bioRxiv Science⌕ Search

Biology subjects

Zheng, R.

Publications and source records attributed to Zheng, R..

At least 37 records · Page 2Linked to original sources

Sequence-aware Prediction of Point Mutation-induced Effects on Protein-Protein Binding Affinity using Deep Learning

Amino acid mutations may lead to significant changes in the binding affinity of protein complexes, thereby causing a series of cellular dysfunctions. Therefore, accurate prediction of protein-protein binding affinity changes ({Delta}{Delta}G) induced by amino acid mutations is of great importance for understanding protein-protein interactions (PPIs). In this study, we propose SAMAffinity, a protein sequence-aware deep learning architecture for predicting changes in protein-protein binding affinity caused by amino acid mutations. SAMAffinity predicts mutation-induced {Delta}{Delta}G by integrating multi-source sequence features, leveraging a Mutation-Site Identification (MSI) module to highlight local semantic shifts and a Binding-Interface Awareness (BIA) module to capture interaction changes. Benchmark evaluations on public datasets show that under the mutation-level data splitting strategy, SAMAffinity outperforms the state-of-the-art sequence-based method AttABseq by 33.3%, 72.3%, 31.8%, and 30.5% on S1131, S4169, S645, and M1101 datasets, respectively. Moreover, under the complex-level data splitting strategy, SAMAffinity surpasses the structure-based method MpbPPI by 22.9%, 22.7%, 5.0%, and 11.4% on the corresponding datasets. Beyond predictive accuracy, the strong consistency between the models predicted distribution and natural amino-acid mutation tendencies indicates that SAMAffinity effectively captures the underlying mutational landscape shaped by intrinsic biochemical and evolutionary factors. Based on this capability, SAMAffinity demonstrated strong generalization in a study of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cases, suggesting its potential for optimizing therapeutic antibody design.

bioinformatics↗

Mineral guided molecular enrichment: An interfacial driving force for protocell emergence on early Earth

The emergence of protocells from a dilute prebiotic environment is a fundamental challenge in origins-of-life research. which requires the simultaneous overcoming of molecular dilution, the establishment of metabolic cycles and the formation of selectively permeable compartments. But where and how such critical conditions are satisfied is very obscure and debated. We demonstrate, using contemporary model proteins and enzymatic systems, that mineral surfaces can facilitate the co-adsorption and spatial arrangement of nucleotides, proteins, and lipids into locally enriched, protocell-like assemblies under the examined laboratory conditions. We showed that geochemically relevant minerals efficiently co-adsorb and colocalize diverse biomolecules, creating crowded interfacial microenvironments that support enzyme cascades with substrate channeling-like behavior. Subsequently, these mineral-protein complexes template the assembly of lipid membranes, leading to the formation of discrete compartments that maintain metabolic activity while permitting molecular exchange. This mineral-guided surface enrichment (MSE) mechanism integrates key aspects of "metabolism-first" and "membrane-first" scenarios into a unified pathway, reconciling long-standing conceptual divides in prebiotic chemistry. Our findings establish mineral interfaces as active organizers of protocell emergence, offering a geochemically plausible framework for the origin of cellular life.

evolutionary biology↗

A BCG toxic effector induces mitochondrial DNA compaction to refrain protective immunity

Innate immune memory typically emphasizes nuclear chromatin remodeling that determines transcriptional memory in monocytes and macrophages. Here, we show that compaction of mitochondrial DNA (mtDNA), governed by mitochondrial transcription factor A (TFAM) abundance and mtATP-dependent remodeling, defines the transcriptional and functional state of trained macrophages. While typical pathogen-associated molecular pattern (PAMPs) triggered mtDNA accessibility, Bacillus Calmette-Guerin (BCG) effector PE18 directly interacted with and activated SLC25A5 to reduce mtATP levels, thereby inhibiting TFAM degradation by AFG3L2. Accumulated TFAM restricts mtDNA accessibility, suppressing the transcription of the mtNd1 and thereby reducing mtNd1-mediated mtROS production, which diminishes the trained capacity of macrophages against secondary infections. Notably, BCG{Delta}pe18 maintains macrophages cytokine transcriptional capacity independent of classical nuclear histone modifications. Moreover, BCG{Delta}pe18 provides robust and lifelong protective immunity against Mycobacterium tuberculosis (Mtb) infection. These findings reveal mitochondrial genome as a regulatory entity in trained immunity, and suggest a potential strategy for improving vaccine performance.

