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Sun, J.

Publications and source records attributed to Sun, J..

At least 271 records · Page 15Linked to original sources

Predicting Gene Spatial Expression and Cancer Prognosis: An Integrated Graph and Image Deep Learning Approach Based on HE Slides

Interpreting the tumor microenvironment (TME) heterogeneity within solid tumors presents a cornerstone for precise disease diagnosis and prognosis. However, while spatial transcriptomics offers a wealth of data, ranging from gene expression and spatial location to corresponding Hematoxylin and Eosin (HE) images, to explore the TME of various cancers, its high cost and demanding infrastructural needs significantly limit its clinical application, highlighting the need for more accessible alternatives. To bridge this gap, we introduce the Integrated Graph and Image Deep Learning (IGI-DL) model. This innovation, a fusion of Convolutional Neural Networks and Graph Neural Networks, is designed to predict gene spatial expression using HE images. The IGI-DL model outperforms its predecessors in analyzing colorectal cancer (CRC), breast cancer, and cutaneous squamous cell carcinoma (cSCC) by leveraging both pixel intensity and structural features in images. Significantly, across all cancer types, the IGI-DL model enhances the mean correlation of the top five genes by an average of 0.125 in internal and external test sets, rising from 0.306 to 0.431, surpassing existing state-of-the-art (SOTA) models. We further present a novel risk score derived from a super-patch graph, where gene expression predicted by IGI-DL serves as node features. Demonstrating superior prognostic accuracy, this risk score, with a C-index of 0.713 and 0.741 for CRC and breast cancer, supersedes traditional HE-based risk scores. In summary, the approach augments our understanding of the TME from the aspect of histological images, portending a transformation in cancer prognostics and treatment planning and ushering in a new era of personalized and precision oncology.

bioinformatics↗

Quasi-Equilibrium State Based Quantification of Biological Macromolecules in Single-Molecule Localization Microscopy

The stoichiometry of molecular components within supramolecular biological complexes is often an important property to understand their biological functioning, particularly within their native environment. While there are well established methods to determine stoichiometry in vitro, it is presently challenging to precisely quantify this property in vivo, especially with single molecule resolution that is needed for the characterization stoichiometry heterogeneity. Previous work has shown that optical microscopy can provide some information to this end, but it can be challenging to obtain highly precise measurements at higher densities of fluorophores. Here we provide a simple approach using already established procedures in single-molecule localization microscopy (SMLM) to enable precise quantification of stoichiometry within individual complexes regardless of the density of fluorophores. We show that by focusing on the number of fluorophore detections accumulated during the quasi equilibrium-state of this process, this method yields a 50-fold improvement in precision over values obtained from images with higher densities of active fluorophores. Further, we show that our method yields more correct estimates of stoichiometry with nuclear pore complexes and is easily adaptable to quantify the DNA content with nanodomains of chromatin within individual chromosomes inside cells. Thus, we envision that this straightforward method may become a common approach by which SMLM can be routinely employed for the accurate quantification of subunit stoichiometry within individual complexes within cells.

biophysics↗

Differential cellular immune responses against Orientia tsutsugamushi Karp and Gilliam strains following acute infection in mice

