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Deng, B.

Publications and source records attributed to Deng, B..

At least 19 recordsLinked to original sources

Sex-dimorphic immune trajectories across the canine lifespan and early-life signatures of geroprotective interventions

Canine models are invaluable for translational geroscience, but widespread gonadectomy in companion dogs obscures natural sex-specific aging trajectories. Here, we characterize the age-associated hematologic and serum cytokine profiles of 80 intact laboratory Beagles spanning 1 to 11 years. Contrary to classical linear models of immunosenescence and inflammaging, we reveal that canine immune aging is highly dynamic and sexually dimorphic. While absolute leukocyte counts declined continuously, cytokine remodeling was sex-specific: intact males exhibited extensive age-dependent inflammatory restructuring, whereas females demonstrated restricted fluctuations. To establish baseline geroprotective signatures, we evaluated 24 young beagles following a 90-day intervention with rapamycin, canagliflozin, or dietary restriction. Rapamycin induced robust immune modulation, while canagliflozin prompted early, sex-biased weight loss and narrower cytokine responses. Together, our findings demonstrate that canine immune aging involves complex, sexually dimorphic remodeling. By utilizing an intact cohort to isolate natural dimorphic trajectories, we provide a crucial foundation for developing precision, sex-optimized geroprotectors.

physiology↗

Species-Specific Roles of RIPK1 and TRADD in TNF-Induced Cell Death Reveal a Translational Gap Between Mouse Models and Human Biology

Mouse models have historically been central to studies of TNF-induced cell death and guided pharmaceutical translation into clinic, based on the assumption that TNF signaling is conserved between human and mouse. Here, our work uncovers critical species-specific differences between the two. By systematically dissecting the roles of RIPK1, TRADD, and sensitivity to RIPK1 inhibitors in TNF signaling--including RIPK1 kinase-dependent and-independent apoptosis--we found that both apoptosis modalities diverge between human and mouse cells. In mouse cells, RIPK1 suppresses TRADD-mediated kinase-independent apoptosis, whereas in human cells, RIPK1 and TRADD act redundantly. Moreover, RIPK1 inhibitors block kinase-dependent apoptosis in mouse but not human cells, despite effectively inhibiting RIPK1 S166 phosphorylation. Cross-species complementation revealed that these discrepancies stem not from RIPK1 itself but from cell-context differences. These findings echo the clinical failures of RIPK1 inhibitors despite efficacy in mouse models and underscore the need for humanized models and therapeutics that more faithfully predict clinical outcomes.

Cell Biology↗

mTORC1 Directs TNF-Induced Life-or-Death Decisions via Complex I Destabilization

The transition from tumor necrosis factor (TNF)-induced plasma membrane-bound complex I to cytosolic death-inducing complex II switches cells from survival to death. However, the precise regulation of this fatal decision is incompletely understood. Here, we show that mTORC1 promotes this transition by destabilizing later-stage complex I without affecting its initial assembly. Inhibition of mTORC1 unleashes ATG9A and FIP200 activity, thereby promoting the accumulation of CHUK (IKK) in complex I. CHUK scaffolds the kinase-active IKK{beta} to stabilize complex I and prevent complex II formation. Activation of this ATG9A/FIP200-CHUK/IKK{beta} axis protects against TNF-induced fulminant hepatitis while compromises antibacterial defense against Staphylococcus aureus. This mTORC1-governed life-or-death transition provides therapeutic insight into TNF-related pathologies--including cancer, metabolic tissue injury, and microbial infections--where mTORC1 activity is frequently suppressed.

Cell Biology↗

Single-cell transcriptomics reveals transcriptional diversity of sea cucumber perivisceral fluid coelomocytes

