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Zhao, Y.

Publications and source records attributed to Zhao, Y..

At least 145 records · Page 8Linked to original sources

DeSCENT: Deconvolutional Single-Cell RNA-seq Enhances Transcriptome-based Cancer Survival Analysis

MotivationAccurate cancer survival prediction requires modeling tumor heterogeneity across both population and cell levels. Most cancer survival analyses use tumor transcriptomes only, since cohorts are usually measured with bulk RNA-seq but are rarely recorded with single-cell RNA-seq. This prevents the direct use of cell-level transcriptomes in cancer survival analysis. ResultsTo bridge this gap, we propose using bulk RNA-seq deconvolution algorithms to reconstruct each subjects scRNA-seq profile from their bulk data. Then, by combining both scRNA-seq and bulk RNA-seq together with their survival labels (paired to bulk), we perform multimodal transcriptome-based survival analysis. We built this framework as DeSCENT and evaluated it with common survival models on eight TCGA cancer cohorts. Results showed notable and consistent improvements in C-index over bulk-only models or models using cellular information alone. AvailabilityOur code is available at GitHub: https://github.com/YonghaoZhao722/DeSCENT. Contactzpluo@swjtu.edu.cn; y.he@imperial.ac.uk Supplementary informationSupplementary data are available at Bioinformatics online.

bioinformatics↗

Improved vector toolkit for genome writing in mammalian cells

Efficient genome writing in mammalian cells requires robust methods for integrating large DNA payloads. The previously described method mammalian Switching Antibiotic resistance markers Progressively for Integration (mSwAP-In) enables iterative, biallelic genome rewriting in mammalian stem cells with DNA payloads exceeding 100 kb. However, the lack of standardized vectors and certain technical constraints have limited its broader adoption. Here we present an improved plasmid toolkit designed to streamline the implementation of mSwAP-In. The toolkit includes two core vectors. pLP-TK (pCTC174) is a landing-pad plasmid compatible with Golden Gate assembly of genomic homology arms and supports both mSwAP-In and the recombinase-mediated cassette exchange method Big-IN. mSwAP-In MC2v2 (pKBA135) is a versatile Big DNA assembly and delivery vector that supports Gibson-based assembly and incorporates positive, negative, and fluorescent selection markers, as well as a backbone counterselection cassette to minimize unwanted plasmid integration. The vector architecture also enables propagation in yeast and bacterial hosts, inducible plasmid copy-number amplification in standard E. coli strains, and CRISPR/Cas9-mediated payload release through preinstalled guide RNA target sites. We further characterize the FCU1/5-FC counterselection system in mouse embryonic stem cells and define conditions that minimize its bystander toxicity. Finally, we provide a set of Cas9-gRNA expression plasmids optimized for common mSwAP-In applications. Together, these reagents constitute a standardized and experimentally validated toolkit that simplifies large-scale genome writing using mSwAP-In.

synthetic biology↗

Development of a BM7G((TKO/hCD46/hCD55/hTHBD/hEPCR) Donor Pig with Endogenous Promoter-Driven Transgenes for Xenotransplantation

Xenotransplantation offers a potential solution to the organ shortage crisis. Multi-gene modification of pigs, such as knockout of three carbohydrate antigen-related genes and expression of immunoprotective proteins, can significantly improve xenograft survival. However, existing strategies face challenges: transposon-based transgenesis may lead to unstable expression, while exogenous promoters used in site-specific integration are susceptible to epigenetic silencing, hindering long-term stable expression. Therefore, developing a donor pig model capable of sustained multi-gene expression is critical. To address this, CRISPR-Cas9 was used to knockout three major glycan antigen genes to eliminate hyperacute rejection. Subsequently, four human protective genes were site-specifically integrated into the porcine Rosa26 safe-harbor locus, with expression driven by the endogenous Rosa26 promoter and the THBD core promoter for long-term stable and tissue-specific expression, and the selection marker was removed using Cre/loxP. Results showed complete absence of the three glycan antigens in BM7G pigs, while the four protective proteins were stably expressed in vascular endothelial cells and major organs. Among them, hCD55 and hCD46 were widely expressed, while hTHBD and hEPCR showed vascular-specific expression. In-vitro assays confirmed that BM7G porcine endothelial cells significantly reduced human antibody binding, effectively inhibited complement-dependent cytotoxicity, and decreased thrombin-antithrombin complex formation. In conclusion, by combining xenoantigen knockout with endogenous promoter-driven expression of multiple human protective genes, a seven-gene modified pig model with low immunogenicity and synergistic protective function was successfully constructed, providing an important donor resource for xenotransplantation preclinical research.

