste perception via a combined approach involving sensory evaluation and proteomics analysis based on 4D-DIA technology. The results revealed that umami intensity peaked at 10 s after ingestion and was accompanied by a significant increase in saliva secretion (p < 0.05). Further proteomics analysis revealed that lactotransferrin and proline-rich proteins are closely associated with the sensory perception of umami peptides. Differentially expressed proteins were mainly enriched in pathways related to saliva secretion and proteasome function. This study provides new insights from the perspectives of salivary proteomics and dynamic salivary secretion, contributing to a deeper understanding of the mechanisms by which saliva regulates umami perception.

Humans↗

PubMed2025

Sex differences in cerebrospinal fluid proteomics of patients with restless legs syndrome.

STUDY OBJECTIVES: The pathobiology of restless legs syndrome (RLS) remains poorly understood, complicating effective treatment. This observational cross-sectional study aimed to identify a cerebrospinal fluid proteomic signature of RLS and to explore sex-specific differences in cerebrospinal fluid proteomics. METHODS: Cerebrospinal fluid samples were collected from 22 untreated RLS patients and 18 controls, matched for age, body mass index, and sex. Proteomic analysis was conducted using the SOMAscan platform, assessing over 7000 peptides. RESULTS: Eight proteins were differentially abundant between patients and controls, with CRP and JAML increased, and TAPBPL and IL1RL1 decreased. Pathway analysis highlighted significant involvement in immune response, coagulation, and cytoskeletal regulation. Analyses were then carried out using sex stratification, comparing men and women separately. Sex-specific analyses revealed more pronounced proteomic alterations in males (68 differentially abundant proteins vs. control males) than in females (17 proteins). Gene enrichment analysis revealed that men with RLS had more involvement in gene regulation and epigenetic factors than control males and women with restless legs syndrome had greater involvement in systemic inflammatory and vascular processes than control females. CONCLUSIONS: This study identified a cerebrospinal fluid proteomic signature in RLS, implicating immune and inflammatory pathways in the disease's pathophysiology. Significant sex differences in protein level suggest potential sex-specific mechanisms in RLS, warranting further investigation. These findings contribute to the current understanding of RLS and could inform future therapeutic strategies.

Humans↗

PubMed2026

Comparative proteomics reveals distinct functions and localization of invasive Entamoeba histolytica and non-invasive Entamoeba moshkovskii proteins.

BACKGROUND: Entamoeba histolytica is a pathogenic protozoan accountable for amoebiasis, while Entamoeba moshkovskii is considered non-invasive. Despite morphological similarity, the molecular mechanisms underlying their different pathogenicity remain largely undefined. METHODS: Trophozoite proteins from axenic cultures of E. histolytica and E. moshkovskii were separated and identified using GeLC-MS/MS, and classified using Gene Ontology. Selected and differentially expressed proteins were validated by peptide-specific antibody production, ELISA, and immunofluorescence to determine cellular localization. RESULTS AND DISCUSSION: A total of 1,077 and 1,201 proteins were identified from E. histolytica and E. moshkovskii, respectively. The 801 of Entamoeba common proteins included kinases, GTPase-activating proteins, and heat shock proteins, reflecting conserved cellular processes. E. histolytica-unique proteins involved in nitrogen compound metabolism, vesicle-mediated transport, and catalytic activities, whereas E. moshkovskii proteins were related to lipid metabolism and environmental resilience. Subcellular localization revealed species-specific distribution of MmpL and AIG1-family proteins, suggesting potential roles in pathogenicity and host-immune response. A large proportion of hypothetical proteins was identified, highlighting gaps and opportunities for future study. CONCLUSIONS: Our study highlights conserved and divergent functions and cellular locations of Entamoeba species-specific proteins as insights for distinct pathogenicity and adaptation. MmpL and AIG1 proteins were proposed as potential targets for further diagnostic and therapeutic development.

