Biology subjects

Lin, Y.

Publications and source records attributed to Lin, Y..

At least 199 records · Page 11Linked to original sources

bioRxiv2024

Enhancing Plant Photosynthesis using Carbon Dots as Light Converter and Photosensitizer

Improving photosynthetic efficiency is pivotal for CO2-based biomanufacturing and agriculture purposes. Despite the progress on photosynthetic biohybrids integrating biocatalysts with synthetic materials, nanomaterials with improved optical and photoelectrochemical properties are still needed to increase the energy-conversion efficiency. Here, we present a novel approach using carbon dots (CDs) as both intracellular photosensitizers and light converters for enhancing solar energy utilization in photosynthetic organisms. The CDs were produced from cyanobacterial biomass and used to convert a broad spectrum of solar irradiation to red light. We demonstrated that the nanosized CDs were incorporated into cyanobacterial cells and transferred light-excited electrons into the photosynthetic electron transfer chain. The biohybrids consisting of the CDs and Synechococcus elongatus exhibited increased growth rates, enhanced activities of both photosystems, and accelerated linear electron transport, compared with the cyanobacterial cells only. The supplementation of the CDs increased CO2-fixation rate and CO2-to-glycerol production by 2.4-fold and 2.2-fold, respectively. Furthermore, the CDs were shown to enhance photosynthesis and promote growth of Arabidopsis thaliana. The fresh weight of plant was increased 1.8-fold by CDs addition. These results reveal that simultaneous photosensitization and spectral modification could substantially improve the efficiency of natural photosynthesis. This study presents CDs as an attractive nanomaterial with great application potential in agriculture and solar-powered biomanufacturing.

synthetic biology↗

bioRxiv2024

CD40 Expression by B cells is Required for Optimal Immunity to Murine Pneumocystis Infection

CD40-CD40L interactions are critical for controlling Pneumocystis infection. However, which CD40-expressing cell populations are important for this interaction have not been well-defined. We used a cohousing mouse model of Pneumocystis infection, combined with flow cytometry and qPCR, to examine the ability of different populations of cells from C57BL/6 mice to reconstitute immunity in CD40 knockout (KO) mice. Unfractionated splenocytes, as well as purified B cells, were able to control Pneumocystis infection, while B cell depleted splenocytes and unstimulated bone-marrow derived dendritic cells (BMDCs) were unable to control infection in CD40 KO mice. Pneumocystis antigen-pulsed BMDCs showed early, but limited, control of infection. Consistent with recent studies that have suggested a role for antigen presentation by B cells, using cells from immunized animals, B cells were able to present Pneumocystis antigens to induce proliferation of T cells. Thus, CD40 expression by B cells appears necessary for robust immunity to Pneumocystis.

microbiology↗

bioRxiv2024

A multiple Arc (mArc) tagging system to uncover the organizational principles of multiple memories

Engrams or memory traces are the neuronal ensembles that collectively store individual experiences. Genetic strategies based on immediate early genes (IEGs), such as Arc/Arg3.1, allow us to tag the ensembles active during memory encoding and compare them to those active during retrieval. However, these strategies only allow for the tagging of one neural ensemble. Here, we developed a multiple Arc (mArc) system that allows for the tagging of two Arc+ ensembles. We validated this system by investigating how context, time, and valence influence neuronal ensemble reactivation in the dentate gyrus (DG). We show that similar contextual and valenced experiences are encoded in overlapping DG ensembles. We also find that ensembles are modulated by time, where experiences closer in time are encoded in more similar ensembles. These results highlight the dynamic nature of DG ensembles and show that the mArc system provides a powerful approach for investigating multiple memories in the brain. HIGHLIGHTSO_LIThe mArc system allows for the tagging of two Arc+ ensembles in the same mouse C_LIO_LIDG ensembles labeled by the mArc system receive increased excitatory input C_LIO_LIContext, valence, and time influence DG ensemble reactivation C_LIO_LIDG neural ensembles are reactivated less with increasing time C_LI

neuroscience↗

bioRxiv2024

Proximity labeling proteomics reveals Kv1.3 potassium channel immune interactors in microglia.