Echinoderms possess a complex immune system, primarily relying on coelomocytes - immune cells circulating in coelomic fluids. Over the last few decades, various coelomocytes have been described based on morphological features, with holothuroids exhibiting the highest diversity of cell morphotypes among the different echinoderm classes. However, while the overall immune function of these cells is broadly accepted, their respective functions remain unclear, and molecular data specific to the different cell types are still limited in the literature. In this study, we address this gap in functional information and molecular data by using single-cell RNA sequencing (scRNA-seq) on coelomocytes from the perivisceral fluid of Holothuria forskali. We identified 10 distinct clusters, each assumed to correspond to a distinct transcriptional coelomocyte population. Among these, cluster 0 occupies a central position relative to the others, suggesting it may represent "progenitor cells", whereas cluster 6 is markedly divergent from all other clusters. Functional enrichment analyses revealed that some clusters ensure key immune functions, including pathogen recognition, phagocytosis, complement activation and redox balance regulation. In addition, examination of the processed samples under a microscope confirms the presence of a small proportion of recently discovered carotenocytes (7.0%) in the perivisceral fluid, a cell type rich in carotenoids. By using transcriptomics data previously obtained for this cell type by bulk RNA sequencing (bRNA-seq), it was possible to confidently identify cluster 6 as carotenocytes and provide further insights into their gene expression. While further analyses are needed to link other clusters to the different morphotypes previously described in the literature, this pioneer study presents preliminary data on the functional diversity of holothuroid coelomocytes, which could be of broad interest for a better understanding of holothuroid immunity as well as for the study of immune cell lineage evolution across deuterostomes.

evolutionary biology↗

Deep learning-guided design of cell type-specific AAV promoters

Precise cell type targeting is critical for both clinical and experimental applications of adeno-associated viral (AAV) vectors, yet engineering vectors with cell type-specific activity remains a challenge. Here, we compared three strategies leveraging single-cell chromatin accessibility data to design cell type-specific AAV promoters, including a deep learning-based method to generate de novo regulatory sequences. When applied to target retinal ganglion cells or horizontal cells in mouse retina, deep learning-guided design consistently outperformed rational approaches, yielding synthetic promoters with stronger and more specific expression in vivo. Synthetic AAV promoters supported diverse transgenes, enabling the recording and ablation of targeted cells. Promoter activity was also maintained in human retinal organoids, suggesting that deep learning-designed sequences may be suitable for translation. Our findings highlight the potential of deep learning to synthesize cell type-specific AAV promoters and establish a versatile platform for cell type targeting with broad implications for gene therapy and basic research.

synthetic biology↗

Proteolytic processing of Argonautes in multiphase condensates promotes transgenerational epigenetic inheritance

Epigenetic information can be memorized in perinuclear condenates to transmit across generations to modulate gene expression in descenent. Here, we identify a conserved N terminal proteolytic mechanism in Caenorhabditis elegans that is essential for small RNA-mediated transgenerational epigenetic inheritance (TEI) and for maintaining germline immortality. Two conserved, perinuclear germ granule subcompartments-enriched N-terminal processing peptidases, APP-1 and DPF-3, act cooperatively to trim N-terminal intrinsically disordered regions of the Argonaute proteins WAGO-1, WAGO-3, and WAGO-4. This processing shields these Argonautes from proteasome-mediated protein degradation, prevents the loss of their associated small RNAs, and promotes their accumulation in germ granules subcompartments. In contrast, unprocessed WAGOs are recognized and destabilized by the conserved E3 ubiquitin ligases RNF-1 and UBR-7. We propose that this cooperative proteolytic mechanism adds another layer of sspatiotemporal regulation over small RNA-directed epigenetic inheritance and may represents a broadly conserved strategy for regulating protein homeostasis and gene expression programs.

cell biology↗

Sex-dependent cortico-amygdala circuits controlling emotion recognition

In social species, the ability to recognize others emotional states is essential for appropriate social interactions, yet it often declines with age and is impaired in various neurodevelopmental and neurodegenerative disorders. While emotion recognition has been characterized in both humans and rodents, the underlying neural circuits and how they vary by sex and age remain poorly understood. Here, we used a negative Emotional state Discrimination Task (EDT) in TRAP2 transgenic mice to map brain regions engaged during negative emotion recognition in young and aged animals. Young male and female mice successfully discriminated emotionally altered conspecifics, recruiting the basolateral amygdala (BLA) and medial orbitofrontal cortex (MO) in a sex-specific manner. Fiber photometry revealed distinct activation dynamics in these regions, and chemogenetic inhibition of bidirectional BLA-MO projections abolished emotion recognition in male but not female mice. Notably, young human participants also showed sex-specific recruitment of BLA and OFC during negative facial emotion recognition. Moreover, aging selectively impaired emotion recognition in male mice, coinciding with reduced BLA activity. Remarkably, chemogenetic activation of BLA in aged male mice rescued this deficit. Together, these findings identify a sex-dependent BLA-MO circuit as a conserved neural substrate for emotion recognition and demonstrate that age-related impairments can be reversed through targeted circuit-level intervention.

