Biology subjects

Cui, G.

Publications and source records attributed to Cui, G..

At least 19 recordsLinked to original sources

bioRxiv2026

Dopamine serves as an independent gain regulator to shape striatal control of movement

Dopamine (DA) drives locomotion by modulating striatal activity in the dorsolateral striatum (DLS). How DA regulates motor function on subsecond timescales remains poorly understood. To address this question, we performed spectrally resolved triple-color fiber photometry, allowing us to simultaneously monitor DA, glutamatergic inputs, and pathway-specific spiny projection neuron (SPN) activity in freely moving mice during spontaneous behaviors as measured by unsupervised behavior quantifications. We showed that DA dynamics were temporally distinct from spontaneous locomotor kinematics or behavioral states. Instead, peri-event DA levels predicted SPN input-output (I/O) efficacy, defined as SPN activity relative to glutamatergic input, with opposite relationships across pathways: higher DA predicted enhanced efficacy in direct-pathway SPNs but reduced efficacy in indirect-pathway SPNs. Paired with unsupervised behavior quantification, elevating extracellular DA with methylphenidate, a DA re-uptake inhibitor, shifted direct-pathway SPNs toward higher I/O gain and indirect-pathway SPNs toward lower neuronal activity outputs, while biasing behavior toward selected mobile and turning states. Reserpine administration, which mediates DA vesicular depletion, resulted in the opposite efficacy shifts and increased occupancy of immobile states. Together, these findings support that DA does not simply encode spontaneous movement, but acts as a pathway-specific gain controller that dynamically tunes the transformation of glutamatergic input into SPN output to bias locomotor-state transitions in vivo.

neuroscience↗

bioRxiv2026

Biosynthesis of bisbenzylisoquinoline alkaloids

Bisbenzylisoquinoline alkaloids (bisBIAs) are pharmacologically valuable plant metabolites with complex stereochemical architectures, yet the catalytic principles governing their assembly have remained largely unclear. Here, we elucidate the enzymatic pathway to cyclic bisBIAs and uncover a non-canonical redox-mediated mechanism for post-assembly stereochemical control. We identify cytochrome P450 enzymes that catalyze regioselective oxidative dimerization and macrocyclization of benzylisoquinoline monomers, establishing the macrocyclic scaffold. Subsequent stereochemical specification is achieved by a paired oxidase-reductase module that selectively epimerizes a single stereocenter through a transient imine formation, converting (R,S)-configured intermediates to (S,S)-products. Reconstitution of the pathway in yeast enabled production of both native bisBIAs and non-natural analogs, demonstrating pathway modularity and engineering potential. These results establish the biochemical principle underlying bisBIA biosynthesis and provide a framework for programmable biosynthesis of these complex natural products.

biochemistry↗

bioRxiv2026

Cell-type-specific transposable element transcription tracks symbiosis and calcification programs in the reef-building coral Acropora hemprichii

Transposable elements (TEs) are pervasive components of eukaryotic genomes and major drivers of genome evolution, yet their contribution to cell-type-specific regulatory landscapes remains poorly understood, particularly in non-model marine invertebrates. Here, we integrated single-cell RNA sequencing with pseudo-aligned TE expression profiling to examine how TE transcription relates to cell type identity in the reef-building coral Acropora hemprichii. We constructed a cell atlas comprising 4,716 cells across eight major cell types. Notably, TE expression alone was sufficient to accurately resolve all major cell types, indicating that cell-type-specific transcriptional states are robustly reflected in TE activity patterns. We identified 9,759 expressed TEs, of which 333 exhibited strong cell-type-specific activity. These differentially expressed TE features were associated with nearby expressed genes and transcription factor loci, suggesting a relationship between cell-type-specific TE activity and local gene regulatory programs. Genes associated with cell-type-specific TEs were enriched for core coral physiological processes, including calcification, metabolite transport, and symbiosis-related functions. Together, these findings indicate that TE transcription is structured along coral cell-type identity and physiological specialization. Our study provides a single-cell-resolved framework for investigating TE-gene relationships in early-diverging metazoans and a community resource for future functional interrogation in reef-building corals.