Microglia are the resident immune cells of the brain and regulate the brains inflammatory state. In neurodegenerative diseases, microglia transition from a homeostatic state to a state referred to as disease associated microglia (DAM). DAM express higher levels of proinflammatory signaling, like STAT1 and TLR2, and show transitions in mitochondrial activity toward a more glycolytic response. Inhibition of Kv1.3 decreases the proinflammatory signature of DAM, though how Kv1.3 influences the response is unknown. Our goal was to establish the potential proteins interacting with Kv1.3 during the TLR4-mendiated transition to DAM. We utilized TurboID, a biotin ligase, fused to Kv1.3 to evaluate the potential interacting proteins with Kv1.3 via mass spectrometry in BV-2 microglia during an immune response. Electrophysiology, western blots, and flow cytometry were used to evaluate Kv1.3 channel presence and TurboID biotinylation activity. We hypothesized that Kv1.3 contains domain-specific interactors that vary during an TLR4-induced inflammatory response, some of which are dependent on the PDZ-binding domain on the C-terminus. We determined that the N-terminus of Kv1.3 is responsible for trafficking Kv1.3 to the cell surface and mitochondria (e.g. NUNDC, TIMM50). The C-terminus interacts with immune signaling proteins in an LPS-induced inflammatory response (e.g. STAT1, TLR2, and C3). There are 70 proteins that rely on the c-terminal PDZ-binding domain to interact with Kv1.3 (i.e. ND3, Snx3, and Sun1). Overall, we highlight that the Kv1.3 potassium channel functions beyond outward flux of potassium in an inflammatory context and contributes to activity of key immune signaling proteins, such as STAT1 and C3. MAIN POINTSKv1.3 channels are highly abundant in pro-inflammatory microglia in neurological diseases. Kv1.3 channels may regulate microglial functions by interacting with other proteins via its N and C terminal domains. Using proximity-based proteomics, we identified several novel proteins that interact with the N and C terminus of Kv1.3 channels, some of which are domain-specific. Kv1.3 channels in microglia interact with many immune signaling proteins, including Tlr2, Stat1 and integrins. Under homeostatic conditions, the N-terminus of Kv1.3 interacts with proteins involved in protein trafficking, to the cell surface and mitochondria. The PDZ-binding region was an important determinant of the C terminal interactome. During an LPS-induced inflammatory response, the C-terminus of Kv1.3 uniquely interacts with immune and signaling proteins of disease relevance, including STAT1

neuroscience↗

bioRxiv2024

Scale-Dependent Coding of the Hippocampus in Relational Memory

Memory, woven into the very fabric of consciousness, serves as a time-traveling vessel in the mind, using detailed recollections not just for nostalgic reflection but as an abstract map for charting unknown futures. Here, we employed fMRI to investigate how the hippocampus (HPC) encodes detailed experiences into abstract knowledge (i.e., formation) and uses this knowledge for decision making (i.e., utilization) when human participants learned and then utilized spatial-temporal relations in a relational memory task. We found a functional gradient along the anterior-posterior axis of the HPC, characterized by representational similarity and functional connectivity with the autobiographical network. Here, the posterior HPC was more actively engaged in memory formation, whereas the anterior HPC was predominantly involved in memory utilization. Our computational modeling of relational memory further established a causal link between this functional gradient and the HPCs well-documented anatomical gradient, as optimal task performance arose from a combination of a fine-grained representation of past experiences by the posterior HPC and a coarser representation of abstract knowledge for future planning by the anterior HPC. This scale-dependent coding scheme led to the emergence of grid-like, heading direction-like, and place-like units in our neural network model, analogous to those discovered in biological brains. Taken together, our study revealed the HPCs functional gradient in representing relational memory, and further connected it to the anatomical gradient of place cells, supporting a unified framework where both spatial and episodic memory rely on relational representations that integrate spatial localization with temporal continuity.

neuroscience↗

bioRxiv2024

Single-cell RNA sequencing of iPSC-derived brain organoids reveals Treponema pallidum infection inhibiting neurodevelopment

Congenital syphilis is a vertically transmitted bacterial infection caused by Treponema pallidum, often causing multidomain neurodevelopmental disabilities. However, little is known about the pathogenesis of this disease. Brain organoids platform derived from the induced pluripotent stem cell (iPSC) is exposed to T. pallidum infection for modelling congenital neurodevelopmental impairment. Single-cell RNA sequencing is used for identifying the subpopulations of differentially expressed genes and cellular heterogeneity and reconstructing differentiation trajectories following T. pallidum infection. The results reveal that T. pallidum infection influences the formation of neural rosette structures, reduces the cell number of the neural progenitor cell subcluster 1B (subNPC1B) and hindbrain neurons, and affects the neurodevelopment of the brain organoid. Moreover, it is speculated that T. pallidum inhibits the hindbrain neuron cell number through the suppression of subNPC1B subgroup in the organoids and inhibits transcription factor 3 activity in the subNPC1B-hindbrain neuronal axis. This is the first report on the inhibited effects of T. pallidum on the neurodevelopment of the iPSC-derived brain organoid model. T. pallidum could inhibit the differentiation of subNPC1B in brain organoids, thereby reducing the differentiation from subNPC1B to hindbrain neurons, and ultimately affecting the development and maturation of hindbrain neurons.