immunology↗

Dosage-sensitive RBFOX2 autoregulation promotes cardiomyocyte differentiation through transcriptome maturation

Haploinsufficiency of the RNA splicing regulator, RBFOX2, is linked to congenital heart disease (CHD), yet its pathogenic mechanisms remain unclear. Here, we demonstrate that RBFOX2 is essential for progressing cardiomyocyte (CM) differentiation by shifting exon usage profiles to more mature patterns in sarcomere, cytoskeletal, and focal adhesion genes, including alpha-actinin-2 (ACTN2). This maturation program is initiated by critical levels of RBFOX2 that facilitate autoregulatory splicing at mutually exclusive exons encoding early and late isoforms with distinct functional roles. In heterozygous CMs, autoregulation is disrupted, which skews isoform ratios and generates a dominant-negative product caused by exon co-inclusion. Finally, we demonstrate that overexpression of ACTN2 rescues heterozygous, but not null, phenotypes by restoring contractility, which triggers a mechanosensing feedback loop involving upregulation of RBFOX2 from the wildtype allele and transcriptome maturation. Our data suggest that decreased RBFOX2 dosage and autoregulation impair CM differentiation, contributing to CHD pathogenesis and heart failure susceptibility.

developmental biology↗

The effects of increasing renal perfusion pressure on renal hemodynamics, microcirculation,and oxygen metabolism in a septic shock model

BackgroundThe optimal target for mean arterial pressure (MAP) during clinical management of septic shock remains a topic of debate. This study investigates how elevating MAP, and thereby increasing renal perfusion pressure (RPP, defined as MAP-CVP), influences renal hemodynamics, microcirculation, and oxygen metabolism in a septic shock model. MethodsSixteen New Zealand rabbits of either sex and similar weight were randomly assigned to sham group (n=8) and septic shock group (n=8). Renal blood flow (RBF), microcirculatory blood flow and velocity in the kidney, as well as tissue oxygen pressure in the renal cortex and medulla, were assessed at four distinct time points: baseline (T0), model establishment (T1), restoration of MAP to baseline levels (T2), and an increase in MAP by more than 15% above baseline (T3). ResultsWithin the septic shock group, although MAP and consequent RPP were increased, RBF markedly decreased from 17.63{+/-}2.50 to 8.50{+/-}1.93 ml/min (p < 0.05). No significant changes in microcirculation blood flow or flow velocity were observed between T2 and T3. Tissue oxygen pressure in the renal cortex and medulla declined significantly from 21.20{+/-}1.80 to 17.14{+/-}1.72 (p < 0.05) and from37.74{+/-}4.85 to 24.34{+/-}3.74 (p < 0.05), respectively. ConclusionElevating RPP does not improve RBF, renal microcirculation, or tissue oxygen pressure in the renal cortex or medulla in septic shock. Elevating RPP does not improve RBF, renal microcirculation, or tissue oxygen pressure in the renal cortex or medulla in septic shock. We advocate restoring MAP to the baseline level rather than increasing it further to enhance renal perfusion pressure.

systems biology↗

Human single-cell atlas analysis reveals heterogeneous endothelial signaling

Endothelial cells (ECs) play complex roles across tissues and vessel types. Yet, systematic investigations of EC heterogeneity in the combined context of vessel type and tissue microenvironment are still largely lacking. We integrated over three million single cells of scRNA-seq datasets in 15 human tissues and found that ECs in some tissues (e.g., heart and kidney) exhibited greater tissue specificity, while others displayed more substantial vessel specificity. We developed a computational pipeline to analyze cell-cell communications (CCC) mediated by metabolites or proteins to explore microenvironmental regulation. Interestingly, our results showed that CCC events involving ECs varied vastly across tissues, highlighting tissue-specific EC interactions. Using topic modeling, we identified CCC patterns, termed CCC topics, representing metabolite- and protein-mediated interactions between ECs and other tissue-resident cells. Most CCC topics exhibited high tissue specificity, potentially explaining microenvironmental regulations for EC heterogeneity. The work systematically investigates EC heterogeneity and provides insights into how EC heterogeneity was regulated across diverse tissue microenvironments.

