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1.
Cell Commun Signal ; 22(1): 234, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643181

RESUMO

BACKGROUND: p66Shc, as a redox enzyme, regulates reactive oxygen species (ROS) production in mitochondria and autophagy. However, the mechanisms by which p66Shc affects autophagosome formation are not fully understood. METHODS: p66Shc expression and its location in the trophoblast cells were detected in vivo and in vitro. Small hairpin RNAs or CRISPR/Cas9, RNA sequencing, and confocal laser scanning microscope were used to clarify p66Shc's role in regulating autophagic flux and STING activation. In addition, p66Shc affects mitochondrial-associated endoplasmic reticulum membranes (MAMs) formation were observed by transmission electron microscopy (TEM). Mitochondrial function was evaluated by detected cytoplastic mitochondrial DNA (mtDNA) and mitochondrial membrane potential (MMP). RESULTS: High glucose induces the expression and mitochondrial translocation of p66Shc, which promotes MAMs formation and stimulates PINK1-PRKN-mediated mitophagy. Moreover, mitochondrial localized p66Shc reduces MMP and triggers cytosolic mtDNA release, thus activates cGAS/STING signaling and ultimately leads to enhanced autophagy and cellular senescence. Specially, we found p66Shc is required for the interaction between STING and LC3II, as well as between STING and ATG5, thereby regulates cGAS/STING-mediated autophagy. We also identified hundreds of genes associated several biological processes including aging are co-regulated by p66Shc and ATG5, deletion either of which results in diminished cellular senescence. CONCLUSION: p66Shc is not only implicated in the initiation of autophagy by promoting MAMs formation, but also helps stabilizing active autophagic flux by activating cGAS/STING pathway in trophoblast.


Assuntos
Autofagossomos , Trofoblastos Extravilosos , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/metabolismo , Autofagossomos/metabolismo , Autofagia , DNA Mitocondrial/metabolismo , Trofoblastos/metabolismo , Glucose/metabolismo , Nucleotidiltransferases/metabolismo
2.
BMC Biol ; 22(1): 101, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38685010

RESUMO

BACKGROUND: CRISPR-Cas9 genome editing often induces unintended, large genomic rearrangements, posing potential safety risks. However, there are no methods for mitigating these risks. RESULTS: Using long-read individual-molecule sequencing (IDMseq), we found the microhomology-mediated end joining (MMEJ) DNA repair pathway plays a predominant role in Cas9-induced large deletions (LDs). We targeted MMEJ-associated genes genetically and/or pharmacologically and analyzed Cas9-induced LDs at multiple gene loci using flow cytometry and long-read sequencing. Reducing POLQ levels or activity significantly decreases LDs, while depleting or overexpressing RPA increases or reduces LD frequency, respectively. Interestingly, small-molecule inhibition of POLQ and delivery of recombinant RPA proteins also dramatically promote homology-directed repair (HDR) at multiple disease-relevant gene loci in human pluripotent stem cells and hematopoietic progenitor cells. CONCLUSIONS: Our findings reveal the contrasting roles of RPA and POLQ in Cas9-induced LD and HDR, suggesting new strategies for safer and more precise genome editing.


Assuntos
Sistemas CRISPR-Cas , Reparo do DNA por Junção de Extremidades , Edição de Genes , Humanos , Edição de Genes/métodos , Quebras de DNA , Reparo de DNA por Recombinação , Deleção de Sequência , DNA Polimerase teta , Proteína de Replicação A/metabolismo , Proteína de Replicação A/genética
3.
Mol Ther Nucleic Acids ; 35(1): 102149, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38435118