Scrub typhus is the leading source of febrile illness in endemic countries due to infection with Orientia tsutsugamushi (Ot), a seriously understudied intracellular bacterium. Pulmonary complications in patients are common and can develop into life threatening conditions. The diverse antigenicity of Ot genotypes and inter-strain differences seem to be connected to varied virulence and clinical outcomes; however, detailed studies of strain-related pulmonary immune responses in human patients or experimental animals are lacking. In this study, we used two clinically prevalent bacterial strains, Karp and Gilliam, and revealed cellular immune responses in inflamed lungs and potential biomarkers of disease severity. We found that outbred CD-1 mice were highly susceptible to both Karp and Gilliam strains; however, C57BL/6 (B6) mice were susceptible to Karp, but resistant to Gilliam (with self-limiting infection), corresponding to their tissue bacterial burdens and lung pathological changes. Multicolor flow cytometric analyses of perfused B6 mouse lungs revealed robust and sustained influx and activation of innate immune cells (monocytes, macrophages, neutrophils, and NK cells), followed by those of CD4+ and CD8+ T cells, during Karp infection, but such responses were greatly attenuated during Gilliam infection. The robust cellular responses in Karp-infected B6 mice were positively correlated with significantly early and high levels of serum cytokine/chemokine protein levels (CXCL1, CCL2/3/5, and G-CSF), as well as pulmonary gene expression (CXCL1/2, CCL2/3/4, and IFN{gamma}). In vitro infection of B6 mouse-derived primary macrophages also revealed bacterial strain-dependent immune gene expression profiles. This study provided the first lines of evidence that highlighted differential tissue cellular responses against Karp vs. Gilliam infection, offering a framework for future investigation of Ot strain-related mechanisms of disease pathogenesis vs. infection control. Authors SummaryOrientia tsutsugamushi (Ot) infection-induced scrub typhus is a leading cause of febrile illness in endemic countries. Research on Ot strain-related disease outcomes or immune signatures in tissue and blood samples is very limited. Using two clinically prevalent strains (Karp and Gilliam), we examined host susceptibility in inbred and outbred mouse models and provided new evidence for the activation of pulmonary immune cell subsets during the acute stages of infection. While Gilliam-infected C57BL/6 (B6) mice developed self-limiting infection, mild cellular responses, and tissue injury, Karp infection led to a strong and sustained activation of innate immune cells, followed by extensive influx of activated T cells, which correlated to protein levels of inflammatory cytokines/chemokines in serum samples. We also provided in vitro evidence for Ot strain-dependent immune gene profiles, indicating differential macrophage responses to Karp versus Gilliam bacteria. This is the first comparison of different scrub typhus mouse models with in-depth analyses of cellular responses in inflamed lungs, offering novel insights into potential mechanisms of disease progression versus infection control related to Ot strains and laying the foundation for future investigations.

immunology↗

High-throughput confocal airy beam oblique light-sheet tomography of brain-wide imaging at single-cell resolution

Brain research is an area of research characterized by its cutting-edge nature, with brain mapping constituting a crucial aspect of this field. As sequencing tools have played a crucial role in gene sequencing, brain mapping largely depends on automated, high-throughput and high-resolution imaging techniques. Over the years, the demand for high-throughput imaging has scaled exponentially with the rapid development of microscopic brain mapping. In this paper, we introduce the novel concept of confocal Airy beam into oblique light-sheet tomography named CAB-OLST. We demonstrate that this technique enables the high throughput of brain-wide imaging of long-distance axon projection for the entire mouse brain at a resolution of 0.26 m x 0.26 m x 1.06 m in 58 hours. This technique represents an innovative contribution to the field of brain research by setting a new standard for high-throughput imaging techniques.

neuroscience↗

A deep learning-based drug repurposing screening and validation for anti-SARS-CoV-2 compounds by targeting the cell entry mechanism

The recent outbreak of Corona Virus Disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been a severe threat to the global public health and economy, however, effective drugs to treat COVID-19 are still lacking. Here, we employ a deep learning-based drug repositioning strategy to systematically screen potential anti-SARS-CoV-2 drug candidates that target the cell entry mechanism of SARS-CoV-2 virus from 2,635 FDA-approved drugs and 1,062 active ingredients from Traditional Chinese Medicine herbs. In silico molecular docking analysis validates the interactions between the top compounds and host receptors or viral spike proteins. Using a SARS-CoV-2 pseudovirus system, we further identify several drug candidates including Fostamatinib, Linagliptin, Lysergol and Sophoridine that can effectively block the cell entry of SARS-CoV-2 variants into human lung cells even at a nanomolar scale. These efforts not only illuminate the feasibility of applying deep learning-based drug repositioning for antiviral agents by targeting a specified mechanism, but also provide a valuable resource of promising drug candidates or lead compounds to treat COVID-19.

microbiology↗

Covalent targeting as a common mechanism for inhibiting NLRP3 inflammasome assembly.

