Biology subjects

Hu, D.

Publications and source records attributed to Hu, D..

At least 19 recordsLinked to original sources

bioRxiv2026

Heterochronic Uncoupling of Brain and Face Morphogenesis Drives Premature Fusion in Ciliary Transition Zone Mutants

Normal facial development is highly coordinated with embryonic brain expansion, suggesting the forebrain acts as a physical scaffold dictating the spatial timing of facial prominence apposition and fusion. To test this idea, we compared B9d1 ciliary transition zone mutants, which exhibit altered Hedgehog signaling and premature facial fusion, to a normal murine developmental morphospace. At e11.5, mutant brains are significantly reduced in size, yet intrinsic facial prominence size remains largely normal. Projecting e11.5 and e12.5 mutants into the normal morphospace reveals a severe heterochronic uncoupling: the delayed, narrowed neurocranium mechanically forces normal-sized facial prominences into premature convergence. These results indicate that when brain growth slows, facial prominences initiate contact earlier in restricted spatial bounds. Conversely, this model predicts that an accelerated, expanded brain may act as a physical wedge, increasing the likelihood of cleft lip. By mathematically modeling these structural dependencies, we propose that palatogenesis operates on a continuous phenotypic spectrum, where premature fusion and cleft lip represent alternative physical outcomes conditioned on the underlying brain developmental trajectory.

developmental biology↗

bioRxiv2026

Three-hinge gyri link individualized folding topology to cortical and superficial white-matter diffusion organization

Individual differences in cortical folding are a hallmark of human brain anatomy, but what this variability reflects in the underlying tissue remains unclear. Three-hinge gyri (3HGs), where three gyral crests converge, provide an individualized higher-order folding landmark for probing this relationship. Using 7T diffusion MRI in six postmortem hemispheres, we found lower mean, axial, and radial diffusivity and higher fractional anisotropy at 3HGs than at matched gyral crowns, with the principal tensor pattern replicated in 414 age-matched in vivo adults. Diffusivity differences extended across the cortical ribbon, whereas anisotropy- and fiber-related differences strengthened toward and beneath the white surface. Ex vivo, diffusion measures also varied with gyral-skeleton degree, and streamlines sampled beneath 3HGs preferentially reached other 3HGs. These findings link individualized folding topology to cortical and superficial white-matter diffusion-inferred tissue properties, providing tissue-level context for understanding the microstructural correlates of individual folding variation.

neuroscience↗

bioRxiv2026

Navigating the window: structural bottlenecks in avian craniofacial integration revealed by the ontogenetic patterning of shape variance

Background: Successful palatal morphogenesis requires the precise spatiotemporal choreography of independent facial prominences. Our previous macroevolutionary analyses identified a convergence in amniote facial growth at primary palatal fusion, associated with reduced shape variability. We hypothesize that this constraint operates within individual species, representing a shared structural bottleneck where brain growth acts as a critical morphogenetic co-factor. To test this idea, we analyzed high-resolution 3D micro-CT images of embryonic chickens (Gallus gallus, N=217) spanning primary palatogenesis. Utilizing 3D geometric morphometrics (3DGM), we quantified a continuous "developmental morphospace" integrating the face and brain. Results: Facial shape follows a highly nonlinear developmental trajectory. Using a continuous sliding-window analysis, we demonstrate that local morphological disparity undergoes a significant system-wide collapse coinciding with primary palatal fusion. Partial Least Squares (PLS) confirms this morphospace pivot is tightly coordinated with neurocranial development. Post-fusion, the modules uncouple: facial allometry switches from convergent to divergent projecting growth, while the brain undergoes spatial encapsulation, subsequently flatlining its morphological disparity. Conclusions: Craniofacial morphogenesis can be described in terms of a tightly regulated biphasic developmental hourglass. The physical tethering of facial prominences creates a brief structurally constrained "shape window" essential for successful fusion. Deviations from this bottleneck, whether driven by altered prominence trajectories, increased local variance, or disruptions to the underlying forebrain landscape, push embryos into unoccupied morphospace, providing a unified mechanical and predictive framework for the spatiotemporal origins of non-syndromic cleft lip.

developmental biology↗

bioRxiv2026

Division-Specific Organization of a Shared Functional Scaffold in the Early-Life Human Brain

