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Biology subjects

Kong, C.

Publications and source records attributed to Kong, C..

At least 19 recordsLinked to original sources

Beyond the Plastisphere: Phylogenetic and Biogeographic Diversity of Marine Microorganisms with Putative Plastic-Degradation Potential

Plastic pollution is widespread in marine environments, yet the diversity of microorganisms and enzymes that may contribute to plastic degradation remains poorly understood. To identify promising candidates for future experimental studies, we investigated marine microorganisms with proteins related to enzymes previously associated with plastic degradation. Using PlasticDB and the NCBI RefSeq protein database, we identified 523 distinct protein sequences from microorganisms with documented marine provenance. We then examined their evolutionary relationships, environmental origins, and geographic distributions to assess how these candidate proteins are distributed across marine microbial diversity. Only 10.3% of the curated sequence assignments originated from plastisphere or marine-biofilm records, while most were associated with other marine environments, particularly marine hosts. These findings suggest that searches focused exclusively on plastic-associated biofilms may overlook a substantial portion of the marine microbial diversity relevant to plastic transformation. The identified proteins include candidates for direct polyester hydrolysis as well as proteins that may contribute to oxidative chemistry or cellular protection during plastic-associated metabolism. Together, these phylogenetic and biogeographic analyses establish a targeted resource for the discovery and isolation of marine-derived genes with potential roles in plastic transformation, providing experimentally tractable candidates for biochemical characterization and future development of microbial and enzyme-based plastic recycling strategies.

microbiology↗

Protonation- and substrate-regulated dimer opening couples brain-type creatine kinase to vesicular and actin-remodeling membranes

Brain-type creatine kinase (CK-BB) buffers local ATP demand through reversible phosphotransfer between ATP and phosphocreatine, yet how this soluble metabolic enzyme engages membrane compartments is unknown. Here, we combine fluorescence microscopy, DEER spectroscopy, hydrogen-deuterium exchange and native mass spectrometry, DEER- and AlphaFold-guided modeling, and long-timescale molecular dynamics to define the pH- and substrate-regulated conformational landscape governing CK-BB membrane association. Acidification promotes curvature-sensitive membrane binding and redistributes endogenous and recombinant CK-BB from diffuse cytosolic pools to punctate vesicular structures and membrane ruffles. Substrates independently promote curvature-sensitive association at neutral pH. DEER and modeling reveal an asymmetric dimer in which the convex surface remains restrained, whereas the concave catalytic-regulatory surface samples pH- and substrate-dependent intermediates. We identify progressive dimer opening as a novel regulatory mechanism whereby acidification and substrate binding increase dynamics across the convex surface and N-terminal dimer interface, generating membrane-competent conformations that facilitate curvature sensing and membrane association. Substrate binding buffers acid-induced deprotection while preserving dynamics near the His191/Ser199 regulatory interface. These findings establish CK-BB as a previously unrecognized curvature-sensitive metabolic enzyme and define dimer dynamics as a molecular switch coupling protonation and substrate occupancy to curved-membrane recognition and localized ATP regeneration, with potential relevance to neurodegeneration and cellular stress.

biophysics↗

The genetic repertoire of the deep sea: from sequence to structure and function

The deep sea as the largest and maybe most hostile environment on Earth is still underexplored especially regarding its genetic repertoire. Yet, previous work has revealed significant habitat-specific deep-sea biodiversity. Here, we present an integrated deep-sea genetic dataset comprising 502 million nonredundant genes from 2,138 samples and 2.4 million predicted structures, and used it to link specific protein structures with genetic variants associated with life in the deep sea and to assess their biotechnology potential. Combining global sequence analysis with biophysical and biochemical measurements revealed unprecedented sequence diversity, yet substantial structural conservation of proteins. Especially proteins involved in replication, recombination, and repair were identified to be under rapid evolution and with specialized properties. Among these, a structurally divergent helicase exhibited advantages in controlling nanopore sequencing speed. Thus, our work positions the deep sea as a unique evolutionary engine that generates and hosts genetic diversity and bridges genetic knowledge with biotechnology.