immunology↗

Mutation of eat-2 in C. elegans is not a reliable model for dietary restriction studies

Dietary restriction (DR) extends lifespan in many animal species. In C. elegans, Eat mutants with pharyngeal defects that impair feeding exhibit reduced growth rate and fertility and are typically long-lived, suggesting a DR effect. We report that Eat mutant longevity is largely or wholly a consequence of suppression of feeding activity-dependent infection of the pharynx by their E. coli food source. eat-2 mutants, widely used as a DR model, were among only 2/8 Eat mutants tested whose longevity were to any degree independent of bacterial infection. Moreover, among Eat mutants, phenotypic indicators of reduced nutrition correlated with one another, yet not with longevity. These findings document how, if infection is excluded, Eat mutants experience reduced nutrition, but in most cases not longevity, i.e. life-extending DR effects are not typical of Eat mutants. Thus, eat-2 longevity is partially due to infection resistance rather than DR, and residual, pharyngeal infection-independent longevity (contributing [~]40% of the total increase in lifespan) could reflect DR, or alternatively some other consequence of their nicotinic acetylcholine receptor defect.

physiology↗

STING agonist-mediated endothelial cell activation drives NK cells and neutrophils-dependent pulmonary inflammation

Stimulator of interferon genes (STING) agonists and derivative molecules have been extensively developed for tumor immunotherapy. However, systemic exposure toxicity risks have constrained clinical trial progression and even threatened patient lives. Currently, systematic toxicity assessments for STING agonists remain lacking, with the mode of action for major organ injury yet to be elucidated. Here, we focused on STING agonist-induced lung injury, revealing that systemic administration of STING agonists caused pulmonary hemorrhage, inflammatory alterations, and respiratory dysfunction. Through single-cell RNA sequencing and immune deletion studies, we found that lung endothelial cells could be stimulated by STING agonists and then secreted chemokines and IL-15 to recruit and activate NK cells. NK cells could induce endothelial cell apoptosis via IFN-{gamma}. Tbx21+ NK subpopulations, which activated by endothelial cells, could produce chemokines to recruit neutrophils. Neutrophils secreted IL-1{beta} through positive feedback pathways and form neutrophil extracellular traps during lung injury. This study elucidates the critical role of the endothelial cell-NK cell-neutrophil axis in mediating STING agonist-associated pneumonia, offering insights for developing intervention strategies for STING agonist toxicity.

pharmacology and toxicology↗

Molecular Glue-Induced Homodimerization Drives Targeted CRBN Autodegradation

Molecular glue degraders (MGDs) offer a sophisticated, proximity-based approach to protein modulation. In this study, we introduce LJY-3-60, a novel proximity-inducing agent that unexpectedly triggers the potent and selective autodegradation of CRBN. Evidence from CRISPR-Cas9 screening and IP-MS reveals that this degradation process is strictly governed by the intrinsic CRL4CRBN machinery, independent of any extrinsic E3 recruitment. Through a combination of cellular and biophysical characterizations, we demonstrate that LJY-3-60 acts as a molecular bridge to template CRBN homodimerization. This mechanism is unequivocally elucidated by the atomic-resolution co-crystal structure of the CRBNMidi-LJY-3-60 complex. The structure explicitly delineates the homodimerization interface, revealing how the ligand reorganizes the protein surface to stabilize a non-canonical architecture that drives trans-autoubiquitination and subsequent proteasomal degradation. Furthermore, LJY-3-60 serves as a highly effective, controllable off-switch to mitigate PROTAC-induced toxicity. Ultimately, this work delivers a robust chemical tool for modulating CRBN stability. By demonstrating how a small molecule can functionally mimic an endogenous E3 substrates degron to catalyse targeted autodegradation, this study establishes a rational structural framework for designing the next generation of self-destructive modulators in targeted protein degradation (TPD) therapeutics.

biochemistry↗

Circadian Dysregulation in Aging Alters Senescence and Inflammatory Pathways in a Sex- and Time-of-Day Dependent Manner