Early cognition and behavior emerge from coordinated maturation of functional systems spanning the brain, making cross-division integration essential for defining whole-brain architecture and understanding its role in neurodevelopment. Yet early human functional development is still largely investigated through cortical networks or through isolated, coarsely resolved noncortical structures, leaving unclear how this integrated architecture is organized across the cerebral cortex, subcortex and cerebellum. Moving beyond structure-isolated and adult-derived maps, we create a reproducible, fine-grained Early-Life Whole-Brain Functional Parcellation (UNC-ELF) spanning birth to six years. Using this framework, we identify a shared functional scaffold expressed through distinct division-specific modes: differentiated and dual-polarity cortical organization, spatially graded cerebellar organization with blended functional transition zones, and nucleus-constrained subcortical mosaics of multi-system affiliation. Across early childhood, the scaffold is selectively refined through heterogeneous, nonlinear connectivity trajectories, with major inflections concentrated in infancy. Age-, sex- and prospective cognition-related variation is differentially encoded across distinct connectomic components. Together, these findings reframe early functional brain development as coordinated refinement of a shared but nonuniform whole-brain scaffold and establish UNC-ELF as a unified reference for resolving typical and atypical functional organization across the developing brain.

neuroscience↗

bioRxiv2026

SLIM: A small linear model with STRING embeddings for single-cell genetic perturbation prediction

Predicting cellular responses to genetic perturbations is central to understanding gene function and prioritizing therapeutic targets, but experimental screens cannot exhaustively cover genes, cell types, and perturbation combinations. Recent benchmarks have shown that simple baselines can match or outperform substantially more complex models, suggesting that informative biological priors may be as important as model capacity. Here we present SLIM, a lightweight extension of the bilinear model of Ahlmann-Eltze et al. SLIM represents perturbations with 64-dimensional embeddings derived from the STRING protein network and predicts mean transcriptional responses through a closed-form ridge-regression estimator. It then constructs single-cell populations by retrieving training cells and rescaling each gene to match the predicted mean. We evaluated SLIM against four deep learning models and two simple baselines on four single-gene perturbation datasets and one combinatorial perturbation dataset. Across these within-dataset benchmarks, SLIM achieved competitive mean-response accuracy, ranked first in eight of twelve single-gene dataset-metric comparisons, and produced substantially lower maximum mean discrepancy values than the evaluated alternatives. The model has 640 trainable parameters and fitted each benchmark dataset in under 10 seconds on a CPU. These results show that compact biological representations can support accurate and computationally efficient perturbation prediction. Code is available at https://github.com/RasmussenLab/SLIM. Key PointsO_LISLIM combines a closed-form bilinear predictor with STRING-derived perturbation embeddings. C_LIO_LIAcross five within-dataset benchmarks, SLIM achieved competitive mean-response prediction with only 640 trainable parameters. C_LIO_LISLIM builds cell populations by rescaling retrieved training cells to the predicted mean, so they inherit realistic cell-to-cell variation and gene-gene covariation. C_LIO_LIThe results highlight the importance of perturbation representations and population-construction procedures in low-data benchmarks. C_LIO_LISLIM fits each benchmark dataset in under 10 seconds on a standard CPU. C_LI

bioinformatics↗

bioRxiv2026

Iterative co-creation of harmonized human and non-human primate cellular and structural ontologies and 3D common coordinate frameworks for the basal ganglia

A major goal of the BRAIN Initiative Cell Atlas Network (BICAN) is to create a suite of foundational reference cell atlases and associated standards for human and non-human primate brains. Central to this goal is the creation of cross-species harmonized cellular taxonomies and structural parcellations with formal ontologies that can be mapped into 3D reference frameworks bridging neuroimaging and cellular and histological resolutions. We describe here an iterative approach, focused initially on the basal ganglia, to co-create structural and cellular ontologies in human, macaque and marmoset brains, including a Harmonized Ontology of Mammalian Brain Anatomy (HOMBA), and to map and refine structural parcellations into neuroimaging-based common coordinate frameworks. These references provide the framework for documenting and mapping all experimental sampling in BICAN, allowing analyses of cellular and molecular variation as a function of topographic position, and enabling comparisons of cellular, molecular and neuroimaging-based functional variation within and between primate species. HighlightsO_LIA hierarchical Harmonized Ontology of Mammalian Brain Anatomy (HOMBA) covering 2348 structures C_LIO_LIHOMBA-annotated 3D common coordinate frameworks (CCFs) of the basal ganglia across species C_LIO_LIHistologically informed 3D parcellation/atlas of 280 human subcortical structures indexed by HOMBA C_LIO_LIMapping and integration of structural, cellular and functional data with HOMBA and CCFs C_LI

