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Biology subjects

Guo, P.

Publications and source records attributed to Guo, P..

At least 37 records · Page 2Linked to original sources

Enhancing protein graph representations through static-dynamic fusion

Machine learning for protein modeling faces significant challenges due to proteins inherently dynamic nature, yet most graph-based machine learning methods rely solely on static structural information. Recently, the growing availability of molecular dynamics trajectories provides new opportunities for understanding the dynamic behavior of proteins; however, computational methods for utilizing this dynamic information remain limited. We propose a novel graph representation that integrates both static structural information and dynamic correlations from molecular dynamics trajectories, enabling more comprehensive modeling of proteins. By applying relational graph neural networks (RGNNs) to process this heterogeneous representation, we demonstrate significant improvements over structure-based approaches across three distinct tasks: atomic adaptability prediction, binding site detection, and binding affinity prediction. Our results validate that combining static and dynamic information provides complementary signals for understanding proteinligand interactions, offering new possibilities for drug design and structural biology applications.

bioinformatics↗

Secreted cytokines from inflammatory macrophages modulate sex differences in valvular interstitial cells on hydrogel biomaterials

Patients with aortic valve stenosis (AVS) experience fibrosis and/or calcification in valve tissue, which leads to heart failure if left untreated. Inflammation is a hallmark of AVS and secreted cytokines from pro-inflammatory macrophages are thought to contribute to valve fibro-calcification by driving the activation of valvular interstitial cells (VICs) to myofibroblasts. However, the molecular mechanisms by which inflammatory cytokines differentially regulate myofibroblast activation as a function of biological sex are not fully defined. Here, we developed an in vitro hydrogel culture platform to culture male and female valvular interstitial cells (VICs) and characterize the sex-specific effects of inflammatory cytokines on VIC activation to myofibroblasts and osteoblast-like cells. Our data reveal that tumor necrosis factor alpha (TNF-) modulates female-specific myofibroblast activation via MAPK/ERK signaling, nuclear chromatin availability, and osteoblast-like differentiation via RUNX2 nuclear localization. Collectively, hydrogel biomaterials as cell culture platforms are critical for distinguishing sex differences in cellular phenotypes.

bioengineering↗

Determining sex differences in drug combinations targeting aortic valve myofibroblast activation using an artificial intelligence derived platform

Aortic valve stenosis (AVS) is a sexually dimorphic disease where aortic valve leaflets develop fibrosis and calcification, leading to heart failure if untreated. Sex differences in AVS progression depend on valvular interstitial cells (VICs) activating to myofibroblasts that drive aberrant extracellular matrix remodeling. To date, no treatment strategies have leveraged cellular sex differences to determine drug combinations that effectively target VIC myofibroblast activation. Here, we harnessed IDentif.AI, an artificial intelligence (AI)-derived drug optimization platform, to optimize sex-specific synergistic drug combinations that may prevent and reverse VIC myofibroblast activation on hydrogel biomaterials. The results reveal that anti-fibrotic drug efficacy and combinatorial interactions are dependent on cell sex. This study provides a framework for developing clinically relevant AVS treatment strategies through the integration of high-throughput hydrogel cell culture platforms and AI-driven drug optimization. The workflow towards designing targeted AVS drug combinations may help accelerate AVS drug development for male and female patients and address health disparities in AVS treatment outcomes.

bioengineering↗

Multiplexed spatial mapping of chromatin features, transcriptome, and proteins in tissues