The circadian rhythm orchestrates gene expression and critical physiological processes but becomes disrupted with aging, contributing to disease. How this disruption interacts with cellular senescence--a key driver of aging pathology--remains poorly defined. We studied renal gene expression at four timepoints over 24hrs in 6- and 24-month-old genetically diverse UM-HET3 mice of both sexes and performed complementary analyses in synchronized fibroblasts sampled at seven timepoints. Aging dysregulated core clock relationships, including loss of the canonical anti-phase expression between Bmal1 and Per2. Senescence-associated genes were not static but exhibited pronounced oscillations, with senescence phenotypes varying by sex and time of day. Differential expression analysis revealed immune activation, metabolic rewiring, and epigenetic changes that were sex- and time-dependent. Variance analysis uncovered increased transcriptional noise in aging, particularly in circadian-regulated pathways such as RNA splicing, ribosome biogenesis, and TOR signaling. Single-nucleus RNA-Seq identified two cell populations lacking the normal Bmal1-Cdkn1a expression relationship: one senescent-like and another profibrotic, revealing distinct cell states linked to circadian dysregulation. Fibroblasts recapitulated key age-related circadian changes seen in the kidneys, including phase shifts in mTOR and oxidative phosphorylation. Together, this work demonstrates that senescence phenotypes are dynamic, sex-specific, and time-of-day dependent, and introduces a new framework for detecting senescent cells based on circadian gene relationships. These findings underscore the need to integrate temporal context into aging research and therapeutic strategies. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=185 HEIGHT=200 SRC="FIGDIR/small/709919v1_ufig1.gif" ALT="Figure 1"> View larger version (86K): org.highwire.dtl.DTLVardef@247e70org.highwire.dtl.DTLVardef@1e8f66borg.highwire.dtl.DTLVardef@18a0673org.highwire.dtl.DTLVardef@ad91d7_HPS_FORMAT_FIGEXP M_FIG C_FIG

genetics↗

A bacterial effector blocks SUMOylation by steric occlusion of UBC9 via arginine-GlcNAcylation

The post-translational modifier SUMO is crucial for host antimicrobial defense. Here, we discover that Salmonella employs a unique strategy to dismantle the host SUMOylation machinery. Salmonella infection robustly inhibits global SUMOylation, particularly SUMO2/3 conjugation, without altering the expression of SUMO-cycle enzymes. Genetic screening identified the T3SS-2 effector SseK1 as both necessary and sufficient for this suppression. SseK1, an arginine-GlcNAcyltransferase, directly binds and specifically modifies the SUMO E2-conjugating enzyme UBC9 at arginine 17 (R17). Structural and biophysical analyses revealed that GlcNAcylation at R17 sterically hinders UBC9s interaction with SUMO, thereby inactivating the entire SUMOylation cascade. A unique C-terminal lid domain (ARHVQ motif) in SseK1 confers substrate specificity for UBC9, representing an evolutionary innovation within Salmonella genus. Quantitative SUMOylome profiling demonstrated that SseK1-mediated UBC9 inactivation reprograms the host SUMOylation landscape, impairing the modification of key immune regulators such as MyD88, Hspa8 and destabilizing proteins like PDCD4. Consequently, this mechanism is critical for Salmonella intracellular survival and systemic virulence in mice. Our study unveils a unique bacterial strategy to dismantle the host SUMOylation machinery via precise enzymatic inactivation of its central hub.

biochemistry↗

Linking cross-species trajectories of cerebrovascular remodeling in aging and Alzheimer's disease to brain vessel transcriptome