neuroscience↗

bioRxiv2024

A functional medicine and food homology composition discovery based on disease-related target and data mining against cardiac remodeling

BackgroundMedicine and food homological (MFH) products exhibit enhanced safety and tolerability, minimizing notable side effects, making them pivotal for prolonged use in cardiovascular diseases. This study aims to identify functional compounds in MFH based on cardiac remodeling-related target, employing reliable, comprehensive, and high-throughput methods. MethodsBy bioinformatics and in vivo verifications, we initially investigated the key target in the progression of cardiac remodeling. Subsequently, we performed molecular docking among medical homology compound database (MHCD), and then performed drug-likeness evaluations to recognize functional component based on disease-related target. Pharmacological verifications and data mining including cardiac and medullary transcriptomics, neurotransmitter metabolomics, resting-state functional magnetic resonance imaging (rs-fMRI), and correlationship analysis were utilized to define the benefical effects of MFH functional components, as well as its in-depth mechanims. ResultsThe critical roles of oxidative stress and the key target of NRF2 in cardiac remodeling were discovered, and {beta}-ecdysterone was screened as the most promising NRF2 enhancer in MHCD. Dose-dependent efficacy of {beta}-ecdysterone in countering oxidative stress and ameliorating cardiac remodeling were then verfied by in vivo and ex vivo experiments. By data mining, the crosstalk mechanism between cardiac remodeling and neuromodulation was identified, and further unveiled Slc41a3 as a potential key factor influenced by {beta}-ecdysterone. Additionally, {beta}-ecdysterone mitigated increases in norepinephrine (NE) and its metabolites DHPG in the sympathetic nerve center hypothalamic paraventricular (PVN), as indicated by rs-fMRI. Cardiac and medullary transcriptomes revealed central-peripheral regulation signaling pathways during cardiac remodeling with the involvement of core gene of Dhx37. ConclusionsOur study identified {beta}-ecdysterone as a natural MFH functional compound countering cardiac remodeling by targeting NRF2 elevation. It elucidates crosstalk between cardiac remodeling and neuromodulation, facilitating precise drug screening and mechanistic insights, providing substantial evidence for {beta}-ecdysterone application and molecular mechanisms in cardiovascular diseases.

pharmacology and toxicology↗

bioRxiv2024

Signaling events at TMEM doorways provide potential targets for inhibiting breast cancer dissemination

Tumor cell intravasation is essential for metastatic dissemination, but its exact mechanism is incompletely understood. We have previously shown that in breast cancer, the direct and stable association of a tumor cell expressing Mena, a Tie2hi/VEGFhi macrophage, and a vascular endothelial cell, creates an intravasation portal, called a "tumor microenvironment of metastasis" (TMEM) doorway, for tumor cell intravasation, leading to dissemination to distant sites. The density of TMEM doorways, also called TMEM doorway score, is a clinically validated prognostic marker of distant metastasis in breast cancer patients. Although we know that tumor cells utilize TMEM doorway-associated transient vascular openings to intravasate, the precise signaling mechanisms involved in TMEM doorway function are only partially understood. Using two mouse models of breast cancer and an in vitro assay of intravasation, we report that CSF-1 secreted by the TMEM doorway tumor cell stimulates local secretion of VEGF-A from the Tie2hi TMEM doorway macrophage, leading to the dissociation of endothelial junctions between TMEM doorway associated endothelial cells, supporting tumor cell intravasation. Acute blockade of CSF-1R signaling decreases macrophage VEGF-A secretion as well as TMEM doorway-associated vascular opening, tumor cell trans-endothelial migration, and dissemination. These new insights into signaling events regulating TMEM doorway function should be explored further as treatment strategies for metastatic disease.

