Biology subjects

Gao, Y.

Publications and source records attributed to Gao, Y..

At least 379 records · Page 21Linked to original sources

bioRxiv2023

Endothelial cell-derived lactate triggers mesenchymal stem cell histone lactylation to attenuate osteoporosis

Blood vessels play a role in osteogenesis and osteoporosis; however, the role of vascular metabolism is unclear. The present study found that ovariectomized mice exhibit reductions in bone blood vessel density and expression of endothelial glycolytic regulator pyruvate kinase M2 (PKM2). Additional data showed that endothelial cell (EC)-specific deletion of Pkm2 impair osteogenesis and worsen osteoporosis in mice. This was attributed to the impaired differentiation ability toward osteoblast of bone mesenchymal stem cells (BMSCs). Mechanistically, EC-specific deletion of Pkm2 reduce serum lactate levels secreted by ECs, which affect histone lactylation of BMSCs. We identified collagen type I alpha 2 chain, cartilage oligomeric matrix protein, ectonucleotide pyrophosphatase/phosphodiesterase 1, and transcription factor 7 like 2 as histone H3K18 lactylation-regulated osteogenic genes using joint CUT&Tag and RNA-sequencing analyses. The overexpression of PKM2 in ECs, addition of lactate, and exercise were observed to restore the phenotype of endothelial Pkm2-deficient mice. Furthermore, metabolomics of the serum indicated that osteoporosis patients showed a relatively low lactate level. The histone lactylation and related osteogenic genes of BMSCs in osteoporosis patients also decreased. In conclusion, the glycolysis of ECs fuels the differentiation of BMSCs into osteoblasts through histone lactylation, and exercise partially ameliorates osteoporosis through increased serum lactate.

cell biology↗

bioRxiv2023

Changes in the urine proteome after massage in healthy people

This study aimed to explore the effect of massage on the urine proteome of healthy people. In this study, participants underwent 1-hour whole body massage. Urine samples were collected at 0, 2, and 24h after the massage and urine proteins were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Compared with the control (before massage), 41 differential proteins were identified in the group 2h after the massage, the random mean number of differentially produced proteins was 11 with 73% confidence, and the biological process of protein enrichment was catecholamine biosynthesis, which was related to the promotion of metabolism and the regulation of neural activities. While 29 differential proteins were identified in the group 24h after the massage, the random average number of differential proteins produced was 10, with the confidence of the difference decreased to 65%, and the effective biological process could not be enriched at this time. The results suggested that the difference in urine protein was greater at 2h after the massage and gradually decreased at 24h after the massage. The proteome of urine may reflect changes in the body following minor massage stimuli, providing a potential way to evaluate the effects of massage therapy.

biochemistry↗

bioRxiv2023

Dynamic functional connectivity MEG features of Alzheimer's disease

Dynamic resting state functional connectivity (RSFC) characterizes time-varying fluctuations of functional brain network activity. While many studies have investigated static functional connectivity, it has been unclear whether features of dynamic functional connectivity are associated with neurodegenerative diseases. Popular sliding-window and clustering methods for extracting dynamic RSFC have various limitations that prevent extracting reliable features to address this question. Here, we use a novel and robust time-varying dynamic network (TVDN) approach to extract the dynamic RSFC features from high resolution magnetoencephalography (MEG) data of participants with Alzheimers disease (AD) and matched controls. The TVDN algorithm automatically and adaptively learns the low-dimensional spatiotemporal manifold of dynamic RSFC and detects dynamic state transitions in data. We show that amongst all the functional features we investigated, the dynamic manifold features are the most predictive of AD. These include: the temporal complexity of the brain network, given by the number of state transitions and their dwell times, and the spatial complexity of the brain network, given by the number of eigenmodes. These dynamic features have high sensitivity and specificity in distinguishing AD from healthy subjects. Intriguingly, we found that AD patients generally have higher spatial complexity but lower temporal complexity compared with healthy controls. We also show that graph theoretic metrics of dynamic component of TVDN are significantly different in AD versus controls, while static graph metrics are not statistically different. These results indicate that dynamic RSFC features are impacted in neurodegenerative disease like Alzheimers disease, and may be crucial to understanding the pathophysiological trajectory of these diseases.

