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Wu, Y.

Publications and source records attributed to Wu, Y..

At least 163 records · Page 9Linked to original sources

Xylulose 5-Phosphate/Phosphate Translocator Mediates Carbon Allocation for Anabolic Metabolism in the Chlamydomonas Chloroplast

Metabolite movement into chloroplasts is essential for sustaining chloroplast anabolic metabolism and cellular growth, and yet how the specific factors/transporters that enable import and support metabolism under heterotrophic conditions (in the dark in the presence of fixed carbon) remain poorly understood. Here, we identify CreTPT10, a chloroplast envelope-localized transporter in the unicellular green alga Chlamydomonas reinhardtii (Chlamydomonas throughout) that, of the substrates tested, has the highest specificity for xylulose 5-phosphate (X5P). We also demonstrated that the loss of CreTPT10 caused a pronounced reduction in growth and respiratory activity in the dark, whereas no growth defects were observed in the tpt10 mutants when they were maintained in the light or under nutrient-limiting conditions. Furthermore, dark-grown tpt10 mutants exhibited markedly reduced levels of lipids, nucleotides, isoprenoids, and aromatic secondary metabolites, accompanied by coordinated repression of genes encoding enzymes associated with chloroplast-localized biosynthetic pathways. This metabolic suppression extended beyond the chloroplast, as genes associated with the mitochondrial respiratory chain and cell cycle progression were markedly downregulated in darkness. Together, these findings indicate that X5P import via CreTPT10 is critical for sustaining chloroplast anabolic metabolism and functionally coordinates chloroplast and mitochondrial energy metabolism to support heterotrophic growth.

plant biology↗

Tmn blocks phage spread via plasmolysis and triggers synergistic defence responses

Membrane-associated phage defences remain poorly understood. Here we characterise Tmn, a YobI-family transmembrane P-loop NTPase that protects bacteria from phage infection by establishing a plasmolysis-associated antiviral state. Upon recognising phage T2 RIIB protein, Tmn enhances ATP turnover and selectively exports Mg2+, causing rapid cytoplasmic collapse that arrests phage replication without detectable membrane depolarisation or gross leakage of the cell content. Cryo-electron microscopy shows that Tmn assembles into a decameric membrane complex with extended cytosolic arms, an uncommon architecture among P-loop NTPases. The cytosolic arms, including a solenoid-like repeat domain, mediate trigger interaction and determine specificity. In addition to its primary defence function, Tmn-driven ATP collapse activates otherwise silent ATP-depletion-sensing defences, including Gabija and Septu type I, providing a mechanistic basis for synergy among defence systems and limiting secondary phage spread. These findings demonstrate that Tmn is a membrane-integrated sensor-effector that couples phage recognition to metabolic collapse and coordinated multi-layered immunity.

microbiology↗

Longitudinal modality prediction learns gene regulatory patterns: insights from a single-cell competition

Simultaneous measurement of chromatin, transcriptomic, and proteomic features in single cells opens new avenues for modeling interactions between molecular layers during dynamic biological processes. Predicting one modality from another - such as inferring gene expression from chromatin profiles or protein abundance from RNA - has the potential to reveal regulatory relationships and enhance downstream analyses. However, conventional approaches for predicting gene regulation have largely failed and method development in modality prediction for regulatory inference has been limited. To explore effective modeling strategies and stimulate innovation, we generated a purpose-built longitudinal multimodal benchmarking dataset that captures early hematopoietic differentiation and organized the largest single-cell data competition to date, receiving over 27,000 submissions from 1,602 competitors worldwide. In our extensive analysis of the competition results, we demonstrated that top-performing approaches outperform state-of-the-art methods, and uncover how best-performing models captured biologically meaningful regulatory relationships between modalities. With ablation studies of the winning models, we identified feature-engineering strategies, model architectures and cross-validation schemes that are crucial for outstanding performance, and provide simplified, reproducible, light-weight code for state-of-the-art models. Together, the benchmark and analyses serve as an evaluation standard and guide future method development, including recently emerging foundation models, to advance our understanding of regulatory interactions in longitudinal, multimodal single-cell data.