Proteomics↗

PubMed2026

Integrated LiP-MS and quantitative proteomics reveal coordinated alterations in protein conformation and expression across tumor and peritumoral regions in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) exhibits substantial molecular heterogeneity, yet protein-level alterations beyond abundance remain insufficiently characterized. Here, we integrated limited proteolysis mass spectrometry (Lip-MS) with 4D label-free quantitative proteomics to investigate conformational accessibility and protein abundance across tumor, peritumoral-near, and peritumoral-far tissues from HCC patients. Differential LiP peptides identified by both DDA and DIA corresponded to 725, 674, and 33 differentially conformed proteins in the Tumor vs. Peritumor-far, Tumor vs. Peritumor-near, and Peritumor-near vs. Peritumor-far comparisons, respectively. Quantitative proteomics identified 405, 365, and 4 differentially expressed proteins in the corresponding comparisons. Integrated analysis identified 488 and 469 conformation-specific altered proteins (CSAPs), which showed altered conformational accessibility without significant abundance changes, and 237 and 205 conformation-expression coupled proteins (CECPs) in the two tumor-involved comparisons. LiP peptide and protein abundance changes were positively correlated, with Spearman coefficients of 0.69-0.72, and more than 99% of CECPs showed concordant directions. Among them, 169 region-conserved CECPs (rcCECPs) were predominantly associated with metabolic and redox-related pathways. Protein-protein interaction analysis identified 30 hub rcCECPs. ACLY, ALDH18A1, GMPS, and DHX9 showed increased representative LiP peptide signals and protein abundance, elevated transcript expression in HCC, and associations with poorer overall survival. Peptide mapping further localized their differential LiP signals to specific sequence regions and annotated domains. Collectively, these findings provide an integrated view of regional conformational accessibility and protein abundance alterations in HCC and identify candidate proteins for further structural and functional investigation.

Humans↗

PubMed2026

Proteomic patterns according to ejection fraction: an EMPEROR-programme analysis.

AIMS: Left ventricular ejection fraction (LVEF) has been incorporated as an inclusion criterion in HF trials. Patient's characteristics, event risk, and treatment response vary according to LVEF. A better understanding of the biological processes across LVEF is warranted. To study proteomic biomarker expression across LVEF using data from the EMPEROR-Programme. METHODS: Two thousand two hundred and fifty-four patients who had proteomic measurements available using 1134 proteins overlapping between the Explore 1536 and 3072 Olink® platforms were included. Main analyses were performed within the EMPEROR-Preserved dataset due to differences in entry criteria between EMPEROR-Preserved and EMPEROR-Reduced with higher entry N-terminal pro B-type natriuretic peptide (NT-proBNP) levels that varied by LVEF cut-offs in the latter. Protein concentrations were compared using ordinal logistic regression across LVEF categories: 41%-49%, 50%-59%, and ≥60%. The resulting β-coefficient indicates the change in the log-odds for the outcome of being in a lower LVEF category for every NPX unit in log2 scale. Analyses were adjusted for covariates and a false-discovery-rate (FDR) correction was applied. RESULTS: A total of 297 proteins exhibited a trend of expression across LVEF categories in EMPEROR-Preserved after adjustment for potential confounders and correction for test multiplicity. Of these, the top 10 proteins were: NT-pro BNP (β = 0.18, 95% CI 0.09-0.27), Wnt inhibitory factor-1 (β = 0.40, 95% CI 0.19-0.61), sialomucin core protein 24 (β = 0.48, 95% CI 0.22-0.74), phospholipid transfer protein (β = 0.38, 95% CI 0.17-0.59), natriuretic peptides B (β = 0.13, 95% CI 0.06-0.20), intercellular adhesion molecule 5 (β = 0.31, 95% CI 0.14-0.49), neural cell adhesion molecule 2 (β = 0.45, 95% CI 0.19-0.70), neural cell adhesion molecule L1-like protein (β = 0.45, 95% CI 0.19-0.71), interactor protein for cytohesin exchange factors 1 (β = 0.12, 95% CI 0.05-0.19), and 3-ketoacyl-CoA thiolase, peroxisomal (β = 0.17, 95% CI 0.07-0.26). The correlation between these proteins and LVEF was generally weak (Rho ≤0.2). CONCLUSIONS: Within EMPEROR-Preserved, the top differentially expressed circulating proteins suggest that pathways related to natriuretic peptides, cell-adhesion, and clonal haematopoiesis are overexpressed at mildly-reduced ejection fraction, but none of the proteins passed the 5%FDR cut-off, and the correlation between circulating proteins and LVEF was weak. These findings suggest that circulating proteins may not be a good discriminant of ejection fraction.