neuroscience↗

bioRxiv2023

Whole-brain, gray and white matter time-locked functional signal changes with simple tasks and model-free analysis

Recent studies have revealed the production of time-locked blood oxygenation-level dependent (BOLD) functional MRI (fMRI) signals throughout the entire brain in response to a task, challenging the idea of sparse and localized brain functions, and highlighting the pervasiveness of potential false negative fMRI findings. In these studies, whole-brain refers to gray matter regions only, which is the only tissue traditionally studied with fMRI. However, recent reports have also demonstrated reliable detection and analyses of BOLD signals in white matter which have been largely ignored in previous reports. Here, using model-free analysis and simple tasks, we investigate BOLD signal changes in both white and gray matters. We aimed to evaluate whether white matter also displays time-locked BOLD signals across all structural pathways in response to a stimulus. We find that both white and gray matter show time-locked activations across the whole-brain, with a majority of both tissue types showing statistically significant signal changes for all task stimuli investigated. We observed a wide range of signal responses to tasks, with different regions showing very different BOLD signal changes to the same task. Moreover, we find that each region may display different BOLD responses to different stimuli. Overall, we present compelling evidence that the whole brain, including both white and gray matter, show time-locked activation to multiple stimuli, not only challenging the idea of sparse functional localization, but also the prevailing wisdom of treating white matter BOLD signals as artefacts to be removed.

neuroscience↗

bioRxiv2023

A non-canonical function of LDHB promotes SLC7A11-mediated glutathione metabolism and protects against glutaminolysis-dependent ferroptosis in KRAS-driven lung cancer

Ferroptosis, a form of non-apoptotic cell death program driven by excessive lipid peroxidation and an important mechanism of tumor suppression, is frequently dysregulated in cancer. However, the mechanisms underlying impaired ferroptosis in oncogene-specific tumors remain poorly understood. Here we report a non- canonical role of lactate dehydrogenase B (LDHB), whose main activity is the conversion of lactate to pyruvate, in protecting KRAS-mutated lung cancer from ferroptosis. Silencing of LDHB impairs intracellular glutathione (GSH) metabolism and drives the hypersensitivity of KRAS-mutant cells to ferroptosis inducers by inhibiting the SLC7A11/GSH/GPX4 axis, a central antioxidant system against lipid peroxidation and ferroptosis by catalyzing GSH synthesis and utilization. Mechanistically, LDHB promotes SLC7A11 expression and GSH biosynthesis, and inhibition of LDHB confers metabolic synthetic lethality with ferroptosis inducers due to increased glutaminolysis and production of reactive oxygen species (ROS) in mitochondria, ultimately triggering ferroptosis of KRAS-driven lung cancer cells. Consequently, combined inhibition of LDHB and SLC7A11 synergistically suppresses tumor growth in multiple KRAS-mutant lung cancer implants and in an autochthonous model of Kras-induced lung adenocarcinoma. Taken together, our results reveal a hitherto unrecognized mechanism of ferroptosis defense by glycolytic LDHB and suggest a new strategy for the treatment of KRAS-dependent lung cancer.

cancer biology↗

bioRxiv2023

FarmGTEx TWAS-server: an interactive web server for customized TWAS analysis in both human and farm animals

Transcriptome-wide association study (TWAS) is a powerful strategy for elucidating the molecular mechanisms behind the genetic loci of complex phenotypes. However, TWAS analysis is still daunting in many species due to the complication of the TWAS analysis pipeline, including the construction of the gene expression reference panel, gene expression prediction, and the subsequent association analysis in the large cohorts of genome-wide association study (GWAS). Farm animals are major protein sources and biomedical models for humans. To facilitate the translation of genetic findings across species, here we provide an interactive and easy-to-use multi-species TWAS web server for the entire community, called the FarmGTEx TWAS-server (http://twas.farmgtex.org), which is based on the GTEx and FarmGTEx projects. It includes gene expression data from 49, 34, and 23 tissues in 838 humans, 5,457 pigs, and 4,889 cattle, representing 38,180, 21,037, and 17,942 distinct eGenes in prediction models for humans, pigs, and cattle, respectively. It allows users to conduct gene expression prediction for any individuals with genotypes, GWAS summary statistics imputation, customized TWAS, and popular downstream functional annotation. It also provides 479,203, 1,208, and 657 tissue-gene-trait association trios for the research community, representing 1,129 human traits, 41 cattle traits, and 11 pig traits. In summary, the FarmGTEx TWAS-server is a one-stop solution for performing TWAS analysis for researchers without programming skills in both human and farm animal research communities. It will be maintained and updated timely within the FarmGTEx project to facilitate gene mapping and phenotype prediction within and across species.

