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Biology subjects

Zhou, Q.

Publications and source records attributed to Zhou, Q..

At least 37 records · Page 2Linked to original sources

AlaRS-mediated lactylation shields PARP1 from ubiquitination to promote HNSCC progression

Abstract textMetabolic reprogramming in solid tumors causes massive lactate accumulation, yet how this drives oncogenesis remains incompletely understood. Here, we identify alanyl-tRNA synthetase (AlaRS) as a cellular lactyltransferase that promotes head and neck squamous cell carcinoma (HNSCC) progression. AlaRS directly catalyzes site-specific lactylation of the DNA repair protein PARP1 at lysines K249 and K667. Crucially, we uncover a competitive post-translational crosstalk wherein this lactylation directly antagonizes PARP1 ubiquitination. This "lactyl-shield" prevents proteasomal degradation, hyper-stabilizing the PARP1-Mortalin complex and sustaining tumor proliferation via p53/p21 dysregulation. To therapeutically exploit this mechanism, we identified chelerythrine (CHE) as a potent, selective inhibitor that directly binds the AlaRS catalytic center. CHE abrogates AlaRS lactyltransferase activity, destabilizes PARP1, and robustly suppresses HNSCC xenograft growth in vivo. These findings establish a novel metabolic-post-translational axis linking lactate accumulation to oncoprotein stabilization, providing a blueprint for targeting tRNA synthetase moonlighting functions in cancer.

molecular biology↗

Molecular basis for the role of Ripr in Plasmodium falciparum invasion of human erythrocytes

Plasmodium falciparum causes the majority of severe malaria, and merozoite invasion of erythrocytes is a vulnerable, antibody-accessible step of the blood-stage cycle. PfRipr is an essential component of the PCRCR invasion complex, yet the structural basis for antibody-mediated neutralisation remains unclear. Here, we map inhibitory and non-inhibitory epitopes across PfRipr and show that all potent inhibitors localise to the tail region (EGF6-8). Crystal structures reveal that inhibitory antibodies restrict the flexibility surrounding EGF7. Indeed, EGF7 buried surface area correlates strongly with inhibitory potency, identifying this domain as the principal invasion-inhibitory determinant. Pairwise antibody combinations revealed unexpected synergy, with non-inhibitory mAbs potentiating anti-Rh5 activity. Conditional deletion, sequence replacement or positional swapping of EGF6-8 abolished invasion, demonstrating that both sequence and spatial arrangement are indispensable. These data define EGF7 as a conserved, functionally essential vulnerability and provide a blueprint for rational EGF6-8 immunogen design capable of eliciting P. falciparum strain-transcending protection against blood-stage malaria.

biochemistry↗

FvTFL1 reverses the function of FvGI-FvCO-FvFT1 pathway in the photoperiodic flowering of woodland strawberry

O_LIPhotoperiod is a stable seasonal signal. Although the photoperiodic flowering is well understood in short-day (SD) and long-day (LD) annual plants, regulatory mechanisms in perennials remain elusive. In a perennial woodland strawberry (Fragaria vesca L.), flowering is induced in SDs in autumn and plants flower following spring, while in plants with mutated FvTERMINAL FLOWER1 (FvTFL1), LDs induce flowering. C_LIO_LIWe investigated photoperiodic flowering of F. vesca through phenotypic and molecular characterization of transgenic lines and their crosses. We studied natural variation in flowering time and gene expression in European accessions, and explored their correlations with climatic, geographical and genetic origins. C_LIO_LIWe showed that FvGIGANTEA (FvGI) and FvCONSTANS (FvCO) activate FvFLOWERING LOCUS T1 (FvFT1) in LDs resulting in early flowering in fvtfl1 mutant, while in SD F. vesca, activation of FvTFL1 by FvFT1 reverses the photoperiodic requirement of flowering. In natural accessions, decreasing expression of FvFT1 and FvTFL1 towards colder climates in the east and north correlated with earlier flowering. C_LIO_LIWe define a photoperiodic flowering mechanism controlling floral transition of perennial F. vesca in autumn that differs from known mechanisms in annual and perennial plants. Our findings open new avenues to understand how perennial plants cope with changing seasons across climatic and geographical ranges. C_LI

plant biology↗

A Divergent Class of Arylamine N-Acetyltransferases Catalyzes Convergent Amidative Condensation of Polyketides in Manumycins Biosynthesis