Humans↗

PubMed2026

Characteristics of Protein Profiling and Biomarkers in Aortic Regurgitation With Heart Failure.

BACKGROUND: Valvular heart disease, particularly aortic valve disease including stenosis and regurgitation, is a common heart disease. This study aimed to explore the protein profiling and the biomarkers in severe aortic valve disease and to provide new insights into the therapeutic strategy. METHODS: Blood samples from 80 subjects were collected and analyzed by data independent acquisition technique in 3 comparisons (mild/moderate-control, severe-control, and severe-mild/moderate) and validated by ELISA. The diagnostic value of differentially expressed proteins associated with severe valvular heart disease was also evaluated by the receiver operating characteristic curve. RESULTS: A total of 9976 peptides and 451 proteins were identified through liquid chromatography-tandem mass spectrometry analysis. From these, 64 in mild/moderate-control, 50 in severe-control, and 50 in severe-mild/moderate comparisons were identified as differentially expressed proteins. IGFBP7 (insulin-like growth factor-binding protein 7; 5581.0±697.0 ng/mL), DSG1 (desmoglein-1; 21.0±2.0 pg/mL), ADIPOQ (adiponectin; 26 686.0±3730 ng/mL), and JUP (junction plakoglobin; 10.2±0.6 ng/mL) levels in the severe group were significantly higher than that in the mild/moderate (P<0.05) group. Additionally, ADIPOQ and JUP levels in the severe group were also higher than that in control (P<0.001). Receiver operating characteristic curve analysis showed that IGFBP7, DSG1, JUP, and ADIPOQ had strong potential value to be associated with severe aortic valve disease. CONCLUSIONS: By constructing proteomics profile to identify the protein characteristics this study found that increased IGFBP7, DSG1, JUP, and ADIPOQ are the characteristics of proteins in patients with severe valvular heart disease. These findings provide new insight into the diagnosis and pathogenesis of valvular heart disease, particularly aortic valve disease.

Humans↗

PubMed2026

Sex-Specific Renal Proteomic Responses to Mycotoxins and Their Mitigation by Bioactive Food Ingredients.

This study aimed to evaluate sex-related differences in kidney toxicity induced by aflatoxin B1 (AFB1) and ochratoxin A (OTA), administered either individually or in combination, and to investigate the mitigating potential of fermented whey (FW) and pumpkin (P) using a proteomic approach in a sub-chronic rat model. Diets naturally contaminated with AFB1 and OTA fungal producers, or enriched with FW and P, were administered to 120 Wistar rats for 28 days. Afterwards, kidneys were collected and subjected to protein extraction and digestion to peptides. For proteomic analysis, peptides were separated using an LC-QTOF-MS system, and differentially expressed proteins between control and treated groups were statistically filtered (p < 0.05) to distinguish sex-related differences between males and females. Proteomic analysis revealed that non-supplemented diets induced significant protein alterations, with male kidneys showing greater sensitivity to mycotoxin exposure, particularly to OTA, and exhibiting a distinct expression pattern compared with females. Notably, FW and FW + P supplementation mitigated these adverse effects by reducing the number of differentially expressed proteins, stabilizing mitochondrial function, and enhancing xenobiotic metabolism pathways. These findings underscore the importance of sex-specific factors in evaluating the protective potential of bioactive ingredients against mycotoxin-induced renal injury.

Animals↗

PubMed2025

Functional genomics of trypanotolerant and trypanosusceptible cattle infected with Trypanosoma congolense across multiple time points and tissues.

Human African trypanosomiasis (HAT), or sleeping sickness, is a neglected tropical disease caused by infection with trypanosome parasites (Trypanosoma spp.). These are transmitted by infected tsetse flies (Glossina spp.) and cause a similar disease in animals, known as African animal trypanosomosis (AAT), which is one of the largest constraints to livestock production in sub-Saharan Africa and causes a financial burden of approximately $4.5 billion annually. Some African Bos taurus cattle populations have an important evolutionary adaptation known as trypanotolerance, a genetically determined tolerance of infection by trypanosome parasites (Trypanosoma spp.). Trypanotolerant African B. taurus N'Dama and trypanosusceptible Bos indicus Boran cattle responded in largely similar ways during trypanosome infection when gene expression was examined using blood, liver, lymph node, and spleen samples with peaks and troughs of gene expression differences following the cyclic pattern of parasitaemia exhibited during trypanosome infection. However, differences in response to infection between the two breeds were reflected in differential expression of genes related to the immune system such as those encoding antimicrobial peptides and cytokines, including, for example, the antimicrobial peptide encoding genes LEAP2, CATHL3, DEFB4A, and S100A7 and the cytokine genes CCL20, CXCL11, CXCL13, CXCL16, CXCL17, IL33, and TNFSF13B. In addition, transcriptional profiling of peripheral blood identified expression differences in genes relating to coagulation and iron homeostasis, which supports the hypothesis that the dual control of parasitaemia and the anaemia resulting from the innate immune response to trypanosome parasites is key to trypanotolerance and provide new insights into the molecular mechanisms underlying this phenomenon.