bioinformatics↗

Transplanting ANXA1- CD8+ Naive T cells Delay Aging Through Senolysis

Immunosenescence is a hallmark of aging, yet strategies using defined immune subsets to counteract it are largely unexplored. We performed paired scRNA/TCR-seq on CD45 cells from human bone marrow (15 donors, 3-91 years). T cells were the most altered lineage, with CD8 naive T cell contraction and functional impairment. We identified an expanding ANXA1 CD8 naive subset with senescence signatures and impaired function. ANXA1-deficient CD8 T cells exhibited increased resting stemness and enhanced activation/cytotoxicity upon stimulation. ANXA1- cells showed senolytic activity in vitro and reduced senescence burden in vivo. Monthly transfer of syngeneic ANXA1- CD8 naive T cells into aged mice extended median lifespan by >30 weeks, improving cardiac function, bone density, motor coordination, and marrow immune microenvironment. Our study identifies ANXA1 as critical in CD8 naive T cell aging and establishes ANXA1- cell transfer as a strategy to counter immunosenescence and promote healthy aging.

immunology↗

Mutation-Resolved Drug Sensitivity Atlas Reveals Broad RAS(ON) Inhibitor Vulnerabilities and a STAT3 Co-Dependency in NRAS-Mutant Melanoma

NRAS-mutated melanoma remains a major unmet clinical need, with no approved targeted therapy and rapid progression on standard treatment. Tri-complex RAS(ON) inhibitors such as daraxonrasib (RMC-6236) and RMC-7977 have shown early clinical activity, but the mutation-specific sensitivity landscape and adaptive resistance programs in melanoma remain undefined. To address this, we generated an isogenic 3D melanoma platform and performed a saturation mutagenesis screen across 95 NRAS missense variants (>99% of clinically recurrent variants), profiling oncogenic fitness and responses to six RAS-targeting agents in spheroids and xenografts. RMC-6236 and RMC-7977 showed the broadest activity and stratified recurrent NRAS mutants into hypersensitive (G12 variants and Q61R/K/L; [~]95% of cases), moderately sensitive (G13D/R/V; [~]4%), and resistant (G60E and Q61P; [~]1%) classes. Structural analyses supported distinct mechanisms underlying reduced susceptibility in a restricted subset of variants. In sensitive genotypes, RAS(ON) inhibition elicited an adaptive cytokine- and RTK-associated survival program converging on STAT3. Co-inhibition of STAT3 enhanced apoptosis, suppressed MYC, and induced tumor regression in NRAS-mutant melanoma models. Together, these findings define a mutation-resolved therapeutic landscape for NRAS-mutant melanoma and identify adaptive STAT3 signaling as a rational target for combination therapy. Statement of Translational SignificanceNRAS-mutated melanoma lacks effective targeted treatments, and clinical responses to immunotherapy are suboptimal. This study presents the first comprehensive drug sensitivity map across 95 NRAS mutations in melanoma, identifying the pan-RAS(ON) inhibitors RMC-6236 and RMC-7977 as broadly effective agents. Multiple mutants with reduced susceptibility are identified, providing mutation-informed guidance for patient selection and clinical trial stratification. Mechanistic analyses reveal that RTK/cytokine-driven STAT3 activation functions as a key survival pathway under RAS(ON) blockade, and its inhibition markedly enhances the efficacy of pan-RAS(ON) inhibitors. These findings support mutation-guided use of RAS(ON) inhibition and highlight STAT3 co-targeting as a rational strategy to strengthen and prolong therapeutic responses in NRAS-mutated melanoma. Highlights- A functional and therapeutic atlas defines 95 recurrent and nonrecurrent NRAS missense variants in melanoma - RMC-6236 and RMC-7977 show broad but genotype-selective activity across major NRAS mutations - A restricted subset of recurrent NRAS mutants shows reduced susceptibility to RAS(ON) inhibition - RAS(ON) inhibition induces an adaptive STAT3 survival program that is therapeutically targetable

cancer biology↗

Experimental Time Points Guided Transcriptomic Velocity Inference

Time-series single-cell RNA sequencing enables longitudinal tracking of biological processes, yet cellular trajectory reconstruction informed by experimental time remains challenging. Existing trajectory inference methods either perform de novo reconstruction without leveraging experimental time points, or prioritize transitions between time points while paying less attention to intra-time-point dynamics. To reconcile experimental time points with local precision, we present CellDyc, a semi-supervised learning framework that leverages experimental time-point supervision to reconstruct transcriptomic velocities and recover an intrinsic gene-embedded time. CellDyc consistently outperforms existing approaches in reconstructing cellular trajectories across development, disease, and reprogramming contexts. Biologically, CellDyc provides novel insights, such as resolving temporal heterogeneity in erythroid maturation and quantitatively demonstrating that the immunosuppressive environment delays monocyte differentiation in glioblastoma. CellDyc integrates seamlessly with downstream tools like CellRank and remains robust even when only inferred temporal information is available. Collectively, CellDyc offers a rigorous, data-driven solution for deciphering time-resolved cellular dynamics.