bioinformatics↗

A genetically engineered vertebrate animal model of NAA15-related heart disease uncovers myocardial growth, contractility, and mitochondrial defects

Delineating the genetic and environmental instigators of congenital heart disease (CHD), affecting up to 1% of newborns, will improve preventative, diagnostic, and therapeutic efforts to mitigate disease outcomes. Although mutations in NAA15, which encodes the auxiliary subunit of N-alpha-acetyltransferase A (NatA), are associated with CHD in humans, vertebrate animal models of NAA15-related heart disease have yet to be described. Therefore, we isolated zebrafish strains carrying null mutations in paralogs naa15a and naa15b, which we co-localized to the early larval myocardium. Double knockout (DKO) naa15-deficient larvae exhibited diminutive, lowly contractile, and bradycardic ventricles composed of fewer and smaller cardiomyocytes (CMs) incapable of proliferation. On a subcellular level, mutant CMs exhibited moderately disorganized myofibrils. CM-specific re-expression of naa15a partially rescued the contractility and growth deficits, revealing an indispensable myocardial function. Ubiquitous mis-expression of human NAA15 achieved complete rescue, enabling functional testing of human NAA15 variants. Animals with a reduced dosage (RD) of naa15 survived to adulthood and shared phenotypes with DKO larvae, including smaller ventricular chambers and CMs, which exhibited mosaic myofibril disarray. Deep quantitative proteomic profiling of WT and naa15RD adult hearts revealed differential expression of multiple protein classes, including several subunits of mitochondrial respiratory complex I, a component of the electron transport chain. Accordingly, we documented reduced mitochondrial content and function in the myocardium of naa15-deficient larvae. Taken together, our data reveal myocardial functional and structural abnormalities associated with mitochondrial dysfunction in a vertebrate animal model of NAA15-related heart disease.

developmental biology↗

Chromosomal-level genome of the Pinus massoniana 'Minlin WY36'

Owing to conifers complex and large genomes, it is challenging to construct a comprehensive reference genome and conduct evolutionary and genomic research. Here, we present the chromosome-level assembly of Pinus massoniana Minlin WY36, a pioneering conifer species used for afforestation, timber production, and oleoresin extraction. The genome size was determined to be 23.41 Gb, with a contig N50 value of 1.15 Mb and a scaffold N50 value of 2.02 Gb. A total of 23.16 Gb of reads (98.93% of the assembled genome) were anchored and oriented onto 12 pseudochromosomes, with chromosome lengths from 1.47 to 2.29 Gb. A total of 32,144 protein-coding genes were predicted, of which 27,173 (84.54%) were functionally annotated. The P. massoniana Minlin WY36 genome consists of 79.41% (18.57 Gb) repetitive sequences, among which long terminal repeat sequences (LTR) were the most abundant. Through comparative genomic analysis, we found that the unique and significantly expanded genes in P. massoniana Minlin WY36 were enriched in the metabolism related to resin synthesis. This study offers valuable insights into conifer evolution and contributes resources for further investigations of conifer adaptation and developmental processes.

genomics↗

Super-giga and tiny orchid genomes illuminate evolution of Orchidaceae

Orchidaceae (orchids) is commonly known as one of the largest families of seed plants, and grow in an extensive range of habitats worldwide. In the present study, we generated chromosome-level reference genomes for two orchids using a combination of PacBio, Illumina, and Hi-C sequencing, Cypripedium singchii has the largest genome and chromosomes among the sequenced species so far, with a genome size of 43.19 Gb (1C) with ten chromosomes, and Apostasia fujianica has the smallest known genome and chromosomes in Orchidaceae, with a genome size of 340.90 Mb (1C) with 35 chromosomes. We predicted a total of 32,412 and 21,724 protein-coding genes for C. singchii and A. fujianica, respectively. The overall BUSCO score was 85.01% for C. singchii and 91.80% in A. fujianica. Based on protein-coding sequences from 55 conserved single-copy families across 21 plant species, we constructed a high-confidence phylogenetic tree and estimated the divergence times. The high-quality genomes of super-giga and tiny orchids offer key insight for future evolutionary researches.