Animals↗

PubMed2025

Marine-Inspired Antimicrobial Peptides Disrupt Gene Expression at the DNA Level.

Genome mining of Streptomyces sp. H-KF8 combined with sequence engineering yielded two serum-stable, noncytotoxic, nonlytic antimicrobial peptides, L3 and L3-K. Initial studies in uropathogenic Escherichia coli suggested membrane effects and nucleoid relaxation, prompting a comprehensive investigation of their mode of action. In this study tandem mass tag (TMT)-based quantitative proteomics revealed extensive proteome remodeling, with 175 and 120 differentially expressed proteins (DEPs) after treatment with L3 and L3-K, respectively. L3 induced predominantly upregulated responses linked to metabolism, RNA processing, transport, and homeostasis, whereas L3-K mainly caused the downregulation of proteins involved in metabolism, transport, and cell structure. Both peptides disrupted ABC transporter-mediated nutrient uptake and elicited stress responses, while L3 specifically perturbed the mal regulon, indicative of broader transcriptional dysregulation. Complementary fluorescent dye displacement and in vitro transcription/translation assays demonstrated nonspecific DNA binding, stronger for L3 than L3-K, and potent inhibition of transcriptional and translational processes. Strikingly, inhibitory concentrations paralleled their minimum inhibitory concentrations, directly linking DNA binding and interference with central information processing to antimicrobial activity. These findings reveal that L3 and L3-K primarily act by targeting DNA and interfering with the transcription-translation machinery. Beyond offering mechanistic insights, this study underscores peptides' potential to act as scaffolds for next-generation antimicrobial peptides with DNA-binding and nonmembrane-lytic activity.

Antimicrobial Peptides↗

PubMed2019

Distinct types of short open reading frames are translated in plant cells.

Genomes contain millions of short (<100 codons) open reading frames (sORFs), which are usually dismissed during gene annotation. Nevertheless, peptides encoded by such sORFs can play important biological roles, and their impact on cellular processes has long been underestimated. Here, we analyzed approximately 70,000 transcribed sORFs in the model plant Physcomitrella patens (moss). Several distinct classes of sORFs that differ in terms of their position on transcripts and the level of evolutionary conservation are present in the moss genome. Over 5000 sORFs were conserved in at least one of 10 plant species examined. Mass spectrometry analysis of proteomic and peptidomic data sets suggested that tens of sORFs located on distinct parts of mRNAs and long noncoding RNAs (lncRNAs) are translated, including conserved sORFs. Translational analysis of the sORFs and main ORFs at a single locus suggested the existence of genes that code for multiple proteins and peptides with tissue-specific expression. Functional analysis of four lncRNA-encoded peptides showed that sORFs-encoded peptides are involved in regulation of growth and differentiation in moss. Knocking out lncRNA-encoded peptides resulted in a decrease of moss growth. In contrast, the overexpression of these peptides resulted in a diverse range of phenotypic effects. Our results thus open new avenues for discovering novel, biologically active peptides in the plant kingdom.

Bryopsida↗

PubMed2025

PhIP-Seq uncovers marked heterogeneity in acute rheumatic fever autoantibodies.

