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Lin, Y.

Publications and source records attributed to Lin, Y..

At least 73 records · Page 4Linked to original sources

Disentangled multimodal evolutionary representations for cross-virus predictive modeling of antigenic change

Antigenic evolution drives immune escape and complicates early assessment of emerging pathogens, especially when genomic surveillance is sparse and functional measurements lag behind real-world spread. Early prediction and generalization to unknown viruses require faithful and information-rich representations of viral evolution, a need that is not fully addressed by existing protein language model-based approaches. Here we introduce DERIVE, a flow-based generative framework that learns a disentangled latent representation of multimodal evolutionary history by integrating sequence homology with physicochemical and structural features. Using only pre-pandemic SARS-CoV-2 sequences, DERIVE prioritizes high-risk mutations, reconstructs strain-level evolutionary trajectories, forecasts immune escape and prevalence trends, and produces mutation-level effect maps. The learned representation transfers robustly across viral families, with strong concordance to functional data for influenza virus, HIV, rabies lyssavirus and chikungunya virus. Together, these results position DERIVE as a generalizable and interpretable framework for anticipating antigenic evolution and supporting early, actionable assessment of future "Disease X" threats.

bioinformatics↗

Promoter editing of starch branching enzyme IIb and granule-bound starch synthase I balances resistant starch content and amylose content in rice

Increasing attention is being focused on the glycemic index (GI) of daily food for humans, and the resistant starch content (RSC) is an important indicator of GI for starch-rich staple foods. In recent years, some studies revealed that the loss function of single or multiple key enzymes in the primary pathway of starch synthesis substantially increases RSC in rice, such as starch branching enzyme IIb (BEIIb) and soluble starch synthase IIIa (OsSSIIIa). However, a noteworthy negative characteristic of these high RSC mutants is the substantially increased amylose content (AC). AC as a major determinator of rice eating quality, must not be higher than an acceptable limit for most consumers. To solve this problem, in this study, we adopted two promoter editing (PE) editing strategies to develop rice germplasms with a better balance of RSC and AC: one is to edit the promoter of BEIIb in a low AC rice variety, another is to edit the promoter of Waxy (Wx) gene in a BEIIb loss of function mutant. Using AC[≤]20%, which is the range of premium quality rice in China as a criteria, we finally obtained 2 homozygous lines with significantly increased RSC ([≥]5%) in the NG46 background by promoter editing of BEIIb and 1 homozygous line in the YouTang2 (YT2, a BEIIb mutant) background by promoter editing of Wx gene. Further analysis revealed that AC and the amount of long-chain branches of amylopectin are positively correlated with RSC in the population of BEIIb PE lines. However, unexpectedly, the Wx PE-line with substantially decreased AC (17.7%) also showed significantly increased RSC (16.9%). Our study not only produces useful germplasms for the high RSC rice breeding in the future but also provides an insight into understanding the relationship between AC and RSC in defective BEIIb rice.

plant biology↗

Disease diagnosis via sperm motility variations induced by body fluids in bioassay

Precise diagnosis of high-risk conditions such as cardiovascular and cerebrovascular diseases still remains a challenge. We previously developed a microfluidic chip for sperm selection and observed that sperm motility is highly sensitive to environmental changes. Building on this finding, we hypothesized that motility traits of sperm could be differentially modulated by body fluids from healthy versus diseased individuals, thereby serving as potential biomarkers for disease diagnosis. To test this hypothesis, we designed a diagnostic system in which mouse sperm were co-incubated with serum samples from patients with myocardial infarction, cerebral infarction, and pancreatitis, along with matched healthy controls. Key kinematic parameters--including motility rate (MR), curvilinear velocity (VCL), straight-line velocity (VSL), linearity (LIN), and amplitude of lateral head displacement (ALH)--were analyzed using a multiparameter sperm quality analysis system. The results revealed that disease-specific serum induced distinct and reproducible changes in sperm motility patterns, enabling accurate discrimination between healthy and pathological conditions. Evaluation of these motility parameters demonstrated high diagnostic performance, with area under the receiver operating characteristic curve (AUC) values ranging from 0.719 to 0.888. This sperm-based bioassay offers a non-invasive, rapid, and cost-effective platform for disease detection and personalized health assessment, with the potential to complement existing diagnostic approaches.