bioinformatics↗

Targeted shedding of extracellular membrane proteins by induced protease recruitment

Extracellular targeted protein degradation has emerged as a promising therapeutic modality to eliminate proteins of interest (POIs) at the cell surface, by using bifunctional molecules to recruit natural recycling receptors or membrane-bound E3 ligases that redirect POIs to the lysosome. Another natural mechanism involves extracellular proteases that cleave and shed extracellular domains. Here, we exploit this endogenous mechanism by engineering bispecific antibody Shedders, that recruit a classic sheddase ADAM10 to POIs, inducing selective ectodomain shedding. We first targeted the immune checkpoint receptor LAG-3 and observed robust depletion of surface LAG-3 accompanied by accumulation of soluble LAG-3 fragments in both engineered cell lines and primary human T cells. Using biochemical and imaging assays, we confirmed that this antibody-induced shedding is restricted to extracellular protease activity and occurs independently of lysosomal trafficking. Notably, induced shedding of LAG-3 on activated primary T cells partially alleviated inhibitory signaling and reinvigorated IFN{gamma} secretion. We extended the scope of induced shedding by developing Shedders that recognize synthetic epitope-tags that enabling rapid assessment of substrate compatibility across diverse targets. Using this platform, we identified multiple immune modulatory cell-surface receptors, including IL6R, CD62L and MIC-A that can be targeted for shedding. In summary, this work establishes a new paradigm for targeted extracellular proteolysis and expands the toolkit for studying extracellular proteolysis with potential therapeutic benefit.

bioengineering↗

Unwinding of RNA G-quadruplexes induces mouse and human totipotency

Totipotent stem cells (TotiSCs) have significant application prospects in regenerative medicine and assisted reproductive technologies. The mRNAs of totipotency-related genes are rich in G-quadruplex (G4) structures, while the G4 density of pluripotency-related genes mRNAs is relatively low, suggesting a potential functional link between RNA G4s and the totipotent state. Nevertheless, how G4s are involved in the establishment or maintenance of mouse and human totipotency remains poorly understood. Here, we demonstrate that FC3, a small-molecule RNA G4 unwinder, enables efficient induction and maintenance of mouse and human TotiSCs (mG4TotiSCs and hG4TotiSCs). These FC3-induced TotiSCs closely recapitulate the molecular features of 2-cell-stage blastomeres via transcriptomic and epigenomic profiling. Functionally, both mG4TotiSCs and hG4TotiSCs exhibit totipotent capacity: they differentiate into embryonic and extraembryonic lineages in vitro and in chimeric embryos; moreover, they autonomously self-organize into blastocyst-like structures without exogenous signalling. Mechanistically, we identify that Gata2 mRNA, a G4-containing transcript, is essential for FC3-mediated reprogramming. Genetic disruption of Gata2 would abolish totipotency induction. Collectively, RNA G4 unwinding is a new regulatory axis governing totipotency acquisition and maintenance, providing insight into the functional interplay between nucleic acid secondary structures and cell fate plasticity.

cell biology↗

A Multimodal Single-Cell Epigenomic and 3D Genome Atlas of the Human Basal Ganglia

