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Choi, Y.

Publications and source records attributed to Choi, Y..

At least 19 recordsLinked to original sources

Striatal M4 Receptors Mediate M4 PAM Antipsychotic-like Efficacy Independently of Normalizing Striatal Dopamine Release

Muscarinic acetylcholine receptor (mAChR) drugs have emerged as a promising new class of antipsychotics, highlighted by the FDA approval of Cobenfy, the first treatment for schizophrenia that does not directly target dopamine receptors. The M4 receptor subtype is thought to be a key mediator of antipsychotic-like efficacy. However, the in vivo circuit mechanisms underlying the antipsychotic-like efficacy observed with M4-selective positive allosteric modulators (PAMs) remain incompletely understood. Here, we used fiber photometry in awake, behaving mice to assess how the M4 PAM VU0467154 (VU'154) affects striatal dopamine (DA) transmission under basal and amphetamine-stimulated conditions. We also generated and validated dorsal striatum-specific M4 knockout mice (DS-M4-KO) to test the role of striatal M4 receptors in regulating DA release and antipsychotic-like effects. VU'154 dose-dependently reduced the amplitude of striatal DA release events under basal conditions without altering event frequency. However, VU'154 had no significant effects on tonic DA levels under basal conditions, as assessed using the D1 PAM DETQ. Despite robustly attenuating AHL, VU'154 produced little to no effect on amphetamine-induced DA levels, indicating that antipsychotic-like efficacy was dissociated from changes in striatal DA levels. Notably, VU'154 efficacy in AHL was absent in DS-M4-KO mice, demonstrating that M4 receptors in the dorsal striatum are required for antipsychotic-like effects. Combined with previous studies implicating a key role for M4 receptors on D1-expressing neurons, these findings suggest that M4 PAMs produce antipsychotic-like efficacy primarily through postsynaptic mechanisms in the dorsal striatum, rather than through broad normalization of amphetamine-induced DA release.

pharmacology and toxicology↗

Host brain infection induces RNAi epimutation in Mucor circinelloides and enhances blood-brain barrier invasion

Mucorales fungi cause mucormycosis, a rapidly progressive invasive fungal disease with high mortality, particularly in immunocompromised patients and in severe disseminated infections. Central nervous system involvement is among the most devastating manifestations of mucormycosis, yet the mechanisms that enable Mucorales to adapt to the brain environment remain poorly understood. In Mucor species, RNA interference (RNAi) can generate reversible heritable epimutations that silence specific genes without altering DNA sequence, providing a transient and reversible mechanism for antifungal drug resistance. Here, we show that host brain infection induces RNAi-dependent silencing of endogenous fungal loci that promote central nervous system adaptation. Small RNA sequencing of Mucor circinelloides recovered from infected mouse organs identified seven brain epimutation loci, named bepA to bepG, that accumulated small RNAs preferentially after brain infection. Among these, bepA encodes a conserved mitogen-activated protein kinase (MAPK)-like serine/threonine kinase related to cell wall integrity signaling. Deletion of the bepA gene confers resistance to the calcineurin inhibitors FK506 and cyclosporin A, allowing hyphal growth under conditions that impair calcineurin-dependent morphogenesis. BepA modulates FK506-induced MAPK signaling and controls a transcriptional program enriched in cell-wall remodeling genes. To model fungal central nervous system entry by a filamentous fungal pathogen, we established a human blood-brain barrier transwell platform that quantifies Mucor migration across brain endothelial monolayers. This model revealed that bepA mutation enhances fungal migration across brain endothelial monolayers without detectable changes in electrical barrier resistance. These findings identify brain-induced RNAi epimutation as a mechanism of organ-specific fungal adaptation and reveal reversible silencing of a MAPK-like kinase as a route to enhanced central nervous system invasion.

genetics↗

PREpiBind: Protein Representation-integrated Epitope--MHC Class II Binding Prediction