neuroscience↗

The Adipomyokine Follistatin-like-1 Restores Cardiovascular Function in a Swine Model of Diabetic Myocardial Infarction

Obesity, diabetes, and metabolic syndrome increase the incidence and complicate the management of myocardial infarction (MI). Current treatments do not adequately blunt the progression to chronic ischemic heart disease and heart failure, making these diseases the largest cause of mortality worldwide. Insulin resistance and metabolic syndrome were induced in obese Ossabaw swine prior to ischemia/reperfusion injury-induced MI. Subcutaneous administration of the adipomyokine Follistatin-like-1 (recombinant non-glycosylated human FSTL1, ngFSTL1) for two weeks, beginning one month following myocardial infarction, decreased infarct necrosis, increased blood flow, and increased cardiomyocyte proliferation within the infarct region, leading to improved systolic and diastolic function. ngFSTL-1 also enhanced coronary and peripheral vascular function by increasing BKCa channel-dependent vasodilatory capacity. We conclude that subcutaneous ngFSTL1 ameliorated clinically relevant parameters of cardiac and vascular dysfunction in a preclinical swine model of diabetic MI, and suggest FSTL1 treatment may be broadly efficacious in humans. ARTICLE HIGHLIGHTSO_LISubcutaneous administration of recombinant human non-glycosylated FSTL1 (ngFSTL1) for 2 weeks, 1 month after infarction/reperfusion injury, improved cardiac function in a preclinical obese swine model of diabetic MI. C_LIO_LIngFSTL1 treatment induced cardiomyocyte proliferation and improved coronary perfusion, resulting in reduced necrosis of the infarct region. C_LIO_LIngFSTL1 treatment increased blood flow through peripheral arterioles, including cerebral and skeletal muscle, in addition to cardiac arterioles. C_LIO_LISystemic delivery of the non-glycosylated form of the adipomyokine FSTL1 might be an effective treatment for diabetic MI. C_LI

physiology↗

Sequence engineering at non-motif modulator residues yields a peptide that effectively targets a single PDZ protein in a disease-relevant cellular context

Highlights- PDZ domains are critical components of many cellular, disease-relevant systems - Overlapping specificity complicates selective targeting of PDZ interaction networks - We engineered a single-PDZ peptide inhibitor using non-motif preferences - Mass-spectrometry based experiments confirm single-PDZ binding - Our inhibitor increases chloride efflux in a cystic fibrosis cellular model PDZ interaction networks are finely-tuned products of evolution. These widespread binding domains recognize short linear motifs (SLiMs), usually at the C-terminus of their interacting partners, and are involved in trafficking and signaling pathways, the formation of tight junctions, and scaffolding of the post-synaptic density of neurons, amongst other roles. Typically, a single PDZ domain binds multiple targets; conversely, each PDZ-binding protein engages several PDZ domains, dependent on cellular conditions. Historical PDZ binding motifs rely on two key positions for binding. However, previous insights on modulator, or non-motif, selectivity preferences reveal that these limited motifs are insufficient to describe PDZ-mediated interactomes, consistent with the observation that the degree of promiscuity is much more limited than predicted by defined binding classes. Here, we use these principles to engineer and test a peptide-based inhibitor capable of interacting with a single PDZ domain-containing protein in a disease-relevant cellular system. We first interrogate a previously developed sequence selective for cystic fibrosis transmembrane conductance regulator (CFTR)-Associated Ligand (CAL), one of five PDZ domains known to bind the CFTR C-terminus, probing for off-target PDZ partners. Once identified, we use parallel biochemical and structural refinement to eliminate these interactions and introduce a CAL PDZ inhibitor with unprecedented PDZ domain selectivity. We test and verify specificity using relevant cellular PDZ target networks in a mass spectrometry-based approach. Our resultant selective inhibitor enhances chloride efflux when applied to polarized patient bronchial epithelial cells, as well as confirms that engineering an effectively single-PDZ peptide is possible when modulator preferences are applied.