The basal ganglia (BG) underlie motor control, reward processing, and many neurological and psychiatric disorders, but a comprehensive epigenomic and 3D-genome atlas of the human BG is lacking. Here we present a multimodal single-cell atlas profiling DNA methylation and 3D chromatin conformation in 261,331 nuclei (snm3C-seq) across eight subregions, resolving 12 classes, 31 subclasses, and 59 groups. Harmonized under the HMBA basal-ganglia consensus taxonomy, this atlas integrates with matched RNA, ATAC-seq, and histone-modification data across five regulatory layers. We identify millions of cell-type- and region-specific differentially methylated regions enriched for distinct transcription factor motifs and link them to disease-associated heritability. Neuron-specific loops dominate cell-type-specific 3D contact remodeling, while most non-neuron-specific loops are constitutive. Among spiny projection neurons (SPNs), chromatin loops, rather than TAD boundaries, distinguish D1, D2, and eccentric SPN subclasses, with eccentric SPNs showing the most loop-level reorganization among the three. We characterize STR D2 SMYD2-HTR7 SPN, a newly recognized POU6F2 D2-SPN subtype, and reveal region-specific methylation and contact gradients of disease-associated genes, including CADM1 and PDE8B. Integrative gene-regulatory networks reconstruct cell-type-resolved enhancer-promoter links to interpret Parkinsons disease risk variants at SNCA. Finally, MERFISH spatial profiling combined with cross-species Patch-seq identifies non-SPN neuronal subtypes, including a MOXD1 striosomal STR FS PTHLH-PVALB GABA subtype with distinct electrophysiology, partitioning across the striatal matrix-striosome boundary. HighlightsO_LIA multimodal single-cell atlas maps DNA methylation and 3D genome architecture across human basal ganglia cell types and subregions. C_LIO_LINeuron-specific loops dominate cell-type-specific 3D contact remodeling in the human BG, whereas most non-neuron-specific loops are constitutive. C_LIO_LISpiny Projection Neuron (SPN) subtypes exhibit regionally organized epigenomic and 3D genome signatures that align with dorsal-ventral identities. C_LIO_LIChromatin loops are the primary distinguishing feature among D1, D2, and eccentric SPN subclasses, with eccentric SPNs being the most 3D-reorganized. C_LIO_LIIntegrated regulatory maps link cell-type-specific enhancers to disease-associated genetic risk in the human basal ganglia. C_LIO_LINon-SPN interneurons differ in distribution and in transcriptional and epigenetic identity across the matrix-striosome boundary. C_LI

neuroscience↗

Resident cardiac macrophages are not required for normal atrioventricular node conduction

Resident cardiac macrophages are understood to facilitate atrioventricular (AV) node conduction because they purportedly couple to AV node myocytes via connexin43 (Cx43) containing gap junctions. We tested this mechanism using biophysical modelling, high-resolution imaging of mouse and human AV conduction tissue, and pharmacological macrophage depletion. In silico, coupling macrophage membrane phenotypes to HCN4+ AV node myocytes imposed an electrotonic load that suppressed pacemaking and promoted conduction slowing, including stable 2:1 block in strand simulations. Anatomically, HCN4-defined components of the mouse AV conduction axis were essentially devoid of Cx43 and overlap of CD68+ macrophages and Cx43 was negligible in both mouse AV node and human penetrating bundle. Finally, near-complete macrophage depletion with CSF1R inhibition (PLX5622) did not alter AV electrical activity in vivo or ex vivo. Together, these data argue against a physiologically relevant role for Cx43-mediated macrophage-myocyte electrical coupling in normal AV node function. HIGHLIGHTSO_LIModelling predicts that AV node automaticity and conduction would be suppressed if macrophages coupled to AV node myocytes C_LIO_LIThe mouse AV conduction axis is essentially devoid of Cx43, currently considered responsible for macrophage-AV node myocyte coupling C_LIO_LIOverlap of macrophages and Cx43 expression is not discernible in the Cx43-expressing human distal AV node C_LIO_LIMacrophage depletion by CSF1R inhibition does not impact AV electrical activity in vivo or ex vivo C_LI

physiology↗

Predicting Sex-Specific Antiarrhythmic Strategies for Atrial Fibrillation through a Regression-Guided Computational Modeling Pipeline