Acute rheumatic fever (ARF) and associated rheumatic heart disease are serious sequelae after infection with group A Streptococcus (Strep A). Autoantibodies are thought to contribute to pathogenesis, with deeper exploration of the autoantibody repertoire needed to improve mechanistic understanding and identify new biomarkers. Phage immunoprecipitation sequencing (PhIP-Seq) with the HuScan library (>250,000 overlapping 90-mer peptides spanning the human proteome) was utilized to analyze autoreactivity in sera from children with ARF, uncomplicated Strep A pharyngitis, and matched healthy controls. A global proteome-wide increase in autoantigen reactivity was observed in ARF, as was marked heterogeneity between patients. Public epitopes, common between individuals with ARF were rare, and comprised less than 1% of all enriched peptides. Differential analysis identified both unknown and previously identified ARF autoantigens, including PPP1R12B, a myosin phosphatase complex regulatory subunit expressed in cardiac muscle, and members of the collagen protein family, respectively. Pathway analysis found antigens from the disease-relevant processes encompassing sarcomere and heart morphogenesis were targeted. In sum, PhIP-Seq has substantially expanded the spectrum of autoantigens in ARF, and reveals the rarity of public epitopes in the disease. It provides further support for the role of epitope spreading in pathogenesis and has identified PPP1R12B as an enriched autoantigen.

Humans↗

PubMed1976

Synthesis and secretion of secretory immunoglobulins: with special reference to dental diseases.

The distribution of immunoglobulin-containing cells in human tonsils, salivary glands, and inflamed gingiva is described. The cellular localization of J chain indicates that this peptide is a basic gene product of B cells that is expressed only in the early phase of clonal differentiation. Gland-associated immunocytes apparently are derived from this phase, which may be relevant to their local homing mechanism. The selective glandular transport of dimeric or polymeric IgA and 19S IgM may be determined by the content of J chain in these immunoglobulins. A J-chain-dependent configuration seems to be responsible for their noncovalent affinity for SC, and this may explain their specific reception at the epithelial cell membranes. Subsequent stabilization of the Ig-SC complexes takes place during their external transport, probably because of disulfide exchange. The latter process is more efficient for secretory IgA than for secretory IgM. The secretory dynamics of parotid IgA differs from that of other parotid proteins and is highly dependent on the degree of secretory stimulation. The secretion rate (mug/min/gland) seems to be a better measure of an individual's parotid IgA output than the absolute concentration of IgA in the secretion. A low parotid IgA secretion rate is associated with high susceptibility to dental caries, perhaps reflecting inferior resistance to dental plaque formation. It is not known whether such resistance, in part, is determined by specific antibodies to certain bacterial antigens. A potential candidate for an efficient preventive action of salivary antibodies could be the GTF enzyme system of S mutans. However, we were able to demonstrate only extremely rare immunocytes producing antibodies to GTF in human tonsils and gingiva, and none at all in salivary glands.

Antibodies, Bacterial↗

PubMed1979

Effects of a chromatin low molecular weight peptidic fraction on differentiation markers and virus production in Friend leukemia cells.

Low molecular weight chromatin peptides exert a dose-dependent inhibition of Dimethylsulfoxide (DMSO)-induced erythroid differentiation of murine Friend Leukemia Cells (FLC). This effect correlates with the degree of purification of the peptide fractions. Crot analysis of globin mRNA amounts in DMSO-treated FLC given the peptides showed a 4-5-fold decrease of messenger RNA in the cytoplasma with no nuclear storage of globin transcripts. Spectrin accumulation in "induced" FLC is inhibited as well. The effects of the peptides on erythroid markers are reversible upon removal of the compounds. They also appear to be specific for induced gene expression as (1) no effects are observed on cell growth and RNA synthesis in normal non-differentiating cell lines; and (2) no changes have been detected with regard to the expression of integrated viral genes coding for continuous shedding of viral particles.

Animals↗

PubMed1992

Effect of capsaicin and resiniferatoxin on peptidergic neurons in cultured dorsal root ganglion.