The NLRP3 inflammasome is a cytosolic protein complex important for the regulation and secretion of inflammatory cytokines including IL-1{beta} and IL-18. Aberrant overactivation of NLRP3 is implicated in numerous inflammatory disorders. However, the activation and regulation of NLRP3 inflammasome signaling remains poorly understood, limiting our ability to develop pharmacologic approaches to target this important inflammatory complex. Here, we developed and implemented a high-throughput screen to identify compounds that inhibit inflammasome assembly and activity. From this screen we identify and profile inflammasome inhibition of 20 new covalent compounds across 9 different chemical scaffolds, as well as many known inflammasome covalent inhibitors. Intriguingly, our results indicate that NLRP3 possesses numerous reactive cysteines on multiple domains whose covalent targeting blocks activation of this inflammatory complex. Specifically, focusing on compound VLX1570, which possesses multiple electrophilic moieties, we demonstrate that this compound allows covalent, intermolecular crosslinking of NLRP3 cysteines to inhibit inflammasome assembly. Our results, along with the recent identification of numerous covalent molecules that inhibit NLRP3 inflammasome activation, suggests that NLRP3 serves as a cellular electrophile sensor important for coordinating inflammatory signaling in response to redox stress. Further, our results support the potential for covalent cysteine modification of NLRP3 for regulating inflammasome activation and activity.

biochemistry↗

Spatio-temporal variation of bacterial community structure in two intertidal sediment types of Jiaozhou Bay

The intertidal sediment environment is dynamic and the biofilm bacterial community within it must constantly adjust, but an understanding of the differences in the biofilm bacterial community within sediments of different types is still relatively limited. In this study, the structure of the bacterial community in Jiaozhou Bay sediment biofilms are described using high-throughput 16S rRNA gene sequencing and the effects of temporal change and different sediment environment types are discussed. The Shannon index was significantly higher in sandy samples than in muddy samples. The co-occurrence network was tighter and more species were involved in community building in sandy samples. The principal coordinates analysis identified a significant separation between different sediment types and between stations (LiCun estuary, LC and ZhanQiao Pier, ZQ). Proteobacteria, which had a relative abundance of approximately 50% at all phylum levels, was significantly more abundant at ZQ, while Campilobacterota and Firmicutes were significantly more abundant at LC. The relative abundances of Bacteroidetes, Campilobacterota, Firmicutes, and Chloroflexi were significantly higher in the muddy samples, while Actinobacteria and Proteobacteria were higher in the sandy samples. There were different phylum-level biomarkers between sediment types at different stations. There were also different patterns of functional enrichment in biogeochemical cycles between sediment types and stations with the former having more gene families that differed significantly, highlighting their greater role in determining bacterial function. The RDA results, where each months samples were concentrated individually, showed reduced variation between months when the amplicon sequence variant was replaced by KEGG orthologs, presumably the temporal change had an impact on shaping the intertidal sediment bacterial community, although this was less clear at the gene family level. Random forest prediction yielded a combination of 43 family-level features that responded well to temporal change, reflecting the influence of temporal change on sediment biofilm bacteria. HighlightsO_LISandy sediments have more bacterial species involved in community building. C_LIO_LIDifferent substrates from different stations have their own phylum biomarkers. C_LIO_LISubstrates have a greater influence on shaping bacterial function. C_LIO_LITemporal changes have a greater shaping power on bacteria than on gene families. C_LI Graphic abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=121 SRC="FIGDIR/small/542048v1_ufig1.gif" ALT="Figure 1"> View larger version (43K): org.highwire.dtl.DTLVardef@1834e64org.highwire.dtl.DTLVardef@18fc695org.highwire.dtl.DTLVardef@369657org.highwire.dtl.DTLVardef@1c85a13_HPS_FORMAT_FIGEXP M_FIG C_FIG