neuroscience↗

bioRxiv2026

A pyramidal silicon nanopore for single misfolded Tau protein characterisation

Solid-state nanopores offer a versatile platform for single-molecule sensing owing to their mechanical robustness, tuneable geometry, and compatibility with scalable fabrication. Here, we present a pyramidal silicon nanopore with a 40 nm sensing aperture for label-free characterisation of protein molecules by resistive pulse sensing. The nanopore operates stably over transmembrane voltages ranging from -2 to +2 V and across a broad range of electrolyte concentrations, enabling analysis under diverse experimental conditions. As molecules traverse the confined sensing region, transient ionic current modulations are generated that reflect their excluded volume and molecular geometry. Using this approach, we characterise unlabelled Tau species spanning monomeric proteins, intermediate aggregates, and mature fibrillar assemblies. Analysis of the resulting current signatures, together with simplified geometrical models, enables reconstruction of molecular dimensions and discrimination of distinct Tau populations based on their electrical fingerprints. These results demonstrate that pyramidal silicon nanopores provide a sensitive and scalable platform for label-free monitoring of structurally heterogeneous protein aggregation and establish a framework for investigating protein aggregation using solid-state nanopore sensing.

bioengineering↗

bioRxiv2026

Angiogenesis Guided by Bombyx mori Silk Proteins is Molecular Weight-Dependent

Silk proteins, including sericin and fibroin, are natural biopolymers with broad applications in tissue engineering where angiogenesis plays an essential role. However, the pro-angiogenic effects of silk proteins with varying molecular weights (MWs) remain poorly understood. Here, silk proteins with MW distributions at 40-180 kDa or less than 25 kDa were obtained through alkaline hydrolysis to evaluate their effects on angiogenesis. Structurally, reducing MW induced a conformational transition in silk proteins, accompanied by a striking morphological shift in sericin from nanofibers to nanoparticles. Functionally, high-MW sericin (SSH) suppressed, whereas low-MW sericin (SSL) and both high- and low-MW silk fibroin (SFH/SFL) directly promoted endothelial angiogenic activity. Transcriptomic analysis revealed that angiogenesis-related genes such as Id1 and Smad6/9 may underlie the angiostatic effects of SSH. Notably, both SSH and SSL enhanced angiogenesis indirectly via macrophages; however, SSH induced mixed M1/M2-like polarization, while SSL preferentially drove an M2-like phenotype. In a subcutaneous implantation model, SSH promoted angiogenesis but yielded vessels with weak integrity and increased fibrosis, whereas SSL enhanced angiogenesis with improved vascular maturity and reduced fibrotic response. These findings elucidate how the MWs of silk proteins shape angiogenic behavior and highlight the importance of MW tailoring for optimized tissue engineering applications.

Cell Biology↗

bioRxiv2026

NKG2C+CD27- Defines Human CD8+ Regulatory T Cells

Here we identify NKG2C+CD27- as a novel surface marker unifying multiple previously reported CD8+ regulatory T cell (Treg) populations. This population displays high clonality and divides into CD226- (Treg1) and CD226+ (Treg2) subsets, with Treg2 exhibiting stronger suppressive activities. Up to 35% of CD8+ TEMRA cells are Tregs, whereas approximately 85% of CD8+ Tregs are TEMRA cells, which increase with aging. These findings establish a unified and novel cell surface marker for CD8+ Tregs and their subsets, which resolves prior heterogeneity in the field, and show that CD8+ TEMRA cells are a heterogeneous population that includes T cells with regulatory function. Our findings provide a critical framework for the isolation and in-depth functional characterization of CD8+ Tregs in health, aging, and disease.

immunology↗

bioRxiv2026

Culture-enriched metagenomics enables genome-resolved detection of low abundance ESKAPE and Vibrio pathogens in coastal habitats