bioengineering↗

Unlocking Ultrasensitive Phosphoproteomics of Nanoscale Samples: A Rapid IMAC Enrichment Platform Using Ti-PAN Tip

Protein phosphorylation is a critical mechanism in cellular signal transduction, playing essential roles in various cellular processes. However, significant challenges of their low abundance, high dynamic range, and complexity are especially prominent for accurate phosphoproteome analysis in nanoscale samples, such as oocytes, where misregulation of phosphorylation can lead to infertility. In this study, we developed a novel phosphopeptide enrichment tip (Ti-PAN) using highly hydrophilic textile PAN fibers, enabling rapid in-situ one-tip IMAC enrichment in just 8 minutes. This approach not only minimizes sample loss but also enhances analytical sensitivity and is easily adaptable to automation for high-throughput applications, demonstrating excellent recovery (>94%) and outstanding selectivity for phosphopeptides with remarkable resistance to interference up to 1:5000. By integrating it with a compatible sample preparation workflow based on n-dodecyl {beta}-D-maltoside (DDM) lysis with the high-sensitivity MS data acquisition method of turboDDA, comprehensive mapping of phosphosites in microsamples was achieved, including those from the ERK interactome, mouse brain slices, and oocytes. Using this approach, we identified 2,139 to 11,296 phosphosites across 645 to 2,168 phosphoproteins from samples ranging from 100 to 100,000 cells. Furthermore, we successfully applied this strategy to analyze the phosphoproteome of mouse oocytes at different developmental stages, using as few as 5 oocytes per sample. This led to the identification of 2,709 phosphosites on 701 phosphoproteins, revealing several key kinases involved in meiotic resumption and oocyte maturation, including STK4 (serine/threonine kinase 4) and DYRK3 (dual specificity tyrosine phosphorylation-regulated kinase 3). To our knowledge, this represents the deepest coverage of phosphoproteomes from such minimal oocyte material reported to date, offering valuable mechanistic insights into developmental controls during oocyte maturation. This Ti-PAN-based method provides a robust, versatile, and automatable platform for large-scale, highly sensitive phosphopeptide enrichment, substantially advancing phosphoproteomic studies in complex biological systems.

biochemistry↗

MicroGenomer: A Foundation Model for Transferable Microbial Genome Representations Enabling Multi-scale Genomic Understanding and Ecophysiological Trait Prediction

Microorganisms underpin global biogeochemical cycles and represent a vast, underexplored reservoir for sustainable biotechnology and human health. Their diversity, arising from the interplay of numerous genes within holistic genomic contexts, dictates complex ecophysiological traits across varied environments. To bridge the gap between complex genomic sequences and associated biological functions and phenotypic outcomes, we present MicroGenomer, a foundation model for transferable microbial genome representations enabling multi-scale genomic understanding and ecophysiological trait prediction. MicroGenomer leverages a hierarchical training strategy comprising pre-training on large-scale genomic sequences (234.5 billion base pairs), domain-specific mid-training using the GTDB-curated marker gene set, and task-specific post-training. Despite a streamlined architecture of 470 million parameters, MicroGenomer achieves performance on key tasks competitive with models nearly 85 times its size. Advancing beyond established gene-scale encoders, MicroGenomer generates robust embeddings at the genome scale for downstream modeling. Extensive evaluations demonstrate that MicroGenomer effectively captures phylogenetic structures in species space, excelling in geneand genome-scale understanding as well as ecophysiological trait prediction. The practical utility of these capabilities is further demonstrated by targeted wet-lab validation on newly isolated strains, indicating that MicroGenomers predictions provide reliable guidance for biological experiments. Collectively, MicroGenomer offers a high-performance, resource-efficient framework that transforms raw sequence data into actionable biological insights, providing a powerful foundation for microbiome research and biotechnology.