RESUMO

Patients with pre-existing medical conditions are at a heightened risk of contracting severe acute respiratory syndrome (SARS), SARS-CoV-2, and influenza viruses, which can result in more severe disease progression and increased mortality rates. Nevertheless, the molecular mechanism behind this phenomenon remained largely unidentified. Here, we found that microRNA-19a/b (miR-19a/b), which is a constituent of the miR-17-92 cluster, exhibits reduced expression levels in patients with coronary heart disease in comparison to healthy individuals. The downregulation of miR-19a/b has been observed to facilitate the replication of influenza A virus (IAV). miR-19a/b can effectively inhibit IAV replication by targeting and reducing the expression of SOCS1, as observed in cell-based and coronary heart disease mouse models. This mechanism leads to the alleviation of the inhibitory effect of SOCS1 on the interferon (IFN)/JAK/STAT signaling pathway. The results indicate that the IAV employs a unique approach to inhibit the host's type I IFN-mediated antiviral immune responses by decreasing miR-19a/b. These findings provide additional insights into the underlying mechanisms of susceptibility to flu in patients with coronary heart disease. miR-19a/b can be considered as a preventative/therapy strategy for patients with coronary heart disease against influenza virus infection.

4.
Virology ; 593: 110031, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38401339

RESUMO

Enteromorpha polysaccharides (EPPs) have been reported to have antiviral and anti-inflammatory properties. To explore the effect of EPPs on H5N1-infected mice, mice were pretreated with EPPs before being infected with the H5N1 influenza virus intranasally. H5N1 infection resulted in body-weight loss, pulmonary and intestinal damage, and an imbalance of gut microbiota in mice. As a result of the inclusion of EPPs, the body weight of mice recovered and pathological damage to the lung and intestine was reduced. EPPs also diminished inflammation by drastically lowering the expression of proinflammatory cytokines in lungs and intestines. H5N1 infection reduced bacterial diversity, and the abundance of pathogenic bacteria such as Desulfovibrio increased. However, the beneficial bacteria Alistipes rebounded in the groups which received EPPs before the infection. The modulation of the gut-lung axis may be related to the mechanism of EPPs in antiviral and anti-inflammatory responses. EPPs have shown potential in protecting the host from the influenza A virus infection.


Assuntos
Virus da Influenza A Subtipo H5N1 , Influenza Humana , Infecções por Orthomyxoviridae , Animais , Camundongos , Humanos , Virus da Influenza A Subtipo H5N1/metabolismo , Pulmão/patologia , Citocinas/genética , Citocinas/metabolismo , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologia , Polissacarídeos/metabolismo , Antivirais/farmacologia , Antivirais/metabolismo , Camundongos Endogâmicos BALB C
5.
ACS Omega ; 9(1): 486-493, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38222535

RESUMO

The formation of C-Br(s) is one of the most fundamental reactions in organic synthesis. Oxidative bromination is a "green" way to achieve it. Aerobic bromination has drawn great interest in the past decades, while the poor substrate scope and selectivity, low efficiency, and the use of metal catalyst still confine its application. In this article, we establish a transition-metal-free aerobic bromination promoted by ionic liquid in a catalytic amount with controllable chemoselectivity toward numbers of C-Br(s) formed, and both NaBr/AcOH and HBr(aq) could be used as the bromine source. This methodology shows high efficiency and has a broad substrate scope for various kinds of C-H(s). We also validate this system by the gram-scale (one-pot) synthesis of functional molecules and direct recycle of the catalyst. The possible radical pathway of this catalysis is also presented with evidence.