cancer biology↗

bioRxiv2024

Spatiotemporal Mapping and Molecular Basis of Whole-brain Circuit Maturation

Brain development is highly dynamic and asynchronous, marked by the sequential maturation of functional circuits across the brain. The timing and mechanisms driving circuit maturation remain elusive due to an inability to identify and map maturing neuronal populations. Here we create DevATLAS (Developmental Activation Timing-based Longitudinal Acquisition System) to overcome this obstacle. We develop whole-brain mapping methods to construct the first longitudinal, spatiotemporal map of circuit maturation in early postnatal mouse brains. Moreover, we uncover dramatic impairments within the deep cortical layers in a neurodevelopmental disorders (NDDs) model, demonstrating the utility of this resource to pinpoint when and where circuit maturation is disrupted. Using DevATLAS, we reveal that early experiences accelerate the development of hippocampus-dependent learning by increasing the synaptically mature granule cell population in the dentate gyrus. Finally, DevATLAS enables the discovery of molecular mechanisms driving activity-dependent circuit maturation.

neuroscience↗

bioRxiv2023

TaNF-Y-PRC2 orchestrates temporal control of starch and protein synthesis in wheat

The endosperm in cereal grains is instrumental in determining grain yield and seed quality, as it controls the production of starch and protein. In this study, we identified a specific TaNF-Y trimeric complex, consisting of TaNF-YA3-D, TaNF-YB7-B, and TaNF-YC6-B, exhibiting robust expression within endosperm during grain filling stage in wheat. Knock-down of either TaNF-YA3 or TaNF-YC6 led to less starch but more gluten proteins. Detailed analyses have unveiled that the TaNF-Y indirectly boosts starch biosynthesis genes by reducing TaNAC019, a repressor of TaAGPS1a, TaSuS2, thereby regulating starch biosynthesis. Conversely, the TaNF-Y directly inhibits the expression of gliadin and low molecular weight (LMW)-GS coding genes, including TaGli-{gamma}-700 and TaLMW-400. Furthermore, the TaNF-Y components interact with TaSWN, the histone methyltransferase subunit of Polycomb repressive complex 2 (PRC2), to repress the expression of TaNAC019, TaGli-{gamma}-700, and TaLMW-400 through H3K27me3 modification. Notably, weak mutation of TaFIE, core subunit of PRC2, has reduced starch but elevated gliadin and LMW-GS levels. Intriguingly, DNA variations of TaNF-Y components are widely associated with seed developmental traits. In particular, variation within the coding region of TaNF-YB7-B is linked to differences in starch and protein content. Distinct haplotypes of TaNF-YB7-B affect its interaction with TaSWN, influencing the repression of targets like TaNAC019 and TaGli-{gamma}-700. Our findings illuminate the intricate molecular mechanisms governing epigenetic regulation by the TaNF-Y-PRC2 for wheat endosperm development. Manipulating the TaNF-Y complex holds potential for optimizing grain yield and enhancing quality.

plant biology↗

bioRxiv2023

The current landscape and emerging challenges of benchmarking single-cell methods

With the rapid development of computational methods for single-cell sequencing data, benchmarking serves as a valuable resource. As the number of benchmarking studies surges, it is timely to assess the current state of the field. We conducted a systematic literature search and assessed 282 papers, including all 130 benchmark-only papers from the search and an additional 152 method development papers containing benchmarking. This collective effort provides the most comprehensive quantitative summary of the current landscape of single-cell benchmarking studies. We examine performances across nine broad categories, including often ignored aspects such as role of datasets, robustness of methods and downstream evaluation. Our analysis highlights challenges such as how to effectively combine knowledge across multiple benchmarking studies and in what ways can the community recognise the risk and prevent benchmarking fatigue. This paper highlights the importance of adopting a community-led research paradigm to tackle these challenges and establish best practice standards.

bioinformatics↗

bioRxiv2023

Parallel Molecular Data Storage by Printing Epigenetic Bits on DNA

DNA storage has shown potential to transcend current silicon-based data storage technologies in storage density, lifetime and energy consumption. However, writing large-scale data directly into DNA sequences by de novo synthesis remains uneconomical in time and cost. Inspired by the natural genomic modifications, in this work, we report an alternative, parallel strategy that enables the writing of arbitrary data on DNA using premade nucleic acids. With epigenetic modifications as information bits, our system employed DNA self-assembly guided enzymatic methylation to perform movable-type printing on universal DNA templates. By programming with a finite set of 700 DNA movable types and 5 templates, we achieved the synthesis-free writing of [~]270000 bits on an automated platform with 350 bits written per reaction. The data encoded in complex epigenetic patterns were retrieved high-throughput by nanopore sequencing, and algorithms were developed to finely resolve 240 modification patterns per sequencing reaction. Our framework presents a new modality of DNA-based data storage that is parallel, programmable, stable and scalable. Such a modality opens up avenues towards practical data storage and dual-mode data functions in biomolecular systems.

