Biology subjects

Yu, L.

Publications and source records attributed to Yu, L..

At least 91 records · Page 5Linked to original sources

bioRxiv2025

Antigenic and Virological Characteristics of SARS-CoV-2 Variant BA.3.2, XFG, and NB.1.8.1

The emergence of the SARS-CoV-2 saltation variant BA.3.2, which harbors over 50 mutations relative to its ancestral BA.3 lineage, has raised concerns about its potential to drive outbreaks similar to BA.2.86/JN.1. Concurrently, variants such as NB.1.8.1, LF.7.9, XEC.25.1, XFH, and XFG exhibit enhanced growth advantages over LP.8.1.1, necessitating a comparative analysis of their antigenic and virological characteristics. Here, we evaluated the infectivity, ACE2-binding efficiency, and immune evasion of these variants. Pseudovirus assays revealed BA.3.2s robust antibody evasion, including resistance to Class 1/4 monoclonal antibodies; however, its ACE2 engagement efficiency was markedly reduced due to a closed spike conformation, leading to low infectivity. While XFG and LF.7.9 demonstrated strong immune escape associated with A475V and N487D mutations, their reduced receptor-binding efficiency suggested a need for compensatory adaptations. In contrast, NB.1.8.1 retained high ACE2 affinity and humoral immune evasion, supporting its potential for future dominance. Collectively, BA.3.2s current profile limits its ability to compete with emerging variants like NB.1.8.1. Sustained monitoring of BA.3.2s evolution-- particularly for mutations stabilizing an open RBD conformation or enhancing escape from Class 1 antibodies--is essential to assess its outbreak potential.

immunology↗

bioRxiv2025

K48-ubiquitin-activated proteases cut-up post-ER proteins

Polyubiquitin chains, linked via K48 or K63 of ubiquitin, target membrane proteins in the secretory system to degradative pathways. However its unclear whether these linkage isomers are functionally interchangeable. Here we show that for post-endoplasmic reticulum (ER) proteins, K63-linked polyubiquitination induces multivesicular bodies (MVBs) sorting and lysosomal degradation. In contrast, K48-linked polyubiquitination induces shearing from the membrane. Substrates are cleaved by the proteasome and by two ubiquitin-activated proteases: Ddi1, a conserved cytosolic ubiquilin that generates cytosolic fragments, and Rbd2, an intramembrane rhomboid protease that produces lumenal fragments. Rbd2 localizes to Golgi/endosomes but also acts on ubiquitinated substrates at the vacuolar membrane. Ddi1s catalytic core, the HDD-RVP domain is sufficient for ubiquitin-dependent proteolysis. It binds ubiquitin directly and its activity is amplified by auxiliary ubiquitin binding domains: an atypical UBL domain and a UBA domain. These findings demonstrate that polyubiquitin chains linked by different residues encode distinct degradative fates for post-ER proteins, and reveals two proteases that target ubiquitinated integral membrane cargo.

cell biology↗

bioRxiv2025

Translating the Post-Mortem Brain Multi-Omics Molecular Taxonomy of Alzheimer's Dementia to Living Humans

Alzheimers disease (AD) dementia is characterized by significant molecular and phenotypic heterogeneity, which confounds its mechanistic understanding, diagnosis, and effective treatment. In this study, we harness the most comprehensive dataset of paired ante-mortem blood omics, clinical, psychological, and post-mortem brain multi-omics data and neuroimaging to extensively characterize and translate the molecular taxonomy of AD dementia to living individuals. First, utilizing a comprehensive integration of eight complementary molecular layers from brain multi-omics data (N = 1,189), we identified three distinct molecular AD dementia subtypes exhibiting strong associations with cognitive decline, sex, psychological traits, brain morphology, and characterized by specific cellular and molecular drivers involving immune, vascular, and oligodendrocyte precursor cells. Next, in a significant translational effort, we developed predictive models to convert these advanced brain-derived molecular profiles (AD dementia pseudotimes and subtypes) into blood-, MRI- and psychological traits-based markers. The translation results underscore both the promise of these models and the opportunities for further enhancement. Our findings enhance the understanding of AD heterogeneity, underscore the value of multi-scale molecular approaches for elucidating causal mechanisms, and lay the groundwork for the development of novel therapies in living persons that target multi-level brain molecular subtypes of AD dementia.