Atrial fibrillation (AF), the most common sustained cardiac arrhythmia, is a major contributor to stroke, heart failure, and mortality worldwide. Although AF affects both men and women at a similar rate, accumulating experimental and clinical evidence indicates that its underlying mechanisms, disease progression, and treatment responses differ by sex. However, current antiarrhythmic drug development and clinical management of AF remains largely sex neutral, likely contributing to limited efficacy and increased adverse effects. To address this gap, we developed a computational drug-screening pipeline based on experimentally constrained, sex-specific human atrial cardiomyocyte models to predict and evaluate sex-specific pharmacological strategies for AF. The pipeline integrates multivariable regression with mechanistic modeling to systematically test multi-target combinations of ion channel inhibitors and Ca2+ handling modulators and identify interventions that reduce arrhythmia vulnerability by restoring sex-specific electrophysiological and Ca2+ handling properties toward normal sinus rhythm (nSR). Application of this approach revealed a greater number of successful inhibitory drug combinations in males than in females. In males, optimal recovery to nSR primarily required inhibition of Na+ and K+ channels to prolong repolarization and refractoriness, increase Ca2+ transient amplitude (CaTAmp), and reduce susceptibility to action potential duration (APD) alternans. In females, modulation of Ca2+-related pathways was additionally required to suppress delayed afterdepolarizations (DADs). Forward single-cell simulations confirmed the predictions of the drug-analysis pipeline, demonstrating recovery of APD, CaTAmp, and arrhythmia vulnerability indices without introducing instabilities. Importantly, extension of these interventions to two-dimensional atrial tissue simulations demonstrated that sex-specific drug strategies reduce vulnerability to triggered activity, while suppression of reentry was most effective when combined with partial recovery of cell-cell coupling. Our results establish a multiscale computational pipeline for identifying sex-informed, multi-target antiarrhythmic therapies, amenable to experimental validation and translation to the clinic. Clinical PerspectiveO_ST_ABSWhat is KnownC_ST_ABSO_LIAtrial fibrillation arises from multiple interacting multiscale mechanisms, which limit the effectiveness of single-target therapies. C_LIO_LICurrent single-target antiarrhythmic drugs for atrial fibrillation show more limited efficacy and higher adverse event rates in women than in men C_LI What the Study AddsO_LIThis study demonstrates that effective pharmacologic strategies require different combinations of ion channel and calcium handling modulation in males versus females with persistent (chronic) atrial fibrillation. C_LIO_LIIn males, coordinated Na+ and K+ channel inhibition most effectively improves electrical stability, whereas in females additional targeting of Ca2+ handling is required to suppress triggered activity. C_LIO_LISex-specific multi-target drug strategies including partial recovery of intercellular coupling suppress triggered activity and reentry in atrial tissue while preserving conduction. C_LI

pharmacology and toxicology↗

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↗

Identification of collaborative cross mouse strains susceptible to chlamydial induction of hydrosalpinx

Sexually transmitted infection with Chlamydia trachomatis can cause pathology, such as hydrosalpinx, in the upper genital tract, leading to infertility. To investigate how genetic variation affects chlamydial pathogenicity, we screened five strains of Collaborative Cross (CC) mice for susceptibility to intravaginal infection and hydrosalpinx induction by C. muridarum, a mouse-adapted chlamydial species used extensively to reveal chlamydial pathogenic mechanisms. In terms of susceptibility to genital chlamydial infection, the five CC strains fell into two categories: CC011 and CC012 were resistant, while CC037, CC042 & CC080 were susceptible. The resistant strains shed significant levels of live organisms from the genital tract for only [~]2 weeks, whereas the susceptible strains shed for [~]4 weeks. However, the resistant CC012 mice developed the highest level of hydrosalpinx, while the susceptible CC042 mice were fully resistant to hydrosalpinx induction. None of the CC mice developed spontaneous hydrosalpinx in the absence of chlamydial infection. The above results, validated macroscopically and microscopically, indicate no correlation between pathology and genital infection, as observed in other inbred mice. Nevertheless, among the two infection-resistant strains, CC012 developed more severe hydrosalpinx than CC011, and hydrosalpinx was positively correlated with live organism shedding from rectal swabs but not from vaginal swabs, supporting a potential role of gastrointestinal chlamydia in chlamydial genital pathogenicity. The above results lay a foundation for using CC mice to further map the genetic determinants that regulate host susceptibility to chlamydial infection and pathogenicity in the female genital tract.

microbiology↗

IR-B deficiency and fatty acid dysregulation accelerate prostate cancer progression via PI3K/AKT signaling