bioinformatics↗

bioRxiv2026

Membrane-resolved epithelial electrophysiology revealed using extracellular electrochemical impedance spectroscopy (EEIS)

Conventional extracellular epithelial electrophysiology measurements report only bulk transepithelial resistance and capacitance, obscuring the distinct electrical properties of the apical and basolateral membranes. This limitation hinders research of epithelial diseases where dysfunction originates at a specific membrane domain--apical or basolateral--for example in cystic fibrosis or toxin-mediated airway injury. Here we present the extracellular electrochemical impedance spectroscopy (EEIS) technique that extracts membrane-specific electrophysiology by fitting impedance spectra to a two-resistor, two-capacitor (RCRC) model. Using human bronchiolar epithelial monolayers (16HBE), we show a correlation between the electrical time constants of the circuit ({tau}1 = R1 {middle dot} C1,{tau} 2 = R2 {middle dot} C2) and changes in ion permeability of the basolateral and apical membranes. Experimentally, we show that blocking with 5-10 {micro}M GlyH-101 (i.e. decreasing apical membrane permeability), after 10 {micro}M forskolin activation elicits dose dependent{tau} 2 responses that are over 50% larger than{tau} 1and 6-7 minutes faster, whereas 10 {micro}M nystatin (i.e. increasing basolateral membrane permeability) produces{tau} 1 responses 21-25% larger than{tau} 2 and approximately 2 minutes faster. For cystic fibrosis epithelia, we find that elexacaftor/tezacaftor/ivacaftor (ETI) restores the apical membrane electrical response, resulting in a significant 84% higher{tau} 2 than{tau} 1 within the first 10 minutes. It also exhibits a greater than 8 min faster{tau} 2 response relative to{tau} 1 following 10 {micro}M GlyH-101 blocking (i.e., decreasing apical membrane permeability). These results demonstrate that EEIS enables rapid, quantitative, and biologically relevant measurement of apical and basolateral membrane properties in 16HBE epithelia. By providing membrane-specific resolution without the experimental challenges of intracellular electrodes, EEIS establishes a general framework for rapid, membrane-resolved electrophysiology with implications for therapeutic screening.

bioengineering↗

bioRxiv2026

Phosphoinositide Variant Fuels 53BP1 Oligomerization and Higher-Order Assembly in the DNA Damage Response

53BP1 nuclear bodies are dynamic structures with properties resembling biomolecular condensates, but the molecular determinants that govern 53BP1 higher-order assembly at DNA double-strand breaks (DSBs) remain to be established. Here, we show that 53BP1 condensation is stimulated by phosphatidylinositol 3-phosphate (PI(3)P) in vitro through a highly specific interaction with its C-terminal tandem BRCT domain (tBRCT). Consequently, mutational inactivation of the 53BP1 tBRCT domain compromised PI(3)P binding and suppressed 53BP1 optodroplet formation in vivo. We further show that rapid 53BP1 clustering following DNA damage precedes its stable assembly on DSB-flanking chromatin, requires its tBRCT, and is suppressed by sequestration of nuclear PI(3)P. Taken together, our findings identify PI(3)P binding as a mechanism that promotes the formation and maturation of 53BP1 condensate-like assemblies on damaged chromatin.

cell biology↗

bioRxiv2025

Smarcc1 is essential for the patterning of the optic stalk and differentiation of the optic nerve head astrocytes