The phenotypic and functional states of a cell are modulated by a complex interactive molecular hierarchy of multiple omics layers, involving the genome, epigenome, transcriptome, proteome, and metabolome. Spatial omics approaches have enabled the capture of information from different molecular layers directly in the tissue context. However, current technologies are limited to map one to two modalities at the same time, providing an incomplete representation of cellular identity. Such data is inadequate to fully understand complex biological systems and their underlying regulatory mechanisms. Here we present spatial-Mux-seq, a multi-modal spatial technology that allows simultaneous profiling of five different modalities, including genome-wide profiles of two histone modifications and open chromatin, whole transcriptome, and a panel of proteins at tissue scale and cellular level in a spatially resolved manner. We applied this technology to generate multi-modal tissue maps in mouse embryos and mouse brains, which discriminated more cell types and states than unimodal data. We investigated the spatiotemporal relationship between histone modifications, chromatin accessibility, gene and protein expression in neuron differentiation revealing the relationship between tissue organization, function, and gene regulatory networks. We were able to identify a radial glia spatial niche and revealed spatially changing gradient of epigenetic signals in this region. Moreover, we revealed previously unappreciated involvement of repressive histone marks in the mouse hippocampus. Collectively, the spatial multi-omics approach heralds a new era for characterizing tissue and cellular heterogeneity that single modality studies alone could not reveal.

genetics↗

Ultra-resolution Deconvolution of Spatial Transcriptomics Unveils Spatiotemporal Cellular Dynamics in Complex Microenvironments

Immune cells infiltrate tissues in response to exogenous pathogens or spontaneous tumors, generating protective immunity to safeguard tissues. Despite advancements in spatial transcriptomics (ST), the precise spatial distribution and functional specialization of immune cells within tissue microenvironments remain elusive. Here, we introduce an ultra-precision ST deconvolution algorithm (UCASpatial) that enhances the mapping of cell subpopulations to spatial locations by leveraging the contribution of genes indicative of cell identity through entropy-based weighting. Using both in silico and real ST datasets, we demonstrate that UCASpatial improves the robustness and accuracy in identifying low-abundant cell subpopulations and distinguishing transcriptionally heterogeneous cell subpopulations. Applying UCASpatial to human colorectal cancer (CRC), we link genomic alterations in individual cancer clones to multi-cellular characteristics of the tumor immune microenvironment (TIME) and reveal the co-evolution of tumor cells and TIME at a clonal resolution. We show that the copy number gain on chromosome 20q (chr20q-gain) in tumor cells orchestrates a T cell-excluded TIME, indicative of resistance to immunotherapy in CRC, and is associated with tumor-intrinsic human endogenous retrovirus subfamily H (HERV-H) silencing and impaired type I interferon response. In murine wound healing models, we illuminate the spatiotemporal dynamics of individual cell subsets across various stages of the healing process. We discovered that the scarring-healing mice (C57BL/6) exhibited a replacement of Prg4+ chondrogenic progenitors to Igfbp5+ chondrocytes in the wound bed at the regeneration stage, a change not observed in the regenerative strain (MRL/MpJ). The Igfbp5+ chondrocyte, spatially coordinating with Cd36+ Gpnmb+ Il1b- macrophage and Fmod+ fibroblast, forms a pro-fibrotic community associated with regeneration failure. The cell-cell interactions within this three-cell cluster, mediated by the IL11-IL11RA axis, drive the pro-fibrotic community formation and limit regeneration in C57BL/6 mice. Our findings present UCASpatial as a versatile tool for deciphering fine-grained cellular landscapes in ST and exploring intercellular mechanisms in complex and dynamic microenvironments.

bioinformatics↗

Y chromosome linked UTY modulates sex differences in valvular fibroblast methylation in response to nanoscale extracellular matrix cues

Aortic valve stenosis (AVS) is a progressive disease wherein males more often develop valve calcification relative to females that develop valve fibrosis. Valvular interstitial cells (VICs) aberrantly activate to myofibroblasts during AVS, driving the fibrotic valve phenotype in females. Myofibroblasts further differentiate into osteoblast-like cells and produce calcium nanoparticles, driving valve calcification in males. We hypothesized the lysine demethylase UTY (ubiquitously transcribed tetratricopeptide repeat containing, Y-linked) decreases methylation uniquely in male VICs responding to nanoscale extracellular matrix cues to promote an osteoblast-like cell phenotype. Here, we describe a hydrogel biomaterial cell culture platform to interrogate how nanoscale cues modulate sex-specific methylation states in VICs activating to myofibroblasts and osteoblast-like cells. We found UTY modulates the osteoblast-like cell phenotype in response to nanoscale cues uniquely in male VICs. Overall, we reveal a novel role of UTY in the regulation of calcification processes in males during AVS progression.

