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1.
Nature ; 631(8022): 899-904, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38838737

RÉSUMÉ

Synaptic vesicles are organelles with a precisely defined protein and lipid composition1,2, yet the molecular mechanisms for the biogenesis of synaptic vesicles are mainly unknown. Here we discovered a well-defined interface between the synaptic vesicle V-ATPase and synaptophysin by in situ cryo-electron tomography and single-particle cryo-electron microscopy of functional synaptic vesicles isolated from mouse brains3. The synaptic vesicle V-ATPase is an ATP-dependent proton pump that establishes the proton gradient across the synaptic vesicle, which in turn drives the uptake of neurotransmitters4,5. Synaptophysin6 and its paralogues synaptoporin7 and synaptogyrin8 belong to a family of abundant synaptic vesicle proteins whose function is still unclear. We performed structural and functional studies of synaptophysin-knockout mice, confirming the identity of synaptophysin as an interaction partner with the V-ATPase. Although there is little change in the conformation of the V-ATPase upon interaction with synaptophysin, the presence of synaptophysin in synaptic vesicles profoundly affects the copy number of V-ATPases. This effect on the topography of synaptic vesicles suggests that synaptophysin assists in their biogenesis. In support of this model, we observed that synaptophysin-knockout mice exhibit severe seizure susceptibility, suggesting an imbalance of neurotransmitter release as a physiological consequence of the absence of synaptophysin.


Sujet(s)
Synaptophysine , Vacuolar Proton-Translocating ATPases , Animaux , Mâle , Souris , Cryomicroscopie électronique , Souris knockout , Modèles moléculaires , Agents neuromédiateurs/métabolisme , Liaison aux protéines , Crises épileptiques/génétique , Crises épileptiques/métabolisme , Vésicules synaptiques/composition chimique , Vésicules synaptiques/enzymologie , Vésicules synaptiques/ultrastructure , Synaptophysine/composition chimique , Synaptophysine/déficit , Synaptophysine/métabolisme , Synaptophysine/ultrastructure , Vacuolar Proton-Translocating ATPases/analyse , Vacuolar Proton-Translocating ATPases/composition chimique , Vacuolar Proton-Translocating ATPases/métabolisme , Vacuolar Proton-Translocating ATPases/ultrastructure , Tomographie en microscopie électronique
2.
Nat Med ; 30(5): 1448-1460, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38760586

RÉSUMÉ

In a previous study, heart xenografts from 10-gene-edited pigs transplanted into two human decedents did not show evidence of acute-onset cellular- or antibody-mediated rejection. Here, to better understand the detailed molecular landscape following xenotransplantation, we carried out bulk and single-cell transcriptomics, lipidomics, proteomics and metabolomics on blood samples obtained from the transplanted decedents every 6 h, as well as histological and transcriptomic tissue profiling. We observed substantial early immune responses in peripheral blood mononuclear cells and xenograft tissue obtained from decedent 1 (male), associated with downstream T cell and natural killer cell activity. Longitudinal analyses indicated the presence of ischemia reperfusion injury, exacerbated by inadequate immunosuppression of T cells, consistent with previous findings of perioperative cardiac xenograft dysfunction in pig-to-nonhuman primate studies. Moreover, at 42 h after transplantation, substantial alterations in cellular metabolism and liver-damage pathways occurred, correlating with profound organ-wide physiological dysfunction. By contrast, relatively minor changes in RNA, protein, lipid and metabolism profiles were observed in decedent 2 (female) as compared to decedent 1. Overall, these multi-omics analyses delineate distinct responses to cardiac xenotransplantation in the two human decedents and reveal new insights into early molecular and immune responses after xenotransplantation. These findings may aid in the development of targeted therapeutic approaches to limit ischemia reperfusion injury-related phenotypes and improve outcomes.