genomics↗

High-performance proteomics at any chromatographic flow rate

Current applications of mass spectrometry-based proteomics range from single cell to body fluid analysis that come with very different demands regarding sensitivity or sample throughput. Additionally, the vast molecular complexity of proteomes and the massive dynamic range of protein concentrations in these biological systems require very high-performance chromatographic separations in tandem with the high speed and sensitivity afforded by mass spectrometer. In this study, we focussed on the chromatographic angle and, more specifically, systematically evaluated proteome analysis performance across a wide range of chromatographic flow rates (0.3 - 50 L/min) and associated column diameters using a Vanquish Neo UHPLC coupled online to a Q Exactive HF-X mass spectrometer. Serial dilutions of HeLa cell line digests were used for benchmarking and total analysis time from injection-to-injection was intentionally fixed at 60 minutes (24 samples per day). The three key messages of the study are that i) all chromatographic flow rates are suitable for high-quality proteome analysis, ii) capLC (1.5 L/min) is a very robust, sensitive and quantitative alternative to nanoLC for many applications and iii) showcased proteome, phosphoproteome and drug proteome data provide sound empirical guidance for laboratories in selecting appropriate chromatographic flow rates and column diameters for their specific application.

systems biology↗

Cerebellin-2 positive (Cbln2+) Neurons in the Parafascicular Thalamic Nucleus Regulate Self-Grooming Behavior

Self-grooming represents a stereotyped repetitive behavior which is commonly observed in various neuropsychiatric disorders. Deep brain stimulation (DBS) targeting the centromedian / parafascicular complex (CM/PF) has been shown to alleviate obsessive-compulsive disorder/behavior (OCD/OCB) symptoms in human. However, little is known about the neural circuits of the PF that are involved in the regulation of self-grooming behavior in rodents. Here, we report that cerebellin-2 positive (Cbln2+) neurons in PF bidirectionally encode self-grooming. Chemogenetic activation of Cbln2+ PF neurons significantly reduces both physiological and pathological self-grooming, and chemogenetic inhibition of Cbln2+ PF neurons increases physiological self-grooming. Moreover, activating synaptic excitatory inputs to Cbln2+ PF neurons inhibits self-grooming, while synaptic inhibitory inputs enhance it. Cbln2+ PF neurons independently transmit neural signals to the dorsal and ventral striatum. Activation of PF-dorsal striatum and PF-ventral striatum pathways both inhibit self-grooming behavior. Most excitingly, we alleviate excessive grooming in OCD mice by the activation of PF neurons using non-invasive ultrasound stimulation. Together, these data reveal that Cbln2+ PF neurons are integral components of a brain network involved in self-grooming behavior and highly promising targets in the non-invasive therapy of OCD.

neuroscience↗

Characterization of deep-sea viruses reveals their unexpected diversity and roles in facilitating host metabolism of complex organic matter

Viruses exert a pervasive influence on biogeochemical cycles in deep-sea ecosystems. By integrating multi-omics and viral isolation data from four distinct deep-sea sediment sites, we uncover the diversity of DNA and RNA viral communities, which vary significantly across geographically separated cold seep and seamount environments. Host range predictions reveal both prokaryotic and eukaryotic communities are susceptible to viral infection. Metatranscriptomic analyses suggest viral functional genes are actively expressed, potentially enhancing host metabolism of complex organic matter (COM). Indeed, purified viruses from deep-sea sediments were shown to facilitate COM metabolism in certain deep-sea microorganisms, enabling the isolation of previously uncultured bacterial taxa. Notably, in these newly isolated bacteria, polysaccharides induced chronic virus release without cell lysis, a process that may assist host metabolism of polysaccharides. Our findings illuminate the diversity and roles of viral communities in distinct deep-sea sediments, underscoring their significant contribution to COM degradation and the deep-sea carbon cycle.

microbiology↗

Nicotinamide-loaded Peptoid Nanotubes for Energy Regeneration in Acute Brain Injury