bioinformatics↗

bioRxiv2023

Phage-specific immune responses impair efficacy of phage therapy targeting VRE in a murine model

Antimicrobial resistant bacteria are an emerging and prevalent global threat with an urgent need for alternative therapies. Bacteriophage (phage) therapy is a promising approach to address these infections that has gained renewed interest in recent years. Despite this, questions remain regarding the therapeutic use of phages, including the impact that the immune response may have on phage therapy, particularly when this treatment is administered long-term or when reusing a specific phage treatment in a single individual. To investigate this, we developed a mouse model to assess phage treatment using a cocktail of five phages from the Myoviridae and Siphoviridae families that target vancomycin-resistant enterococcus (VRE) gut colonization. Phage cocktail treatment significantly reduced the intestinal bacterial burden of VRE in mice. We characterized innate and adaptive immune responses elicited against the phage cocktail after one and multiple exposures, respectively. While minimal innate responses were observed after phage administration, two courses of phage therapy induced phage-specific neutralizing antibodies and appeared to accelerate phage clearance from tissues. Interestingly, the myophages in our cocktail induced a more robust neutralizing antibody response than the siphophages. Proteins targeted by phage-specific antibodies were also identified from each phage family of the cocktail. Importantly, we show that this anti-phage immunity reduced the effectiveness of the phage cocktail in our murine model, leading to significantly higher fecal bacterial burden following repeat treatment. Collectively, this study shows the immune system has the potential to impede effectiveness of phage therapy and that the phage-specific immune responses can differ significantly between phages. These findings can help inform decisions about inclusion of specific phages in cocktails for future studies.

immunology↗

bioRxiv2022

Molecular insights into the gating mechanisms of voltage-gated calcium channel CaV2.3

High-voltage-activated R-type CaV2.3 channel plays pivotal roles in many physiological activities and is implicated in epilepsy, convulsions, and other neurodevelopmental impairments. Here, we determine the high-resolution cryo-electron microscopy (cryo-EM) structure of human CaV2.3 in complex with the 2{delta}1 and {beta}1 subunits. The VSDII is stabilized in the resting state. Electrophysiological experiments elucidate that the conformational change of VSDII in response to variation in membrane potential is not required for channel activation, whereas the other VSDs are essential for channel opening. The intracellular gate is blocked by the W-helix. A pre-W-helix adjacent to the W-helix can significantly regulate closed-state inactivation (CSI) by modulating the association and dissociation of the W-helix with the gate. Electrostatic interactions formed between the negatively charged domain on S6II, which is exclusively conserved in the CaV2 family, and nearby regions at the alpha-interacting domain (AID) and S4-S5II helix are identified. Further functional analyses indicate that these interactions are critical for the open-state inactivation (OSI) of CaV2 channels.

biophysics↗

bioRxiv2022

SARS-CoV-2 causes periodontal fibrosis by deregulating mitochondrial beta-oxidation

The global high prevalence of COVID-19 is a major challenge for health professionals and patients. SARS-CoV-2 virus mutate predominantly in the spike proteins, whilst the other key viral components remain stable. Previous studies have shown that the human oral cavity can potentially act as reservoir of the SARS-CoV-2 virus. COVID-19 can cause severe oral mucosa lesions and is likely to be connected with poor periodontal conditions. However, the consequence of SARS-CoV-2 viral infection on human oral health has not been systematically examined. In this research, we aimed to study the pathogenicity of SARS-CoV-2 viral components on human periodontal tissues and cells. We found that by exposing to SARS-CoV-2, especially to the viral envelope and membrane proteins, the human periodontal fibroblasts could develop fibrotic pathogenic phenotypes, including hyperproliferation that was concomitant induced together with increased apoptosis and senescence. The fibrotic degeneration was mediated by a down-regulation of mitochondrial {beta}-oxidation in the fibroblasts. Fatty acid {beta}-oxidation inhibitor, etomoxir treatment could mirror the same pathological consequence on the cells, similar to SARS- CoV-2 infection. Our results therefore provide novel mechanistic insights into how SARS- CoV-2 infection can affect human periodontal health at the cell and molecular level with potential new therapeutic targets for COVID-19 induced fibrosis.