Polyketides are prized for their structural complexity and therapeutic potential, yet the incorporation of amide bonds into their frameworks typically relies on linear, nonribosomal peptide synthetase (NRPS)-dependent assembly. The direct, convergent coupling of distinct polyketide chains via amide bond formation--an ideal strategy for combinatorial biosynthesis--has remained largely elusive. Here, we report the discovery of a novel family of arylamine N-acetyltransferases (NATs) from manumycin-type biosynthetic pathways that catalyze an unprecedented intermolecular amidative chain transfer/condensation between an acyl carrier protein (ACP)-tethered polyketide donor and a free polyketide acceptor. Biochemical, structural, and molecular dynamics studies reveal that the representative enzyme, ColC2, possesses a distinctive substrate-binding pocket that diverges from canonical arylamine NATs, conferring exceptional promiscuity toward diverse acyl donors and acceptors. We demonstrate the utility of this biocatalyst by coupling arylamines with either synthetic acyl-thioesters or polyketide synthase (PKS) machinery to generate a library of non-natural polyketide amides and manumycin derivatives. These findings establish a new paradigm for amide bond formation in polyketide biosynthesis and position arylamine NATs as powerful tools for the development of novel therapeutics through combinatorial synthesis.

synthetic biology↗

KyDab - a comprehensive database of antibody discovery selection campaigns.

Preclinical antibody discovery relies on progressive screening and down-selection of candidate antibodies from large immune repertoires, yet this critical process is poorly represented in existing public databases. Here we introduce KyDab (Kymouse Antibody Database), a well-curated database of antibody discovery selection data generated using standardized workflows on the Kymouse humanized mouse platform. The current release includes 11 Kymouse platform mice immunisation studies covering 51 immunogens, more than 120,000 paired heavy-light chain sequences, and binding measurements for a selected subset of experimentally characterized clones. By capturing full-funnel selection data with consistent metadata and both positive and negative experimental outcomes, KyDab provides a valuable data resource for the development and evaluation of artificial intelligence models for antibody discovery. KyDab is accessible at https://kydab.naturalantibody.com/, and the database will be continuously updated as new datasets become available.

bioinformatics↗

When South meets North: a joint contact zone coinciding with environmental gradients in three boreal tree species

Post-glacial recolonization of Fennoscandia created secondary contact zones in many species, offering opportunities to study how gene flow and selection contribute to their establishment and maintenance. Here, we analyse genomic data from three boreal tree species--Picea abies, Betula pendula, and Pinus sylvestris--sampled along a latitudinal gradient in Sweden. Despite differences in colonization timing and dispersal ecology, all three species exhibit north-south genetic structuring aligned with environmental gradients. Most notably, the two main genetic clusters within each species overlap in a shared contact zone, corresponding to the climatic transition between Swedens two major environmental zones. The extent and structure of the contact zone differ among species: P. abies shows stronger genetic structure and moderate gene flow, B. pendula exhibits intermediate differentiation and gene flow, and P. sylvestris displays the weakest structure with stronger gene flow. All three species also show genomic signatures of local adaptation, with distinct underlying architectures. In P. abies, adaptive loci are broadly distributed across the genome, while, strikingly, they are mostly found within an inversion on chromosome 1 in B. pendula. In P. sylvestris, local adaptation likely relies on subtle allele frequency shifts across many loci with weak signals. These patterns align with theoretical expectations for polygenic local adaptation under varying migration regimes. Our comparative approach demonstrates how gene flow and selection jointly shape genomic landscapes in shared environments and contributes to understanding local adaptation in forest trees, with implications for predicting species responses to climate change.

evolutionary biology↗

In vivo-directed evolution identifies AAV-WM04 as a next-generation vector for potent and durable hearing restoration in DFNB9

Efficient and cell-specific gene delivery to cochlear inner hair cells (IHCs) remains a major challenge for inner ear gene therapy. Here, we identify and characterize a novel AAV2-derived capsid, AAV-WM04, that enables highly efficient and selective IHC transduction at low doses. Using an in vivo-directed evolution strategy, we generated a randomized AAV2 capsid library with 9-amino acid insertions and performed iterative selection in the adult mouse cochlea. Next-generation sequencing revealed enrichment of several variants, among which AAV-WM04 exhibited superior packaging efficiency and pronounced IHC tropism. AAV-WM04 achieved near-complete IHC transduction throughout the cochlear axis in adult mice, outperforming clinically relevant vectors with minimal off-target expression and no detectable ototoxicity. Robust and exclusive IHC transduction was further validated in non-human primates following round window membrane delivery, underscoring translational potential. Therapeutically, AAV-WM04 enabled efficient dual-AAV trans-splicing delivery of the large OTOF gene, resulting in uniform full-length otoferlin expression in IHCs. In a humanized Otof Q829X/Q829X mouse model, AAV-WM04 restored auditory function across a broad frequency range at relatively low doses and achieved durable hearing recovery. Collectively, these findings establish AAV-WM04 as a next-generation IHC-targeted vector with high efficiency, safety, and cross-species applicability for precision gene therapy of hereditary hearing loss.