Accurate prediction of peptide-MHC class II (pMHC-II) binding remains challenging because of extensive MHC polymorphism and context-dependent peptide recognition, and it is unclear which protein representation best captures these determinants when the downstream model is held fixed. Here, we present PREpiBind, a pMHC-II prediction method based on a dual-stream, joint-attention framework that integrates MHC and epitope representations. We integrated ten protein representations spanning substitution-matrix, structure-prediction-derived, and protein language model (PLM) families and evaluated them under a common downstream architecture and identical splits across Qualitative, mass spectrometry (MS), and thresholded IC50 datasets. Overall, PREpiBind with PLM representations yielded higher performance than the evaluated reference methods in the Qualitative and MS datasets, whereas NetMHCIIpan-4.3 was higher on the thresholded IC50 datasets using its binding-affinity head. In pooled evaluations, PLM representations yielded the highest ROC-AUC values among the tested representations. ESM3 Large led the Qualitative dataset with an AUC value of 0.927 +/- 0.002, and PLMs also led on the MS and thresholded IC50 datasets. This advantage remained, but narrowed in allele-wise and leave-one-molecule-out evaluations, where structure-prediction-derived Chai-1 was competitive with the leading PLM representations. Under cross-species H2-out transfer, PLMs led when all H2 rows were pooled, whereas Chai-1 led when the eight H2 molecules were weighted equally. The small H2 panel did not support a stable ordering among these leading representations. The results indicate that protein representation choice should depend on the intended prediction scenario rather than on a single global ranking. PREpiBind is an openly available pMHC-II prediction framework with modular and flexible protein representations.

bioinformatics↗

An ancestral mitochondrial DNA insertion disrupts RNAi and enables persistence of a novel mycovirus in Cryptococcus neoformans

RNA interference (RNAi) is a widely conserved genome-defense mechanism that protects eukaryotes against viruses and transposable elements. We previously showed that RNAi loss can lead to hypermutation and antifungal drug resistance in the human fungal pathogen Cryptococcus neoformans, illuminating the potential clinical relevance of this pathway. In this study, we identified another function of RNAi in C. neoformans: mycovirus restriction. By screening known RNAi-deficient C. neoformans isolates, we identified a novel dsRNA mycovirus of the Orthototiviridae family, which we named CnTV1. We subsequently detected CnTV1 in three additional RNAi-deficient isolates. All CnTV1-positive isolates shared an ancestral nuclear mitochondrial DNA segment (NUMT) insertion that disrupts the gene encoding Argonaute (Ago1). Restoration of RNAi in sexually produced zygotes efficiently eliminated CnTV1. RNAi rescue by CRISPR-Cas9-mediated allele exchange eliminated CnTV1 during vegetative growth, further demonstrating RNAi is sufficient for mycoviral control. Loss of the RNA helicase Ski2 or the exoribonuclease Xrn1 increased CnTV1 abundance, revealing RNAi-independent restriction of the virus. Restoration of RNAi cleared the virus even in the absence of Ski2 or Xrn1, indicating a dominant role for RNAi in antiviral defense. To investigate the biological implications of CnTV1 infection, we developed a cytoplasmic-mixing approach and generated isogenic strain pairs in an RNAi-deficient background that differ only in viral infection status. Leveraging these strains, we show that CnTV1 infection leads to coordinated, low-magnitude transcriptomic changes and that strains lacking the mycovirus were moderately less virulent in a murine infection model. Our findings reveal that RNAi serves as a dominant antiviral defense system in C. neoformans and suggest that naturally occurring RNAi deficiency may be more prevalent than previously appreciated. This work highlights mycovirus persistence as an important consequence of RNAi loss in this WHO-designated critical priority fungal pathogen.

genetics↗

Structural proteomics reveals a coagulation-complement accessibility signature of macrovascular invasion in hepatocellular carcinoma