neuroscience↗

bioRxiv2025

Altered Interpersonal Neural Synchronization during Social Interaction After Shared Excluded Experiences in Depressed Adolescents

BackgroundMajor depressive disorder (MDD) is common in adolescents, and the special development stage, during which adolescents brain and neuroendocrine system develop intensively, makes it subtly difficult to develop prevention and treatment strategies for depressed adolescents compared with depressed adults. Meanwhile, public psychosocial stressors significantly influence adolescents mental health and social interaction, rendering it essential to explore how a shared psychosocial stressor, i.e., shared excluded experiences, influences social interaction in depressed adolescents. MethodsWe designed a 4-player cyberball game to probe adolescents responses to shared excluded experiences and explore the underlying interpersonal neural synchronization (INS) with functional near-infrared spectroscopy (fNIRS). ResultsWe found that shared excluded experiences could enhance adolescents social interaction preferences but decreased INS in each pair of excluded adolescents, which indicates a reduced willingness to interact with others after the exclusion. However, no significantly different behavioral responses to the shared excluded experiences were found in depressed adolescents compared to adolescents as healthy controls (HC). Further analyses revealed that adolescents with MDD experienced more negative feelings than HC after exclusion. Of note, adolescents with MDD demonstrated stronger INS than HC, indicating the potential empathic stress in depressed adolescents. In addition, there existed altered brain-behavioral association patterns in responses to shared excluded experiences in depressed adolescents. ConclusionsIn summary, our study gives us deeper insights into how a shared psychosocial stressor impacts the INS in depressed adolescents, and it might be demonstrated that INS could be more sensitive than behavioral responses to detect social interaction deficits in depressed adolescents.

neuroscience↗

bioRxiv2025

SRSF3 is oncogenic in breast but tumor-suppressive in liver by differential regulation of gene expression

SRSF3 (SRp20) is an essential splicing factor. We discovered Srsf3 plays an oncogenic role in breast cancer and Srsf3 knockout (KO) in mammary glands delays the development of breast cancer in an Erbb2 mouse model. In contrast, Srsf3 is tumor-suppressive in mouse liver tissues. Srsf3 KO in hepatocytes enhances DEN-induced liver cancer and disrupts the sex disparity in DEN-induced liver cancer. Comparing to Srsf3 WT liver cancer, Srsf3 KO significantly increases Sox4, E2f1, Trpv4, Trim6, and Myc expression, but does not so in Erbb2 breast cancer. Srsf3 KO inhibits expression of Mfsd4a and Eif4a2 in breast cancer but enhances Mfsd4a and Eif4a2 expression in liver cancer. Moreover, Srsf3 KO suppresses the expression of ER and Foxa genes to reduce Lifr and Egfr but induce Myc expression and promote liver cancer in female mice. Together, our data highlight a new functional paradigm of SRSF3 at its physiological level in tissue context-dependent gene regulation.

cancer biology↗

bioRxiv2025

Multi-omic subtypes of Alzheimer's dementia are differentially associated with psychological traits