genetics↗

Streak-Aware Localization Microscopy Enables High-Throughput Brain Imaging Across Platforms

Optical, ultrasound, and optoacoustic localization microscopy based on microparticle tracking has enabled surpassing the resolution limits imposed by ultrasound diffraction and optical diffusion in tissues. However, its reliance on high-speed (kilohertz) data acquisition systems for precise emitter localization and tracking substantially increases methodological complexity and data storage demands, limiting scalability and applicability beyond specialized benchtop platforms. Here, we present streak-aware localization microscopy (SALM) that employs localization- and tracking-free deep learning model to convert motion-blurred streaks originating from low frame rate recordings of flowing emitters into super-resolved structural and functional readouts. In optical implementations, SALM exploits streaks captured by low-speed cameras to recover capillary-level cerebrovascular maps across a variety of benchtop, miniaturized, and second near-infrared preclinical imaging platforms, achieving over 30-fold reduction in the reconstruction time compared to conventional localization pipelines. We further introduce three coded excitation strategies that embed finer time-varying vectorial flow signatures into individual streaks, enabling single-frame velocimetry and video-rate hemodynamic imaging. Extending SALM to ultrasound imaging enables high-fidelity vascular imaging with centimeter-scale penetration in rhesus macaque and rat brains while reducing plane-wave compounding frame rates by up to one order of magnitude. By overcoming long-standing trade-offs between spatiotemporal resolution and hardware complexity, SALM offers a flexible and scalable framework for next-generation super-resolution microscopy.

neuroscience↗

Myofibroblast lineage mapping and inhibiting subretinal fibrosis by targeting SMAD3 and MRTF pathways via microRNA-24 functional study

Subretinal fibrosis underlies the end-stage pathogenesis of retinal diseases including age-related macular degeneration (AMD). It can disrupt retinal structure and eventually lead to legal blindness by generating contractile force, fibrotic scarring, subretinal hemorrhage, and retinal detachment. Myofibroblasts are the predominant cells critically involved in subretinal fibrosis, however, the cellular contribution to myofibroblasts remains unclear. Here we demonstrate that multiple cell lineages, including macrophages, endothelial cells (EC), retinal pigment epithelial (RPE) cells and pericytes, significantly contribute to myofibroblasts in a laser-induced subretinal fibrosis model. We found microRNA miR-24 is significantly downregulated in the plasma of wet AMD patients. Overexpression of miR-24 represses epithelial-mesenchymal transition (EMT), endothelial-mesenchymal transition (EndMT), and the resulting fibrosis by regulating TGF-{beta}/SMAD3 and PAK4/LIMK2/MRTF pathways. Consistently, a combination of SMAD3 and MRTF inhibitors show superior efficacy to individual inhibitors in repressing fibrosis in vitro and laser-induced subretinal fibrosis in vivo. Together, these suggest the contribution of multiple cell-types in myofibroblast transformation in subretinal fibrosis, and repression of miR-24-regulated TGF-{beta}/SMAD3 and PAK4/LIMK2/MRTF pathways in multiple cell types holds therapeutic potential for treating subretinal fibrosis in AMD and other fibrotic disorders.

molecular biology↗

Event2Flow: Scalable imaging of peripheral and cerebral hemodynamics with event-based vision sensors

Accurate blood flow mapping over mesoscale fields of view is essential for understanding physiological and pathological processes, yet conventional optical methods often rely on bulky high-speed cameras that generate massive datasets with excessive computation burden. Here, we introduce Event2Flow, a compact and data-efficient framework leveraging event-based vision sensors, which asynchronously capture brightness changes with sub-millisecond latency and minimal data redundancy. Event2Flow supports multiple contrast mechanisms for flow measurement, including speckle fluctuation and particle tracking. By correlating the event count with flow velocity through simulations and experiments, we first demonstrate its application in laser speckle imaging for noninvasive mapping of mouse ear vasculature and ethanol-induced hemodynamic changes. When integrated with widefield fluorescence localization microscopy and point spread function engineering, Event2Flow further enables kilohertz-rate particle tracking for rapid 3D velocity quantification in transcranial brain imaging and snapshot flow direction estimations using event polarity. Overall, Event2Flow offers a scalable alternative to conventional high-speed imaging systems for vascular and neuroimaging applications.