Sujet(s)
Transplantation cardiaque , Hétérogreffes , Transplantation hétérologue , Humains , Animaux , Suidae , Mâle , Femelle , Rejet du greffon/immunologie , Rejet du greffon/génétique , Protéomique , Métabolomique , Agranulocytes/métabolisme , Agranulocytes/immunologie , Transcriptome , Analyse de profil d'expression de gènes , Lymphocytes T/immunologie , Lymphocytes T/métabolisme , Lipidomique , Lésion d'ischémie-reperfusion/immunologie , Lésion d'ischémie-reperfusion/génétique , Lésion d'ischémie-reperfusion/métabolisme , Multi-omique
3.
Cell Host Microbe ; 32(4): 506-526.e9, 2024 Apr 10.
Article de Anglais | MEDLINE | ID: mdl-38479397

RÉSUMÉ

To understand the dynamic interplay between the human microbiome and host during health and disease, we analyzed the microbial composition, temporal dynamics, and associations with host multi-omics, immune, and clinical markers of microbiomes from four body sites in 86 participants over 6 years. We found that microbiome stability and individuality are body-site specific and heavily influenced by the host. The stool and oral microbiome are more stable than the skin and nasal microbiomes, possibly due to their interaction with the host and environment. We identify individual-specific and commonly shared bacterial taxa, with individualized taxa showing greater stability. Interestingly, microbiome dynamics correlate across body sites, suggesting systemic dynamics influenced by host-microbial-environment interactions. Notably, insulin-resistant individuals show altered microbial stability and associations among microbiome, molecular markers, and clinical features, suggesting their disrupted interaction in metabolic disease. Our study offers comprehensive views of multi-site microbial dynamics and their relationship with host health and disease.


Sujet(s)
Stabilité centrale , Microbiote , Humains , Peau/microbiologie , Interactions hôte-microbes , Marqueurs biologiques
4.
bioRxiv ; 2024 Feb 01.
Article de Anglais | MEDLINE | ID: mdl-38352363

RÉSUMÉ

To understand dynamic interplay between the human microbiome and host during health and disease, we analyzed the microbial composition, temporal dynamics, and associations with host multi-omics, immune and clinical markers of microbiomes from four body sites in 86 participants over six years. We found that microbiome stability and individuality are body-site-specific and heavily influenced by the host. The stool and oral microbiome were more stable than the skin and nasal microbiomes, possibly due to their interaction with the host and environment. Also, we identified individual-specific and commonly shared bacterial taxa, with individualized taxa showing greater stability. Interestingly, microbiome dynamics correlated across body sites, suggesting systemic coordination influenced by host-microbial-environment interactions. Notably, insulin-resistant individuals showed altered microbial stability and associations between microbiome, molecular markers, and clinical features, suggesting their disrupted interaction in metabolic disease. Our study offers comprehensive views of multi-site microbial dynamics and their relationship with host health and disease. Study Highlights: The stability of the human microbiome varies among individuals and body sites.Highly individualized microbial genera are more stable over time.At each of the four body sites, systematic interactions between the environment, the host and bacteria can be detected.Individuals with insulin resistance have lower microbiome stability, a more diversified skin microbiome, and significantly altered host-microbiome interactions.

5.
Commun Biol ; 6(1): 1053, 2023 10 18.
Article de Anglais | MEDLINE | ID: mdl-37853211

RÉSUMÉ

Genetic variation accounts for much of the risk for developing a substance use disorder, but the underlying genetic factors and their genetic effector mechanisms are mostly unknown. Inbred mouse strains exhibit substantial and heritable differences in the extent of voluntary cocaine self-administration. Computational genetic analysis of cocaine self-administration data obtained from twenty-one inbred strains identified Nav1, a member of the neuron navigator family that regulates dendrite formation and axonal guidance, as a candidate gene. To test this genetic hypothesis, we generated and characterized Nav1 knockout mice. Consistent with the genetic prediction, Nav1 knockout mice exhibited increased voluntary cocaine intake and had increased motivation for cocaine consumption. Immunohistochemistry, electrophysiology, and transcriptomic studies were performed as a starting point for investigating the mechanism for the Nav1 knockout effect. Nav1 knockout mice had a reduced inhibitory synapse density in their cortex, increased excitatory synaptic transmission in their cortex and hippocampus, and increased excitatory neurons in a deep cortical layer. Collectively, our results indicate that Nav1 regulates the response to cocaine, and we identified Nav1 knockout induced changes in the excitatory and inhibitory synaptic balance in the cortex and hippocampus that could contribute to this effect.