bioinformatics↗

Ultrashort optical-pin excitation for scattering brain imaging

Imaging neural structures deep in brain tissue is central to understanding brain function, yet remains fundamentally limited by strong optical scattering and the requirement for accurate three-dimensional (3D) optical sectioning. Laser-scanning microscopy is a promising technique for brain imaging; however, maintaining excitation focus integrity in scattering media while preserving axial confinement poses a persistent photonic challenge. Here we introduce the optical pin, an ultrashort excitation regime engineered at the angular-spectrum level to address this limitation. By broadening the transverse angular bandwidth of a Bessel-type field while preserving its conical momentum-space architecture, the optical pin introduces a controlled longitudinal wave-vector spread that compresses the axial interference length to the micrometer scale, restoring Gaussian-like sectioning without sacrificing multi-angle interference. This excitation design yields substantially enhanced imaging performance, including [~]1.5-fold contrast improvement and [~]2.6-fold increased robustness to scattering. We validate the approach across transparent, scattering, and biological specimens, including bead phantoms, C. elegans, and mouse brain tissue. As a system-level excitation strategy, the optical pin is readily compatible with existing laser-scanning microscopy platforms and is particularly suited for scattering-limited brain imaging.

neuroscience↗

Kilohertz-rate two-photon voltage imaging of population dynamics in vivo

Understanding how neural circuits compute requires capturing voltage dynamics across large neuronal populations with millisecond resolution in vivo. However, two-photon voltage imaging remains fundamentally limited by a trade-off among imaging speed, field of view, and excitation efficiency. We introduce HS2PM, a hybrid scanning two-photon microscope that overcomes this bottleneck, enabling kilohertz-rate imaging over a 650 x 524 m2 field of view at single-cell resolution while preserving the photon efficiency of single-point excitation. HS2PM stably records deep-layer membrane potentials from over 160 neurons simultaneously, with minimal photobleaching and phototoxicity. It resolves both spikes and subthreshold voltage dynamics in vivo, revealing how these jointly shape sensory adaptation and population coding. Beyond voltage imaging, HS2PM supports high-speed fluorescence lifetime and vascular flow imaging, establishing a multimodal platform for dissecting fast circuit dynamics with precision previously inaccessible to optical methods.

neuroscience↗

A Compact Two-Photon Module for Simultaneous Dual-Depth, Multi-Region in vivo Brain Imaging

Understanding how distributed brain regions interact across cortical depths is crucial for uncovering the neural basis of behavior and cognition. Two-photon microscopy (2PM) excels at imaging the superficial layer, while three-photon microscopy (3PM) penetrates deep tissues but lacks sufficient speed for capturing fast superficial dynamics. Here, we present a compact two-photon imaging module (2PIM) that seamlessly integrates with existing 3PM to achieve simultaneous, high-speed imaging of superficial and deep brain regions, while preserving the deep tissue penetration of 3PM. This dual-modality system allows for remote and independent control of imaging planes in both axial and lateral dimensions. Leveraging this technology, we discovered context-dependent modulation of hippocampal CA1 and visual cortex responses to identical tactile stimuli, layer-specific temporal dynamics in sensory cortex during air puff stimulation, and depth-divergent neuronal activity patterns in motor cortex across acute-to-chronic pain. These results highlight the systems potential for dissecting the spatiotemporal coordination of distributed brain circuits.

bioengineering↗

MONTAGE: A Computation Framework to Identify Spatially Resolved Functional Enrichment Gradients in the Tissue Microenvironment via Spatial Communities