ecology↗

Drosophila AHR limits tumor growth and stem cell proliferation in the intestine

The aryl hydrocarbon receptor (AHR) plays important roles in intestinal homeostasis, limiting tumour growth and promoting differentiation in the intestinal epithelium. Spineless, the Drosophila homolog of AHR, has only been studied in the context of development but not in the adult intestine. Here, we show that spineless is upregulated in the adult intestinal epithelium after infection with Pseudomonas entomophila (P.e.). Spineless knockdown increased stem cell proliferation following infection-induced injury. Spineless overexpression limited intestinal stem cell proliferation and reduced survival after infection. In two tumour models, using either Notch RNAi or constitutively active Yorkie, Spineless suppressed tumour growth and doubled the lifespan of tumour-bearing flies. At the transcriptional level it reversed the gene expression changes induced in Yorkie tumours, counteracting cell proliferation and altered metabolism. These findings demonstrate a new role for Spineless in the adult Drosophila midgut and highlight the evolutionarily conserved functions of AHR/Spineless in the control of proliferation and differentiation of the intestinal epithelium.

cancer biology↗

Deciphering molecular heterogeneity and dynamics of neural stem cells in human hippocampal development, aging, and injury

While accumulated publications support the existence of neurogenesis in the adult human hippocampus, the homeostasis and developmental potentials of neural stem cells (NSCs) under different contexts remain unclear. Based on our generated single-nucleus atlas of the human hippocampus across neonatal, adult, aging and injury, we dissected the molecular heterogeneity and transcriptional dynamics of human hippocampal NSCs under different contexts. We further identified new specific neurogenic lineage markers that overcome the lack of specificity found in some well-known markers. Based on developmental trajectory and molecular signatures, we found that a subset of NSCs exhibit quiescent properties after birth, and most NSCs become deep quiescence during aging. Furthermore, certain deep quiescent NSCs are re-activated following stroke injury. Together, our findings provide valuable insights into the development, aging, and re-activation of the human hippocampal NSCs, and help to explain why adult hippocampal neurogenesis is infrequently observed in humans.

neuroscience↗

A near-complete genome sequence of einkorn wheat provides insight into the evolution of wheat A subgenomes

Einkorn wheat (Triticum monococcum) is one of the oldest cereal crops to be domesticated by human beings, playing essential role in early agriculture development. Today, it is considered an important genomic resource for modern wheat improvement, especially for resistance against pests and diseases. However, the exploration and utilization of useful genes from T. monococcum is limited due to the lack of a reference genome and annotation for this species. Here, we report a near-complete genome assembly for T. monococcum with a total length of 5.11 Gb with a contig N50 of 131.2Mb and scaffold N50 of 728.66Mb, representing a genome assembly of highest quality for any wheat genome reported. Phylogenomic analysis confirmed T. monococcum is closely-related to T. urartu, the progenitor of wheat A subgenomes. A 4AL/5AL terminal translocation is present in the diploid species T. urartu and T. monococcum, taking place before wheat polyploidization. T. monococcum has significantly expanded and unique gene families involved in DNA damage repair and heat stress tolerance, reflecting its adaptive evolution to cope with historical harsh climate in its natural habitat, South East Turkey. The genome sequence confirmed the introgression of T. monococcum rust resistance genes at 5AmL into modern bread wheat varieties. This near-complete reference genome of T. monococcum will be an essential resource for wheat functional and evolutionary genomic studies and expedite the cloning of useful genes in T. monococcum for future wheat improvement.