Macrovascular invasion (MVI) and extrahepatic spread (EHS) define the most aggressive, treatment-refractory hepatocellular carcinoma (HCC), yet blood-based markers that report the underlying protein-network biology are lacking. Conventional proteomics measures protein abundance but not the conformational and protein-protein-interaction (PPI) states that govern function. We applied covalent proteome painting (CPP)--a dimethylation-based accessibility assay that reads out binding-site openness--to matched tumor and serum, reasoning that intravascular tumor dissemination remodels plasma protein complexes in a manner detectable as changes in accessibility. Eight treatment-native HCC patients were profiled by CPP using matched FFPE tumor and top-14- depleted serum on a Q Exactive Orbitrap HF. The 85 tumor-serum common proteins defined an 81-protein targeted panel, validated by multiple-reaction-monitoring (MRM) mass spectrometry with heavy stable-isotope-standard peptides (296 peptides; 3,717 light/heavy transition pairs) in 22 FFPE tumors and 22 matched sera. Accessibility was the light/heavy ratio (high, open; low, closed). We assessed differential accessibility, serum-tissue translatability, pathway enrichment, and biomarker/survival performance. Aggressive disease showed broadly decreased protein accessibility. MVI-associated changes were directionally concordant between tumor and serum (Spearman {rho}=0.21; 59% concordant), driven by coagulation and complement proteins (FGG, CTSD, LBP, C4BPA); the EHS axis did not translate. Decreased-accessibility proteins were enriched for complement-coagulation cascades and IGF/IGFBP transport. A six-protein serum accessibility signature discriminated MVI (leave-one-out cross-validated AUC 0.80; best single markers ceruloplasmin 0.83 and haemoglobin- 0.77), and MVI status trended with shorter overall survival (log-rank p=0.06). Accessibility-based serum proteomics captures MVI-associated protein-complex remodeling that abundance assays miss, nominating a coagulation/complement-anchored serum signature for vascular-invasive HCC that warrants prospective validation.

systems biology↗

Hydrogel-enhanced bioelectrochemical nitrate reduction for ammonium recovery from dilute nitrate via Shewanella oneidensis MR-1

Bioelectrochemical reduction of dilute nitrate (NO-; sub-mM to low-mM range) to ammonium (NH) offers a promising route toward circular nitrogen management from contaminated groundwater and environmental waters. However, on-site application of bioelectrochemical systems remains challenging due to low reduction rates and poor electron transfer efficiency of naturally formed biofilm electrodes. Here, we constructed a hydrogel biocathode by applying a carbon black/riboflavin/sodium alginate/cellulose hydrogel incorporating Shewanella oneidensis MR-1 cells to a graphite felt electrode via brush coating. The hydrogel electrode achieved NH production rates of 0.16-0.19 mol m-3 h-{superscript 1} without NO2- accumulation, and these rates were maintained without significant performance loss across three consecutive cycles with medium exchange over 1.5 days of total operation. The hydrogel electrode increased the current density by more than 5-fold compared with a conventional S. oneidensis biofilm electrode, indicating enhanced electron transfer efficiency per unit biomass, which directly contributed to the high NH production rates. The electricity consumption for NH production of 1.68-2.39 x 10{superscript 2} kJ g-N-{superscript 1} was substantially lower than that of metal catalyst systems at comparable NO- concentrations (typically, >104 kJ g-N-{superscript 1}). These findings demonstrate that the hydrogel electrode design represents an energy-efficient, and readily fabricated platform for bioelectrochemical NH production from dilute NO-.

microbiology↗

A targeted plasma-proteomic axis separates autoimmune thyroid disease from growth-hormone deficiency

Targeted mass spectrometry (multiple-reaction monitoring, MRM) enables reproducible, multiplexed quantification of plasma proteins, but whether a fixed targeted panel can resolve endocrine disorders with overlapping systemic features is unknown. We analyzed a 256-protein targeted panel (1,894 peptides; 3,790 transitions) quantified in 57 participants spanning autoimmune thyroid disease (Hashimotos thyroiditis, n=7; Graves disease, n=5) and growth-hormone deficiency (GHD; partial, n=26; complete, n=19). Protein abundances were obtained by transition summation, log2 transformation, and per-sample median normalization. We applied unsupervised analysis (PCA, PERMANOVA), differential expression (limma), an ordered severity-trend test, and leave-one-out cross-validated classification with feature selection performed strictly inside each fold. All 256 proteins were quantified in every sample (median inter-sample r=0.875). PC1 (36% variance) separated autoimmune thyroid disease from GHD (p=0.016), whereas the global four-group structure was not significant (PERMANOVA p=0.17). No protein reached FDR<0.05, but the autoimmune-versus-GHD contrast was strongly enriched for low p-values (26 proteins at p<0.05; binomial p=5.4x10-4). The signal was biologically coherent: immunoglobulin/B-cell-receptor proteins, including CD79A, were lower, whereas proteasome subunits (PSMC5, PSMC3) and the NF-{kappa}B subunit RELA were higher in autoimmune disease. A cross-validated classifier separated the two classes (AUC 0.72; permutation p=0.05; eight proteins selected in all folds), whereas GHD severity was not predictable (AUC 0.31). A fixed 256-protein targeted panel reproducibly captures an immunoglobulin/B-cell-receptor and proteasome/NF-{kappa}B axis that distinguishes autoimmune thyroid disease from GHD but cannot resolve within-class severity.