molecular biology↗

bioRxiv2022

Transcriptomic landscape and potential therapeutic targets for human testicular aging revealed by single-cell RNA sequencing

BackgroundTesticular aging is known to cause male age-related fertility decline and hypogonadism, but the underlying molecular mechanisms remain unclear. MethodsWe survey the single-cell transcriptomic landscape of testes from young and old men and examine age-related changes in germline and somatic niche cells. ResultsIn-depth evaluation of the gene expression dynamics of germline cells reveals that disturbance of base-excision repair pathway is a major feature of aging spermatogonial stem cells (SSCs), suggesting that defective DNA repair of SSCs may serve as a potential driver for increased de novo germline mutations with age. Further analysis of aging-associated transcriptional changes shows that stress-related changes and apoptotic signaling pathway accumulate in aged somatic cells. We identify age-related impairment of redox homeostasis in aged Leydig cells and find that pharmacological treatment with antioxidants alleviate this cellular dysfunction of Leydig cells and promote testosterone production. Lastly, our results reveal that decreased pleiotrophin (PTN) signaling is a contributing factor for testicular aging. ConclusionsThese findings provide a comprehensive understanding of the cell-type-specific mechanisms underlying human testicular aging at a single-cell resolution, and suggest potential therapeutic targets that may be leveraged to address age-related male fertility decline and hypogonadism. FundingThis work was supported by the National Key Research and Development Program of China (2018YFA0107200, 2018YFA0801404), the National Natural Science Foundation of China (32130046, 82171564, 82101669, 81871110, 81971759), the Key Research and Development Program of Guangdong Province (2019B020234001), the Natural Science Foundation of Guangdong Province, China (2022A1515010371), the Major Project of Medical Science and Technology Development Research Center of National Health Planning Commission, China (HDSL202001000), the Open Project of NHC Key Laboratory of Male Reproduction and Genetics (Family Planning Research Institute of Guangdong Province) (KF202001), the Guangdong Province Regional Joint Fund-Youth Fund Project (2021A1515110921), the China Postdoctoral Science Foundation (2021M703736).

developmental biology↗

bioRxiv2022

Fortuitous Somatic Mutations during Antibody Evolution Endow Broad Neutralization against SARS-CoV-2 Omicron Variants

Striking antibody evasion by emerging circulating SARS-CoV-2 variants drives the identification of broadly neutralizing antibodies (bNAbs). However, how a bNAb acquires increased neutralization breadth during antibody evolution is still elusive. Here, we identified a clonally-related antibody family from a convalescent individual. One of the members, XG005, exhibited potent and broad neutralizing activities against SARS-CoV-2 variants, while the other members showed significant reductions in neutralization breadth and potency, especially against the Omicron sublineages. Structural analysis visualizing the XG005-Omicron spike binding interface revealed how crucial somatic mutations endowed XG005 with greater neutralization potency and breadth. A single administration of XG005 with extended half-life, reduced antibody-dependent enhancement (ADE) effect, and increased antibody product quality, exhibited a high therapeutic efficacy in BA.2- and BA.5-challenged mice. Our results provided a natural example to show the importance of somatic hypermutation during antibody evolution for SARS-CoV-2 neutralization breadth and potency.

immunology↗

bioRxiv2022

Observation of the dynamic changes in the urinary proteome in rats during immunization

ObjectiveChanges in the immune system in the urine proteome were observed by injecting bovine serum albumin and aluminum hydroxide adjuvant into rats. MethodsIn this study, bovine serum albumin and aluminum hydroxide adjuvant were injected into rat thigh muscle, urine was collected, differential proteins were identified by liquid chromatography--mass spectrometry (LC--MSMS/MS), and biological pathways of differential proteins were analyzed by IPA software to observe the changes in the immune system as evidenced by rat urinary proteins. ResultsFifteen rats were intramuscularly injected with normal saline, aluminum hydroxide adjuvant, bovine serum albumin, aluminum hydroxide adjuvant, and bovine serum albumin (BSA) mixture to construct the models of the control, adjuvant, BSA, and mixed groups. Upon comparing the different proteins between different groups to obtain the relevant biological pathways, it was found that adjuvants can be observed in urine to help bovine serum albumin stimulate the immune system to respond earlier. It was also observed in urine that the mixed group successively stimulated immune-related pathways, such as the inflammatory response, T-cell activation, antigen-presenting cell-related pathways, and B-cell-related pathways. DiscussionWe can observe changes in the immune system from the urine proteome in the early stage, providing some new clues and a basis for future research on the immune system and accelerating vaccine research and development.