Acute brain injuries such as perinatal asphyxia, stroke, and traumatic brain injury result in ischemia, oxidative stress, excitotoxicity, and inflammation, leading to a depletion of ATP, the brains cellular energy store. Nicotinamide adenine dinucleotide (NAD+), a key regulator of cellular homeostasis, is crucial for energy regeneration and DNA repair in post-injury recovery. However, the therapeutic benefits of NAD+ and its precursors, such as nicotinamide (NAM), are limited by the complexity of their metabolic pathways and challenges in effective cell-specific intracellular delivery. Therefore, cellular delivery strategies are needed to capture the potential of an NAD+-regenerating therapeutic approach. In this study, we introduce a nanopeptoid delivery strategy to replenish cellular redox state and energy production in the acutely injured brain. By self-assembling peptoids into tubular structures, we created biocompatible NAM-conjugated peptoid nanotubes (NAM-PNTs) that vary in tubular length. NAM-PNTs demonstrated significant therapeutic benefits by enhancing cell viability and replenishing intracellular ATP levels within 24 hours of treatment in oxygen-glucose deprived (OGD) BV-2 cells. In organotypic brain slices, NAM-PNT treatment promoted glial proliferation, reduced pro-inflammatory cytokine levels, and increased anti-inflammatory cytokines after OGD, an ex vivo model of hypoxia-ischemia. A single systemic dose of NAM-PNTs also reduced brain tissue loss and improved neuropathology after hypoxia-ischemia in term-equivalent rats. These findings highlight the strong therapeutic potential of NAM-PNTs for cell-specific targeted delivery and energy restoration in the acutely injured neonatal brain. In the neonatal brain injury field, this is the first demonstration of a novel nanoparticle platform development from first principles design and synthesis to in vitro screening and then demonstration of efficacy in vivo.

bioengineering↗

Nitrate-driven dark oxygen production by diverse deep-sea microorganisms

To date, only three biotic pathways for light-independent oxygen production (i.e., dark oxygen) have been reported: chlorate dismutation, nitric oxide dismutation, and methanobactin-dependent water lysis. Oxygen has been shown to be produced and consumed in dark and anoxic environments, as evidenced by its prevalence in deep-sea surface sediments. However, the microbial communities and pathways driving deep-sea dark oxygen production (DOP) remain poorly understood. Here we identify a novel DOP pathway driven by dissimilatory nitrate reduction to ammonium (DNRA) in two deep-sea Deferribacterota strains. The DOP activity of these Deferribacterota strains potentially promotes the formation of manganese nodules and influences the growth and metabolism of both aerobic and anaerobic microbes, underscoring the significant role of microbial DOP in shaping deep-sea geological and ecological systems. We also cultured several deep-sea DOP-capable microorganisms from the Campylobacterota, Deinococcota, and Pseudomonadota phyla, which generate dark oxygen through unidentified nitrate-driven pathways. Combined with previous geological evidence, our results suggest that nitrate-driven dark oxygen, alongside photosynthetic oxygen, jointly contributed to early Earths oxygenation, driving the Great Oxidation Event. Overall, our findings provide novel insights into deep-sea oxygen sources, shed light on the origins of early Earths oxygen, and expand perspectives on the potential for terraforming other planets.

microbiology↗

Spacer Extension Reconciles Specificity and Activity in High-Fidelity Cas9 Genome Editing

AbstractEngineering high-fidelity CRISPR enzymes often leads to reduced cleavage activity, creating a significant hurdle in balancing nuclease specificity and efficiency for clinical applications. Here, we demonstrate that extending the spacer to 21 or 22 nucleotides restores the impaired cleavage activity of SuperFi-Cas9, an engineered high-fidelity Cas9 variant with seven mutations at the PAM-distal region. Structural and mutational analyses reveal that the spacer extension strengthens additional interactions at the PAM-distal end, stabilizing the nuclease- sgRNA-DNA complex, which appears to be disturbed due to the seven mutations. This approach not only provides a high-fidelity Cas9 with uncompromised efficiency but also introduces a novel strategy to enhance CRISPR complex stability. Our findings offer a promising avenue for precise and efficient genome editing, crucial for advancing CRISPR technologies toward clinical translation.

genomics↗

ACE: a versatile contrastive learning framework for single-cell mosaic integration