bioinformatics↗

Tirzepatide Synergizes with Leptin on Weight Loss and Restoring Metabolic Homeostasis in Diet-induced Obesity Model

Leptin resistance limits anti-obesity efficacy. We identified a leptin-sensitizing mechanism through tirzepatide (TZP), a glucagon-like peptide-1 receptor (GLP-1R) and glucose-dependent insulinotropic polypeptide receptor (GIPR) dual-agonist. Our tirzepatide clinical trial revealed that circulating leptin levels at baseline correlated with weight loss efficacy in patients with obesity, suggesting leptin and tirzepatide could interact to achieve stronger effects on weight loss. Next, we utilized the diet-induced obesity (DIO) mice and demonstrated the synergistic effects of tirzepatide and leptin combination (TZP+Lep) on weight loss. TZP+Lep treatment further improved hepatic insulin sensitivity and upregulated thermogenetic gene expression in brown adipose tissue. Metabolic profiling under thermoneutrality revealed TZP+Lep treatment further reduced food intake and increased energy expenditure. Tirzepatide sensitized leptin signaling in hypothalamic pro-opiomelanocortin (POMC) and GLP-1R expressing neurons. TZP+Lep synergistically increased POMC neuronal firing by decreasing the inhibitory postsynaptic input. Together, our work showed combining tirzepatide and leptin as a potential way for better maintenance of metabolic homeostasis in obesity management. HighlightsO_LITirzepatide and leptin synergistically promote weight loss through reduced food intake and increased energy expenditure. C_LIO_LITirzepatide and leptin synergistically improve insulin sensitivity and metabolic homeostasis with altered hepatic and adipose gene expression. C_LIO_LITirzepatide sensitizes leptin signaling in hypothalamic GLP-1R and POMC neurons. C_LIO_LITirzepatide and leptin synergistically increase POMC neuronal firing by decreasing inhibitory postsynaptic input. C_LI

neuroscience↗

Charting the cognitive development of children using adult 'polygenic g scores'

The most highly predictive polygenic scores in the behavioural sciences are for cognitive traits, especially general cognitive ability (g) and educational attainment. We combined polygenic scores derived from genome-wide association studies of adult g and educational attainment to create adult polygenic g scores which we used to chart the course of cognitive development of 10,000 white British children from toddlerhood through early adulthood. We integrated cross-sectional regression, latent growth curve, and confirmatory factor analysis to systematically characterise cognitive development. Polygenic g score showed minimal prediction in toddlerhood, modest prediction in childhood, and substantial prediction by early adulthood accounting for 12% of the variance. Higher polygenic g scores were associated with faster cognitive growth in latent growth models. Prediction was strongest for a cross-time latent cognitive factor (15%) capturing cognitive ability across development. By integrating polygenic prediction directly into a structural equation model framework, we provided a theoretical upper bound of genetic influences on g under minimal measurement error. We also examined the polygenic g scores prediction of educational achievement, behaviour problems, and anthropometric outcomes and found similar developmental increases in prediction for educational achievement. Together, our findings demonstrate that adult polygenic g scores can be a useful tool for charting the development of cognitive traits.

genetics↗

Theta and beta account for the two-impacted components of social influence on risk decision-making