genomics↗

Puromycin reveals a distinct conformation of neuronal ribosomes

Puromycin is covalently added to the nascent chain of proteins by the peptidyl transferase activity of the ribosome and the dissociation of the puromycylated peptide typically follows this event. It was postulated that blocking the translocation of the ribosome with emetine could retain the puromycylated peptide on the ribosome, but evidence against this has recently been published (Hobson et al., 2020 https://doi.org/10.7554/eLife.60048; Enam et al., 2020 https://doi.org/10.7554/eLife.60303). In neurons, puromycylated nascent chains remain in the ribosome even in the absence of emetine, yet direct evidence for this has been lacking. Using biochemistry and cryo-electron microscopy, we show that the puromycylated peptides remain in the ribosome exit channel in the large subunit in a subset of neuronal ribosomes stalled in the hybrid state. These results validate previous experiments to localize stalled polysomes in neurons and provide insight into how neuronal ribosomes are stalled. Moreover, in these hybrid-state neuronal ribosomes, anisomycin, which usually blocks puromycylation, competes poorly with puromycin in the puromycylation reaction, allowing a simple assay to determine the proportion of nascent chains that are stalled in this state. In early hippocampal neuronal cultures, over 50% of all nascent peptides are found in these stalled polysomes. These results provide new insights into the stalling mechanisms of neuronal ribosomes and suggest that puromycylated peptides can be used to reveal subcellular sites of hybrid-state stalled ribosomes in neurons. Significance StatementPuromycin can be covalently linked to the nascent polypeptide chain on ribosomes, followed by dissociation of the puromycylated polypeptide. Here, we conclusively show that in stalled ribosomes isolated from neuronal RNA granules, the puromycylated peptide remains in the polypeptide exit tunnel of the ribosome. This validates previous data using this technique to localize stalled ribosomes in neurons and suggests a unique ribosomal conformation in these cells. Further evidence for the unique state of these ribosomes is the resistance of puromycylation to the inhibitor anisomycin, which prevents puromycylation in all other cellular contexts. These results provide insight into the mechanism underlying neuronal ribosome stalling and resolve a controversy about using puromycin to localize ribosome stalling in neurons.

neuroscience↗

Single cell analyses of cancer cells identified two regulatorily and functionally distinct categories in differentially expressed genes among tumor subclones

To explore the feature of cancer cells and tumor subclones, we analyzed 101,065 single-cell transcriptomes from 12 colorectal cancer (CRC) patients and 92 single cell genomes from one of these patients. We found cancer cells, endothelial cells and stromal cells in tumor tissue expressed much more genes and had stronger cell-cell interactions than their counterparts in normal tissue. We identified copy number variations (CNVs) in each cancer cell and found correlation between gene copy number and expression level in cancer cells at single cell resolution. Analysis of tumor subclones inferred by CNVs showed accumulation of mutations in each tumor subclone along lineage trajectories. We found differentially expressed genes (DEGs) between tumor subclones had two populations: DEGCNV and DEGreg. DEGCNV, showing high CNV-expression correlation and whose expression differences depend on the differences of CNV level, enriched in housekeeping genes and cell adhesion associated genes. DEGreg, showing low CNV-expression correlation and mainly in low CNV variation regions and regions without CNVs, enriched in cytokine signaling genes. Furthermore, cell-cell communication analyses showed that DEGCNV tends to involve in cell-cell contact while DEGreg tends to involve in secreted signaling, which further support that DEGCNV and DEGreg are two regulatorily and functionally distinct categories.

genomics↗

Nuclear bodies protect phase separated proteins from degradation in stressed proteome