Coastal marine environments are increasingly recognised as reservoirs of antimicrobial-resistant (AMR) pathogens. However, it remains challenging to recover high-quality genomes of clinically relevant bacteria present at low abundance from complex natural systems. Here, we applied culture-enriched metagenomics to systematically track the diversity and dynamics of major AMR pathogens within the coastal marine system of St. Johns Island, Singapore, as a model ecosystem for pathogen surveillance. Selective media-based enrichment recovered 773 metagenome-assembled genomes (MAGs) from 92 multi-matrix environmental samples, which includes coastal water, sediment, and seaweed, capturing diverse AMR ESKAPE and Vibrio species. Distinct bacterial signatures and dispersal patterns were observed in each niche, for example, microbes that signal human impact was detected at the beach, while fish-associated pathogens were present at the aquaculture facility outlet. Notably, the high-quality MAGs enabled subspecies-level identification and supported the AMR gene detection across six distinct coastal habitats. Detailed differences in the recovery of specific pathogens across enrichment media were also identified, demonstrating the methods efficacy in finding media suitable for surveillance of specific organisms, such as deciding between liquid or solid formulations. MAGs recovered from culture-enriched metagenomics were highly similar to genomes obtained from pure isolates, as demonstrated for Klebsiella pneumoniae. The preserved culture-enriched stocks were capable of recovering organisms of interest when individual isolates were required for further study. Overall, our findings highlight the utility of culture-enriched metagenomics as a cost-effective, sensitive approach to uncovering the genomic landscape of pathogens with environmental reservoirs, with implications for AMR surveillance and ecological risk assessment.

microbiology↗

bioRxiv2026

Who and how much? Quantifying the role of trophic guilds in soil organic carbon mineralization

Understanding the biotic processes that drive soil organic carbon (SOC) mineralization is essential for predicting the climate warming-carbon cycle feedback. Here, we combined Tree-of-life sequencing (TOLseq; cross-domain profiling using ribosomal RNA) with quantitative conversion factors linking rRNA transcript abundance to biomass, to understand how soil food web changes affect SOC mineralization in an in situ soil warming experiment. Field observations showed that warming reduced SOC stocks, but after decades of warming SOC mineralization had acclimated. An energetic soil food web model revealed both bottom-up and top-down controls in the trophic cascades, shifting C flows from fungal and plant-associated channels towards the bacterial channel. This caused an increase in SOC mineralization rate in warmed soils of 30% per-unit biomass across the year.

microbiology↗

bioRxiv2026

Nuclear blebs are composed of variable chromatin states but consistently enrich transcription initiation relative to elongation

Nuclear blebs are herniations of the nucleus that occur in many human conditions including aging, heart disease, muscular dystrophy, and many cancers. Nuclear blebbing causes nuclear rupture and cellular dysfunction. However, understanding the formation, stability, and identification of nuclear blebs remains an ongoing challenge. Our previous studies reveal that nuclear blebs are best hallmarked by decreased DNA density. To determine if chromatin decompaction underlies decreased DNA density in nuclear blebs, we investigated the histone composition of nuclear blebs across multiple cell lines. Time lapse and immunofluorescence imaging revealed that global histone H2B and H3 levels are decreased in the nuclear bleb relative to the nuclear body. Next, we imaged histone modification states of euchromatin and heterochromatin, which respectively track decompact and compact states of chromatin. Overall, we find that nuclear blebs display variable histone modification state across cell lines, as euchromatin does not consistently enrich nor is heterochromatin consistently depleted. Nuclear blebs did consistently show active RNA Pol II initiation is enriched relative to elongation. Thus, we find that the local histone modification state is not an essential component of nuclear blebs while transcription initiation enrichment over elongation is reproducible across cell lines and conditions. Summary statementWe measured histones and their modification states in nuclear blebs. We find that chromatin state is variable while transcription initiation is consistently enriched relative to elongation in nuclear blebs.

cell biology↗

bioRxiv2026

Age-related Delays in Osteochondral Remodeling of Fracture Healing Illustrated by Mass Spectrometry Imaging