The insulin receptor (IR) is markedly overexpressed in both human and mouse prostate cancer, with a significant elevation in the IR-A/IR-B ratio across patient tissues, cell lines, and Hi-Myc mouse prostates. To elucidate the role of IR-B in prostate tumorigenesis, we generated a prostate-specific IR-B knockout (KO) mouse model using Pbsn-Cre-driven recombination. Prostate-restricted loss of IR-B was confirmed at the transcript level and did not affect other tissues. Crossing these mice with Hi-Myc transgenics revealed that IR-B deficiency promotes accelerated progression to invasive adenocarcinoma, characterized by enhanced cellular proliferation and atypical histopathology. Transcriptomic and metabolomic profiling of dorsolateral prostate lobes demonstrated activation of PI3K/AKT and mTOR signaling, along with upregulation of IRS1/2/4 and IGF2. Metabolite analyses indicated elevated fatty acid levels and enhanced lipolysis pathways, implicating metabolic reprogramming in tumor progression. Notably, glucose and lipid metabolism genes, including GLUT1, GLUT12, FASN, and GPR120, were upregulated, accompanied by an increased BCL2/BAX ratio, suggesting apoptosis inhibition. Functional studies further revealed opposing roles of dietary fatty acids: {omega}-3 polyunsaturated fatty acids (EPA, DHA) suppressed prostate cancer cell survival, proliferation, and PI3K/AKT signaling while promoting apoptosis, whereas {omega}-6 fatty acid (arachidonic acid) exerted pro-tumorigenic, anti-apoptotic effects. Collectively, these findings identify IR-B loss as a driver of metabolic and signaling reprogramming that accelerates prostate tumorigenesis, while highlighting {omega}-3 fatty acids as potential modulators counteracting IR-B-deficient prostate cancer progression.

cancer biology↗

Compression Detects Changes in Spiking Neural Data from Cortical Lesions

1ObjectiveThe complexity of neural data changes as the brain processes information during events. Universal lossless compression algorithms, which are broadly applicable and grounded in information theory, identify and exploit redundancies in data in order to compress it to essentially-optimal sizes regardless of underlying statistics. These algorithms may be used to conveniently and efficiently estimate a given signals Shannon entropy rate, a biologically relevant measure of the complexity of a signal. It is therefore natural to explore their effectiveness in the analysis of spiking neural data. ApproachThis work focuses on using compression to analyze recordings (96-channel Utah arrays) taken from motor cortex of animals performing reaching tasks for three days before and three days after administering electrolytic lesions (Subject U: 4 lesions, H: 3). In particular, we use the inverse compression ratio (ICR), which compares the sizes of compressed and uncompressed data to estimate the amount of statistically unique information. We calculate ICR with temporally-independent lossless compression (gzip) and temporally-dependent lossy compression (H.264, MPEG-2). Compression-based ICR was compared to single-neuron measures used to understand spiking data, such as average firing rates and Fano factor. Compression is also compared to common dimensionality reduction techniques, principal component analysis (PCA) and factor analysis (FA). Main ResultsStatistical tests on aggregate data comparing each metric before and after lesioning reveal that ICR is able to significantly (Mann-Whitney U test, p < 0.01) detect lesions with higher accuracy than single-neuron metrics, but not dimensionality reduction (ICR methods: 85.7%, single-neuron methods: 78.6%, dimensionality reduction: 100%). Additionally, statistical results on the same data show that ICR metrics remain more stable than single-neuron methods after lesion. The bitrate parameter of lossy compression algorithms is swept to better understand the effect of information rates and "optimal" compression on lesion detection performance. Our conclusions are confirmed by the same analyses performed on several different simulated neural datasets. SignificanceThese results suggest that compression algorithms may be a useful tool to detect and better understand perturbations to the underlying structure of neural data. Information-theoretic analyses may complement techniques like dimensionality reduction and firing rate tuning as a convenient and useful tool to characterize neural data.

neuroscience↗

TRPC6 channel inhibition disturbs store-operated Ca2+ entry to delay proliferation in bladder cancer