Social influence in risky decision-making means changing risky behavior after observing others choices. Although attributes prioritization can alter subjective value of a particular option while choice bias can affect the tendency toward it, previous studies have not simultaneously examined these two components. Here, participants made risky or safety choices, observed a model whose risk preference either matched (control) or opposed (inconsistent) their own, then repeated the task. Behavioral and EEG data were collected, and drift-diffusion model (DDM) was used to decompose different components. After observing an opposing preference, risk-seeking participants chose safety options more often, and risk-aversion participants chose risky options more often, indicating social influence. Model comparison favored an attribute-wise DDM. Social influence altered two distinct components in risky decisions: the weight of amount in value computation (more negative after observing the opposing model) and the starting point (shifting toward the options chosen more often). Multivariate pattern analysis linked these components to distinct neural signatures: theta activity ({approx}500 ms after option onset) tracked the amount weighting, whereas pre-option beta activity tracked the starting point. Together, the results show that social influence reshapes risky decisions by reweighting amount and shifting choice bias, each supported by dissociable electrophysiological dynamics.

animal behavior and cognition↗

Torsins Organize CLCC1 Assembly to Safeguard ER Bilayer and Lipid Homeostasis

The TMEM41B scramblase and its regulatory partner CLCC1 initiate lipid flux by equilibrating newly-synthesized phospholipids across the endoplasmic reticulum (ER) bilayer, a fundamental process required for diverse events ranging from membrane biogenesis to bulk lipid supply. Loss of CLCC1/TMEM41B causes ER bilayer imbalance, inducing giant ER-enclosed lipid droplets (geLDs) and driving rapid progression into severe MASH. Here we identify CLCC1 as the long-missing client of the lumenal Torsin ATPases, which selectively engage oligomerized CLCC1 at sites of ER bilayer imbalance. Hepatic TorsinA inactivation triggers geLD formation amid disrupted lipoprotein biogenesis and severe MASH, closely phenocopying CLCC1/TMEM41B deficiency. Mechanistically, Torsins act as foldases that drive CLCC1 oligomerization for its recruitment to imbalanced bilayers. Remarkably, ectopic CLCC1 expression reverses cellular and systemic lipid disorders arising from hepatic TorsinA deficiency. Hence, Torsin ATPases emerge as fundamental regulators that organizes CLCC1 and the downstream TMEM41B scramblase to govern lipid partitioning and membrane homeostasis.

cell biology↗

Sparse, random sampling is sufficient for central tolerance

Negative selection in the thymus limits autoimmunity by eliminating T cells that react strongly to self. Individual T cells, however, are only exposed to a small fraction of all self peptides during their "training" in the thymus, and it is puzzling how tolerance can be generalized to the remaining "test" self peptides across peripheral tissues in the body. Using a machine learning perspective, we show that such generalization is possible because the immune system satisfies two conditions: first that peptide abundance levels in the human thymus and periphery are highly correlated (i.e., training distribution {approx} test distribution), and second that cross-reactivity allows T cells to effectively learn binding information of similar peptides without explicitly interacting with all of them. Together, we show that sparse, random sampling of only 10% of self peptides in the thymus is sufficient to avoid reactivity to 90% of peripheral self, and we support this result with diverse experimental data. We then validate two predictions by our model; the first is that only 200-250 antigen presenting cells need to be seen by a T cell to ensure its robust selection, and the second relates how peptides missing from the thymus can drive auto-immunity of peripheral tissues. Overall, we provide a plausible answer to a long-standing question underlying adaptive immunity, and we highlight how generalization, a fundamental challenge faced by nearly every learning algorithm, is uniquely tackled by the immune system.

immunology↗

AI recognizes convergent somatic hypermutation signatures to allow the discovery of variant-resilient broadly neutralizing antibodies