ImportancePsychological traits reflecting neuroticism, depressive symptoms, loneliness, and purpose in life are risk factors of AD dementia; however, the underlying biologic mechanisms of these associations remain largely unknown. ObjectiveTo examine whether one or more multi-omic brain molecular subtypes of AD is associated with neuroticism, depressive symptoms, loneliness, and/or purpose in life. DesignTwo cohort-based studies; Religious Orders Study (ROS) and Rush Memory and Aging Project (MAP), both ongoing longitudinal clinical pathological studies that began enrollment in 1994 and 1997. SettingOlder priests, nuns, and brothers from across the U.S. (ROS) and older adults from across the greater Chicago metropolitan area (MAP). Participants822 decedents with multi-omic data from the dorsolateral prefrontal cortex. Exposure(s)Pseudotime, representing molecular distance from no cognitive impairment (NCI) to AD dementia, and three multi-omic brain molecular subtypes of AD dementia representing 3 omic pathways from no cognitive impairment (NCI) to AD dementia that differ by their omic constituents. Main outcome(s) and measure(s)We first ran four separate linear regressions with neuroticism, depressive symptoms, loneliness, purpose in life as the outcomes, and pseudotime as the predictor, adjusting for age, sex and education. We then ran four separate analyses of covariance (ANCOVAs) with Bonferroni-corrected post-hoc tests to test whether the three multi-omic AD subtypes are differentially associated with the four traits, adjusting for the same covariates. ResultPseudotime was positively associated (p<0.05) with neuroticism and loneliness. AD subtypes were differentially associated with the traits: AD subtypes 1 and 3 were associated with neuroticism; AD subtype 2 with depressive symptoms; AD subtype 3 with loneliness, and AD subtype 2 with purpose in life. Conclusions and RelevanceThree multi-omic brain molecular subtypes of AD dementia differentially share omic features with four psychological risk factors of AD dementia. Our data provide novel insights into the biology underlying well-established associations between psychological traits and AD dementia. Key pointsO_ST_ABSQuestionC_ST_ABSAre three distinct multi-omic brain molecular subtypes of Alzheimers disease (AD) dementia associated with four well-established psychological AD risk factors (neuroticism, depressive symptoms, loneliness and purpose in life)? FindingsWe found differential associations: AD subtypes 1 and 3 were associated with neuroticism, AD subtype 2 was associated with depressive symptoms, AD subtype 3 was associated with loneliness; and AD subtype 2 was associated with purpose in life. MeaningPsychological risk factors might be associated with AD dementia via shared multi-omic molecular pathways.

molecular biology↗

bioRxiv2025

An Nlrp5-null mutation leads to attenuated de novo methylation in oocytes, accompanied by a significant reduction in DNMT3L

Nlrp5 encodes a core component of the subcortical maternal complex (SCMC) a cytoplasmic protein structure unique to the mammalian oocyte and cleavage-stage embryo. NLRP5 mutations have been identified in patients presenting with early embryo arrest, recurrent molar pregnancies and imprinting disorders. Correct patterning of DNA methylation over imprinted domains during oogenesis is necessary for faithful imprinting of genes. It was previously shown that oocytes with mutation in the human SCMC gene KHDC3L had globally impaired methylation, indicating that integrity of the SCMC is essential for correct establishment of DNA methylation at imprinted regions. Here, we present a multi-omic analysis of an Nlrp5- null mouse model, which in GV oocytes displays a misregulation of a broad range of maternal proteins, including proteins involved in several key developmental processes. This misregulation likely underlies impaired oocyte developmental competence. Amongst impacted proteins are several epigenetic modifiers, including a substantial reduction in DNMT3L; we show that de novo DNA methylation is attenuated in Nlrp5-null oocytes. This provides evidence for mechanisms leading to downstream misregulation of imprinted genes, which in turn, may result in imprinting syndromes, multi-locus imprinting disturbances (MLID) and hydatidiform moles.

developmental biology↗

bioRxiv2025

Non-invasive peripheral delivery of CDNF fragment protects neurons in models of Parkinsons and ALS

Non-invasive delivery of brain therapeutics is a key challenge for treating neurodegenerative diseases. Here, we discovered a novel carboxy (C)-terminal fragment of cerebral dopamine neurotrophic factor (C-CDNF) that protects dopamine (DA) and motoneurons (MNs) in rodent models of Parkinsons disease (PD) and amyotrophic lateral sclerosis (ALS). C-CDNF retains the same structure as CDNF and similarly to CDNF regulates cell stress pathways but unorthodoxly enters cultured neurons and passes through the blood-brain barrier. In vivo, intracranially or peripherally delivered C-CDNF improves motor deficits, protects DA neurons, and restores motor behavior in a rat model of PD. Subcutaneous C-CDNF also protects MNs and reduces microglial activation in an ALS model. Based on our findings, beginning C-CDNF treatment soon after diagnosis is anticipated to delay progression of PD and ALS, thereby improving treatment outcome. Thus, systemic delivery of C-CDNF should simplify the administration of protein-based therapeutics to patients while reducing treatment risk and financial burden for patients and families.