Age-related delays in fracture healing are prevalent and contribute to morbidity and mortality in elderly populations. Clinical and preclinical studies demonstrate that aging is associated with slower and less complete fracture repair characterized by delayed cartilage and bone formation, impaired matrix resorption, and an increased risk of delayed union or non-union. Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry Imaging (MALDI MSI) enables spatially resolved, in situ molecular analysis of proteins directly from murine fracture tissues. We applied collagenase type III (MMP-13) mediated proteolytic digestion to formalin-fixed, paraffin-embedded (FFPE) tibia fracture callus sections harvested 10 days post-tibial fracture from young (3-month-old) and aged (18-month-old) mice to perform spatially resolved proteomic profiling. Spatial MS Imaging revealed pronounced age-dependent differences in extracellular matrix protein composition and remodeling within the fracture callus. We identified upregulation of canonical bone and matrix proteins, including Col1a1 and Col1a2 specifically in the young fracture callus demonstrating advancement into harden callus formation. Conversely, Col2a1 and other soft callus proteins were only seen in the aged callus tissues. Further, protein indicators of tissue state, such as fibronectin (upregulated) and calreticulin (downregulated) were selectively regulated aged tissues, demonstrating a failure for aged tissues to fully progress into harden calluses. Spatial proteomic patterns demonstrated a marked delay in progression from cartilaginous to osseous callus in aged mice, consistent with impaired matrix remodeling during fracture repair. Together, these findings establish spatial MS Imaging based proteomics as a powerful approach to elucidate age-related alterations in fracture healing and to identify molecular regulators of impaired skeletal regeneration. Lay SummaryUsing spatially-resolved proteomics via mass spectrometry imaging on fracture callus tissues from young and aged mice, we observed delayed healing in aged animals based on the composition of the extracellular matrices. Higher levels of bone specific collagens were detected in young animals, whereas cartilage specific collagens were detected in aged animals at higher levels. Further, detection of novel, non-canonical callus proteins revealed critical transitional steps that are delayed in aged-callus tissues, and these may also contribute to the delayed healing aged animals.

biochemistry↗

bioRxiv2026

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↗

bioRxiv2026

CD81 is an Ebola virus inhibiting factor that is antagonized by GP and VP40

Viruses manipulate the host cell membrane of infected cells for evasion of antiviral immunity, prevention of superinfection and optimization of viral replication and spread. The Ebola virus glycoprotein (EBOV GP) mediates virus entry, but is also known as important factor for subversion of the hosts antiviral immune response. We characterized the dysregulation of cell surface-residing proteins by EBOV GP and found that among several membrane proteins GP interferes with the tetraspanins CD81, CD63 and CD9. This was a conserved function of several filoviral GPs and not observable for viral glycoproteins of other virus families. While CD63 and CD9 were largely dispensable for EBOV replication, CD81 suppressed virus-like particle entry and replication at multiple steps. This phenotype might be explainable by sustained suppression of NF{kappa}B by CD81, that is otherwise activated by VP40 and EBOV trVLP replication. We further demonstrate that not only GP but also VP40 interferes with CD81 functionality and that antibody-mediated clustering of CD81 suppresses EBOV infection. Altogether, the tetraspanin CD81 emerges as druggable NF{kappa}B and EBOV-inhibiting factor, supporting an important role of NF{kappa}B in EBOV replication and potentially virus-induced immunopathogenesis. HighlightsO_LIEBOV GP and VP40 interfere with CD81 cell surface expression C_LIO_LICD81 suppresses NF{kappa}B signaling which is activated by VP40 C_LIO_LICD81 restricts EBOV VLP uptake and replication C_LIO_LITargeting CD81 by a crosslinking antibody inhibits EBOV infection C_LI

microbiology↗

bioRxiv2025

Molecular maps of diseases from omics data and network embeddings

Identifying disease-relevant proteins and pathways remains a fundamental challenge in understanding disease mechanisms and supporting therapeutic development. While omics analyses can provide valuable insights, they typically consider each gene/protein separately rather than at the level of biological systems. This can be addressed by combining the omics data with protein networks. We integrate disease-specific omics data with a universal functional association network from STRING, which we represent using node2vec embedding. This way, we constructed disease maps for seven diseases spanning inflammatory, oncological, neurological, and vascular diseases based on genetics, transcriptomics, somatic mutation, and proteomics data. Compared to omics analysis alone, the use of a simple linear model on top of network embedding enabled us to identify 2-4 times as many known disease-relevant proteins at the same specificity. Clustering of the resulting disease maps revealed both functional modules shared by many diseases, such as inflammatory pathways and cancer hallmarks, and disease-specific modules, such as keratinization in atopic dermatitis and extracellular matrix remodeling in aortic aneurysm. Together, these results highlight the value of protein network embedding when analyzing omics data to understand diseases.