Cerebrovascular remodeling driven by subtle molecular changes starts early in the asymptomatic stage of Alzheimers disease (AD). Despite progress in human vascular imaging and postmortem tissue analysis, there is limited data on the early features of small vessel reorganization, particularly in the context of cell-specific molecular drivers. This is largely because of the invasive nature of the tools for direct cellular observation and analysis. Since early detection is key, histopathology falls short with end-point data from people that died in late stages of the disease. This is a critical knowledge gap, because the early vascular processes are thought to be strongly correlated with health outcomes, tipping the scales from mild cognitive impairment to AD. To meet these translational challenges, we performed near life-span in vivo two-photon imaging and MRI of the cerebrovascular tree in a mouse model of amyloidosis. We identified precisely when subtle abnormalities in vessel tortuosity and red blood cell velocity first emerge in the context of differential amyloid accumulation in vessels walls and tissues. We then isolated the brain vessels for transcriptional analysis at this flagship timepoint and performed cross-species analysis linking changes in vascular cells to genes and pathways common to both mice and humans. Importantly, using 7T MRI of aging humans, we directly associated vascular remodeling trajectories of mice and humans and identified a remarkably analogous tortuosity course in the smallest brain vessels. Our integrated framework across scales and species advances neuroimaging biomarker understanding and uncovers early mechanistic routs of dysfunctional angiogenesis and actin-mediated contractility.

neuroscience↗

Genome-wide maps of transcription factor footprints identify noncoding variants rewiring gene regulatory networks with varTFBridge

Genome-wide association studies have identified millions of noncoding loci linked to human traits, yet how these variants alter gene regulation remains a major challenge, particularly for rare variants where whole-genome sequencing cohorts and high-resolution functional annotations remain limited. Here we show that single-molecule deaminase footprinting (FOODIE) in K562 cells captures up to 103-fold heritability enrichment for erythroid traits despite covering 0.12% of the genome. We introduce varTFBridge, integrating FOODIE footprinting with AlphaGenome variant effect prediction to identify causal noncoding variants altering transcription factor (TF)-mediated regulation. Applied to 490,640 UK Biobank genomes across 13 erythrocyte traits, varTFBridge prioritises 113 high-confidence regulatory variants (104 common, 9 rare), encompassing 2,173 linkages along the variant-TF binding- gene-trait cascade across 64 TFs and 108 genes. varTFBridge recapitulates rs112233623 and resolves its mechanism: GATA1/TAL1 co-binding disruption at a CCND3 enhancer altering red blood cell count and volume.

bioinformatics↗

Presymptomatic plant disease detection with PSNet: A low-cost hyperspectral imaging and RGB fusion framework.

Plant pathogens cause yield losses worldwide, threatening food security and livelihoods. Because early infection is difficult to diagnose, management often relies on prophylactic pesticide use, increasing costs and environmental impact. Here we present PSNet, a multimodal framework that fuses hyperspectral imaging with RGB information for presymptomatic plant disease detection, together with a low-cost hyperspectral camera incorporating a 3D-printed housing, costing under {pound}500. We validate PSNet using Arabidopsis thaliana infected with the oomycete Albugo candida. Imaging at 2 and 4 days post inoculation, prior to visible symptoms, revealed spectral signatures that distinguished infected from healthy plants, while imaging at 6 days post inoculation captured the transition toward early symptom emergence. Discriminative spectral regions overlapped wavelengths associated with plant responses to biotic stress, supporting the biological plausibility of these signatures. Performance was evaluated using strict plant-level partitioning, ensuring samples from the same plant were confined to a single split. On a four-class task (healthy, 2 dpi, 4 dpi, 6 dpi), PSNet achieved 90.00% accuracy and 97.50% accuracy for binary classification. Together, these results demonstrate that presymptomatic detection is feasible under controlled conditions using low-cost hardware and multimodal learning, underscoring the potential of scalable multimodal systems for early disease monitoring.

plant biology↗

Ligand-guided Sequence-structure Co-design of De Novo Functional Enzymes

Proteins underpin essential biological functions across all kingdoms of life. The capacity to design novel proteins with tailored activities holds transformative potential for biotechnology, medicine, and sustainability. However, since protein functions, particularly enzymatic activities, depend on precise interactions with small-molecule ligands, accurately modeling these interactions remains a formidable challenge in de novo protein design. Here, we introduce EnzyGen2, a protein foundation model designed for the simultaneous co-design of sequence and structure under ligand-guided functional targeting. Comprising 730 million parameters, EnzyGen2 is trained on 720,993 protein-ligand pairs using multi-task learning objectives that encompass joint prediction of sequence, structure, and protein-ligand interactions. In rigorous in silico benchmarks, EnzyGen2 consistently outperforms state-of-the-art baselines, including Inpainting, RFdiffusion/ProteinMPNN, RFdiffusion2/LigandMPNN, and RFdiffusion3/LigandMPNN, as measured by the enzyme-substrate prediction score, AlphaFold2 confidence metric, and structural fidelity, while it generates samples 400x faster than prior methods. We further experimentally validated EnzyGen2 across multiple enzyme families, including chloramphenicol acetyltransferase, aminoglycoside adenylyltransferase, and thiopurine S-methyltransferase. De novo enzymes generated by our family-specific EnzyGen2 exhibited catalytic activities comparable to or exceeding those of natural enzymes, while retaining substantial novelty with sequence identities as low as 51.6%. These results establish EnzyGen2 as a robust Artificial Intelligence-based tool for functional enzyme design, demonstrating the power of large protein foundation models to create high-performance, novel biocatalysts.