bioengineering↗

Combined Partial-Nitrification and Phosphorus Removal with the co-existence of Nitrite-resistant phosphorous accumulating organisms (PAOs) and nitrifiers in the treatment of high-strength manure digestate

Concurrent biological phosphorus (P) recovery and nitrogen (N) removal in treating high-strength wastewater (such as anaerobic digestate) has been considered incompatible due to presumed conflicts in the conflicting optimum conditions required by phosphorous accumulating organisms (PAO) and nitrifiers. However, this study achieved a stable nitrite accumulation while still maintained PAO activities in one sequencing batch reactor for treating the manure digestate under two aeration schemes (continuous versus intermittent aeration). Nitrite accumulated up to 80.5 {+/-} 21.1 mg-N/L under continuous aeration (6 h) mode. Switching to intermittent aeration (equivalent to 3 h) halved nitrite accumulation but increased total nitrogen removal efficiency from 53.5 {+/-} 12.2% to 84.7 {+/-} 9.4%. Mass balance analysis indicates that nearly all ammonia was removed as N2O. Both Enhanced Biological Phosphorus Removal (EBPR) activity assessment and phenotypic trait detection via single cell Raman spectrum (SCRS) confirmed the existence of yet to be identified PAOs that are resistant to high nitrite inhibition in our system. Visual Minteq calculation indicates that high concentrations of Ca in manure digestate may form precipitates and influence the bioavailability of P forms. Therefore, both biotic and abiotic pathways lead to a total P removal rate around 61.0 {+/-} 6.8%. This study highlights new opportunities to combine short-cut nitrogen removal via partial nitrification, nitrous oxide (N2O) collection, and EBPR in commercial farm-collected digested manure wastewater. Higher N and P removal efficiency could potentially be achieved by tuning aeration schemes in combination with down-stream anammox process. SynopsisConcurrent partial nitrification, N2O accumulation, and EBPR activity were found, leading to the exploration of novel nitrite-resistant PAOs, simultaneously N/P recovery, and waste-energy conversion in treating high strength wastewater.

microbiology↗

Mapping of multiple neurotransmitter receptor subtypes and distinct protein complexes to the connectome

Neurons express different combinations of neurotransmitter receptor (NR) subunits and receive inputs from multiple neuron types expressing different neurotransmitters. Localizing NR subunits to specific synaptic inputs has been challenging. Here we use epitope tagged endogenous NR subunits, expansion light-sheet microscopy, and EM connectomics to molecularly characterize synapses in Drosophila. We show that in directionally selective motion sensitive neurons, different multiple NRs elaborated a highly stereotyped molecular topography with NR localized to specific domains receiving cell-type specific inputs. Developmental studies suggested that NRs or complexes of them with other membrane proteins determines patterns of synaptic inputs. In support of this model, we identify a transmembrane protein associated selectively with a subset of spatially restricted synapses and demonstrate through genetic analysis its requirement for synapse formation. We propose that mechanisms which regulate the precise spatial distribution of NRs provide a molecular cartography specifying the patterns of synaptic connections onto dendrites.

neuroscience↗

RFC1 AAGGG pentanucleotide repeats form parallel G-quadruplex: structural implications for aberrant molecular cascades in CANVAS

A pentanucleotide repeat expansion (PRE) of (AAGGG)n in the replication factor C subunit 1 (RFC1) gene is recently identified as the genetic cause of cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS), and also linked to several other neurodegenerative disorders including the Parkinsons disease. However, the molecular mechanism by which RFC1 PRE drives pathology remains poorly understood. Here, for the first time we discovered and determined the high-resolution structures of parallel G-quadruplex formed by AAGGG repeats within the pathogenic RFC1 PRE, revealing an intriguing conformational plasticity at the 3-termi that allows stacking of multiple G4s. We further identify a molecular mechanism by which the DNA G4 in RFC1 PRE impedes polymerase processivity leading to replication stalling and transcription inhibition in vitro in a repeat-length-dependent manner, and the transcription inhibition could partially contribute to a reduced gene expression in cells. Our results demonstrate that the DNA G-quadruplex of RFC1 PRE participate in aberrant molecular cascades, and provide an unprecedented high-resolution structural target to discover helicases and ligands that resolve the pathogenic G4 for therapeutic intervention.