neuroscience↗

bioRxiv2025

CellFateExplorer: An integrated platform for exploring cell fate

Cell fate prediction from single-cell omics data is a central task for reconstructing developmental dynamics and inferring lineage relationships, but existing tools remain fragmented and often tailored to specific trajectory structures. Here we present Cafe (CelluAr Fate Explorer), an integrated platform for cell fate analysis that unifies trajectory-aware data storage, heterogeneous inference methods, benchmarking, visualization, and downstream interpretation. Cafe standardizes diverse inputs into a common milestone-network representation, supports both native and Dynverse-compatible methods, and evaluates performance across representative benchmark criteria. Applied to representative case studies across atlas-scale and lineage-resolved datasets, Cafe recovers coherent developmental trajectories and provides benchmark-guided method selection across data types and biological contexts. A browser-based interface built on cellxgene enables interactive trajectory inspection. Cafe also supports downstream analyses, including driver-gene prioritization and gene-regulatory-network inference. As an open, community-driven platform, Cafe is designed to evolve continuously with contributions from developers and users, expanding method coverage and functionality for cell fate prediction.

cell biology↗

bioRxiv2025

Benchmarking and optimizing Perturb-seq in differentiating human pluripotent stem cells

Perturb-seq is a powerful approach to systematically assess how genes and enhancers impact the molecular and cellular pathways of development and disease. However, technical challenges have limited its application in stem cell-based systems. Here, we benchmarked Perturb-seq across multiple CRISPRi modalities, on diverse genomic targets, in multiple human pluripotent stem cells, during directed differentiation to multiple lineages, and across multiple sgRNA delivery systems. To ensure cost-effective production of large-scale Perturb-seq datasets as part of the Impact of Genomic Variants on Function (IGVF) consortium, our optimized protocol dynamically assesses experiment quality across the weeks-long procedure. Our analysis of 1,996,260 sequenced cells across benchmarking datasets reveals shared regulatory networks linking disease-associated enhancers and genes with downstream targets during cardiomyocyte differentiation. This study establishes open tools and resources for interrogating genome function during stem cell differentiation.

genomics↗

bioRxiv2025

A field-focused systems approach reveals mRNA covalent modifications linked to sorghum growth and development under drought stress

RNA Covalent Modifications (RCMs) are post-transcriptional chemical alterations that influence RNA stability and translation efficiency, thus play critical roles in eukaryotic growth and development. However, their role in regulating plant performance under abiotic stress remain largely unexplored. Here, we integrated multi-omics data in six Sorghum bicolor accessions under water-limiting conditions in the field to explore the relationship between RCMs and drought response. Within a stress and photosynthesis-associated gene co-expression module, we identified SbDUS2, a member of family of enzymes, conserved across eukaryotes, which catalyzes the reduction of uracil to dihydrouridine (DHU) on RNA molecules. DHU-modified transcripts in this module were enriched for photosynthetic functions and showed strong correlation with photosynthetic traits. To elucidate the function of this RCM, we characterized loss of function dus2 mutants in the genetic model, Arabidopsis thaliana. Under control conditions, these DHU-deficient mutants exhibited impaired germination and delayed development. Furthermore, when exposed to heat or water-limiting conditions, these mutants showed significantly reduced net CO2 assimilation and survival. Using multiple transcriptome-wide RNA stability assays, we demonstrated that transcripts associated with lower DHU level in a dus2 background generally exhibited increased stability compared to Col-0 controls. Particularly, lack of DUS2 led to the hyperstability of photosynthesis-related transcripts, impeding their turnover and likely preventing proper photosynthetic acclimation during stress. We propose a model based on these data where DHU acts as a critical post-transcriptional regulator marking mRNAs for rapid turnover under stress, highlighting an overlooked regulatory layer contributing to plant resilience.

plant biology↗

bioRxiv2025

Hepatic fructose metabolism is antagonized by growth hormone/insulin-like growth factor signaling via regulation of ketohexokinase expression