systems biology↗

Sex and race shape serum protein biomarkers and bias diagnostic reference intervals

Clinical protein biomarkers--whether measured by FDA-cleared in-vitro diagnostic (IVD) assays or deployed as laboratory-developed tests (LDTs)--are routinely interpreted against fixed, population-agnostic reference intervals. Whether the baseline serum concentrations of these proteins differ systematically by sex and by self-reported race in healthy individuals has not been tested across a broad clinical panel on a single standardized platform. Using scheduled multiple reaction monitoring - mass spectrometry (MRM-MS) with stable-isotope-labelled internal standards, we quantified 87 proteins (39 FDA-cleared analytes; 48 LDT/research markers) in 60 healthy, age-matched donors balanced across three races (White, Hispanic, Black) and both sexes. Sex was a pervasive axis of variation: donors separated by sex in unsupervised multivariate space (PERMANOVA p = 0.020) but not by race (p = 0.14). Three FDA-target proteins differed by sex at FDR q < 0.05--sex hormone-binding globulin, haemoglobin- and albumin--with directions preserved within every race. Race differences were real but protein-specific, exemplified by ancestry-associated CD14. Critically, applying a single pooled 95% reference interval mis-flagged as many as [~]25% of a demographic subgroup as abnormal, versus the 5% expected. Demographic context should therefore be incorporated into reference intervals and decision thresholds for protein-based diagnostics.

molecular biology↗

A targeted mass-spectrometry plasma proteome for simultaneous multi-disease screening

Population health screening is fragmented across dozens of single-condition assays. We asked whether one targeted mass-spectrometry measurement of the plasma proteome could screen simultaneously for many common diseases. Using multiple-reaction-monitoring LC-MS/MS, we quantified 126 proteins (509 peptides) directly in crude plasma from 490 individuals spanning 16 diseases (eight cancers, three inflammatory or renal conditions, and five metabolic and lifestyle disorders) plus age- and sex-matched controls, each protein referenced to a stable-isotope-labelled internal standard. Proteome variation was organised primarily by disease rather than demographics. Cross-validated classifiers detected each disease against matched controls with a mean AUROC of 0.979, a 17-way model identified the specific disease at roughly ten times chance, and a 20-protein subset reproduced full-panel performance. We show that these within-cohort estimates are optimistic upper bounds because each disease was acquired as a separate case-control batch without independent validation. We quantify this, establishing analytical feasibility and defining the validation required for translation.

molecular biology↗

Age-dependent Structural Reorganization of the Human Plasma Proteome

Aging is characterized by progressive physiological decline, yet the molecular mechanisms underlying these changes remain incompletely understood. Although extensive work has examined age-related alterations in protein abundance, the age-dependent structural reorganization of proteins and their interaction networks remains largely unexplored. Here, we quantitatively characterize the structural dynamics of plasma proteins across healthy adult aging and identify age-dependent accessibility patterns that may serve as candidate structural biomarkers. We employed Covalent Protein Painting (CPP) coupled with multiple reaction monitoring (MRM)-based LC-MS/MS to analyze plasma from 24 healthy individuals spanning four age groups (20s to 50s, n = 6 per group). Lysine surface accessibility changes were analyzed using cosine similarity trajectory matching and limma-based linear modeling. The intersection of the two approaches defined five reproducible age-dependent trajectories encompassing 27 proteins and 57 peptides. Integrating STRING/Cytoscape network analysis with AlphaFold3 multimer complex prediction localized several CPP-detected peptides to within [~]5 [A] of predicted protein-protein interaction interfaces (KNG1, C3; REN, ALB; and ALB, FGB), suggesting that age-associated accessibility changes are organized at interaction interfaces rather than occurring as isolated local events. Our findings indicate that the human plasma proteome undergoes coordinated, network-level changes in structural accessibility during adult aging, providing a framework for structure-based biomarker discovery. Because CPP signal reflects both conformational accessibility and protein abundance, and because the cohort is modest and cross-sectional, the trajectories reported here are framed as hypothesis-generating and are interpreted with these constraints made explicit throughout.