Sujet(s)
Cocaïne , Souris , Animaux , Cocaïne/pharmacologie , Transmission synaptique , Neurones , Souris knockout , Hippocampe
6.
Nature ; 608(7922): 353-359, 2022 08.
Article de Anglais | MEDLINE | ID: mdl-35922509

RÉSUMÉ

Regulation of transcript structure generates transcript diversity and plays an important role in human disease1-7. The advent of long-read sequencing technologies offers the opportunity to study the role of genetic variation in transcript structure8-16. In this Article, we present a large human long-read RNA-seq dataset using the Oxford Nanopore Technologies platform from 88 samples from Genotype-Tissue Expression (GTEx) tissues and cell lines, complementing the GTEx resource. We identified just over 70,000 novel transcripts for annotated genes, and validated the protein expression of 10% of novel transcripts. We developed a new computational package, LORALS, to analyse the genetic effects of rare and common variants on the transcriptome by allele-specific analysis of long reads. We characterized allele-specific expression and transcript structure events, providing new insights into the specific transcript alterations caused by common and rare genetic variants and highlighting the resolution gained from long-read data. We were able to perturb the transcript structure upon knockdown of PTBP1, an RNA binding protein that mediates splicing, thereby finding genetic regulatory effects that are modified by the cellular environment. Finally, we used this dataset to enhance variant interpretation and study rare variants leading to aberrant splicing patterns.


Sujet(s)
Allèles , Analyse de profil d'expression de gènes , Spécificité d'organe , RNA-Seq , Transcriptome , Épissage alternatif/génétique , Lignée cellulaire , Jeux de données comme sujet , Génotype , Ribonucléoprotéines nucléaires hétérogènes/déficit , Ribonucléoprotéines nucléaires hétérogènes/génétique , Humains , Spécificité d'organe/génétique , Protéine PTB/déficit , Protéine PTB/génétique , Reproductibilité des résultats , Transcriptome/génétique
7.
Cell Rep ; 40(9): 111264, 2022 08 30.
Article de Anglais | MEDLINE | ID: mdl-36044843

RÉSUMÉ

As our closest living relatives, non-human primates uniquely enable explorations of human health, disease, development, and evolution. Considerable effort has thus been devoted to generating induced pluripotent stem cells (iPSCs) from multiple non-human primate species. Here, we establish improved culture methods for chimpanzee (Pan troglodytes) and pig-tailed macaque (Macaca nemestrina) iPSCs. Such iPSCs spontaneously differentiate in conventional culture conditions, but can be readily propagated by inhibiting endogenous WNT signaling. As a unique functional test of these iPSCs, we injected them into the pre-implantation embryos of another non-human species, rhesus macaques (Macaca mulatta). Ectopic expression of gene BCL2 enhances the survival and proliferation of chimpanzee and pig-tailed macaque iPSCs within the pre-implantation embryo, although the identity and long-term contribution of the transplanted cells warrants further investigation. In summary, we disclose transcriptomic and proteomic data, cell lines, and cell culture resources that may be broadly enabling for non-human primate iPSCs research.