The optic nerve is essential for vision, and its development depends on the transient neuroectodermal optic stalk, which forms alongside the optic cup through coordinated morphogenesis and differentiation into optic nerve astrocytes that provide lifelong support for retinal ganglion cell (RGC) axons. Here, we delineate key steps in astrocyte formation from the optic stalk and uncover stage- and lineage-specific roles of Smarcc1 (Baf155) and Smarcc2 (Baf170), scaffolding subunits of SWI/SNF chromatin remodeling complexes. Both factors are co-expressed in early retinal pigment epithelium (RPE) and optic stalk progenitors, with Smarcc2 persisting in differentiated derivatives, including RPE and optic nerve astrocytes. Conditional deletion using Dct-Cre revealed reciprocal compensation in pigmented lineages, whereas Smarcc1 loss uniquely caused optic nerve head (ONH) morphogenetic failure, characterized by glial lamina collapse, RGC degeneration, and progressive visual decline. Spatial transcriptomics and functional assays demonstrate that Smarcc1 drives the transition of dorsal optic stalk progenitors from a pigmented, RPE-like state to astrocyte progenitors by repressing pigment gene programs and enabling Pax2/Sox2 activity. After specification, Smarcc1 is required for glial lamina assembly, essential for ONH integrity and RGC survival. These findings establish a mechanism in which Smarcc1-mediated chromatin remodeling couples astrocyte progenitor specification and differentiation with local morphogenesis, ensuring long-term retinal function.

developmental biology↗

bioRxiv2025

Unify: Learning Cellular Evolution with Universal Multimodal Embeddings

Integrating single-cell RNA-sequencing (scRNA-seq) data across species is hindered by evolutionary divergence, technical batch effects, and the reliance on one-to-one orthologs. We present Unify, a transfer learning methodology that learns universal cell embeddings by defining functionally coherent, multi-modal macrogenes. This is achieved by combining RNA expression with embeddings from protein language models and general-purpose language models. Unify transcends species boundaries, enabling cross-species comparisons beyond strict gene-level homology. Unify corrects batch effects while preserving conserved biological signals across vast evolutionary distances and enables more accurate prediction of perturbation responses across species, such as from mouse to human. Applied to species separated by over 700 million years, Unify reconstructs more accurate multi-species cell-type evolutionary trees and uncovers convergent gene programs. Together, these results establish Unify as a powerful method for comparative single-cell genomics and evolutionary biology.

bioinformatics↗

bioRxiv2025

A bacterial PrimPol-reverse transcriptase hybrid protein has a proofreading exonuclease activity that can be transferred to other reverse transcriptases

Gene disruption analysis revealed that an E. coli PPRT protein, which has an N-terminal Primase-Polymerase (PrimPol) domain fused to a group II intron-like reverse transcriptase (RT) domain followed by a long C-terminal domain (CTD), contributes to a cellular oxidative DNA damage response in addition to its previously described function in phage defense. Biochemical analysis showed that the PrimPol domain has an error-prone DNA polymerase activity that enables read through of oxidation-induced DNA damage. Surprisingly, we found that the RT-like domain, in addition to synthesizing protein-primed DNAs for phage defense, has a 3 to 5 DNA exonuclease activity that functions in proofreading DNAs synthesized by the PrimPol domain. Extending these findings, we identified structural features that contribute to this proofreading activity, enabling us to associate it with both a group II intron-encoded and retroviral RT and suggesting general methods for incorporating proofreading activity into RTs.

molecular biology↗

bioRxiv2025

Population-specific brain charts reveal Chinese-Western differences in neurodevelopmental trajectories

Human brain charts provide unprecedented opportunities for decoding neurodevelopmental milestones and establishing clinical benchmarks for precision brain medicine 1-7. However, current lifespan brain charts are primarily derived from European and North American cohorts, with Asian populations severely underrepresented. Here, we present the first population-specific brain charts for China, developed through the Chinese Lifespan Brain Mapping Consortium (Phase I) using neuroimaging data from 43,037 participants (aged 0-100 years) across 384 sites nationwide. We establish the lifespan normative trajectories for 296 structural brain phenotypes, encompassing global, subcortical, and cortical measures. Cross-population comparisons with Western brain charts (based on data from 56,339 participants aged 0-100 years) reveal distinct neurodevelopmental patterns in the Chinese population, including prolonged cortical and subcortical maturation, accelerated cerebellar growth, and earlier development of sensorimotor regions relative to paralimbic regions. Crucially, these Chinese-specific charts outperform Western-derived models in predicting healthy brain phenotypes and detecting pathological deviations in Chinese clinical cohorts. These findings highlight the urgent need for diverse, population-representative brain charts to advance equitable precision neuroscience and improve clinical validity across populations.