Overconsumption of added sugars such as fructose has been associated with a remarkable decline in metabolic health. Fructose is primarily metabolized by the small intestines and the liver, via phosphorylation mediated by ketohexokinase (KHK). KHK activity is traditionally viewed as lacking negative feedback mechanisms, such as those present to limit glucose metabolism, leading to excessive fat accumulation characteristic of metabolic dysfunction-associated liver disease (MASLD). In this study, we observe KHK downregulation in hepatocytes of diet-induced and genetic models of MASLD. Reduced KHK coincides with decreased flux of fructose-derived carbons into glycolytic and amino acid metabolic pathways, suggesting the presence of mechanisms that limit KHK-mediated fructolysis in the liver. We subsequently focused on the growth hormone (GH)/insulin-like growth factor (IGF) signaling pathway as a potential mechanism antagonizing KHK expression. In transgenic mice with enhanced GH signaling, KHK levels are reduced, whereas reduced GH activity leads to increased KHK expression. Additionally, administration of GH and IGF-1 in liver cell cultures induces time-dependent degradation of KHK, facilitated by direct interactions between KHK and the IGF-1 receptor (IGF-1R). Single-nuclei RNA sequencing revealed elevated IGF-1R expression in hepatocytes from diet-induced MASLD mice, supported by human MASLD patient samples, which also show reduced KHK expression. Taken together, these findings describe a novel pathway by which GH/IGF-1 signaling regulates KHK, offering new insights into how the liver adapts to metabolic stress to limit fructose-driven liver dysfunction.

molecular biology↗

bioRxiv2024

Virological and antigenic characteristics of SARS-CoV-2 variants LF.7.2.1, NP.1, and LP.8.1

XEC and KP.3.1.1 have surpassed KP.3 to become the globally dominant lineages due to their unique NTD mutations. However, several emerging JN.1 sublineages, such as LF.7.2.1, MC.10.1, NP.1, and, especially, LP.8.1, have demonstrated superior growth advantages compared to XEC. It is critical to access the virological and antigenic characteristics of these emerging SARS-CoV-2 variants. Here, we found that LF.7.2.1 is significantly more immune invasive than XEC, primarily due to the A475V mutation, which enabled the evasion of Class 1 neutralizing antibodies. However, LF.7.2.1s weak ACE2 binding affinity substantially impaired its fitness. Likewise, MC.10.1 and NP.1 exhibited strong antibody immune evasion due to the A435S mutation, but their limited ACE2 engagement efficiency restricted their growth advantage, suggesting that A435S may regulate the Spike conformation, similar to the NTD glycosylation mutations found in KP.3.1.1 and XEC. Most importantly, we found that LP.8.1 showed comparable humoral immune evasion to XEC but demonstrated much increased ACE2 engagement efficiency, supporting its rapid growth. These findings highlight the trade-off between immune evasion and ACE2 engagement efficiency in SARS-CoV-2 evolution, and underscore the importance of monitoring LP.8.1 and its descend lineages.

immunology↗

bioRxiv2024

Integrated analysis of COVID-19 multi-omics data for eQTLs reveals genetic mechanisms underlying disease severity

The global pandemic caused by the SARS-CoV-2 virus provided an unprecedented opportunity to investigate genetic factors influencing the disease severity of the viral infection. Despite a plethora of recent research on both SARS-CoV-2 and COVID-19, few have taken a systems biology approach to address individual-level variation, especially based on non-European populations. Accordingly, we analyzed multi-omics data generated at three timepoints from 193 Korean COVID-19 patients with mild or severe symptoms, composed of whole genome sequencing, blood-based single-cell RNA-sequencing (2.15M cells), 195 cytokine profiles, and human leukocyte antigen (HLA) allele data. We identified expression quantitative trait loci (eQTLs), disease severity interacting eQTLs (n = 388), and disease progression interacting eQTLs (n = 945) for various cell types. We elucidated a complex regulatory mechanism involving HLA genes and their targets, and identified genetic determinants of cytokine levels. Finally, we show how regulation of ieQTLs is established by upstream transcription factors (TFs), illustrating complex regulation of the IGFBP7 ieQTL by a combined action of two TFs, which is potentially important in conferring differential severity. This study illuminates an efficient molecular interrogation framework that can be applied toward understanding infectious disease progression in individuals of different genotypes.

genetics↗

bioRxiv2024

Molecular Insights into the Regulation of GNPTAB by TMEM251

In vertebrates, newly synthesized lysosomal enzymes traffick to lysosomes through the mannose-6-phosphate (M6P) pathway. The Golgi membrane protein TMEM251 was recently discovered to regulate lysosome biogenesis by controlling the level of GlcNAc-1-phosphotransferase (GNPT). However, its precise function remained unclear. In this study, we demonstrate that TMEM251 is a two-transmembrane protein indispensable for GNPT stability, cleavage by Site-1-Protease (S1P), and enzymatic activity. We reconcile conflicting models by showing that TMEM251 enhances GNPT cleavage and prevents its mislocalization to lysosomes for degradation. We further establish that TMEM251 achieves this by interacting with GOLPH3 and retromer complexes to anchor the TMEM251-GNPT complex at the Golgi. Alanine mutagenesis identified F4XXR7 motif in TMEM251s N-tail for GOLPH3 binding. Together, our findings uncover TMEM251s multi-faceted role in stabilizing GNPT, retaining it at the Golgi, and ensuring the fidelity of the M6P pathway, thereby providing insights into its molecular function.