bioinformatics↗

Hierarchical Anchoring Gating Dictates Specific H4K16 Acetylation by the Human MSL Complex

Histone acetylation is a versatile post-translational modification essential for diverse biological processes. While nearly all histone acetyltransferases (HATs) act promiscuously on multiple lysine residues, the human male-specific lethal (MSL) acetyltransferase complex mediates strictly site-specific acetylation of histone H4 at lysine 16 (H4K16ac), with its underlying mechanism remaining enigmatic. Here, we leveraged chemical protein synthesis to engineer a semisynthetic nucleosome probe that traps the MSL complex in a catalytically engaged state and determined its 3.12 [A] cryo-electron microscopy (cryo-EM) structure, which reveals a hierarchical anchoring-gating mechanism responsible for stringent H4K16 selectivity. The MSL complex adopts a dual-anchoring mode to bind nucleosomal DNA at superhelix location (SHL) 1.5 and the H2A-H2B acidic patch. Three spatially coordinated gating elements (the MSL1 anchor helix, KAT8 gating helix, and KAT8 gating hairpin) then conformationally constrain the H4 N-terminal tail, funneling H4K16 side chain exclusively into the active site while sterically occluding flanking lysines. Targeted mutations disrupting these interfaces impair H4K16ac in vitro and in cells, with concomitant defects in chromatin accessibility and transcription. Beyond the monomeric 1:1 complex, cryo-EM analysis identifies a 2:2 MSL-nucleosome assembly, wherein MSL3 dimerization mediates inter-nucleosomal contacts linked to genome-wide H4K16ac patterning. Collectively, our work delineates a residue-to-domain framework in which a chromatin acetylation writer hardwires specific catalysis into nucleosome engagement and scales this precision to higher-order chromatin architecture, providing a mechanistic foothold for understanding aberrant MSL-encoded chromatin programs in diseases.

biochemistry↗

A mouse-adapted Yezo virus model for antiviral testing in immunocompetent mice

Emerging tick-borne orthonairoviruses pose a growing public health threat, yet few animal models fully recapitulate human disease. Here, we report the development of a mouse-adapted Yezo virus (MA-YEZV) strain that causes lethal infection in immunocompetent mice, mirroring key clinical features of human infection, including thrombocytopenia, leukopenia, and severe liver injury. Serial passaging of YEZV in C57BL/6J mice selected for 31 non-synonymous mutations, enhancing viral replication and pathogenicity. MA-YEZV exhibited broad tissue tropism, with the highest viral loads in the liver, and induced a robust inflammatory response marked by elevated proinflammatory cytokines (e.g., IFN-{gamma}, TNF-, IL-6) and inflammasome activation. Ribavirin treatment effectively suppressed viral replication, prevented mortality, and mitigated tissue damage, whereas remdesivir showed no efficacy. This model provides a critical tool for studying YEZV pathogenesis and antiviral development, while the identified mutations offer insights into viral adaptation and virulence mechanisms. Our findings underscore the potential of MA-YEZV as a platform for evaluating countermeasures against emerging orthonairoviruses.

microbiology↗

A foundation AI model enhances electron microscopy image analysis

Electron microscopy (EM) and advanced volume EM have extensive applications in deciphering cellular ultrastructures for life sciences. However, quality issues of EM images significantly impede the precise analysis and discovery of nanoscale biological structures. Here, we present an unsupervised Foundation Model for Five Tasks (DF5T) model for image enhancement through denoising, deblurring, super-resolution, two-dimensional (2D) inpainting, and three-dimensional (3D) isotropic restoration. DF5T was trained on an extensive dataset of multi-source membrane-bound organelle EM images, consisting of a total of over 2.25 million images. On unseen data, DF5T outperformed the existing state-of-the-art models in all five tasks. Furthermore, DF5T substantially compensates for missing three-dimensional structural information and reveals significant ultrastructural alterations in organelle geometry following chemical treatment. We demonstrate that DF5T significantly enhances electron microscopy images quality by improving the accuracy of downstream organelle segmentation and 3D structural restoration, thereby contributing to future advances in biological research.