neuroscience↗

bioRxiv2025

Evolutionary Genomics Guides Scalable Coral Probiotics for Climate Resilience

A universal bottleneck limiting probiotic efficacy in medicine, aquaculture, agriculture, and wildlife conservation is uncertain long-term colonization, necessitating repeated administration. We present an evolution-guided framework for probiotic identification based on genomic hallmarks of emerging host dependency, including widespread pseudogenization and insertion sequence proliferation driving genomic restructuring. Applied to coral reefs, we screened over 1,200 coral-associated bacterial isolates and identified Ruegeria MC10 as exhibiting these signatures. Its presence was associated with increased thermal tolerance of a model cnidarian. Following nursery application, MC10 persisted in reef corals for an 8-month monitoring period through a natural bleaching event, improving color retention and retaining algal photosynthesis performance. This work establishes a predictive, scalable pipeline for selecting persistent probiotics, directly addressing a central constraint on microbiome-based interventions across host systems.

microbiology↗

bioRxiv2024

Bacterial inoculation manipulates the coral epigenome

Environmental shifts can cause epigenetic modifications in corals, which are associated with changes in gene expression and physiology, though it remains unclear if associated bacteria can also induce such changes. Here, we inoculated nubbins of the coral Pocillopora verrucosa with an opportunistic pathogen, Vibrio coralliilyticus, and/or a coral probiotic, Cobetia sp., and subjected the nubbins to heat stress. We show that pathogen exposure led to distinct DNA methylation changes compared to the control, probiotic, and co-inoculation groups. We also demonstrate that DNA methylation correlates with coral gene expression and highlight genes altered by pathogen inoculation that showed similar responses in their expression and methylation. Notably, the coral probiotic was able to mitigate specific epigenetic changes, which correlated with increased stress resilience and higher coral survival rates. Thus, bacterial-induced changes to the coral epigenome may instigate long-term changes in host resilience.

molecular biology↗

bioRxiv2024

A Hypothalamic Circuit that Modulates Feeding and Parenting Behaviors

Across mammalian species, new mothers undergo considerable behavioral changes to nurture their offspring and meet the caloric demands of milk production1-5. While many neural circuits underlying feeding and parenting behaviors are well characterized6-9, it is unclear how these different circuits interact and adapt during lactation. Here, we characterized the transcriptomic changes in the arcuate nucleus (ARC) and the medial preoptic area (MPOA) of the mouse hypothalamus in response to lactation and hunger. Furthermore, we showed that heightened appetite in lactating mice was accompanied by increased activity of hunger-promoting agouti-related peptide (AgRP) neurons in the ARC. To assess the strength of hunger versus maternal drives, we designed a conflict assay where female mice chose between a food source or a chamber containing pups and nesting material. Although food-deprived lactating mothers prioritized parenting over feeding, hunger reduced the duration and disrupted the sequences of parenting behaviors in both lactating and virgin females. We discovered that ARCAgRP neurons directly inhibit bombesin receptor subtype-3 (BRS3) neurons in the MPOA, a population that governs both parenting and satiety. Selective activation of this ARCAgRP to MPOABRS3 circuit shifted behaviors from parenting to food-seeking. Thus, hypothalamic networks are modulated by physiological states and work antagonistically during the prioritization of competing motivated behaviors.

neuroscience↗

bioRxiv2023

STASCAN deciphers fine-resolution cell-distribution maps in spatial transcriptomics by deep learning