neuroscience↗

Nonanticoagulated Heparin Derivatives Mediate Goblet Cell Differentiation to Restore the Mucosal Barrier for Ulcerative Colitis Therapy

Epithelial mucus barrier dysfunction is a pathological hallmark of ulcerative colitis (UC), yet current clinical therapeutic strategies primarily suppress inflammation, lacking reliable approaches for restoration of the mucosal layer. Here, through a systematic screen of our established library of deanticoagulated heparins, we identified NALHP, a non-anticoagulant low-molecular-weight heparin derivative, and its representative fraction S6 as orally active epithelial repair-promoting glycans. NALHP/S6 restored crypt architecture, mucus production and epithelial barrier integrity in experimental colitis. In UC patient-derived colonic organoids, NALHP/S6 reduced aberrant stem/proliferative programs while promoting secretory, absorptive and junctional maturation. Single-cell transcriptomics and temporal validation identified a transient repair-secretory transitional state (RSTS) positioned between classical Wnt-associated stemness and mature barrier-forming epithelial states. Transcriptomic analysis revealed coordinated attenuation of Wnt and Notch signaling, whereas pharmacological reactivation of these pathways opposed NALHP/S6-induced epithelial state progression. These findings define mucosal repair as a regulated epithelial-state transition and identify NALHP/S6 as glycan-based modulators capable of restoring this progression in UC epithelium.

pathology↗

Detection of Somatic Point Mutations Directly from Spatial Transcriptomics Enables in vivo Spatiotemporal Lineage Tracing

Spatial transcriptomics reveals tissue organization but lacks in vivo lineage-tracing methods applicable to humans. We introduce SpaceTracer, a computational framework that accurately detects somatic single-nucleotide variants (SNVs) directly from spatial transcriptomics data. By leveraging naturally occurring somatic SNVs, SpaceTracer reconstructs cellular phylogenies within native tissue architecture, enabling the mapping of lineage spread, migration, lineage-coupled expression changes and lineage-aware local interactions. Applied to human cutaneous squamous cell carcinoma, it traced tumor initiation and progressions, uncovered widespread pre-invasive migration of dedifferentiated epithelial cells and characterized mutant B cells migrating from tertiary lymphoid structures (TLS) into the tumor boundary. The framework also reconstructed developmental lineages across multiple tissues and identified tissue-resident mutant immune cells. SpaceTracer thus provides a perturbation-free platform for high-resolution spatiotemporal lineage tracing, offering a transformative tool for elucidating complex biological systems--especially tumor-immune ecosystems--with direct implications for advancing cancer immunotherapy.

bioinformatics↗

Neretva: Unsupervised Neural Variational Inference for Allele-level Genotyping of Highly Polymorphic Genes

Accurate genotyping and phasing of highly polymorphic gene families are essential for precision medicine. Yet, the genotyping problem remains computationally challenging due to extreme sequence similarity between related genes, copy number variation, and structural complexity. Current methods typically rely on integer linear programming or maximum likelihood-based approaches that often suffer from scalability and flexibility issues. Here, we present Neretva, a new framework that models the genotyping problem as a probabilistic latent variable model and employs auto-encoding variational Bayes (AEVB) for inference. Leveraging neural inference networks, our approach scales efficiently to complex gene families such as CYP (cytochrome P450) and KIR (killer-cell immunoglobulin-like receptors), and achieves competitive or improved accuracy over the current state of the art on both families. Neretva is open source and is freely available at https://github.com/0xTCG/neretva.

bioinformatics↗

Fully genetically encoded low-molecular-weight protein tags with defined shapes for direct molecular identification by cryo-electron tomography

Cryo-electron tomography (cryo-ET) enables three-dimensional visualization of cells in near-native states, but direct identification of specific proteins in situ remains challenging due to crowded cellular environments and the low intrinsic contrast of most proteins smaller than [~]500 kDa. Consequently, molecular identification often relies on indirect labeling strategies or bulky probes that can perturb native structures. Here we present a "shape-as-signal" strategy that uses fully genetically encoded protein tags with defined shapes as a molecular signal for direct identification by cryo-ET. We designed two single-chain, monomeric, low-molecular-weight tags: an extended V-shaped tag (62 kDa) and a compact triangular tag (85 kDa). Both adopt rigid geometries validated by cryo-electron microscopy and remain compatible with fluorescence microscopy when fused to fluorescent proteins. Their characteristic shapes are readily recognized and computationally detected in vitro. In cells, the V-shaped tag yields clear, non-disruptive signals at native locations. These results demonstrate that low-molecular-weight protein tags can be unambiguously detected and assigned in situ within crowded cellular environments. This single-step genetic tagging strategy enables seamless dual fluorescence and electron microscopy without exogenous probes, challenging the assumption that small protein tags are unsuitable for direct cryo-ET identification. More broadly, this approach establishes a scalable and minimally perturbative framework for visual proteomics and paves the way for multiplexed, shape-encoded molecular mapping in intact cells.