biochemistry↗

Computational Assessment of Circularization Impact on Saxitoxin G-quadruplex Aptamer Performance

Although high-affinity and high-specificity aptamers can be obtained by SELEX (Systematic Evolution of Ligands by Exponential Enrichment), and have good activity in vitro, their performance in vivo is poor. This is mainly because of the degradation of linear nucleic acids by nucleases in body fluids and the difficulty of maintaining stable 3D structures in complex body fluid environments, which seriously hinders the clinical application of aptamers. This makes circular aptamers, which can resist degradation and are more stable in complex body fluid environments, an attractive option. However, the cyclization process may have a considerable impact on the structure of the original linear aptamer, and blind cyclization may lead to a decrease in its affinity. Here, we developed a new method to guide the cyclization of saxitoxin (STX) aptamers based on molecular computation, and verified the activity of circular aptamers through bioactivity experiments to further verify the authenticity and reliability of our methods. Consistent with the computational analysis, although circularization disrupts the G4 structure, circular aptamer not only has a higher affinity than the linear one but also provides certain protection to mice and greatly prolongs their survival, which proves the accuracy and reliability of the circular structure designed by our computational method. Our findings provide important ideas for better guidance in the design of circular aptamers and demonstrate their great potential in therapeutic applications.

biochemistry↗

High-pressure Golgi neuronal staining for X-ray whole-brain imaging

Whole-brain imaging has revolutionized neuroscience research, providing comprehensive insights into neural networks across the entire brain. This powerful approach has greatly advanced our understanding of brain functions and the mechanisms underlying various diseases. One primary challenge in whole-brain imaging technology is to achieve high-resolution observation of neural networks at large scales. Although Golgi method allows labeling random neurons in their entirety in the brain, visualizing individual dendritic trees, and tracing long-distance axonal projections, the lengthy processing time pose a limit on its use, i.e., staining a mouse whole-brain sample of just 300 mm3 takes over two weeks. Here, we developed a rapid staining technique for whole-brain neurons using high-pressure assisted Golgi (HP Golgi). This method significantly reduced the staining time for mouse whole-brain neurons from 16 days to only 4 days. We demonstrated the broad applicability of the HP Golgi method across various model organisms, achieving whole-brain neuronal staining in zebrafish, mice, and rats. Further, we successfully performed rapid staining of hippocampal neurons in an intact pig brain, which is difficult to achieve with the classic Golgi-Cox method. We also demonstrated that the combination of the HP Golgi method with synchrotron-based X-ray microscopy for high-resolution imaging of whole-brain neurons in mice. This HP Golgi method enables fast and high-resolution neuronal imaging in large model organisms, showcasing its broad applicability for diverse applications.

biophysics↗

Morphological map of under- and over-expression of genes in human cells

Cell Painting images offer valuable insights into a cells state and enable many biological applications, but publicly available arrayed datasets only include hundreds of genes perturbed. The JUMP (Joint Undertaking in Morphological Profiling) Cell Painting Consortium perturbed roughly 75% of the protein-coding genome in human U-2 OS cells, generating a rich resource of single-cell images and extracted features. These profiles capture the phenotypic impacts of perturbing 15,243 human genes, including overexpressing 12,609 genes (using open reading frames, ORFs) and knocking out 7,975 genes (using CRISPR-Cas9). We mitigated technical artifacts by rigorously evaluating data processing options and validated the datasets robustness and biological relevance. Analysis of phenotypic profiles revealed novel gene clusters and functional relationships, including those associated with mitochondrial function, cancer, and neural processes. The JUMP Cell Painting genetic dataset is a valuable resource for exploring gene relationships and uncovering novel functions.

bioinformatics↗

BioInformatics Agent (BIA): Unleashing the Power of Large Language Models to Reshape Bioinformatics Workflow