bioinformatics↗

bioRxiv2025

Deficiency of Mesencephalic Astrocyte-derived Neurotrophic Factor Aggravates Acute Pancreatitis in Mice

Acute pancreatitis (AP) is a complex and potentially severe inflammatory disorder of the pancreas and is one of the most common causes of gastrointestinal hospitalization. Although environmental risk factors such as alcohol and gallstones are well recognized, only a subset of exposed individuals develop AP, suggesting that intrinsic factors, including genetic susceptibility, influence disease onset and progression. Endoplasmic reticulum (ER) stress has emerged as a key mechanism in AP pathogenesis, because ER is essential for protein synthesis, folding, degradation and secretion (proteostasis). Mesencephalic astrocyte-derived neurotrophic factor (MANF), an ER stress-inducible protein highly expressed in the pancreas, plays a critical role in maintaining proteostasis, yet its involvement in AP remains unclear. To investigate the functional role of MANF in AP, we generated pancreas-specific MANF knockout (MANF-KO) mice using the Cre/loxP system and subjected them to moderate experimental AP, that is caerulein- or alcohol-induced AP in mice. In the caerulein model, MANF deficiency exacerbated pancreatic injury in both sexes, as indicated by increased apoptosis (cleaved caspase-3, caspase-12), ER stress markers (eIF2, p-eIF2, GRP78), inflammation (IL-6, TNF), regenerative activity (Ki67), and pancreatic lipase levels. Notably, male MANF-KO mice exhibited enhanced inflammation (HMGB1), macrophage infiltration (CD68), and oxidative stress (DNP, HNE), which were not observed in females. In the alcoholic AP model, both male and female MANF-KO mice showed increased ER stress (p-IRE1, p-eIF2, GRP78), apoptosis, inflammation, macrophage infiltration, regeneration, and lipase levels, whereas elevated HMGB1 expression and oxidative stress again predominantly occurred in male MANF-KO mice. Together, these findings reveal a critical and sex-specific role for MANF in regulating pancreatic stress responses and inflammatory injury, supporting its potential contribution as a genetic factor in AP pathogenesis.

pathology↗

bioRxiv2025

Age-Related Alterations in the Expression of Mesencephalic Astrocyte-derived Neurotrophic Factor in the Brain and Their Impact on Neurobehavioral Functions

Mesencephalic astrocyte-derived neurotrophic factor (MANF) is a neurotrophic protein localized in the endoplasmic reticulum (ER) and pivotally involved in maintaining ER homeostasis. MANF plays an important role in mitigating neurodegenerative processes. Aging, the primary risk factor for neurodegenerative diseases (NDDs), is associated with significant alterations in ER function. The ER, central to protein synthesis, folding, degradation and secretion (proteostasis), experiences considerable stress in NDDs, which activates the unfolded protein response (UPR). We hypothesized that MANF and UPR is crucial for maintaining proteostasis during aging, but their efficacy declines with age, therefore increasing vulnerability to NDDs. We measured MANF levels in the brain and plasma of 1-, 4-, 11-, and 22-month-old male and female mice. A progressive decline of MANF levels was observed, with the lowest levels detected in 22 months. Reduced MANF expression was found in aged mice across several brain areas, including the cerebral cortex, olfactory bulb, thalamus, hypothalamus, hippocampus, and cerebellum. There was a sex difference in MANF levels in aged mice. Aging also altered the expression of UPR and MANF interacting proteins. Using cerebellar Purkinje cell (PC)-specific MANF deficient mice, we showed that MANF deficiency impaired motor coordination in female, but not male mice. MANF deficiency weakened spatial learning and memory in both male and female mice. Male MANF deficient mice displayed increased sociability, whereas female mice exhibit social withdrawal. Taken together, MANF expression in the brain declined with age and MANF deficiency impacted neurobehaviors in the aging animal in a sex-specific manner.

neuroscience↗