biophysics↗

Phosphorylation of KIN-G motor domain by Polo-like kinase negatively regulates centrin arm biogenesis in Trypanosoma brucei

The unicellular parasite Trypanosoma brucei assembles a motile flagellum that is required for locomotion, cell division plane placement, and cell-cell communication. Inheritance of the flagellum during the cell cycle relies on the faithful duplication/segregation of multiple flagellum-associated cytoskeletal structures, including a centrin-marked, bar-shaped structure termed centrin arm, which also determines the site for Golgi assembly. Biogenesis of the centrin arm requires the Polo-like kinase homolog TbPLK and the orphan kinesin KIN-G, but the mechanistic role of TbPLK in centrin arm biogenesis remains elusive. Here we report that TbPLK phosphorylates KIN-G, disrupts its microtubule-binding activity, and negatively regulates its function. TbPLK phosphorylates KIN-G in vitro at multiple residues, two of which are in vivo TbPLK phosphosites, including the Thr301 residue within one of the microtubule-binding motifs of the kinesin motor domain. Phosphorylation of Thr301 by TbPLK inhibits the microtubule-binding activity of KIN-G in vitro, and expression of a Thr301 phospho-mimic mutant in T. brucei disrupts centrin arm integrity, Golgi duplication, flagellum attachment zone elongation, flagellum positioning, and cell division plane placement. In wild-type T. brucei cells, Thr301 phosphorylation occurs on a small portion of the KIN-G population, suggesting that KIN-G undergoes phosphorylation/dephosphorylation cycles to regulate its activity. Together, these findings uncover a negative role of TbPLK-mediated phosphorylation of KIN-G in regulating centrin arm biogenesis in trypanosomes.

cell biology↗

Pial collaterals propagate neurovascular responses across functional units

Neurovascular coupling refers to the regulation of cerebral blood flow in response to neuronal activity, a process forming the basis for multiple functional neuroimaging techniques. However, the mechanisms that coordinate neurovascular responses across distinct cortical arterial territories remain poorly understood. Here we show that pial collaterals, arterio-arterial connections traditionally considered dormant under physiological conditions, serve as active conduits that propagate neurovascular signals between adjacent cortical territories and functional units. We demonstrate that neuronal activity in the somatosensory cortex triggers direct vascular signaling via endothelial Kir2.1 channels through pial collaterals, synchronizing blood flow responses beyond the activated area. The loss of pial collaterals abolished inter-territorial coupling without affecting local neurovascular responses. These results reveal that pial collaterals are critical regulators of cerebral perfusion.

neuroscience↗

Lignin degradation and valorization by Pseudomonas putida KT2440: a new role for glutathione peroxidase

Lignin, a complex natural aromatic polymer, poses significant challenges to its efficient degradation, hindering the utilization of biomass for many industrial applications. Bacterial degradation of lignin may offer a promising solution to this challenge. This project aimed at elucidating the function of secreted oxidative enzymes from Pseudomonas putida involved in lignin degradation and utilization. Using CRISPR-Cas9 and CRISPR-Cas3 systems, the putative lignin-degrading versatile peroxidase gene (VP; PP_1686, originally annotated as glutathione peroxidase GPx) and dye-decolorizing peroxidase gene (PP_3248) were individually knocked out from P. putida KT2440. The {Delta}PP_1686 mutant exhibited impaired growth and utilization of lignin-derived compounds. This correlated with reduced expression of p-hydroxybenzoate hydroxylase pobA and of DNA repair modules, alongside compensatory upregulation of energy and redox supply pathways. This work expands our knowledge on bacterial glutathione peroxidase by presenting a role beyond ROS scavenging. This work revealed the importance of P. putida VP/GPx in maintaining redox balance while supporting lignin-derived aromatic metabolism, offering new targets for future investigation into stress-metabolism crosstalk and lignin valorization strategies.

microbiology↗