Bioinformatics plays a crucial role in understanding biological phenomena, yet the exponential growth of biological data and rapid technological advancements have heightened the barriers to in-depth exploration of this domain. Thereby, we propose Bio-Informatics Agent (BIA), an intelligent agent leveraging Large Language Models (LLMs) technology, to facilitate autonomous bioinformatic analysis through natural language. The primary functionalities of BIA encompass extraction and processing of raw data and metadata, querying both locally deployed and public databases for information. It further undertakes the formulation of workflow designs, generates executable code, and delivers comprehensive reports. Focused on the single-cell RNA sequencing (scRNA-seq) data, this paper demonstrates BIAs remarkable proficiency in information processing and analysis, as well as executing sophisticated tasks and interactions. Additionally, we analyzed failed executions from the agent and demonstrate prospective enhancement strategies including selfrefinement and domain adaptation. The future outlook includes expanding BIAs practical implementations across multi-omics data, to alleviating the workload burden for the bioinformatics community and empowering more profound investigations into the mysteries of life sciences. BIA is available at: https://github.com/biagent-dev/biagent.

bioinformatics↗

Intermittent energy restriction inhibits tumor growth and enhances paclitaxel response in a transgenic mouse model of endometrial cancer

ObjectiveOverweight/obesity is the strongest risk factor for endometrial cancer (EC), and weight management can reduce that risk and improve survival. We aimed to establish the differential abilities of intermittent energy restriction (IER) and low-fat diet (LFD), alone and in combination with paclitaxel, to reverse the procancer effects of high-fat diet (HFD)-induced obesity in a mouse model of EC. MethodsLkb1fl/flp53fl/fl mice were fed high-fat diet (HFD) or LFD to generate obese and lean phenotypes, respectively. Obese mice were maintained on HFD or switched to LFD (HFD-LFD) or IER (HFD-IER). Ten weeks after induction of endometrial tumor, mice in each group received paclitaxel or placebo for 4 weeks. Body and tumor weights; tumoral transcriptomic, metabolomic and oxylipin profiles; and serum metabolic hormones and chemocytokines were assessed. ResultsHFD-IER and HFD-LFD, relative to HFD, reduced body weight; reversed obesity-induced alterations in serum insulin, leptin and inflammatory factors; and decreased tumor incidence and mass, often to levels emulating those associated with continuous LFD. Concurrent paclitaxel, versus placebo, enhanced tumor suppression in each group, with greatest benefit in HFD-IER. The diets produced distinct tumoral gene expression and metabolic profiles, with HFD-IER associated with a more favorable (antitumor) metabolic and inflammatory environment. ConclusionIn Lkb1fl/flp53fl/fl mice, IER is generally more effective than LFD in promoting weight loss, inhibiting obesity-related endometrial tumor growth (particularly in combination with paclitaxel), and reversing detrimental obesity-related metabolic effects. These findings lay the foundation for further investigations of IER as a EC prevention strategy in women with overweight/obesity.

cancer biology↗

Dorsal hippocampal oxytocin receptor regulates adult peer bonding in rats

Healthy social relationships are beneficial whereas their breakdown is often linked to psychiatric disorders. Parental care and bonding between sexual partners have been well studied both at the level of behavioral analysis and underlying neuronal mechanisms. By contrast, little is known about the neural and molecular basis of peer bonding, defined as social bonds formed between unrelated individuals of the same sex, due to the lack of a suitable experimental paradigm. We found that adult Sprague Dawley (SD) rats of the same sex form strong peer bonds with each other following co-housing. Peer bonded rats exhibit affiliative displays toward their cagemates who are distressed whereas they exhibit agonistic behaviors toward strangers in these situations. Using innovative, genetic strategies in rats, we show that both oxytocin receptor (OXTR) bearing neurons and Oxtr signaling in the dorsal hippocampus are essential for peer bonds to form. Together, we have developed a new platform for studying peer bonding and demonstrate a neural pathway that governs this behavior.

neuroscience↗

Prothoracicotropic hormone controls female sexual receptivity through the function of ecdysone in pC1 neurons of Drosophila