biochemistry↗

bioRxiv2022

Structural Model for Self-Limiting β-strand Arrangement Within an Alzheimer's Amyloid-β Oligomer

Previous reports revealed that sodium dodecyl sulfate near its critical micelle concentration can drive the assembly of A{beta}42 along an oligomeric pathway. This pathway produces a 150 kDa peptide oligomer (approximately 32 peptide molecules or protomers) that does not aggregate further into amyloid fibrils. Solid-state nuclear magnetic resonance (NMR) spectroscopy revealed structural features distinguishing the 150 kDa oligomer from fibrils. A puzzling feature was the coexistence of parallel and antiparallel {beta}-sheets within the oligomer structure. Here we present new atomic-level structural constraints obtained via solid-state NMR spectroscopy, benefitting from improved resolution via sample concentration by ultracentrifugation. In addition, two-dimensional cryo-electron microscopy (cryo-EM) reconstruction revealed a 4-fold symmetric shape. We propose a structural model to rationalize the solid-sate NMR- and cryo-EM-derived structural constraints. This model has a hollow square cylinder shape, with antiparallel {beta}-sheets formed by residues 33-39 lining the inner walls and parallel {beta}-sheets formed by residues 11-22 lining the outer walls. Within successive layers, the outer {beta}-strands on each side of the square cylinder alternate between two forms: one within a U-shaped protomer and another within L-shaped protomer. Molecular dynamics simulations show that, when the oligomer model is embedded in a lipid membrane, ions permeate through the central pore, with cation selectivity. The model further motivates an assembly pathway-based interpretation that may explain why the 150 kDa oligomer does not undergo further aggregation into amyloid fibrils. Significance StatementA{beta} oligomers are thought to be the most toxic species in Alzheimers disease. Their sizes range from 2 to [~]50 protomers. Most published experimental data on A{beta} oligomers indicate that they, like fibrils, are composed of {beta}-sheets, but it is a mystery why any {beta}-sheet aggregate would exist as a stable oligomer without undergoing further aggregation into fibrils. Here, structural constraints from solid-state NMR and cryo-EM led us to an oligomer model with a hollow square cylinder shape capable of conducting ions when embedded in a lipid membrane. Based on the model, we argue that geometric frustration may distinguish the assembly pathway that produces this oligomer from fibril-forming assembly pathways.

biochemistry↗

bioRxiv2022

Comparative genomic analysis between Leonurus japonicus and Leonurus sibiricus

Leonurus japonicus Houtt. is an important medicinal plant in East Asia and is now widely recognized for its role in treating cerebral apoplexy and lowering blood lipids. Here, we report two sets of chromosome-level genome sequences for leonurine-producing Leonurus japonicus and for its closely related species leonurine-free Leonurus sibiricus, where 99.78% of 518.19 Mb of L. japonicus was assembled into ten pseudochromosomes with a contig N50 of 17.62 Mb and 99.33% of 472.29 Mb of L. sibiricus was assembled into nine pseudochromosomes with a contig N50 of 13.29 MB. The reference genomes of Leonurus will accelerate the decoding of novel bioactive molecules in medicinal plants, especially in the Lamiaceae family.

plant biology↗

bioRxiv2022

Accurate prediction of cohesin-mediated 3D genome organization from 2D chromatin features