biochemistry↗

bioRxiv2023

Scm6A: A fast and low-cost method for quantifying m6A modifications at the single-cell level

It is widely accepted that m6A exhibits significant intercellular specificity, which poses challenges for its detection using existing m6A quantitative methods. In this study, we introduce Scm6A, a machine learning-based approach for single-cell m6A quantification. Scm6A leverages input features derived from the expression levels of m6A trans regulators and cis sequence features, and found that Scm6A offers remarkable prediction efficiency and reliability. To further validate the robustness and precision of Scm6A, we applied a winscore-based m6A calculation method to conduct m6A-seq analysis on CD4+ and CD8+ T-cells isolated through magnetic-activated cell sorting (MACS). Subsequently, we employed Scm6A for analysis on the same samples. Notably, the m6A levels calculated by Scm6A exhibited a significant positive correlation with m6A quantified through m6A-seq in different cells isolated by MACS, providing compelling evidence for Scm6As reliability. We also used the scm6A-seq method to validate the reliability of our approach. Additionally, we performed single-cell level m6A analysis on lung cancer tissues as well as blood samples from COVID-19 patients, and demonstrated the landscape and regulatory mechanisms of m6A in different T-cell subtypes from these diseases. In summary, our work has yielded a novel, dependable, and accurate method for single-cell m6A detection. We are confident that Scm6A will have broad applications in the realm of m6A-related research.

bioinformatics↗

bioRxiv2023

Pan-cancer Analysis Reveals m6A Variation and Cell-specific Regulatory Network in Different Cancer Types

As the most abundant mRNA modification in mRNA, N6-methyladenosine (m6A) plays a crucial role in RNA fate, impacting cellular and physiological processes in various tumor types. However, our understanding of the function and role of the m6A methylome in tumor heterogeneity remains limited. Herein, we collected and analyzed m6A methylomes across nine human tissues from 97 m6A-seq and RNA-seq samples. Our findings demonstrate that m6A exhibits different heterogeneity in most tumor tissues compared to normal tissues, which contributes to the diverse clinical outcomes in different cancer types. We also found that the cancer type-specific m6A level regulated the expression of different cancer-related genes in distinct cancer types. Utilizing a novel and reliable method called "m6A-express", we predicted m6A- regulated genes and revealed that cancer type-specific m6A-regulated genes contributed to the prognosis, tumor origin and infiltration level of immune cells in diverse patient populations. Furthermore, we identified cell-specific m6A regulators that regulate cancer-specific m6A and constructed a regulatory network. Experimental validation was performed, confirming that the cell-specific m6A regulator CAPRIN1 controls the m6A level of TP53. Overall, our work reveals the clinical relevance of m6A in various tumor tissues and explains how such heterogeneity is established. These results further suggest the potential of m6A for cancer precision medicine for patients with different cancer types.

bioinformatics↗

bioRxiv2023

Differential developmental blueprints of organ-intrinsic nervous systems

The organ-intrinsic nervous system is a major interface between visceral organs and the brain, mediating important sensory and regulatory functions in the body-brain axis and serving as critical local processors for organ homeostasis. Molecularly, anatomically, and functionally, organ-intrinsic neurons are highly specialized for their host organs. However, the underlying mechanism that drives this specialization is largely unknown. Here, we describe the differential strategies utilized to achieve organ-specific organization between the enteric nervous system (ENS)1 and the intrinsic cardiac nervous system (ICNS)2, a neuronal network essential for heart performance but poorly characterized. Integrating high-resolution whole-embryo imaging, single-cell genomics, spatial transcriptomics, proteomics, and bioinformatics, we uncover that unlike the ENS which is highly mobile and colonizes the entire gastrointestinal (GI) tract, the ICNS uses a rich set of extracellular matrix (ECM) genes that match with surrounding heart cells and an intermediate dedicated neuronal progenitor state to stabilize itself for a beads-on-the-necklace organization on heart atria. While ICNS- and ENS-precursors are genetically similar, their differentiation paths are influenced by their host-organs, leading to distinct mature neuron types. Co-culturing ENS-precursors with heart cells shifts their identity towards the ICNS and induces the expression of heart-matching ECM genes. Our cross-organ study thus reveals fundamental principles for the maturation and specialization of organ-intrinsic neurons.