molecular biology↗

AI-Informed neoantigen prioritization enables a multi-epitope mRNA/LNP vaccine with antigen-specific immunogenicity and antitumor activity

Personalized neoantigen vaccines are an emerging strategy for cancer immunotherapy, but their effectiveness depends on selecting tumor-specific antigens capable of inducing functional T-cell responses. The VACINUS AI-informed neoantigen prioritization framework previously identified and peptide-validated three immunogenic Tier 1 neoantigens in the B16F10 melanoma model. In this study, we extended that framework by translating these validated neoantigens into a multi-epitope messenger RNA vaccine formulated with lipid nanoparticles and evaluating its preclinical immunogenicity and antitumor activity. The three VACINUS-prioritized B16F10 neoantigens were encoded within a single multi-epitope construct, BF-V1_27-Ser, and formulated to generate BF-RNA-P. In B16F10 tumor-bearing mice, BF-RNA-P induced neoantigen-specific CD8+T-cell responses, with the strongest response directed against the B16F10-1-4 epitope. Combination with anti-PD-1 further enhanced vaccine-induced CD44+IFN-{gamma}+ CD8+ T-cell activation, whereas anti-PD-1 alone did not induce detectable peptide-specific responses. BF-RNA-P also suppressed tumor growth in vivo, and combination treatment produced the strongest antitumor effect, reflected by reduced tumor volume and lower endpoint tumor burden. Together, these findings demonstrate that VACINUS-prioritized and peptide-validated neoantigens can be reformatted into a multi-epitope messenger RNA/lipid nanoparticle vaccine while retaining antigen-specific immunogenicity and antitumor activity. This study provides preclinical proof-of-concept for integrating AI-informed, TCR-aware neoantigen prioritization with messenger RNA/lipid nanoparticle delivery as a translational strategy for personalized cancer vaccine development.

immunology↗

Methanogenic Ethanol Production from Acetate

Biological ethanol production is important for the circular carbon economy and makes up 73% of the U.S. biological fuels market. Previously, we produced ethanol by reversing methanogenesis and capturing methane by cloning methyl-coenzyme M reductase (Mcr) from an unculturable population of anaerobic methanotrophic archaea; this process was predicated on the generation of the intermediate acetate and its conversion by the methanogenic host to ethanol. Moreover, methanogens are generally thought to be detrimental for converting acetate to ethanol and are usually intentionally inhibited. Here, we demonstrate that direct growth on acetate as the sole carbon and energy source by the methanogen Methanosarcina acetivorans C2A results in 40% of the metabolized acetate becoming ethanol and that there is 430% more ethanol produced, compared to growth on methane via Mcr. In addition, we found growth on methanol results primarily in methane generation and low levels of ethanol. Therefore, acetate may be readily converted by the methanogen M. acetivorans to ethanol at high yields.