BackgroundThe spatial transcriptomics (ST) technologies have been widely applied to decode the spatial distribution of cells by resolving gene expression profiles in tissues. However, a fine-resolved spatial cell map is still limited by algorithmic tools and sequencing techniques. ResultsHere we develop a novel deep learning approach, STASCAN, which could define the spatial cellular distribution of both captured and uncharted areas by cell feature learning that combines gene expression profiles and histology images. STASCAN additionally adopts optional transfer learning and pseudo-labeling methods to improve the accuracy of the cell-type prediction from images. We have successfully applied STASCAN to enhance cell resolution, and revealed finer organizational structures across diverse datasets from various species and tissues generated from 10x Visium technology. STASCAN improves cell resolution of Schmidtea mediterranea datasets by six times and reconstructs more detailed 3D cell-type models. Furthermore, STASCAN could accurately pinpoint the boundaries of distinct cell layers in human intestinal tissue, specifically identify a micrometer-scale smooth muscle bundle structure in consistent with anatomic insights in human lung tissue, and redraw the spatial structural variation with enhanced cell patterns in human myocardial infarction tissue. Additionally, through STASCAN on embryonic mouse brain datasets generated by DBiT-derived MISAR-seq technology, the increased cellular resolution and distinct anatomical tissue domains with cell-type niches are revealed. Collectively, STASCAN is compatible with different ST technologies and has notable advantages in generating cell maps solely from histology images, thereby enhancing the spatial cellular resolution. ConclusionsIn short, STASCAN displays significant advantages in deciphering higher-resolution cellular distribution, resolving enhanced organizational structures and demonstrating its potential applications in exploring cell-cell interactions within the tissue microenvironment.

bioinformatics↗

bioRxiv2023

Monitoring norepinephrine release in vivo using next-generation GRABNE sensors

Norepinephrine (NE) is an essential biogenic monoamine neurotransmitter, yet researches using prototype NE sensors were limited by their low sensitivities. Here, we developed next-generation versions of GPCR activation-based NE sensors (GRABNE2m and GRABNE2h) with a superior response, high sensitivity and selectivity to NE both in vitro and in vivo. Notably, these sensors can detect NE release triggered by either optogenetic or behavioral stimuli in freely moving mice, producing robust signals in the locus coeruleus and hypothalamus. With the development of a novel transgenic mouse line, we recorded both NE release and calcium dynamics with dual-color fiber photometry throughout the sleep-wake cycle; moreover, dual-color mesoscopic imaging revealed cell type-specific spatiotemporal dynamics of NE and calcium during sensory processing and locomotion. Thus, these new GRABNE sensors are valuable tools for monitoring the precise spatiotemporal release of NE in vivo, providing new insights into the physiological and pathophysiological roles of NE.

neuroscience↗

bioRxiv2023

Establishment of hairy root culture and its genetic transformation of Stephania tetrandra S. Moore for production of BIAs

Metabolic engineering improvement of plants will play an essential role in future agriculture, but this largely depends on the establishment of genetic transformation. Stephania tetrandra S. Moore is a traditional Chinese medicine used for rheumatalgia that accumulates benzylisoquinoline alkaloids as its main active ingredients. Wild or farmed plants have remained the main source of these essential medicines, resulting in supply pressure due to the scarcity of wild plant resources and the slow growth rate in cultivation. Here, we constructed Agrobacterium rhizogenes (C58C1)-mediated hairy root culture and a co-transformation system in S. tetrandra to obtain a new source of bisbenzylisoquinoline alkaloids production. We show that the biomass of the hairy roots increased by 10-fold, and the content of tetrandrine reached 8.382 {+/-} 0.160 mg/g DW after 50 days of cultivation. In addition, overexpression of (R, S)-norcoclaurine 6-O-methyltransferase (6OMT) gene or treatment of hairy roots with methyl jasmonate (MJ) increased protoberberine alkaloid content. This work provides a method of obtaining hairy roots and a genetic transformation system for S. tetrandra, not only broadening the access to S. tetrandra resources, but also laying a foundation for further elucidation of the biosynthesis of tetrandrine and related alkaloids.

plant biology↗

bioRxiv2023

Time, Space and Single-Cell Resolved Molecular Trajectory of Cell Populations and the Laterality of the Body Plan at Gastrulation