biochemistry↗

Spatial transcriptomic atlas of shoot organogenesis in tomato callus

Callus is a reprogrammed transitional cell mass during plant regeneration. Pluripotent callus cells develop into fertile shoots through de novo shoot organogenesis. This study represents a pioneering effort in exploring the spatial transcriptome of tomato callus during shoot regeneration, using technologies including BGI Stereo-seq, BMKMANU S1000, and 10x Visium. The results indicate that the callus comprises highly heterogeneous cells, classified into various cell types based on spatial gene expression and histological observation, including epidermis, shoot primordium, vascular tissue, inner callus, and outgrowth shoots. The developmental trajectories from shoot primordium to outgrowth shoot are traced, and vascular tissue development is characterized. The single-cell resolution spatial approach reveals the origin of shoot primordia from the sub-epidermis. The spatial full length RNA sequencing shows high incompletely spliced (IS) ratios in the shoot primordium cells. These findings enhance our knowledge of plant organogenesis and highlight the significance of spatial biology in plant research.

cell biology↗

A Methylation-Phosphorylation Switch Controls EZH2 Stability and Hematopoiesis

The Polycomb Repressive Complex 2 (PRC2) methylates H3K27 to regulate development and cell fate by transcriptional silencing. Alteration of PRC2 is associated with various cancers. Here, we show that mouse Lsd1/Kdm1a deletion causes dramatic reduction of PRC2 proteins, whereas mouse null mutation of L3mbtl3 or Dcaf5 results in PRC2 accumulation and increased H3K27 trimethylation. The catalytic subunit of PRC2, EZH2, is mono-methylated at lysine 20 (K20), promoting EZH2 proteolysis by L3MBTL3 and the CLR4DCAF5 ubiquitin ligase. LSD1 demethylates the methylated K20 to stabilize EZH2. K20 methylation is inhibited by AKT-mediated phosphorylation of serine 21 in EZH2. Mouse K20R mutants develop hepatosplenomegaly associated with high GFI1B expression, and K20R mutant bone marrows expand hematopoietic stem cells and downstream hematopoietic populations. Our studies reveal that EZH2 is regulated by methylation dependent proteolysis, which is negatively controlled by AKT-mediated S21 phosphorylation to establish a methylation-phosphorylation switch to control the PRC2 activity and hematopoiesis.

biochemistry↗

Rapid Development of a Mucosal Nanoparticle Flu Vaccine by Genetic Engineering of Bacteriophage T4 using CRISPR-Cas

Mucosal vaccines that can induce local mucosal immune responses and combat the pathogens at entry sites are considered to be the most effective way to prevent infection. A universal platform that can be customized for development of mucosal vaccines against any given pathogen is therefore highly desired. Here, we demonstrate an efficient approach to develop nasal mucosal vaccines through genetic engineering of T4 phage to generate antigen-decorated nanoparticles. The antigen coding sequence was inserted into T4 genome in-frame at the C terminus of Soc (small outer capsid protein) using the CRISPR-Cas phage editing technology. During the propagation of recombinant T4 phages in E. coli, the Soc-antigen fusion proteins self-assemble on T4 capsids to form antigen-decorated nanoparticles that have intrinsic adjuvant activity and mucosal adhesive property. As a proof of concept, we showed that intranasal immunization with Flu viral M2e-decorated T4 nanoparticles efficiently induced local mucosal as well as systemic immune responses and provided complete protections against divergent influenza viruses in a mouse model. Potentially, our platform can be customized for any respiratory pathogen to rapidly generate mucosal vaccines against future emerging epidemics and pandemics.

immunology↗

Cadmium is detrimental to Caenorhabditis elegans via anetwork involving circRNA, lncRNA and phosphorylatedprotein