neuroscience↗

bioRxiv2023

Unraveling the Phenotypic States of Human innate-like T Cells: Comparative Insights with Conventional T Cells and Mouse Models

The "innate-like" T cell compartment, known as Tinn, represents a diverse group of T cells that straddle the boundary between innate and adaptive immunity, having the ability to mount rapid responses following activation. In mice, this ability is acquired during thymic development. We explored the transcriptional landscape of Tinn compared to conventional T cells (Tconv) in the human thymus and blood using single cell RNA sequencing and flow cytometry. We reveal that in human blood, the majority of Tinn cells, including iNKT, MAIT, and V{delta}2+V{gamma}9+ T cells, share an effector program characterized by the expression of unique chemokine and cytokine receptors, and cytotoxic molecules. This program is driven by specific transcription factors, distinct from those governing Tconv cells. Conversely, only a fraction of thymic Tinn cells displays an effector phenotype, while others share transcriptional features with developing Tconv cells, indicating potential divergent developmental pathways. Unlike the mouse, human Tinn cells do not differentiate into multiple effector subsets but develop a mixed type I/type III effector potential. To conduct a comprehensive cross-species analysis, we constructed a murine Tinn developmental atlas and uncovered additional species-specific distinctions, including the absence of type II Tinn cells in humans, which implies distinct immune regulatory mechanisms across species. The study provides insights into the development and functionality of Tinn cells, emphasizing their role in immune responses and their potential as targets for therapeutic interventions.

immunology↗

bioRxiv2023

Golgi-associated retrograde protein (GARP) complex recruits retromer to trans-Golgi network for FgKex2 and FgSnc1 recycling, necessary for development and pathogenicity of Fusarium graminearum

In eukaryotic cells, the retromer complex plays a crucial role in orchestrating the sorting and retrograde transport of cargo proteins from endosomes to the trans-Golgi network (TGN). Despite its significance, the molecular details of this intracellular trafficking process remain unclear. Here, we identified a Golgi-associated retrograde protein (GARP) complex as a mediator of vesicular transport, facilitating the recruitment of the retromer complex to TGN to exert its functions. The GARP complex is mainly localized to the TGN, where it interacts with the retromer complex. This interaction is evolutionarily conserved across different species. Furthermore, we identified FgKex2 and Fgsnc1 as cargo proteins in the GARP/retromer-mediated recycling pathway. Loss of GARP or retromer results in a complete mis-sorting of FgKex2 and FgSnc1 to the vacuolar degradation pathway, which affects the growth, development, toxisome biogenesis, and pathogenicity of F. graminearum. In summary, we assert that GARP facilitates the recruitment of retromer from endosomes to the TGN, orchestrating the recycling of FgKex2 and FgSnc1. This is integral to sustaining continuous growth, development and contributes significantly to the pathogenicity of F. graminearum.

microbiology↗

bioRxiv2023

Remote memory engrams are controlled by encoding-specific tau phosphorylation

The engram represents the physical trace that encodes a specific memory and enables its recall 1-4. Functional failure of the engram is linked to the progressive memory decline in Alzheimers disease 5. However, it is unknown whether the microtubule-associated protein tau, a central factor in Alzheimers 6,7, has a direct function in the engram. Here, we demonstrate that tau and encoding-associated tau phosphorylation are critical for robust remote memory engrams. Tau is required specifically during memory formation for remote, yet not proximal recall in memory paradigms in mice. Controlled expression of tau exclusively during memory entrainment is necessary and sufficient to restore remote memory deficits in tau knockout mice. Tau is phosphorylated at specific sites during encoding. Gene editing to ablate site-specific phosphorylation at threonine-205 (T205) lowers precision of engram cell recruitment and precludes efficient remote recall. Vector-based engineering of engram cells reveals that T205 phosphorylation of tau is required to engrain memory for recall at remote timepoints. Notably, in the absence of tau, memory is recalled from latency by direct optogenetic activation of engram cells at distal time points but not when natural cues are used, revealing an association-specific gatekeeper function of tau during encoding. Our work delineates a physiologic role of site-specific tau phosphorylation at the inception of episodic memory to support an enduring engram and enable efficient remote recall. Thus, encoding-associated phosphorylation of tau is proximal to the elusive substrate of remote memory and may connect to the basis of amnesia in Alzheimers disease.

neuroscience↗