Sujet(s)
Cellules souches pluripotentes induites , Pan troglodytes , Animaux , Macaca mulatta , Macaca nemestrina/génétique , Protéomique
8.
Nat Genet ; 53(5): 638-649, 2021 05.
Article de Anglais | MEDLINE | ID: mdl-33859415

RÉSUMÉ

A central question in the post-genomic era is how genes interact to form biological pathways. Measurements of gene dependency across hundreds of cell lines have been used to cluster genes into 'co-essential' pathways, but this approach has been limited by ubiquitous false positives. In the present study, we develop a statistical method that enables robust identification of gene co-essentiality and yields a genome-wide set of functional modules. This atlas recapitulates diverse pathways and protein complexes, and predicts the functions of 108 uncharacterized genes. Validating top predictions, we show that TMEM189 encodes plasmanylethanolamine desaturase, a key enzyme for plasmalogen synthesis. We also show that C15orf57 encodes a protein that binds the AP2 complex, localizes to clathrin-coated pits and enables efficient transferrin uptake. Finally, we provide an interactive webtool for the community to explore our results, which establish co-essentiality profiling as a powerful resource for biological pathway identification and discovery of new gene functions.


Sujet(s)
Réseaux de régulation génique , Gènes , Génome , Clathrine/métabolisme , Endocytose , Épigenèse génétique , Régulation de l'expression des gènes , Cellules HeLa , Humains , Annotation de séquence moléculaire , Tumeurs/génétique , Acétalphosphatides/biosynthèse , Transduction du signal/génétique
9.
Bioinformatics ; 37(6): 815-821, 2021 05 05.
Article de Anglais | MEDLINE | ID: mdl-33098413

RÉSUMÉ

MOTIVATION: Data normalization is an important step in processing proteomics data generated in mass spectrometry experiments, which aims to reduce sample-level variation and facilitate comparisons of samples. Previously published methods for normalization primarily depend on the assumption that the distribution of protein expression is similar across all samples. However, this assumption fails when the protein expression data is generated from heterogenous samples, such as from various tissue types. This led us to develop a novel data-driven method for improved normalization to correct the systematic bias meanwhile maintaining underlying biological heterogeneity. RESULTS: To robustly correct the systematic bias, we used the density-power-weight method to down-weigh outliers and extended the one-dimensional robust fitting method described in the previous work to our structured data. We then constructed a robustness criterion and developed a new normalization algorithm, called RobNorm.In simulation studies and analysis of real data from the genotype-tissue expression project, we compared and evaluated the performance of RobNorm against other normalization methods. We found that the RobNorm approach exhibits the greatest reduction in systematic bias while maintaining across-tissue variation, especially for datasets from highly heterogeneous samples. AVAILABILITYAND IMPLEMENTATION: https://github.com/mwgrassgreen/RobNorm. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Sujet(s)
Algorithmes , Protéomique , Simulation numérique , Spectrométrie de masse , Plan de recherche
10.
J Hazard Mater ; 403: 123987, 2021 Feb 05.
Article de Anglais | MEDLINE | ID: mdl-33265026

RÉSUMÉ

Developing highly efficient and cost-effective catalyst with tuned microstructure holds great promise in the reduction of nitroaromatic compounds under mild reaction conditions. Herein, we report a new Co@NC-MF catalyst with a fascinating hierarchical flower-like architecture in situ assembled from uniform Co@NC nanoneedles, which can function as a favorable platform for the efficient reduction of nitroaromatic compounds in the presence of NaBH4. In addition with the structural advantage, the characterization and experimental results demonstrate the enormous advantage of interfacial synergistic catalysis in enhancing the catalytic performance. The outside electron-rich N-doped carbon layer as Lewis basic sites and the inside Co nanoparticles are responsible for the adsorption of 4-nitrophenol (4-NP) and generation of active hydrogen species, respectively. This work contributes to the construction of well-integrated composites with well-balanced interface synergy to boost the catalytic performance in various heterogeneous reactions.