RNA-binding proteins (RBPs) containing intrinsically disordered domains undergo liquid-liquid phase separation to form nuclear bodies under stress conditions. This process is also connected to the misfolding and aggregation of RBPs, which are associated with a series of neurodegenerative diseases. However, it remains elusive how folding states of RBPs changes upon the formation and maturation of nuclear bodies. Here, we describe SNAP-tag based imaging methods to visualize the folding states of RBPs in live cells via time-resolved quantitative microscopic analyses of their micropolarity and microviscosity. Using these imaging methods in conjunction with immunofluorescence imaging, we demonstrate that RBPs, represented by TDP-43, initially enters the PML nuclear bodies in its native state upon transient proteostasis stress, albeit it begins to misfolded during prolonged stress. Furthermore, we show that heat shock protein 70 co-enters the PML nuclear bodies to prevent the degradation of TDP-43 from the proteotoxic stress, thus revealing a previously unappreciated protective role of the PML nuclear bodies in the prevention of stress-induced degradation of TDP-43. In summary, our imaging methods described in the manuscript, for the first time, reveal the folding states of RBPs, which were previously challenging to study with conventional methods in nuclear bodies of live cells. This study uncovers the mechanistic correlations between the folding states of a protein and functions of nuclear bodies, in particular PML bodies. We envision that the imaging methods can be generally applied to elucidating the structural aspects of other proteins that exhibit granular structures under biological stimulus.

biochemistry↗

A parabrachial-hypothalamic parallel circuit governs cold defense in mice

Thermal homeostasis is vital for mammals and is controlled by brain neurocircuits. Remarkable advances have been made in understanding how neurocircuits centered in the hypothalamic preoptic area (POA), the brains thermoregulation center, control warm defense, whereas mechanisms by which the POA regulates cold defense remain unclear. Here, we confirmed that the pathway from the lateral parabrachial nucleus (LPB) to the POA, is critical for cold defense. Parallel to this pathway, we uncovered that a pathway from the LPB to the dorsomedial hypothalamus (DMH), namely the LPB[->]DMH pathway, is also essential for cold defense. Projection-specific blockings revealed that both pathways provide an equivalent and cumulative contribution to cold defense, forming a parallel circuit. Specifically, activation of the LPB[->]DMH pathway induced strong cold-defense responses, including increases in thermogenesis of brown adipose tissue (BAT), muscle shivering, heart rate, and physical activity. Further, we identified a subpopulation of somatostatin+ neurons in the LPB that target the DMH to promote BAT thermogenesis. Therefore, we reveal a parabrachial-hypothalamic parallel circuit in governing cold defense in mice. This not only enables resilience to hypothermia but also provides a scalable and robust network in heat production, reshaping our understanding of how neural circuits regulate essential homeostatic behaviors.

neuroscience↗

Sterile Soil as Prebiotics Mitigate Intergenerational Loss of Gut Microbial Diversity and Anxiety-Like Behavior Induced by Antibiotics in mice

The decline in gut microbial diversity of modern human is closely associated with the rising prevalence of various diseases. It is imperative to investigate the underlying causes of gut microbial loss and the rescue measures. Although the impact of non-perinatal antibiotic use on gut microbiota has been recognized, its intergenerational effects remain unexplored. Our previous research has highlighted soil in the farm environment as a key prebiotic for gut microbiome health by restoring gut microbial diversity and balance. In this study, we investigated the intergenerational consequences of antibiotic exposure and the therapeutic potential of soil prebiotics. We treated mice with vancomycin and streptomycin for 2 weeks continuously, followed by 4-8 weeks of withdrawal period before breeding. The process was repeated across 3 generations. Half of the mice in each generation received an oral soil prebiotic intervention. We assessed gut microbial diversity, anxiety behavior, microglia reactivity, and gut barrier integrity across generations. The antibiotics exposure led to a decrease in gut microbial diversity over generations, along with aggravated anxiety behavior, microglia abnormalityies, and altered intestinal tight junction protein expression. Notably, the third generation of male mice exhibited impaired reproductive capacity. Oral sterile soil intervention restored gut microbial diversity in adult mice across generations, concomitantly rescuing abnormalities in behavior, microglia activity, and intestinal barrier integrity. In conclusion, this study simulated an important process of the progressive loss gut microbiota diversity in modern human and demonstrated the potential of sterile soil as a prebiotic to reverse this process. The study provides a theoretical and experimental basis for the research and therapeutic interventions targeting multiple modern chronic diseases related to intestinal microorganisms.

microbiology↗

Correcting PCR amplification errors in unique molecular identifiers to generate absolute numbers of sequencing molecules.