The neurotoxic effect of capsaicin has been shown to be selective on a subpopulation of small dorsal root ganglion neurons in newborn animals. The aim of this study was to provide evidence of the long lasting effect of capsaicin and its ultrapotent analog resiniferatoxin (RTX) on sensory peptidergic neurons maintained in organotypic cultures. The effects of the two irritants were examined on neurons that contained substance P (SP) and calcitonin gene-related peptide (CGRP). Exposure of the cultures to 10 microM capsaicin and 100 nM RTX for periods of 2 days or longer resulted in almost complete elimination of SP-immunoreactive (IR) neurites and reduction, but not elimination, of CGRP-IR neurites. In addition, both 10 microM capsaicin and 100 nM RTX significantly reduced the number of SP- and CGRP-IR cell bodies within DRG explants. Capsaicin in 100 microM concentration produced complete elimination of SP-IR fibers and a greater decrease in the number of CGRP-IR fibers, but failed to completely eliminate IR cell bodies. Exposure of the cultures to the irritants in the same concentrations for 90 min did not produce a measurable effect on SP- or CGRP-IR in neurites or cell bodies. It is important to establish that the effect of capsaicin and RTX on cultured neurons was of long duration (longer than 4 days) and is therefore different from depletion of peptides. These findings demonstrate that processes of cultured sensory neurons are much more sensitive to capsaicin and RTX than cell bodies. Furthermore, our results show that SP-IR neuronal elements are more sensitive to capsaicin than CGRP-IR elements. These data suggest that cultured sensory neurons express the functional properties of differentiated sensory neurons in vivo.

Animals↗

PubMed1992

The extracellular domain of the neurokinin-1 receptor is required for high-affinity binding of peptides.

The neurokinin-1 receptor binds neurokinin peptides with the potency order of substance P > substance K > neurokinin B. Elucidating the molecular basis of differential peptide selectivity will require the localization of the binding domain on the receptor. In the present report, mutagenesis and heterologous expression experiments reveal that a segment of the extracellular N-terminal sequence of the neurokinin-1 receptor is required for the high-affinity binding of substance P and related peptide agonists. Substitution of amino acid residues in the N-terminal region of the receptor affects the binding affinity of both intact peptides and a C-terminal substance P "analog", but not of a nonpeptide antagonist. Glycosylation of the receptor does not change the peptide binding affinity. In addition, substitution of the valine-97 residue in the rat neurokinin-1 receptor by a glutamate residue increases the binding affinity of neurokinin B but not substance P or substance K, suggesting that the second extracellular segment is involved in peptide selectivity. These results indicate that the extracellular domains of neurokinin-1 receptor play a critical role in peptide binding.

Amino Acid Sequence↗

PubMed1992

Increased expression of keratin polypeptides in long term culture of adult rat hepatocytes.

Adult rat hepatocyte cultures showed the presence of albumin after 1 week of seeding. As the cultures aged, the cells commenced expressing alpha-foetoprotein and later keratin polypeptides 55 and 52 kD but ceased expressing albumin and alpha-foetoprotein. Enhanced expression of keratin polypeptides was confirmed by Western blot analysis in long term cultures. A possible mechanism for dedifferentiation of hepatocytes in culture is discussed.

Albumins↗

PubMed2026

MDV-like endogenous viral elements act as immune rheostats in Aedes cells by modulating defensin A-mediated responses to arboviruses.

Mosquito cell lines are essential tools for arbovirus research. Endogenous viral elements (EVEs) are prevalent in mosquito genomes, yet their functional effects on host immune responses remain unclear, potentially complicating experimental interpretations. In this study, we systematically characterized endogenous mosquito densovirus-like elements (EMLs) within the Aedes aegypti Aag2 cell line and found that these endogenous EMLs are transcriptionally active but translationally defective. The silencing of EML transcripts significantly diminished the replication of Zika virus (ZIKV), Japanese encephalitis virus (JEV), and chikungunya virus (CHIKV), while transiently increasing dengue virus 2 (DENV-2), thereby indicating a virus-dependent regulatory mechanism. Mechanistically, RNA sequencing after EML interference, alongside plasmid-based mimic expression, demonstrated that EML transcripts downregulate defensin A, an antimicrobial peptide produced by mosquitoes. Functional assays using synthetic defensin A showed that this peptide differentially regulates arboviral infection. Binding assays and structural modeling further supported its interaction with viral envelope proteins, while stage-restricted infection assays revealed distinct stages of action: defensin A enhanced adsorption of ZIKV, JEV, and CHIKV, but did not promote DENV-2 adsorption or entry, and instead reduced DENV-2 RNA accumulation at the post-entry replication stage. Our findings highlight a previously unrecognized role of densovirus-derived EVEs in mosquito innate immunity, extending their functional scope from the well-established PIWI-interacting RNA-mediated antiviral defense to the regulation of antimicrobial peptide-associated immune pathways. These findings emphasize the necessity of accounting for EVE activity when analyzing data derived from mosquito cell lines, and suggest that related EVE-mediated immune regulation may contribute to arbovirus dynamics in mosquitoes.IMPORTANCEMosquito-borne viruses such as dengue, Zika, Japanese encephalitis, and chikungunya continue to threaten human health worldwide. Laboratory studies often use Aedes aegypti cell lines to investigate how these viruses interact with their mosquito hosts. Here, we show that the genomes of these cells contain endogenous viral elements derived from mosquito densoviruses. Far from being inert fossils, these sequences are transcriptionally active and regulate mosquito immunity by suppressing the antimicrobial peptide defensin A. This immune modulation influences the replication of different arboviruses in opposite ways, enhancing some while restricting others. Our findings reveal that integrated viral elements can shape the outcome of arbovirus infection, with important implications for interpreting mosquito cell culture experiments and for evaluating endogenous viral element-mediated immune regulation in mosquito-virus interactions.