11.
Cell ; 183(1): 269-283.e19, 2020 10 01.
Article de Anglais | MEDLINE | ID: mdl-32916130

RÉSUMÉ

Determining protein levels in each tissue and how they compare with RNA levels is important for understanding human biology and disease as well as regulatory processes that control protein levels. We quantified the relative protein levels from over 12,000 genes across 32 normal human tissues. Tissue-specific or tissue-enriched proteins were identified and compared to transcriptome data. Many ubiquitous transcripts are found to encode tissue-specific proteins. Discordance of RNA and protein enrichment revealed potential sites of synthesis and action of secreted proteins. The tissue-specific distribution of proteins also provides an in-depth view of complex biological events that require the interplay of multiple tissues. Most importantly, our study demonstrated that protein tissue-enrichment information can explain phenotypes of genetic diseases, which cannot be obtained by transcript information alone. Overall, our results demonstrate how understanding protein levels can provide insights into regulation, secretome, metabolism, and human diseases.


Sujet(s)
Protéome/génétique , Protéomique/méthodes , Transcriptome/génétique , Expression des gènes/génétique , Analyse de profil d'expression de gènes/méthodes , Humains , Protéome/physiologie , ARN/génétique , ARN messager/métabolisme , Transcriptome/physiologie
12.
Gigascience ; 9(7)2020 07 01.
Article de Anglais | MEDLINE | ID: mdl-32649757

RÉSUMÉ

BACKGROUND: Macaque species share >93% genome homology with humans and develop many disease phenotypes similar to those of humans, making them valuable animal models for the study of human diseases (e.g., HIV and neurodegenerative diseases). However, the quality of genome assembly and annotation for several macaque species lags behind the human genome effort. RESULTS: To close this gap and enhance functional genomics approaches, we used a combination of de novo linked-read assembly and scaffolding using proximity ligation assay (HiC) to assemble the pig-tailed macaque (Macaca nemestrina) genome. This combinatorial method yielded large scaffolds at chromosome level with a scaffold N50 of 127.5 Mb; the 23 largest scaffolds covered 90% of the entire genome. This assembly revealed large-scale rearrangements between pig-tailed macaque chromosomes 7, 12, and 13 and human chromosomes 2, 14, and 15. We subsequently annotated the genome using transcriptome and proteomics data from personalized induced pluripotent stem cells derived from the same animal. Reconstruction of the evolutionary tree using whole-genome annotation and orthologous comparisons among 3 macaque species, human, and mouse genomes revealed extensive homology between human and pig-tailed macaques with regards to both pluripotent stem cell genes and innate immune gene pathways. Our results confirm that rhesus and cynomolgus macaques exhibit a closer evolutionary distance to each other than either species exhibits to humans or pig-tailed macaques. CONCLUSIONS: These findings demonstrate that pig-tailed macaques can serve as an excellent animal model for the study of many human diseases particularly with regards to pluripotency and innate immune pathways.


Sujet(s)
Chromosomes , Génome , Génomique , Macaca nemestrina/génétique , Animaux , Biologie informatique/méthodes , Génomique/méthodes , Humains , Caryotypage/méthodes , Mâle , Annotation de séquence moléculaire , Protéomique/méthodes , Séquences répétées d'acides nucléiques
13.
Cell Host Microbe ; 26(4): 551-563.e6, 2019 10 09.
Article de Anglais | MEDLINE | ID: mdl-31540829

RÉSUMÉ

During infection, Legionella pneumophila translocates over 300 effector proteins into the host cytosol, allowing the pathogen to establish an endoplasmic reticulum (ER)-like Legionella-containing vacuole (LCV) that supports bacterial replication. Here, we perform a genome-wide CRISPR-Cas9 screen and secondary targeted screens in U937 human monocyte/macrophage-like cells to systematically identify host factors that regulate killing by L. pneumophila. The screens reveal known host factors hijacked by L. pneumophila, as well as genes spanning diverse trafficking and signaling pathways previously not linked to L. pneumophila pathogenesis. We further characterize C1orf43 and KIAA1109 as regulators of phagocytosis and show that RAB10 and its chaperone RABIF are required for optimal L. pneumophila replication and ER recruitment to the LCV. Finally, we show that Rab10 protein is recruited to the LCV and ubiquitinated by the effectors SidC/SdcA. Collectively, our results provide a wealth of previously undescribed insights into L. pneumophila pathogenesis and mammalian cell function.