Single-cell spatial-omics has advanced our understanding of how tumor microenvironment contributes to cancer progression. However, most single-cell spatial-omics studies focus on cell types and neighborhoods, offering limited information about functional and clinical relevance of cellular organization. We introduce MONTAGE, a computational framework to reconstruct, functionally analyze, and identify clinically relevant cellular spatial communities (SCs). MONTAGE generates a gene signature matrix of SCs from integrated atlases that offer single-cell resolution with transcriptomics, and reconstructs tissue maps ("montages"), reflecting sequential SC compositional changes along spatial gradients of biological function enrichments. The MONTAGE signature matrix can also be used to deconvolve bulk and spot-based spatial transcriptomic data, and combining with clinical metadata, allows assessing SC clinical relevance. In a head and neck cancer study, MONTAGE reveals SCs enriched with malignant cells and granulocytes shifting to SCs enriched with macrophages and fibroblasts along gradient of epithelial-mesenchymal transition, and clinical prognostic significance of the SCs.

systems biology↗

Large-scale single-neuron recording using the uFINE array in human cortex

Monitoring neural population activity at single-cell resolution is essential for driving fundamental research and clinical innovations. However, translating advanced recording techniques from animal models to humans remains a significant challenge. Flexible neural electrodes have recently emerged as powerful tools for large-scale single-unit recordings due to their superior biocompatibility and high recording density. Here, we demonstrate reliable, high-density single-unit recordings during intraoperative procedures in human patients using ultra-Flexible Implantable Neural Electrode (uFINE) arrays. The uFINE array exhibited sufficient mechanical robustness to maintain structural integrity throughout surgical operations. We successfully recorded 616 single units from 10 patients, with up to 135 single units simultaneously recorded. The flexibility of uFINE array minimized signal disturbances from brain pulsations, enabling stable and continuous single-unit detection. Stimulus and response tuning were observed at the level of individual neurons in awake patients. This uFINE-based recording approach offers unique opportunities to investigate human-specific cognitive functions and develop next-generation brain-machine interfaces.

bioengineering↗

Role of Complexin 2 in the regulation of hormone secretion from the islet of Langerhans

Regulated secretion of insulin from {beta}-cells, glucagon from -cells, and somatostatin from {delta}-cells is necessary for the maintenance of glucose homeostasis. The release of these hormones from pancreatic islet cells requires the assembly and disassembly of the SNARE protein complex to control vesicle fusion and exocytosis. Complexin 2 (Cplx 2) is a small soluble synaptic protein that participates in the priming and release steps of vesicle fusion. It plays a dual role as a molecular switch that first clamps and prevents fusion pore opening, and subsequently undergoes a conformational change upon Ca2+ binding to synaptotagmin to facilitate exocytosis. Using a Cplx 2 knockout (KO) mouse model, we show a direct inhibitory role of Cplx 2 for glucagon and somatostatin secretion, along with an indirect role in the paracrine inhibition of insulin secretion by somatostatin. Deletion of Cplx 2 increases glucagon and somatostatin secretion from intact mouse islets, while there is no difference in insulin secretion between WT and Cplx 2 KO islets. The normal paracrine inhibition of insulin secretion by somatostatin is disrupted in Cplx 2 KO islets. On the contrary, deletion of Cplx 2 did not affect the known role of somatostatin in the paracrine inhibition of glucagon at elevated glucose levels, since the paracrine inhibition of glucagon secretion by somatostatin is similar for both WT and Cplx 2 KO islets. In both {beta}- and -cells, the secretion profiles are parallel to Ca2+ activity changes following somatostatin treatment of WT and Cplx 2 KO islets. The loss of paracrine inhibition of insulin secretion is substantiated by direct measurements of insulin vesicle fusion events in Cplx 2 KO islets. Together, these data show a differential role for Cplx 2 in regulating hormone secretion from pancreatic islets.

cell biology↗

A VgrG2b fragment cleaved by caspase-11/4 promotes Pseudomonas aeruginosa infection through suppressing the NLRP3 inflammasome