Unique Molecular Identifiers (UMIs) are random oligonucleotide sequences that remove PCR amplification biases. However, the impact that PCR associated sequencing errors have on the accuracy of generating absolute counts of RNA molecules is underappreciated. We show that PCR errors are the main source of inaccuracy in both bulk and single-cell sequencing data, and synthesizing UMIs using homotrimeric nucleotide blocks provides an error correcting solution, that allows absolute counting of sequenced molecules.

genomics↗

A hybrid single-cell demultiplexing strategy that increases both cell recovery rate and calling accuracy

Recent advances in single cell RNA sequencing allow users to pool multiple samples and demultiplex in downstream analysis, which greatly increase experimental efficiency and cost-effectiveness. Among all the demultiplexing methods, nucleotide barcode-based cell hashing has gained widespread popularity due to its compatibility and simplicity. Despite these advantages, certain issues of this technic remain to be solved, such as challenges in distinguishing true positive from background, high reagent cost for samples with large cell numbers, and unpredictable false negative and false doublet rates. Here, we propose a hybrid demultiplexing strategy that increases calling accuracy and cell recovery of cell hashing without adding experimental cost. In this approach, we computationally cluster all single cells based on their natural genetic variations and assign donor identity by finding the dominant hashtag in each genotype cluster. This hybrid strategy assigns donor identity to any cell that is identified as singlet by either genotype clustering or cell hashing, which allows us to demultiplex most majority of cells even if only a small fraction of cells are labeled with hashtags. When comparing its performance with cell hashing on multiple real-world datasets, this hybrid approach consistently generates reliable demultiplexing results with increased cell recovery and accuracy. Key PointsO_LIThe improved cut-off calling tool, HTOreader, accurately distinguishes true positive from background signal for each individual hashtag. C_LIO_LIThe hybrid demultiplexing strategy increases cell recovery of cell hashing by increasing cut-off calling accuracy and decreasing false negative and false double rates. C_LIO_LIThe hybrid strategy enhances cost-effectiveness of cell hashing and consistently produces reliable demultiplexing results, regardless of hashtag staining quality. C_LIO_LIThe hybrid strategy can be seamlessly integrated into a variety of single-cell experimental protocols and analytic pipelines. C_LI

bioinformatics↗

Accumulation of m6A exhibits stronger correlation with MAPT than beta-amyloid pathology in an APP NL-G-F /MAPT P301S mouse model of Alzheimer's disease

The study for the pathophysiology study of Alzheimers disease (AD) has been hampered by lack animal models that recapitulate the major AD pathologies, including extracellular {beta}-amyloid (A{beta}) deposition, intracellular aggregation of microtubule associated protein tau (MAPT), inflammation and neurodegeneration. We now report on a double transgenic APPNL-G-F MAPTP301S mouse that at 6 months of age exhibits robust A{beta} plaque accumulation, intense MAPT pathology, strong inflammation and extensive neurodegeneration. The presence of A{beta} pathology potentiated the other major pathologies, including MAPT pathology, inflammation and neurodegeneration. However, MAPT pathology neither changed levels of amyloid precursor protein nor potentiated A{beta} accumulation. The APPNL-G-F/MAPTP301S mouse model also showed strong accumulation of N6-methyladenosine (m6A), which was recently shown to be elevated in the AD brain. M6A primarily accumulated in neuronal soma, but also co-localized with a subset of astrocytes and microglia. The accumulation of m6A corresponded with increases in METTL3 and decreases in ALKBH5, which are enzymes that add or remove m6A from mRNA, respectively. Thus, the APPNL- G-F/MAPTP301S mouse recapitulates many features of AD pathology beginning at 6 months of aging.

neuroscience↗