Aag2 cell↗

PubMed2025

Proteomic profiling identifies miR-423-5p as a modulator of oncogenic metabolism in HCC.

BACKGROUND: Hepatocellular carcinoma (HCC) remains a significant clinical challenge due to limited diagnostic and therapeutic options. Non-coding RNAs (ncRNAs), such as microRNAs (miRNAs), play key roles in cancer biology. Our previous findings showed that miR-423-5p enhances anti-cancer effects on HCC patients treated with sorafenib by promoting autophagy. Here, we investigated the molecular mechanisms underlying miR-423-5p function through a comprehensive proteomic approach. METHODS: We generated an HCC cell line stably overexpressing miR-423-5p via lentiviral transduction. Total proteins were extracted from SNU-387 cells, enzymatically digested into peptides, and subsequently analysed by liquid chromatography-tandem mass spectrometry (LC-MS/M). Raw spectral data were processed and quantified using MaxQuant. Differentially expressed proteins (DEPs) were defined based on fold-change (|log2FC| ≥ 1) and false discovery rate (FDR < 0.05). The full proteomic dataset is available via the ProteomeXchange repository (identifier: PXD064869). Functional enrichment analysis of DEPs were performed using DAVID and Reactome. To assess clinical relevance, predicted and validated miR-423-5p targets were integrated with The Cancer Genome Atlas (TCGA) Liver Hepatocellular Carcinoma (LIHC) dataset using GEPIA platform. Survival analyses were performed using the Kaplan-Meier method. RESULTS: Proteomic profiling identified 698 DEPs in miR-423-5p-overexpressing cells compared to controls with significant enrichment in metabolic pathways, related to purine/pyrimidine metabolism and gluconeogenesis. Integration with bioinformatic predictions and miRTarBase validation identified 43 DEPs as potential direct targets of miR-423-5p. Among these, seven proteins (ACACA, ANKRD52, DVL3, MCM5, MCM7, RRM2, SPNS1, and SRM) were significantly associated with patient prognosis in the TCGA-LIHC cohort. These targets were downregulated in miR-423-5p-overexpressing cells but upregulated in advanced-stage HCC tissues, suggesting a potential role for miR-423-5p in the regulation of HCC pathogenesis. Stage-specific expression analysis showed increased levels from stage I to III, followed by a decline at stage IV. Notably, we experimentally confirmed miR-423-5p-mediated suppression of MCM7, DVL3, IMPDH1, and SRM (SPEE), supporting their functional involvement in HCC progression. CONCLUSION: Overall, our findings support a tumour-suppressive role for miR-423-5p in HCC, mediated by modulation of metabolic pathways and suppression of oncogenic proteins. These results suggest that miR-423-5p and its downstream effectors may serve as promising biomarkers and potential therapeutic targets in HCC. HIGHLIGHTS: miR-423-5p acts as a tumor suppressor in HCC by targeting key nodes of pro-tumorigenic signalling. miR-423-5p significantly altered metabolic pathways, including purine/pyrimidine metabolism and gluconeogenesis. Seven miR-423-5p targets correlate with poor prognosis in TCGA-LIHC patients and are downregulated in miR-423-5p overexpressing HCC cells. miR-423-5p over-expression induces a significant downregulation of MCM7, DVL3, IMPDH1, SPEE in HCC cell models. miR-423-5p limits tumor metabolic plasticity, suggesting therapeutic potential.

MicroRNAs↗