The T6SS of Pseudomonas aeruginosa plays an essential role in the establishment of chronic infections. Inflammatory cytokines mediated by inflammasomes are crucial for the body to resist bacterial infections. Here we found that during the infection of P. aeruginosa, non-canonical inflammasome was activated in macrophages, but the activation of downstream NLRP3 inflammasome was inhibited. The VgrG2b of P. aeruginosa is recognized and cleaved by caspase-11, generating a free C-terminal fragment. The VgrG2b C-terminus can bind to NLRP3, inhibiting the activation of the NLRP3 inflammasome by rejecting NEK7 binding to NLRP3. Administrating a specific peptide that inhibits the cleavage of VgrG2b by caspase-11 to mice can significantly improve their survival rate during infection. Our discovery elucidates a mechanism by which P. aeruginosa inhibits host immune response, providing a new approach for the future clinical treatment of P. aeruginosa infections.

immunology↗

The role of mu-opioid receptors in pancreatic islet alpha cells

30% of people in the United States have diabetes or pre-diabetes. Many of these individuals will develop diabetic neuropathy as a comorbidity, which is often treated with exogenous opioids like morphine, oxycodone, or tramadol. Although these opioids are effective analgesics, growing evidence indicates that they may directly impact the endocrine pancreas function in human and preclinical models. One common feature of these exogenous opioid ligands is their preference for the mu opioid receptor (MOPR), so we aimed to determine if endogenous MOPRs directly regulate pancreatic islet metabolism and hormone secretion. We show that pharmacological antagonism of MOPRs enhances glucagon secretion, but not insulin secretion, from human islets under high glucose conditions. This increased secretion is accompanied by increased cAMP signaling. mRNA expression of MOPRs is enriched in human islet -cells, but downregulated in T2D islet donors, suggesting a link between metabolism and MOPR expression. Conditional genetic knockout of MOPRs in murine -cells increases glucagon secretion in high glucose conditions without increasing glucagon content. Consistent with downregulation of MOPRs during metabolic disease, conditional MOPR knockout mice treated with a high fat diet show impaired glucose tolerance, increased glucagon secretion, increased insulin content, and increased islet size. Finally, we show that MOPR-mediated changes in glucagon secretion are driven, in part, by KATP channel activity. Together, these results demonstrate a direct mechanism of action for endogenous opioid regulation of endocrine pancreas.

physiology↗

Convergent Transcriptomic Evidence Reveals the Dysfunctional Quantitative Mechanism of Synaptic Plasticity Control in ASD

A prominent endophenotype in Autism Spectrum Disorder (ASD) is synaptic plasticity dysfunction, yet the molecular mechanism remains elusive. As a prototype, we investigated the postsynaptic signal transduction network in glutamatergic neurons and integrated transcriptomics to unveil the malfunction of translation control. We devised an innovative and highly dependable pipeline to transform our acquired signal transduction network into a mRNA Signaling-Regulatory Network (mSiReN) and analyze it at the RNA level. We employed Cell-Specific Network Inference via Integer Value Programming and Causal Reasoning (CS-NIVaCaR) to identify core modules and Cell-Specific Probabilistic Contextualization for mRNA Regulatory Networks (CS-ProComReN) to quantitatively reveal activated sub-pathways involving MAPK1, MKNK1, RPS6KA5, and MTOR across different cell types in ASD. The results indicate that specific pivotal molecules, such as EIF4EBP1 and EIF4E, lacking Differential Expression (DE) characteristics and responsible for protein translation with long-term potentiation (LTP) or long-term depression (LTD), are dysregulated. We further uncovered distinct activation patterns causally linked to the EIF4EBP1-EIF4E module in excitatory and inhibitory neurons. Importantly, our work has introduced a methodology for leveraging extensive transcriptomics data to parse the signal transduction network, transforming it into mSiReN, and mapping it back to the protein level. These algorithms can serve as potent tools in systems biology to analyze other omics and regulatory networks. Furthermore, the biomarkers within the activated sub-pathways, revealed by identifying convergent dysregulation, illuminate potential diagnostic and prognostic factors in ASD.