The three-dimensional (3D) genome organization influences diverse nuclear processes. Chromatin interaction analysis by paired-end tag sequencing (ChIA-PET) and Hi-C are powerful methods to study the 3D genome organization. However, ChIA-PET and Hi-C experiments are expensive, time-consuming, require tens to hundreds of millions of cells, and are challenging to optimize and analyze. Predicting ChIA-PET/Hi-C data using cheaper ChIP-Seq data and other easily obtainable features could be a useful alternative. It is well-established that the cohesin protein complex is a key determinant of 3D genome organization. Here we present Chromatin Interaction Predictor (ChIPr), a suite of regression models based on deep neural networks (DNN), random forest, and gradient boosting, respectively, to predict cohesin-mediated chromatin interaction strength between any two loci in the genome. Comprehensive tests on four cell lines show that the predictions of ChIPr correlate well with the original ChIA-PET data at the peak-level resolution and bin sizes of 25 and 5 Kbp. In addition, ChIPr can accurately capture most of the cell-type-dependent loops identified by ChIA-PET and Hi-C data. Rigorous feature testing indicated that genomic distance and RAD21 (a cohesin component) ChIP-Seq signals are the most important inputs for ChIPr in determining chromatin interaction strength. The standard ChIPr model requires three experimental inputs: ChIP-Seq signals for RAD21, H3K27ac (enhancer/active chromatin mark) and H3K27me3 (inactive chromatin mark). The minimal ChIPr model performs comparably and requires a single experimental input: ChIP-Seq signals for RAD21. Integrative analysis revealed novel insights into the role of CTCF motif, its orientation, and CTCF binding on the prevalence and strength of cohesin-mediated chromatin interactions. These studies outline the general features of genome folding and open new avenues to analyze spatial genome organization in specimens with limited cell numbers.

genomics↗

bioRxiv2022

A non-invasive, fast on/off 'Odourgenetic' Method to Manipulate Physiology

Manipulating molecular processes governing physiological functions has significant potential for clinical therapeutics and is an important approach to elucidate the cellular basis of physiological functions. Here, we designed a Odourgenetic system co-expressed Drosophila odorant receptor system (DORs) consisting of OR35a and OR83b, which were exclusively activated by their odor ligand, 2-pentanone. Applying 2-pentanone to DOR-expressing cells or tissues induced calcium influx and membrane depolarization. By inhalation of 2-pentanone, we successfully applied DORs to manipulate behaviour, control insulin secretion and regulate blood glucose and manipulate muscle contraction and associated limb movement. Because 2-pentanone rapidly enters the blood upon inhalation and leaves the body by exhalation, this odorant can be used with DORs to manipulate cellular function, and the manipulation can be terminated at any time. Such feature approach significantly improves the safety and controllability of DORs used in the clinic. Thus, the present study developed a non-invasive, controllable, fast on/off method to manipulate cellular activity and behaviour on a time scale of minutes.

cell biology↗

bioRxiv2022

Urine proteomic analysis of the rat startle model

Urine proteomics was applied to explore whether the effect of startle can be detected in urine. A combination of natural enemy odor and sound stimulation was used to establish the rat startle model. Urine samples were collected before and after startle, and urine proteomes before-after startle of each rat were compared individually. Regulatory subunits of glutamate-cysteine ligase was identified as the sole differential protein among all five startled rats. To our surprise, its functional partner catalytic subunits of glutamate-cysteine ligase was also identified in four out of five rats as differential protein. When comparing before-after startle as two groups, 22 differential proteins were identified which represent biological pathways including neurotransmitter transport and glucose transmembrane transport.

biochemistry↗

bioRxiv2022

Urine proteomic analysis of the rat e-cigarette model

Urinary proteomics was used to investigate the potential effects of e-cigarettes on the human body. In this study, a rat e-cigarette model was constructed by smoking for two weeks and urine samples before, during, and after e-cigarette smoking were collected. Urine proteomes before-after smoking of each rat were compared individually, while the control group was set up to rule out differences caused by rat growth and development. After smoking, the differential proteins produced by rats shows strong individual variation. Fetuin-B, a biomarker of COPD, and annexin A2, which is recognized as a multiple tumor marker, were identified as the differential proteins in five out of six smoking rats on day 3. To our surprise, odorant-binding proteins expressed in the olfactory epithelium were also found and were significantly upregulated, which may help explain olfactory adaptation. Pathways enriched by the differential proteins shows the evidence that smoking e-cigarettes affects the immune system, cardiovascular system, respiratory system, etc., which provides clues for further exploration of the mechanism of e-cigarettes on the human body.

biochemistry↗