Cadmium (Cd) as a heavy metal causes serious environmental pollution and multiple organ and system damage in human. However, little is known about the specific molecular mechanisms of the associated regulatory networks. In this study, we selected Caenorhabditis elegans (C. elegans) to investigate the effects of Cd exposure as it acts as an acknowledged and established genetic model organism. A total of 26 differentially-expressed circular RNA (DEcircRNAs), 143 lncRNAs (DElncRNAs), 69 microRNAs (DEmiRNAs) and 6209 mRNAs (DEmRNAs) were found and identified, which might influence reproductive function, aging processes and nervous system functions through regulating the levels of circRNAs and lncRNAs and the controlling of regulatory networks of circRNA/lncRNA-miRNA-mRNA. Based on quantitative PCR, four DEcircRNAs and three DElncRNAs were confirmed to have different expression levels between the Cd-treated and control group. Further, 5 protein-coding genes might be regulated by DElnRNAs through cis-acting and 114 by trans-acting elements. Additionally, 42 differentially regulative phosphopeptides were detected and 4 novel pairs of transcription factors (TFs)-kinase-substrate that might be influenced by Cd exposure were constructed by phosphoproteomics. Our findings suggest that Cd might influence multi-functions and the aging process of C. elegans and may inhibit the expression of TFs to reduce phosphorylated levels of the corresponding protein. SynopsisCadmium exists widely in soil, water and air. This study manifested the regulatory network involving circRNA, lncRNA and phosphorylated protein in C.elegans after Cd exposure, which revealing the potential molecular mechanism underlying the toxic effect caused by Cd. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=82 SRC="FIGDIR/small/486470v1_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@1a012bborg.highwire.dtl.DTLVardef@2dc128org.highwire.dtl.DTLVardef@1e43ebaorg.highwire.dtl.DTLVardef@1d236b8_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

Self-avoidance alone does not explain the function of Dscam1 in mushroom body axonal wiring

Alternative splicing of Drosophila Dscam1 into 38,016 isoforms provides neurons with a unique molecular code for self-recognition and self-avoidance. A canonical model suggests that homophilic binding of identical Dscam1 isoforms on sister branches of mushroom body (MB) axons supports segregation with high fidelity, even when only a single isoform is expressed. Here we generated a series of mutant flies with a single exon 4, 6, or 9 variant, encoding 1,584, 396, or 576 potential isoforms, respectively. Surprisingly, most of the mutants in the latter two groups exhibited obvious defects in the growth, branching, and segregation of MB axonal sister branches. This demonstrates that repertoires of 396 and 576 Dscam1 isoforms were not sufficient for normal patterning of axonal branches. Moreover, reducing Dscam1 levels largely reversed the defects caused by reduced isoform diversity, suggesting a functional link between Dscam1 expression levels and isoform diversity. Taken together, these results indicate that canonical self-avoidance alone does not explain the function of Dscam1 in MB axonal wiring.

neuroscience↗

Cis mutagenesis in vivo reveals extensive noncanonical functions of Dscam1 isoforms in neuronal wiring

Drosophila Dscam1 encodes ten thousand of cell recognition molecules via alternative splicing, which is required for nervous function. However, the underlying mechanism has not fully understood. Here we revealed extensive noncanonical functions of Dscam1 isoform diversity in neuronal wiring. We generated a series of allelic cis mutations in Dscam1, encoding normal number of isoforms albeit with altered isoform composition. Despite normal dendritic self-avoidance and self/non-self discrimination in da neurons, which is consistent with canonical self-avoidance model, these mutants exhibited strikingly distinct spectra of phenotypic defects in three classes of neurons: up to [~]60% defects in mushroom bodies, a significantly increased branching and growth in da neurons, and mild axonal branching defects in mechanosensory neurons. These data suggest that proper Dscam1 isoform composition is required for axon and dendrite growth in diverse neurons. This unprecedented splicing-tuned regulation unlocks new insights into the molecular mechanisms that Dscam1 isoform diversity is engaged in.