systems biology↗

Synthetic whole-slide image tile generation with gene expression profiles infused deep generative models

The acquisition of multi-modal biological data for the same sample, such as RNA sequencing and whole slide imaging (WSI), has increased in recent years, enabling studying human biology from multiple angles. However, despite these emerging multi-modal efforts, for the majority of studies only one modality is typically available, mostly due to financial or logistical constraints. Given these difficulties, multi-modal data imputation and multi-modal synthetic data generation are appealing as a solution for the multi-modal data scarcity problem. Currently, most studies focus on generating a single modality (e.g. WSI), without leveraging the information provided by additional data modalities (e.g. gene expression profiles). In this work, we propose an approach to generate WSI tiles by using deep generative models infused with matched gene expression profiles. First, we train a variational autoencoder (VAE) that learns a latent, lower dimensional representation of multi-tissue gene expression profiles. Then, we use this representation to infuse generative adversarial networks (GAN) that generate lung and brain cortex tissue tiles, resulting in a new model that we call RNA-GAN. Tiles generated by RNA-GAN were preferred by expert pathologists in comparison to tiles generated using traditional GANs and in addition, RNA-GAN needs fewer training epochs to generate high-quality tiles. Finally, RNA-GAN was able to generalize to gene expression profiles outside of the training set, showing imputation capabilities. A web-based quiz is available for users to play a game distinguishing real and synthetic tiles: https://rna-gan.stanford.edu/ and the code for RNA-GAN is available here: https://github.com/gevaertlab/RNA-GAN.

bioinformatics↗

Tumor landscape of epithelial ovarian cancer highlights that EGR1 drives tumor invasion at single-cell resolution

Identifying underlying molecular mechanisms and biomarkers of epithelial ovarian carcinoma (EOC) proliferation and metastasis remains challenging. Patients of EOC are usually diagnosed at an advanced stage and the availability of invasion-related targets is limited. Herein, we explored the single-cell RNA sequencing (scRNA-seq) dataset of EOC and defined tumor physiological reprograming compared to bulk RNA-seq. The energy metabolism and anti-apoptotic pathway was found as critical contributors to intratumor heterogeneity. Moreover, hypoxia, oxidative phosphorylation (OXPHOS) and glycolysis were positively correlated, which have biologically activity trajectories during epithelial mesenchymal transition (EMT). The HMGH1, EGR1 and RUNX1 were found to be critical inducers of the EMT process in EOC. Experimental validation revealed that suppressed EGR1 decreased the expression of FAS and HSPG2 and associating with EMT progression in EOC. In tumor microenvironment (TME), CAFs were found have significant contribution to tumor immune infiltration and metastasis and accumulation of CAFs was associated with poorer patient survival. In conclusion, physiological features and molecular mechanisms in the TME of EOC were revealed and provided effective targets for the suppression of tumor metastasis.

bioinformatics↗

A multiplexed in vivo approach to identify driver genes in small cell lung cancer

Small cell lung cancer (SCLC) is a highly lethal form of lung cancer. The high mutation burden in SCLC cells makes it challenging to predict key drivers of SCLC from genome sequencing data, thereby hindering the identification of possible therapeutic targets. Here we develop a quantitative multiplexed approach based on lentiviral barcoding with somatic CRISPR/Cas9-mediated genome editing to functionally investigate candidate regulators of tumor initiation and growth in genetically engineered mouse models of SCLC. Lentiviral vector-mediated SCLC initiation was greatly enhanced by naphthalene pre-treatment, enabling high multiplicity of tumor clones for analysis through high-throughput sequencing methods. Based on a meta-analysis across multiple human SCLC genomic datasets, we quantified the impact of inactivating 39 genes across many candidate pathways and captured both positive and detrimental effects on SCLC initiation and progression upon gene inactivation. This analysis and subsequent validation in human SCLC cells identified TSC1 in the PI3K-AKT-mTOR pathway as a robust tumor suppressor in SCLC. This new approach should illuminate novel drivers of SCLC, facilitate the development of precision therapies for defined SCLC genotypes, and identify new therapeutic targets.