Understanding of the molecular drivers of lineage diversification and tissue patterning during primary germ layer development requires in-depth knowledge of the dynamic molecular trajectories of cell lineages across a series of developmental stages of gastrulation1-7. Through computational modeling, we constructed at single-cell resolution a spatio-temporal compendium of the molecular trajectories of germ-layer derivatives in gastrula-stage mouse embryos. This molecular atlas infers the developmental trajectories of single-cell populations and the molecular network activity underpinning the specification and differentiation of the germ-layer lineages. Analysis of the heterogeneity of cellular composition of cell populations at defined positions in the epiblast revealed progressive diversification of cell types, mirroring the process of lineage allocation during gastrulation. A novel observation is the difference in the contribution of cells on contralateral sides of the epiblast to mesoderm derivatives of the early organogenesis embryo, and the enhanced BMP signaling activity in right-side mesoderm of E7.5 embryo. Perturbation of BMP signaling activity at late gastrulation led to randomization of left-right (L-R) molecular asymmetry in the lateral mesoderm of early-somite-stage embryo. Our findings indicate the asymmetric BMP activity during gastrulation may be critical for the symmetry breaking process associated with specification of L-R body asymmetry ahead of the acquisition of functionality of the L-R organizer.

developmental biology↗

bioRxiv2023

An autoinhibited state of 53BP1 revealed by chemical probes and protein engineering

The recruitment of 53BP1 to chromatin, mediated by its recognition of histone H4 dimethylated at lysine 20 (H4K20me2), is important for DNA double-strand break repair. Using a series of small molecule antagonists, we demonstrate a conformational equilibrium between an open and a pre-existing lowly populated closed state of 53BP1 in which the H4K20me2 binding surface is buried at the interface between two interacting 53BP1 molecules. In cells, these antagonists inhibit the chromatin recruitment of wild type 53BP1, but do not affect 53BP1 variants unable to access the closed conformation despite preservation of the H4K20me2 binding site. Thus, this inhibition operates by shifting the conformational equilibrium toward the closed state. Our work therefore identifies an auto-associated form of 53BP1 -- autoinhibited for chromatin binding -- that can be stabilized by small molecule ligands encapsulated between two 53BP1 protomers. Such ligands are valuable research tools to study the function of 53BP1 and have the potential to facilitate the development of new drugs for cancer therapy.

biochemistry↗

bioRxiv2023

Multi-omics and Pharmacological Characterization of Patient-derived Glioma Cell Lines

Glioblastoma (GBM) is the most common brain tumor and is currently incurable. Primary GBM cultures are widely used tools for screening potentially therapeutic drugs; however, there is a lack of genomic and pharmacological characterization of these primary GBM cultures. Here, we collected 52 patient-derived glioma cell (PDGC) lines and characterized them through whole- genome sequencing (WGS), RNA-seq, and drug response screening. We identified three molecular subtypes among PDGCs: mesenchymal (MES), proneural (PN), and oxidative phosphorylation (OXPHOS). Upon profiling the responses of PDGCs to 214 drugs, we found that the PN subtype PDGCs were sensitive to tyrosine kinase inhibitors, whereas the OXPHOS subtype PDGCs were sensitive to histone deacetylase inhibitors, oxidative phosphorylation inhibitors, and HMG-CoA reductase inhibitors. PN and OXPHOS subtype PDGCs stably formed tumors in vivo upon intracranial transplantation into immunodeficient mice, while most MES subtype PDGCs were incapable of tumorigenesis in vivo. In addition, profiling and follow-up investigations showed that the serum-free culture system used for PDGCs enriched and propagated rare MYC/MYCN- amplified glioma cells. Our study provides a resource for understanding primary glioma cell cultures and aiding clinical translation. SignificanceOur study provides a resource for patient-derived glioma cell lines (PDGCs) on transcriptome, genome, drug response, and tumorigenic abilities. PDGCs are categorized into PN, MES, and OXPHOS subtypes, with MES-subtype PDGCs incapable of tumorigenesis in vivo. Notably, the serum-free culture system for PDGCs enriches glioma cells with MYC/MYCN amplification.

cancer biology↗