Female sexual receptivity is essential for reproduction of a species. Neuropeptides play the main role in regulating female receptivity. However, whether neuropeptides regulate female sexual receptivity during the neurodevelopment is unknown. Here we found the peptide hormone prothoracicotropic hormone (PTTH), which belongs to the insect PG axis, negatively regulated virgin female receptivity through ecdysone during neurodevelopment in Drosophila melanogaster. We identified PTTH neurons as doublesex-positive neurons, they regulated virgin female receptivity before the metamorphosis during the 3rd-instar larval stage. PTTH deletion resulted in the increased EcR-A expression in the whole newly formed prepupae. Furthermore, the ecdysone receptor EcR-A in pC1 neurons positively regulated virgin female receptivity during metamorphosis. The decreased EcR-A in pC1 neurons induced abnormal morphological development of pC1 neurons without changing neural activity. Among all subtypes of pC1 neurons, the function of EcR-A in pC1b neurons was necessary for virgin female copulation rate. These suggested that the changes of synaptic connections between pC1b and other neurons decreased female copulation rate. Moreover, female receptivity significantly decreased when the expression of PTTH receptor Torso was reduced in pC1 neurons. This suggested that PTTH not only regulates female receptivity through ecdysone but also through affecting female receptivity associated neurons directly. The PG axis has similar functional strategy as the HPG axis in mammals to trigger the juvenile-adult transition. Our work suggests a general mechanism underlying which the neurodevelopment during maturation regulates female sexual receptivity.

neuroscience↗

Conditional Chemoconnectomics: A Set of Libraries Targeting All Chemical Transmission Corresponding Genes Efficiently

Dissection of neural circuitry underlying behaviors is a central theme in neurobiology. We have previously proposed the concept of chemoconnectome (CCT) to cover the entire chemical transmission between neurons and target cells in an organize and created tools for studying it (CCTomics) by targeting all genes related to the CCT in Drosophila. Here we have created lines targeting the CCT in conditional manners after modifying GFP RNA interference, Flp-out and CRISPR/Cas9 technologies. All three strategies are validated to be highly effective with the best using chromatin-peptide fused Cas9 variants and scaffold optimized sgRNAs. As a proof of principle, we conduct a comprehensive intersection analysis of CCT genes expression profiles in the clock neurons, uncovering 43 CCT genes present in clock neurons. Specific elimination of each from clock neurons revealed that loss of the neuropeptide CNMa in two posterior dorsal clock neurons (DN1ps) or its receptor (CNMaR) caused advanced morning activity, indicating a suppressive role of CNMa-CNMaR on morning anticipation, opposite to the promoting role of PDF-PDFR on morning anticipation. These results demonstrate the effectiveness of conditional CCTomics and its tools created by us here and establish an antagonistic relationship between CNMa-CNMaR and PDF-PDFR signaling in regulating morning anticipation.

neuroscience↗

Mesenchymal stem cells of the bone marrow raise infectivity of Plasmodium falciparum gametocytes

Plasmodium falciparum is a parasite that causes the deadly human disease, malaria, and exhibits a complex life cycle in the human and mosquito hosts. As the sexual stages of the parasite, gametocytes mature in the human body and propagate malaria when they are picked up by mosquitoes to infect new hosts. Previous research has shown that gametocytes home to the bone marrow of the host where they complete their maturation and alter the behavior of resident Mesenchymal Stem Cells (MSCs). In this study, we investigated the alternate side of this host-pathogen interaction, whether MSCs could alter the behavior of gametocytes. Gametocytes were co-cultured with MSCs until maturity and subsequently fed to mosquitoes to measure the oocysts produced. Here we report for the first time, that MSCs co-culture significantly elevated oocyst numbers in the infected mosquito compared to conventional culture medium. This enhancement appeared to be most effective during the early stages of gametocyte development and was not replicated by other cell types. MSC co-culture also increased infectivity of field isolated P. falciparum parasites. This effect was partially mediated by soluble factor(s) as conditioned medium harvested from MSCs could also partially raise infectivity of gametocytes to nearly half compared to MSC co-culture. Together this study reveals novel host pathogen interactions, where the human MSCs are elevating the infectivity of malaria gametocytes. ImportanceWhile prior research has established that Plasmodium gametocytes sequester in the bone marrow and can influence resident stem cells, the question of why they would choose this compartment and these cells remained a mystery. This study for the first time, shows that being in the presence of MSCs alters the biology of the P. falciparum parasite and makes it more infectious to mosquitoes, hinting at novel mechanisms in its life cycle. This method also facilitates mosquito infections with field isolated parasites, affording research teams new infection models with parasite s which are challenging to infect into mosquitos using conventional culture methods. Finally, our findings that MSC conditioned medium can also raise infectivity opens avenues of investigation into mechanisms involved, but can also serve as a practical tool to researchers hoping to increase oocyst yields.

microbiology↗