Elucidating the mechanisms by which broadly neutralizing antibodies (bnAbs) develop to confer durable immunity in humans is pivotal for the rational design of next-generation vaccines and therapeutics. VH3-53/3-66-encoded public antibodies are widely elicited in the population after the COVID-19 pandemic. Here, we isolated 15 VH3-53/3-66-encoded bnAbs from elite neutralizers who experienced sequential SARS-CoV-2 Omicron breakthrough infections. These bnAbs exhibit exceptional potency and breadth against circulating variants and, as members of a long-lived public antibody lineage, likely contribute to durable humoral protection. Genetic analysis of VH3-53/3-66-encoded bnAbs reveals a convergent somatic hypermutation pattern at seven positions in and around the CDR loops that emerges with repeated viral exposures and distinguishes them from non-bnAbs. Grafting these combined mutations onto clinically escaped antibodies broadens their breadth and restores neutralization activity. Structural analysis shows that these convergent mutations cooperatively remodel CDRs to bind and tolerate virus receptor-binding domain mutations. Using an AI-based antibody language model trained on data linking somatic hypermutations to binding affinity and neutralization, the model is able to identify mutational patterns predictive of breadth, enabling the discovery of a rare bnAb with protective activity against the latest variants from early-pandemic antibody repertoires. This demonstrates the feasibility of establishing an AI-empowered pipeline to identify mutation-tolerant bnAbs from early-pandemic antibody repertoires to fight fast-evolving newly introduced viruses.

immunology↗

LARIS enables accurate and efficient ligand and receptor interaction analysis in spatial transcriptomics

Advances in spatially resolved transcriptomics provide unprecedented opportunities to characterise intercellular communication pathways. However, robust and computationally efficient incorporation of spatial information into intercellular communication inference remains challenging. Here, we present LARIS (Ligand And Receptor Interaction analysis in Spatial transcriptomics), an accurate and scalable method that identifies cell type-specific and spatially restricted ligand-receptor (LR) interactions at single-cell or bead resolution. LARIS is compatible with all spatial transcriptomic technologies and quantifies specificity, infers sender-receiver directionality, and detects how differential interactions vary across time and space. To compare LARIS with existing methods, we established a simulation framework to generate ground truth of LR interactions with defined tissue architecture and gene expression patterns. LARIS demonstrates superior performances over other methods in accuracy and scalability. We further applied LARIS to human tonsil and developing mouse cortex spatial transcriptomics datasets collected from various spatial techniques. This uncovered the signalling mechanisms shaping tissue organisation and their changes over time. LARIS reveals cell type-, niche-, and condition-specific signalling and scales to hundreds of thousands of cells in minutes. This provides an efficient and direct method for discovering the molecular interplay between apposed cells across development.

bioinformatics↗

Developmental Trajectories of Addition and Subtraction in Early School-aged Children

Mastering basic arithmetic lays the foundation for lifelong mathematical achievement, yet how the neural mechanisms underlying addition and subtraction calculations develop during childhood remain unclear. This study investigated the developmental trajectories of addition and subtraction calculations in school-aged children, and explored how arithmetic-specific neural responses in the right parieto-occipital region are related to age-related improvements in behavioral performance. Here, we recorded electroencephalography (EEG) signals from 115 typically developing children divided into three age groups (7-8-, 9-10-, and 11-12-year-olds) during an arithmetic task involving addition and subtraction calculations. We analyzed the P300 component from the original waveforms and the {Delta}P300 component from the difference waveforms, which were generated by subtracting the event-related potentials (ERPs) elicited by the first operand from those elicited by the second operand to isolate arithmetic-specific neural processes. The results revealed that, in both calculations, older children showed better behavioral performance (faster reaction time and larger PI) and greater right parieto-occipital {Delta}P300 amplitudes, with a key developmental stage at 11-12 years. Furthermore, all groups of children exhibited greater right parieto-occipital P300 and {Delta}P300 amplitudes in subtraction, whereas the smaller right parieto-occipital {Delta}P300 amplitudes in addition significantly mediated the relationship between age and PI. These findings reveal distinct patterns for addition and subtraction calculations over development, highlighting the right parieto-occipital {Delta}P300 amplitude as a neural marker of arithmetic performance, particularly for addition calculation.