microbiology↗

HLiCA: An integrated cell atlas of the healthy human liver

The human liver is composed of a heterogeneous mix of cell types. How these distinct populations contribute individually and collectively to liver function remains poorly understood. Although single-cell technologies have advanced our understanding of liver biology, individual studies have often been limited by small donor cohorts and inconsistent cell type annotations. Integrating multiple datasets can overcome these challenges and better capture biological variability. We present the Human Liver Cell Atlas (HLiCA), an integrated reference of non-disease liver cells assembled from eight datasets across six research centers, encompassing more than 525,000 cells from 110 donors. Developed in collaboration with the Human Cell Atlas Liver Bionetwork, the HLiCA incorporates expert-curated cell annotations refined through community feedback and dedicated cell type annotation meetings. The HLiCA classifies cells into six lineages and expands the cell type resolution to include 47 distinct cell types. Starting from raw sequencing reads, we realigned all data and performed rigorous benchmarking to ensure robust integration across technical and biological variables. Genetic ancestry was inferred for all samples to evaluate the range of ancestral backgrounds represented in the atlas. The expanded cell type annotation enabled identification of previously unrecognized liver cell types, including NRXN1+ stromal cells. Their presence was validated using spatial transcriptomics, which localized NRXN1+ stromal cells to periportal regions. With the number of donors included in the HLiCA we were able to examine cell type specific associations with demographic covariates. In hepatocytes, drug metabolism genes showed differential expression between sexes, and in cholangiocytes, mucus-production genes varied with age. As the largest and most genetically diverse human liver cell atlas to date, the HLiCA provides a comprehensive, well-annotated reference for the field, annotated by expert consensus. This resource will enable deeper interrogation of liver cellular diversity, architecture, and function in the healthy human liver and serve as a reference to understand changes that occur with disease.

genomics↗

Spatial Transcriptomics Reveals a Conserved Border Niche and Etiology-Associated Immune Rewiring in Hepatocellular Carcinoma

Background and AimsThe tumor-stroma interface in hepatocellular carcinoma (HCC) harbors critical intercellular interactions that shape immune evasion and treatment response, yet its spatial architecture remains poorly characterized across etiologies. Whether hepatitis B virus (HBV)-related and non-B non-C (NBNC) HCC share conserved border niche features or exhibit etiology-specific microenvironment programs is unknown. We aimed to spatially resolve the tumor boundary ecosystem and identify etiology-associated signaling networks with translational relevance. Approach and ResultsWe performed 10x Visium spatial transcriptomics on 11 HCC specimens (7 HBV, 4 NBNC) and applied a machine-learning pipeline integrating CancerFinder and SpaceFlow to define tumor, boundary, and stromal domains. Across etiologies, the boundary zone showed a recurrent desmoplastic niche characterized by cancer-associated fibroblast, tumor-associated macrophage, and tumor endothelial cell accumulation with collagen-integrin extracellular matrix remodeling, including COL1A1-ITGA11 and COL4A1-ITGAV. Etiology-associated differences were observed in the organization of border-zone signaling programs. In representative HBV-related sections, CCL19-CCR7 signaling showed a comparatively restricted, endothelial-skewed topology, whereas representative NBNC sections showed broader inflammatory ligand-receptor networks with elevated NF-kB-associated pathway activity. ConclusionsThe HCC tumor-stroma border harbors a recurrent desmoplastic niche upon which etiology-associated immune regulatory programs may be superimposed. These findings generate spatial hypotheses relevant to etiology-informed biomarker development and future therapeutic stratification.

cancer biology↗

Telomere-to-telomere, accurate, and gapless genome assembly (TTAGGA) of the Korean Jindo dog with a single-contig Y chromosome

Complete canine reference genomes are essential for studies of structural variation, sex-chromosome evolution, and breed-specific architecture, yet existing references remain incomplete on the Y chromosome and retain internal gaps across multiple chromosomes. Here, we introduce TTAGGA (Telomere-to-Telomere, Accurate, Gapless Genome Assembly), a stricter completeness standard requiring chromosomes assembled end-to-end with zero internal gaps and Merqury consensus QV [&ge;] 50, and present Jindo1-G-TTAGGA, the first canine assembly to meet this standard, achieved under a stringent QV [&ge;] 60 threshold. From 813 Gb ([~]340x coverage) of multi-platform data (PacBio HiFi [~]150x, ONT ultra-long [~]103x, parental Illumina [~]40x per parent) generated from a male Korean Jindo dog, trio binning with hifiasm produced two haplotype-resolved assemblies of 2,441.6 Mb (Hap1, maternal, chrX-carrying) and 2,340.5 Mb (Hap2, paternal, chrY-carrying). Both haplotypes are gap-free at every internal position, with canonical telomeric repeats verified at both ends of all 39 chromosomes (tidk), Merqury consensus QV of 78.0 (Hap1) and 76.8 (Hap2), trio switch-error rates below 0.13%, BUSCO completeness of 99.3% (Hap1) and 96.4% (Hap2; the lower value reflects absent X-linked orthologues in the Y-bearing haplotype), and Genome Continuity Index values of 98.2 (Hap1) and 94.7 (Hap2). Hap2 carries a single 21,255,890 bp gap-free Y chromosome with TTAGGG telomeric repeats at the q-arm terminus and an acrocentric satellite-rich p-arm, representing a 5.4-fold increase over the 3.94 Mb chrY of ROS_Cfam_1.0 and adding approximately 14 Mb of newly resolved Y-linked sequence; this corresponds to roughly 79% of the cytogenetically estimated 27 Mb full-length canine chrY. Jindo1-G-TTAGGA provides a chromosome-scale, haplotype-resolved, gap-free canine reference for studies of canine structural variation, sex-chromosome evolution, and canid phylogenomics.