The integration of single-cell multi-omics datasets is critical for deciphering cellular heterogeneities. Mosaic integration, the most general integration task, poses a greater challenge regarding disparity in modality abundance across datasets. Here, we present ACE, a mosaic integration framework that assembles two types of strategies to handle this problem: modality-alignment based strategy (ACE-align) and regression-based strategy (ACE-spec). ACE-align utilizes a novel contrastive learning objective for explicit modality alignment to uncover the shared latent representations behind modalities. ACE-spec combines the modality-alignment results and modality-specific representations to construct complete multi-omics representations for all datasets. Extensive experiments across various mosaic integration scenarios demonstrate the superiority of ACEs two strategies over existing methods. Application of ACE-spec to bi-modal and tri-modal integration scenarios showcases that ACE-spec is able to enhance the representation of cellular heterogeneities for datasets with incomplete modalities. The source code of ACE can be accessed at https://github.com/CSUBioGroup/ACE-main.

bioinformatics↗

OfWRKY33 binds to the key linalool synthase gene OfTPS7 to promote linalool synthesis in Osmanthus fragrans flowers

Volatile aroma compounds make significant contributions to human perception of flowers. Osmanthus fragrans is a famous aroma plant and linalool along with its oxides are proved to be the dominant aroma active compounds. Although some terpene synthases (TPSs) have been characterized, a comprehensive study of the hub metabolic gene and its transcriptional regulation remain to be revealed. Here, we selected a specific cultivar Boyeyingui (BBYG) with the highest content of linalool among 20 wide-cultivated cultivars for genome and transcriptome sequencings. Among the 25 new putative OfTPSs, only OfTPS6, OfTPS7 could exclusively produce linalool in planta. Biochemical analysis demonstrated that OfTPS6, OfTPS7 were able to catalyze geranyl diphosphate (GPP) into linalool and a small proportion of other monoterpenes in vitro. Spatial and temporal correlation analysis further confirmed the transcript level of OfTPS7 was closely associated with linalool content in diverse cultivars and different tissues, suggesting OfTPS7 was the essential linalool synthase gene. Combined with yeast one-hybrid screen and weighted correlation network analysis (WGCNA), a nucleus-localized transcriptional factor OfWRKY33 was considered as a potential modulator. Y1H, dual-luciferase assay and electrophoretic mobility shift assay (EMSA) demonstrated that OfWRKY33 directly bound to the W-box of OfTPS7 promoter to stimulate its transcription. OfWRKY33 could coordinately induce the expressions of OfTPS7, 1-deoxy-d-xylulose 1 (OfDXS1), thereby promoting the linalool formation. The results first revealed the hub linalool synthase gene OfTPS7 and a novel TF participating in the complex transcriptional regulation of linalool biosynthesis in O. fragrans flowers.

biochemistry↗

Mosaic integration of spatial multi-omics with SpaMosaic

With the advent of spatial multi-omics, mosaic integration of diverse datasets with partially overlapping modalities enables construction of comprehensive multi-modal spatial atlases from heterogeneous sources. Here, we present SpaMosaic, a tool that employs contrastive learning and graph neural networks to build a modality-agnostic and batch-corrected latent space for spatial domain identification and missing modality imputation. We systematically benchmarked SpaMosaic against existing integration methods using simulated data and experimentally acquired datasets spanning RNA and protein abundance, chromatin accessibility, and histone modifications from brain, embryo, tonsil, and lymph node tissues. SpaMosaic consistently outperformed other methods in identifying coherent spatial domains by reducing noise and mitigating batch effects across diverse technologies and developmental stages. Computationally, SpaMosaic is highly scalable, capable of integrating over 100 sections and processing a single section with more than 800,000 spots. Beyond robust integration, the unified latent space generated by SpaMosaic enables accurate imputation of missing modalities. In a mosaic mouse brain dataset, the imputed histone modifications not only recapitulated expected transcriptome-epigenome correlations but also uncovered more region-specific regulatory links compared to the measured chromatin accessibility data, demonstrating the ability to infer relationships between modalities without co-profiling. In summary, SpaMosaic provides a versatile framework for unifying the rapidly accumulating heterogeneous spatial omics data into comprehensive biological atlases.

bioinformatics↗