Background and ObjectiveDespite its prevalence, bladder cancer (BC) remains an unsolved pathogenesis. It is believed that TRPC6 channels have unique electrophysiological properties that contribute to intracellular Ca2+ signalling and tumorigenesis in cells. However, the mechanism by which TRPC6 contributes to BC progression and intracellular Ca2+ homeostasis remains unclear. MethodIn this study, TRPC6 expressions in paired BC and adjacent normal tissues were measured by immunohistochemistry. A KEGG pathway enrichment analysis was conducted to determine TRPC6s potential contribution to BC. Ca2+ imaging analysis was performed to explore the contribution of TRPC6 in the BC cell. Flow cytometry and Cell Counting Kit-8 assay were performed to explore the effects of TRPC6 on the proliferation of BC. The impacts of TRPC6 SOCE on PI3K/Akt/mTOR pathway were measured by western blot. Based on the above bunch of studies, TRPC6 was found to be overexpressed in human BC tissue, which correlated with poor survival rates for patient overall survival (OS). We used the TRPC6-specific antagonist SAR7334 to explore and reveal significant inhibition of BC cell proliferation. Mechanistically, TRPC6 mediated cytosolic Ca2+ and regulation of SOCE, leading to the activation of the IP3K/AKT/mTOR pathway. ResultsWe found that SAR7334 arrested the phosphorylation of PI3K and Akt, thus causing a significant decrease in phosphorylated mTOR. Similar effects were observed for the SOCE-specific antagonist MRS1845. In contrast, the Akt inhibitor MK2206 did not alter the SOCE in BC cells. Conclusionsour results indicate that the pharmacological inhibition of TRPC6 arrests tumour cell proliferation through SOCE targeting the PI3K/Akt/mTOR pathway. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=101 SRC="FIGDIR/small/702689v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@bf783aorg.highwire.dtl.DTLVardef@6e3487org.highwire.dtl.DTLVardef@13aad23org.highwire.dtl.DTLVardef@13cfe7e_HPS_FORMAT_FIGEXP M_FIG C_FIG Schematic of proposed pathway. A model for summarizing TRPC6 contributes to cell proliferation in bladder cancer. TRPC6 specific inhibitor SAR7334 alter cellular cytosolic Ca2+ and SOCE, thus arrested phosphorylation of the PI3K/Akt pathway and the proliferation of bladder cancer cells.

cancer biology↗

ATG-18 drives longevity in an HLH-30-dependent manner

Enhancing autophagy increases lifespan and healthspan in animal models, yet the precise molecular mechanisms underlying these effects are not fully understood. Here we show that overexpression of the essential autophagic gene atg-18 extends the lifespan of C. elegans. We describe a previously unknown, pleiotropic mechanism by which atg-18 impacts lysosomes and extends lifespan through the transcription factor hlh-30, the master regulator of lysosomal biogenesis. We show that, under stress conditions, HLH-30 requires atg-18 for nuclear translocation. Furthermore, atg-18 overexpression broadly improves health and stress resilience yet paradoxically increases early-life susceptibility to lethal heat stress. In contrast, enhances heat-stress survival a loss-of-function of function mutation in atg-18 enhances heat-stress survival, uncovering a temporal-specific effect of atg-18. These finding suggest an ATG-18--HLH-30 autophagy--lysosome pathway that plays a key role in lifespan and healthspan. Bulleted main discoveriesO_LIATG-18 overexpression increases C. elegans lifespan and plays an important role in resilience against starvation and heat stress. C_LIO_LIATG-18 is required for nuclear translocation of HLH-30 C_LIO_LIHLH-30 is required for ATG-18--mediated lifespan extension C_LIO_LIATG-18 positively regulates lysosomal biogenesis, suggesting a novel role as a molecular coordinator between autophagy and the lysosomal network. C_LI

molecular biology↗

Wetness modulates the effects of grazing on net ecosystem productivity in global grasslands

Overgrazing has induced widespread grassland degradation globally. However, how grazing intensity affects ecosystem carbon dioxide (CO2) fluxes with wetness fluctuations in grasslands at a global scale remains poorly understood. Here we measured ecosystem CO2 fluxes covering the 7th to 11th years of a continuous grazing experiment in a typical steppe, and conducted a meta-analysis of 585 observations by collecting relevant data in global grasslands. Our experimental results showed that mean gross primary productivity (GPP) and ecosystem respiration (ER) were decreased under heavy grazing (HG) compared with control without grazing (CK), whereas net ecosystem productivity (NEP) was not different between HG and CK in the typical steppe. The NEP was higher under light grazing in the wetter years, but it was not different between LG and CK under drier years in the typical steppe. The structural equation model showed that grazing altered NEP by increasing soil temperature and relative growth rate, while decreasing AGB. In contrast, grazing decreased GPP, ER and NEP, respectively, in global grasslands. Both our field experiment and the meta-analysis revealed that the response of NEP to light grazing, rather than heavy grazing, was lineally correlated with the wetness index. Higher wetness and aboveground biomass (AGB) increased the response of NEP to grazing in global grasslands. However, heavy grazing reduced NEP and AGB even under higher wetness indices in global grasslands, resulting from a loss of their resilience in long-term heavy grazing. These findings indicate that light grazing appears to be a promising management to promote plant relative growth rate and carbon sequestration. Overall, the meta-analysis and field experiment jointly provide global perspectives on the response of ecosystem CO2 fluxes to grazing intensity and improve our understanding of the factors influencing the response of ecosystem CO2 fluxes to grazing intensity.

ecology↗