cancer biology↗

Neuronal mimicry generates an ecosystem critical for brain metastatic growth of SCLC

Brain metastasis is a major cause of morbidity and mortality in cancer patients. Here we investigated mechanisms allowing small-cell lung cancer (SCLC) cells to grow in the brain. We show that SCLC cells undergo a cell state transition towards neuronal differentiation during tumor progression and metastasis, and that this neuronal mimicry is critical for SCLC growth in the brain. Mechanistically, SCLC cells re-activate astrocytes, which in turn promote SCLC growth by secreting neuronal pro-survival factors such as SERPINE1. We further identify Reelin, a molecule important in brain development, as a factor secreted by SCLC cells to recruit astrocytes to brain metastases in mice. This recruitment of astrocytes by SCLC was recapitulated in assembloids between SCLC aggregates and human cortical spheroids. Thus, SCLC brain metastases grow by co-opting mechanisms involved in reciprocal neuron-astrocyte interactions during development. Targeting such developmental programs activated in this cancer ecosystem may help treat brain metastases.

cancer biology↗

Digestion, fermentation, and pathogen anti-adhesive properties of the hMO-mimic di-fucosyl-β-cyclodextrin

ScopeHuman milk is widely acknowledged as the best food for infants, and that is not just because of nutritional features. Human milk also contains a plethora of bioactive molecules, including a large set of human milk oligosaccharides (hMOs). Especially fucosylated hMOs have received attention for their anti-adhesive effects on pathogens by preventing attachment to the intestinal wall. Because hMOs are generally challenging to produce in sufficient quantities to study and ultimately apply in (medical) infant formula, hMO mimics are interesting compounds to produce and evaluate for their biological effects. Methods and resultsWe investigated the digestion, fermentation, and pathogen anti-adhesive capacity of the novel hMO mimic di-fucosyl-{beta}-cyclodextrin (DF{beta}CD). We establish that DF{beta}CD is not digested by -amylase and also resists fermentation by the microbiota from a 9 month-old infant. In addition, we reveal that DF{beta}CD blocks adhesion of enterotoxigenic E. coli (ETEC) to Caco-2 cells, especially when DF{beta}CD is pre-incubated with ETEC prior to addition to the Caco-2 cells. ConclusionOur results suggests that DF{beta}CD functions through a decoy effect. We expect that our results inspire the generation and biological evaluation of other fucosylated hMOs and mimics, to obtain a comprehensive overview of the anti-adhesive power of fucosylated glycans.

microbiology↗

1RS.1BL molecular resolution provides novel contributions to wheat improvement

Wheat-rye 1RS.1BL translocation has a significant impact on wheat yield and hence food production globally. However, the genomic basis of its contributions to wheat improvement is undetermined. Here, we generated a high-quality assembly of 1RS.1BL translocation comprising 748,715,293 bp with 4,996 predicted protein-coding genes. We found the size of 1RS is larger than 1BS with the active centromere domains shifted to the 1RS side instead of the 1BL side in Aikang58 (AK58). The gene alignment showed excellent synteny with 1BS from wheat and genes from 1RS were expressed well in wheat especially for 1RS where expression was higher than that of 1BS for the grain-20DPA stage associated with greater grain weight and negative flour quality attributes. A formin-like-domain protein FH14 (TraesAK58CH1B01G010700) was important in regulating cell division. Two PPR genes were most likely the genes for the multi fertility restoration locus Rf multi. Our data not only provide the high-resolution structure and gene complement for the 1RS.1BL translocation, but also defined targets for enhancing grain yield, biotic and abiotic stress, and fertility restoration in wheat.

genomics↗