Sujet(s)
Legionella pneumophila/pathogénicité , Maladie des légionnaires/anatomopathologie , Phagocytose/immunologie , Protéines/génétique , Vacuoles/microbiologie , Animaux , Protéines bactériennes/métabolisme , Lignée cellulaire , Clustered regularly interspaced short palindromic repeats/génétique , Réticulum endoplasmique/métabolisme , Facteurs d'échange de nucléotides guanyliques/génétique , Facteurs d'échange de nucléotides guanyliques/métabolisme , Cellules HEK293 , Cellules HeLa , Humains , Legionella pneumophila/génétique , Macrophages/métabolisme , Macrophages/microbiologie , Protéines membranaires/génétique , Protéines membranaires/métabolisme , Souris , Cellules RAW 264.7 , Cellules U937 , Facteurs de virulence/génétique , Protéines G rab/génétique , Protéines G rab/métabolisme
14.
J Mol Model ; 25(3): 71, 2019 Feb 20.
Article de Anglais | MEDLINE | ID: mdl-30788646

RÉSUMÉ

A computational study of cyclohexane autoxidation and catalytic oxidation to a cyclohexyl hydroperoxide intermediate (CyOOH), cyclohexanol, and cyclohexanone has been conducted using a hybrid density functional theory method. The activation of cyclohexane and O2 is the rate-determining step in the formation of CyOOH due to its relatively high energy barrier of 41.2 kcal/mol, and the subsequent reaction behavior of CyOOH controls whether the production of cyclohexanol or cyclohexanone is favored. Using CH3COOH or (CH3COO)2Co as a catalyst reduces the energy barriers required to activate cyclohexane and O2 by 4.1 or 7.9 kcal/mol, respectively. Employing CH3COOH improves the CyOOH intramolecular dehydration process, which favors the formation of cyclohexanone. The energy barrier to the decomposition of CyOOH to CyO·, an important precursor of cyclohexanol, decreases from 35.5 kcal/mol for autoxidation to 25.9 kcal/mol for (CH3COO)2Co catalysis. (CH3COO)2Co promotes the autoxidation process via a radical chain mechanism. The computational results agree with experimental observations quite well, revealing the underlying role of CH3COOH and Co ion in cyclohexane oxidation. Graphical abstract Through DFT analysis of cyclohexane autoxidation and catalytic oxidation, we reveal the mechanism of the effects of CH3COOH and Co2+ on the reaction routes.

15.
J Colloid Interface Sci ; 517: 144-154, 2018 May 01.
Article de Anglais | MEDLINE | ID: mdl-29421674

RÉSUMÉ

A tailor-made catalyst with cobalt oxide particles encapsulated into ZSM-5 zeolites (Co3O4@HZSM-5) was prepared via a hydrothermal method with the conventional impregnated Co3O4/SiO2 catalyst as the precursor and Si source. Various characterization results show that the Co3O4@HZSM-5 catalyst has well-organized structure with Co3O4 particles compatibly encapsulated in the zeolite crystals. The Co3O4@HZSM-5 catalyst was employed as an efficient catalyst for the selective oxidation of styrene to benzaldehyde with hydrogen peroxide as a green and economic oxidant. The effect of various reaction conditions including reaction time, reaction temperature, different kinds of solvents, styrene/H2O2 molar ratio and catalyst dosage on the catalytic performance were systematically investigated. Under the optimized reaction condition, the yield of benzaldehyde can achieve 78.9% with 96.8% styrene conversion and 81.5% benzaldehyde selectivity. Such an excellent catalytic performance can be attributed to the synergistic effect between the confined reaction environment and the proper acidic property. In addition, the reaction mechanism with Co3O4@HZSM-5 as the catalyst for the selective oxidation of styrene to benzaldehyde was reasonably proposed.

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