neuroscience↗

Cell transcriptomic atlas of the non-human primate Macaca fascicularis

Studying tissue composition and function in non-human primates (NHP) is crucial to understand the nature of our own species. Here, we present a large-scale single-cell and single-nucleus transcriptomic atlas encompassing over one million cells from 43 tissues from the adult NHP Macaca fascicularis. This dataset provides a vast, carefully annotated, resource to study a species phylogenetically close to humans. As proof of principle, we have reconstructed the cell-cell interaction networks driving Wnt signalling across the body, mapped the distribution of receptors and co-receptors for viruses causing human infectious diseases and intersected our data with human genetic disease orthologous coordinates to identify both expected and unexpected associations. Our Macaca fascicularis cell atlas constitutes an essential reference for future single-cell studies in human and NHP.

cell biology↗

Cx43 carboxyl terminal domain determines AQP4 and Cx30 endfoot organization and blood brain barrier permeability

The neurovascular unit (NVU) consists of cells intrinsic to the vessel wall, the endothelial cells and pericytes, and astrocyte endfeet that surround the vessel but are separated from it by basement membrane. Endothelial cells are primarily responsible for creating and maintaining blood-brain-barrier (BBB) tightness, but astrocytes contribute to the barrier through paracrine signaling to the endothelial cells and by forming the glia limitans. Gap junctions (GJs) between astrocyte endfeet are composed of connexin 43 (Cx43) and Cx30, which form plaques between cells. GJ plaques formed of Cx43 do not diffuse laterally in the plasma membrane and thus potentially provide stable organizational features to the endfoot domain, whereas GJ plaques formed of other connexins and of Cx43 lacking a large portion of its cytoplasmic carboxyl terminus are quite mobile. In order to examine the organizational features that immobile GJs impose on the endfoot, we have used super-resolution confocal microscopy to map number and sizes of GJ plaques and aquaporin (AQP)-4 channel clusters in the perivascular endfeet of mice in which astrocyte GJs (Cx30, Cx43) were deleted or the carboxyl terminus of Cx43 was truncated. To determine if blood-brain-barrier integrity was compromised in these transgenic mice, we conducted perfusion studies under elevated hydrostatic pressure using horseradish peroxide as a molecular probe enabling detection of micro-hemorrhages in brain sections. These studies revealed that microhemorrhages were more numerous in mice lacking Cx43 or its carboxyl terminus. In perivascular domains of cerebral vessels, we found that density of Cx43 GJs was higher in the truncation mutant, while GJ size was smaller. Density of perivascular particles formed by AQP4 and its extended isoform AQP4ex was inversely related to the presence of full length Cx43, whereas the ratio of sizes of the particles of the AQP4ex isoform to total AQP4 was directly related to the presence of full length Cx43. Confocal analysis showed that Cx43 and Cx30 were substantially colocalized in astrocyte domains near vasculature of truncation mutant mice. These results showing altered distribution of some astrocyte nexus components (AQP4 and Cx30) in Cx43 null mice and in a truncation mutant, together with leakier cerebral vasculature, support the hypothesis that localization and mobility of gap junction proteins and their binding partners influences organization of astrocyte endfeet which in turn impacts BBB integrity of the NVU.

neuroscience↗

Bacteriophage T4 Vaccine Platform for Next-generation Influenza Vaccine Development

Developing influenza vaccines that protect against a broad range of viruses is a public health priority, and several conserved viral proteins or domains have been identified as promising targets for such vaccine development. However, none of the targets is immunogenic, and vaccine platforms that can incorporate multiple antigens with enhanced immunogenicity are desperately needed. In this study, we provided proof-of-concept for the development of next-generation influenza vaccine using T4 phage virus-like particle (VLP) platform. With extracellular domain of influenza matrix protein 2 (M2e) as a readout, we showed that more than 1,280 M2e molecules can be assembled on a 120x90 nanometer phage capsid to form T4-M2e VLPs, which are highly immunogenic and induced complete protection against influenza virus challenge without any addition adjuvant. Potentially, additional conserved antigens or molecular adjuvants could be incorporated into the T4-M2e VLPs to customize influenza vaccines to address different issues. All the components of T4 VLP vaccines can be mass-produced in E. coli in a short time, therefore, providing a rapid approach to deal with the potential influenza pandemic.

microbiology↗