cell biology↗

Nitro Reduction-Based RNA Control and Ultrafast Release

RNA protection and controlled release are critical for both fundamental research and therapeutic applications, yet the development of simple, efficient, and reversible post-synthetic RNA modification strategies remains a significant challenge. Here, we introduce a straight forward approach based on ribose 2'-hydroxyl acylation with a nitro-functionalized carbamate, which acts as a redox-responsive center. This modification selectively inhibits native RNA function while remaining inert to endogenous biogenic reductants and common reducing agents used in biological assays. Upon treatment with low millimolar concentrations of the THDB- BIPY reducing pair, RNA function is rapidly restored on a minute timescale. This methodology is broadly applicable across diverse RNA classes and functional contexts, including synthetic RNA oligomers, fluorogenic RNA aptamers, single-guide RNAs in CRISPR-Cas9 gene-editing systems, and mRNAs in living cells for translation control and RNAi-mediated gene silencing. These results demonstrate the general utility of this approach as a chemically controllable functional switch, providing a versatile toolkit for temporal regulation of RNA activity in both research and biotechnological applications.

biochemistry↗

The Bacteriocin Sublancin Restores Vancomycin efficacy against vancomycin-resistant enterococci in vitro and in vivo

Vancomycin-resistant enterococci (VRE) is one of the serious threat to global public health, with the diminishing effectiveness of antibiotics. There is an urgent need for novel strategies to control this multidrug-resistant bacterial infections. Here, our findings demonstrate that sublancin, a bacteriocin produced by Bacillus subtilis, exhibits intrinsic antibacterial activity and, more importantly, potentiates vancomycin, therapy restoring its efficacy against VRE. Using a series of in vitro assays, including fractional inhibitory concentration index, time-killing analysis, and resistance development assays, we show that sublancin significantly enhances the bactericidal effectiveness of vancomycin. In vivo, the sublancin-vancomycin combination therapy markedly reduced bacterial loads, improved svrvival rates in a Galleria mellonella model and enhanced bacterial clearance rates in a mouse model. Mechanistic studies using RT-PCR revealed that sublancin down-regulates the expression of the vanA resistance gene cluster. All in all, these findings make vancomycin and this antibiotic peptide combination as a promising candidatese to enhance vancomycin efficacy and overcome VRE infections, potentially through inteference with resistance gene expression.

pharmacology and toxicology↗

Non-canonical function of the splicing activator U2AF2 in promoting intron retention in the lncRNAs PURPL and MALAT1

Intron retention (IR) is increasingly recognized as a feature of long noncoding RNAs (lncRNAs), yet the mechanisms that shape IR in lncRNAs and the functional consequences of this process remain largely unexplored. To investigate how IR contributes to lncRNA regulation, we performed a genome-wide screen to identify factors controlling IR in the lncRNA PURPL. This approach uncovered a prominent role for U2AF2, which promotes retention of a specific intron in PURPL through a weak polypyrimidine tract. IR of this intron drives nuclear enrichment of PURPL and enhances cell proliferation, revealing biological relevance. Transcriptome-wide analyses showed that although U2AF2 broadly supports canonical splicing consistent with its well-established function in promoting splicing, it also facilitates IR within a distinct subset of RNAs, including the nuclear speckle-associated lncRNA MALAT1. Loss of U2AF2 disrupts MALAT1 speckle localization and using MALAT1 knockout cells reconstituted with wild-type or intron deleted variants, we identified a single intron critical for MALAT1s speckle localization. Deletion of this intron from endogenous MALAT1 impaired speckle localization and reduced cell migration, phenocopying the loss of MALAT1. Together, these findings reveal IR as a key regulatory mechanism governing lncRNA localization and function and uncover an unexpected role for U2AF2 in promoting IR within specific lncRNA contexts.

cell biology↗