genomics↗

Systematic Profiling of Essential Fungal Transcription Factors Uncovers Ezt1 as a Central Pathobiological and Morphogenic Regulator in Cryptococcus neoformans

Cryptococcus neoformans is a global fungal pathogen that causes fatal cryptococcosis, and the limitations of current antifungals underscore the urgent need for new therapeutics. Here we systematically investigate essential transcriptional regulators in C. neoformans as potential antifungal targets, developing experimental pipelines that assess growth requirement, essentiality and function through conditional gene expression, constitutive overexpression, and meiotic spore analysis. We identify one quasi-essential (growth-required but non-essential) transcription factor, Fhl1, and 13 essential transcriptional regulators, three of which are transcription factors (Ezt1, Ezt2 and Cbf1) highly divergent from counterparts in other eukaryotes. Notably, Ezt1 modulates the expression of more than 1,200 genes, controlling growth, antifungal drug and stress responses, sexual development and virulence. Our findings define the essential transcriptional regulator landscape of C. neoformans and provide a framework for prioritising divergent essential regulators, particularly Ezt1, for antifungal target discovery.

microbiology↗

High-variance phenome database reveals important roles of WD40 proteins in the plant pathogenic fungus Fusarium graminearum

WD40 is a highly conserved protein domain in eukaryotes, playing a critical role in various cellular process. We conducted genome-wide functional analysis of WD40 genes in Fusarium graminearum-a phytopathogenic fungus that causes severe yield loss and mycotoxin contamination in major cereal crops. Comprehensive phenome analysis of 119 WD40 gene deletion mutants across 22 distinct phenotypic traits revealed phenotypic divergence within the phenome, establishing a strong correlation between virulence and sexual reproduction. Notably, 21 core WD40 genes were identified, offering valuable insights into divergent biological processes. Pilot interactome studies of Fgwd101 and Fgwd133 provided further insights into their potential pathobiological functions. Our investigation contributes to broadening our knowledge of the biological mechanisms underlying fungal pathogenesis and may assist in the identification of targets for antifungal agents.

molecular biology↗

Coordinated Tuning of Ionizable Lipids and Formulation Redirects mRNA Vaccines Toward Lymphoid-Specific CD4+ T Cell Immunity

The global success of mRNA vaccines has underscored the pivotal role of lipid nanoparticles (LNPs), yet how subtle chemical variations in ionizable lipids and their formulation parameters orchestrate complex immune landscapes remains largely elusive. Here, we report a novel ionizable lipid, N4Z, and demonstrate that its distinct chemical signature selectively intensifies early innate immune programs compared to its structural analogue, N4Y. Single-cell transcriptomic profiling at the injection site reveals that N4Z-based LNPs uniquely prime inflammatory and type I interferon-related transcriptional programs, accompanied by a rapid influx of B and CD4+ T cells. Beyond lipid chemistry, we show that formulation-level tuning, that is independent of the ionizable lipid structure, can reshape the systemic biodistribution from hepatic dominance toward lymphoid tissues. This optimization substantially enhances macrophage-associated antigen expression, which in turn amplifies polyfunctional CD4+ T cell responses, T follicular helper cell differentiation, and germinal center reactions. Our findings establish that the coordinated interplay between lipid engineering and formulation design provides a programmable platform for precision mRNA vaccination, achieving superior protective efficacy and neutralizing activity over clinically validated benchmarks.

bioengineering↗