cell biology↗

bioRxiv2024

Sirt5 preserves cardiac function in ischemia-reperfusion injury by inhibiting ANT2 lactylation

Myocardial ischemia-reperfusion (IR) injury is the most common type of heart disease. IR-disrupted mitochondrial homeostasis affects heart energy metabolism and function, but the mechanism remains poorly understood. Here we report a cardioprotective role of the mitochondrial protein Sirt5 in a mouse model of cardiac IR injury. The down-regulation of Sirt5 in IR-injured heart is associated with an increased protein lactylation and impaired mitochondrial function. Overexpression of Sirt5 alleviates, whereas conditional knockout of Sirt5 aggravates, mitochondrial damage and cardiac injury. Mechanistically, Sirt5 interacts with the inner mitochondrial membrane protein adenine nucleotide translocase 2 (ANT2), inhibiting its lysine lactylation to promote its association with the outer mitochondrial membrane protein voltage-dependent anion-selective channel 1 (VDAC1). Lactylation-resistant ANT2 efficiently complexes with VDAC1 and improves cardiac function after injury. Therefore, we uncover a Sirt5-regulated interaction of ANT2 and VDAC1 in maintaining mitochondrial homeostasis, highlighting the potential of targeting ANT2 lactylation as a therapeutic strategy in the treatment of cardiac injury. TeaserSirt5 promotes the interaction of mitochondrial proteins to protect mitochondrial homeostasis and improve heart function in ischemia-reperfusion injury.

pathology↗

bioRxiv2024

CLUEY enables knowledge-guided clustering and cell type detection from single-cell omics data

Clustering is a fundamental task in single-cell omics data analysis and can significantly impact downstream analyses and biological interpretations. The standard approach involves grouping cells based on their gene expression profiles, followed by annotating each cluster to a cell type using marker genes. However, the number of cell types detected by different clustering methods can vary substantially due to several factors, including the dimension reduction method used and the choice of parameters of the chosen clustering algorithm. These discrepancies can lead to subjective interpretations in downstream analyses, particularly in manual cell type annotation. To address these challenges, we propose CLUEY, a knowledge-guided framework for cell type detection and clustering of single-cell omics data. CLUEY integrates prior biological knowledge into the clustering process, providing guidance on the optimal number of clusters and enhancing the interpretability of results. We apply CLUEY to both unimodal (e.g. scRNA-seq, scATAC-seq) and multimodal datasets (e.g. CITE-seq, SHARE-seq) and demonstrate its effectiveness in providing biologically meaningful clustering outcomes. These results highlight CLUEY on providing the much-needed guidance in clustering analyses of single-cell omics data. CLUEY package is available from https://github.com/SydneyBioX/CLUEY.

bioinformatics↗

bioRxiv2024

Accurate prediction of CRISPR editing outcomes in somatic cell lines and zygote with few-shot learning

The CRISPR-Cas system has revolutionized gene editing, while its outcome prediction remains unsatisfactory, especially in new cell states due to their distinct DNA repair preferences. In this study, we introduce inDecay, a flexible system for predicting CRISPR editing outcomes from target sequence, returning probabilities of nearly the full spectrum of indel events. Uniquely, inDecay utilizes informative and parameter-efficient features for each indel event and incorporates cell-type-specific repair preferences through a multi-stage design. While both inDecay and existing methods achieve accurate results for prediction within cell lines, only inDecay with transfer learning can retain the high performance for cross-cell line prediction. We then applied inDecay to mouse embryo editing using our newly generated data and observed remarkable accuracy by including as few as 30 fine-tuning embryonic samples. Notably, inDecay is the first software to predict embryonic editing. Therefore, our few-shot learning-supported system may accelerate guide RNA prioritization in mouse model generation, mammal embryonic gene editing, and cellular therapeutics.

bioinformatics↗