neuroscience↗

Optimal bioelectric control accelerates collective wound healing

Collective cell migration is critical in a range of biophysical processes spanning wound healing to tumor metastasis. It is therefore important to develop techniques for regulating cell motion, but while we have developed powerful migration tools from optogenetics and bioelectricity, the complex mechanics of collective systems make it difficult to determine where and when to apply these stimuli. For example, here we begin with a circular sheet of skin cells with a central hole, or "wound", and show that globally stimulating all cells to migrate radially inwards to close the gap through electrotaxis causes catastrophic mechanical damage, emerging from strong cell-cell adhesion, which we explain with an active elasticity model. We propose a solution inspired by sheepherding based on using local stimulation to learn the collective perturbation-response of the group and then drive tissue motion. First, we induce local electrotaxis to characterize the impulse-response function of quasi-1D strips of skin tissue, discovering that hyper-local stimulation triggers long-range tissue response over a length scale set by cell-cell adhesion also predicted by our model. Based on this, we apply local, concentric ring fields to in vitro circular wounds. Continuously driving cells towards the wound core kinetically traps the tissue in a jammed state and freezes healing. Pulsing the stimuli allows the tissue to relax and fluidize again, accelerating migration. Finally, we integrate the key length and timescales of tissue mechanics into a biophysically-informed continuum control model. The models predictive framework helps determine where and when to apply stimulation for optimal tissue growth which, when tested, accelerates healing 5-fold.

biophysics↗

METTL3-mediated SOCS3 m6A Modification in Preserving CD4+ T Cell Homeostasis in HIV Infected Long-term Non-progressors

The maintenance of normal CD4+ T cell levels in human immunodeficiency virus (HIV) infected long-term non-progressors (LTNPs) remains elusive. N6-methyladenosine (m6A) regulates RNA metabolism and immune function, but its role in LTNP pathogenesis is unelucidated. This study integrated in vivo analyses of peripheral blood mononuclear cells (PBMCs) from LTNPs, typical progressors (TPs), ART-treated patients, and healthy controls with in vitro experiments using the MT2-HIV-1B model to explored the m6A regulatory role in LTNPs. Methylated RNA immunoprecipitation sequencing (MeRIP-seq) identified uniquely elevated m6A modification abundance and METTL3 expression in LTNPs vs. TPs. Differential m6A and mRNA analysis bighlighted enrichment of innate immunity/inflammation pathways, particularly the SOCS/IL/JAK axis. Further experiments confirmed that METTL3 mediates m6A modification of SOCS3, which suppresses JAK2/STAT4 phosphorylation to modulate IL-12/IFN-{gamma}/IL-4 expression. These findings uncover a novel m6A-METTL3-SOCS3 regulatory axis underlying HIV long-term non-progression, explaining preserved CD4+ T cell homeostasis in LTNPs. IMPOTANCE LTNPs represent a unique subset of HIV-infected individuals who naturally maintain normal CD4 T cell levels and slow disease progression, offering a valuable model to dissect host protective mechanisms against HIV. mA modification has emerged as a pivotal regulator roles in HIV replication and T cell activation, yet its contribution to LTNP biology has remained unclear. This novel mechanism provides a potential explanation for the maintenance of normal CD4+ T cell levels in LTNPs. Our findings shed light on the molecular basis of HIV-1 long-term non-progression and offered crucial insights for developing functional cure for AIDS and new host immune strategies.

immunology↗

Patient-Specific Midbrain Organoids with CRISPR Correction Reveal Disease Mechanisms and Enable Therapeutic Evaluation in Neuronopathic Gaucher Disease

Neuronopathic Gaucher disease (nGD) is a lysosomal storage disorder caused by GBA1 mutations, leading to defective acid {beta}-glucosidase (GCase) and accumulation of glycosphingolipid substrates, causing inflammation and neurodegeneration. Patients with nGD manifest severe neurological symptoms, but current animal models fail to fully recapitulate human condition, posing a major barrier to the development of effective therapies targeting the brain. To bridge this gap, we have developed midbrain-like organoids (MLOs) from human induced pluripotent stem cells (hiPSCs) of nGD patients with GBA1L444P/P415R and GBA1L444P/RecNcil mutations to model nGD brain pathogenesis. These nGD MLOs exhibited GCase deficiency, resulting in diminished enzymatic function, accumulation of lipid substrates, widespread transcriptomic changes, and impaired dopaminergic neuron differentiation, mirroring nGD pathology. GBA1 mutation correction mediated by CRISPR/Cas9 restored GCase activity, normalized lipid substrate levels, and rescued dopaminergic neuron function, confirming the causal role of GBA1 mutations during early brain development. Using this novel platform, we further evaluated therapeutic strategies, including SapC-DOPS nanovesicles delivering GCase, AAV9-GBA1 gene therapy, and substrate reduction therapy with GZ452, a glucosylceramide synthase inhibitor currently under clinical investigation. These treatments either restored GCase activity, reduced lipid substrate accumulation, improved autophagic and lysosomal abnormalities, or ameliorated dysregulated genes involved in neural development. These patient-specific, 3D neural models offer a transformative, physiologically relevant platform for unravelling disease mechanisms and accelerating the discovery of therapies for patients with nGD.

neuroscience↗

Ultra-High Field 31P functional Magnetic Resonance Spectroscopy Reveals NAD+ Dynamics in Brain Energy Metabolism during Visual Stimulation.

We investigated dynamic changes in nicotinamide adenine dinucleotide (NAD{square}) metabolism in the human occipital lobe using ultra-high field 31P functional magnetic resonance spectroscopy (fMRS) at 7 Tesla. Twenty-five healthy volunteers (mean age 24 {+/-} 4 years, 10 female) performed a visual task alternating between fixation and flashing checkerboard stimuli. 31P MRS spectra were acquired from a visual cortex voxel functionally localized by prior fMRI. Linear mixed-effects modelling revealed a significant reduction in NAD{square} concentrations during the first stimulation block, while no significant change was observed during the second block. No significant changes were observed for other high-energy phosphate metabolites (ATP, phosphocreatine, and inorganic phosphate), indicating specificity in the NAD{square} response. Exploratory analyses, dividing the blocks in two halves, suggested further reductions in NAD{square} and tNAD in the second halves of both stimulation blocks, though these trends were not statistically significant. Our findings demonstrate the feasibility of using fMRS at 7T to detect stimulus-induced dynamics in cerebral NAD{square} metabolism in vivo, providing insights into the interplay between glycolysis and oxidative phosphorylation during neural activation.

neuroscience↗

Signaling bias of the protease-activated receptor-1 is dictated by distinct GRK5 and β-arrestin-2 determinants

G protein-coupled receptors (GPCRs) exhibit signaling bias, or preferential activation of heterotrimeric G proteins versus GPCR receptor kinase (GRK)-mediated {beta}-arrestin signaling. The protease-activated receptor-1 (PAR1) GPCR activates both G protein and {beta}-arrestin in response to thrombin, but only {beta}-arrestin in response to activated protein C (APC). Thrombin-activated PAR1-G protein signaling is desensitized by {beta}-arrestin-1, whereas APC-activated PAR1 signaling is propagated by {beta}-arrestin-2. The mechanisms underlying PAR1 biased signaling are not known. Here, using computational modeling and cell biology studies, we reveal the molecular basis of signaling by thrombin- and APC-activated PAR1. Although both thrombin- and APC-induced PAR1 signaling are regulated by the same GRK isoform, GRK5, the two types of signaling are differentially dependent on GRK5 membrane anchoring, PAR1 C-terminal phosphorylation, and the binding mode of {beta}-arrestin-2. These differences translate into distinct {beta}-arrestin-2 conformations and define the cytoprotective signaling signature by APC which contrasts with thrombin inflammatory signaling.

cell biology↗