6.
JAMA Ophthalmol ; 142(1): 25-32, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38060235

RESUMO

Importance: Visual impairment in working-age individuals can affect their general health and employment prospects, leading to decreased social and economic productivity and increased poverty rates. Nonetheless, investigations in this population appear to be limited. Objective: To investigate the trends of visual impairment prevalence and disability-adjusted life-years (DALYs) in working-age individuals from 1990 to 2019. Design, Setting, and Participants: This cross-sectional, population-based study used data for individuals of working age (15-64 years) from 204 countries and territories obtained from the Global Burden of Disease 2019 study. The data analysis was performed between May 1 and 10, 2023. Exposure: Visual impairment, defined as visual acuity of less than 6/18 (20/60) or near visual acuity of less than 6/12 (20/40) distance equivalent as determined by Snellen chart. Main Outcomes and Measures: Trends of visual impairment prevalence, DALYs, and corresponding estimated annual percent changes (EAPCs) from 1990 to 2019 were stratified according to region, nation, and sociodemographic index (SDI). Results: There were 437 539 484 (95% uncertainty interval [UI], 325 463 851-575 573 588) prevalent cases of visual impairment globally (53.12% female and 46.88% male) in 2019, representing an increase of 91.46% from 1990 (prevalent cases, 228 530 964; 95% UI, 172 515 833-297 118 596). Over 3 decades, visual impairment-associated DALYs increased from 7 601 852 (95% UI, 5 047 030-11 107 897) to 12 563 276 (95% UI, 8 278 866-18 961 723). Among the 5 SDI groups, the low-SDI group had the largest increase in DALYs (898 167 [95% UI, 597 161-1 301 931] in 1990 to 1 634 122 [95% UI, 1 079 102-2 444 381] in 2019). Regionally, the greatest increase in prevalence was observed in Eastern Europe (EAPC, 0.10; 95% CI, 0.02-0.19). Among all countries and territories, Nepal had the highest national prevalence of visual impairment per 100 000 population in 2019 (26 008.45; 95% UI, 19 987.35-32 482.09), while South Sudan had the highest DALY rate per 100 000 population (480.59; 95% UI, 316.06-697.06). Conclusions and Relevance: Despite the mild decrease in visual impairment prevalence rates in less-developed countries, these findings suggest that the number of prevalent cases globally has increased substantially, with discernible unfavorable patterns in developed regions. The findings support the notion that visual impairment in working-age individuals is a growing global health challenge. A better understanding of its epidemiology may facilitate the development of appropriate measures for prevention and treatment from both medical and social perspectives.


Assuntos
Carga Global da Doença , Saúde Global , Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Anos de Vida Ajustados por Qualidade de Vida , Estudos Transversais , Prevalência , Transtornos da Visão/epidemiologia , Incidência
7.
Psychol Res Behav Manag ; 16: 4515-4527, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37942439

RESUMO

Purpose: This paper aims to redefine happiness goals and explore the conditions and mechanisms through which these redefined happiness goals influence work-related outcomes. Methods: The study developed and validated scales for self-focused happiness and other-focused happiness through exploratory factor analyses of 244 employees and confirmatory factor analyses of 300 employees. The proposed theoretical model was subsequently tested using a time-lagged analysis with data from 556 supervisor-employee dyads. Results: The findings provide strong evidence for the categorization of happiness goals into self-focused happiness and other-focused happiness. Furthermore, both self-focused and other-focused happiness significantly contribute to work-related vigor, subsequently influencing employee creativity. Additionally, the impact of these happiness goals on vigor and creativity is contingent upon the availability of job resources. Conclusion: This study highlights the substantial role of self-focused and other-focused happiness in enhancing employee vigor and creativity. However, the extent of these effects depends on the level of available job resources. These outcomes carry notable implications for the fields of positive psychology, positive organizational behavior, and creativity.

8.
Proc Natl Acad Sci U S A ; 120(47): e2309227120, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37963245

RESUMO

Spatial transcriptomics technology has revolutionized our understanding of cell types and tissue organization, opening possibilities for researchers to explore transcript distributions at subcellular levels. However, existing methods have limitations in resolution, sensitivity, or speed. To overcome these challenges, we introduce SPRINTseq (Spatially Resolved and signal-diluted Next-generation Targeted sequencing), an innovative in situ sequencing strategy that combines hybrid block coding and molecular dilution strategies. Our method enables fast and sensitive high-resolution data acquisition, as demonstrated by recovering over 142 million transcripts using a 108-gene panel from 453,843 cells from four mouse brain coronal slices in less than 2 d. Using this advanced technology, we uncover the cellular and subcellular molecular architecture of Alzheimer's disease, providing additional information into abnormal cellular behaviors and their subcellular mRNA distribution. This improved spatial transcriptomics technology holds great promise for exploring complex biological processes and disease mechanisms.


Assuntos
Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Animais , Camundongos , RNA Mensageiro/genética , Transcriptoma
9.
Natl Sci Rev ; 10(9): nwad161, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37936830

RESUMO

The ongoing COVID-19 pandemic caused by SARS-CoV-2 has raised global concern for public health and economy. The development of therapeutics and vaccines to combat this virus is continuously progressing. Multi-omics approaches, including genomics, transcriptomics, proteomics, metabolomics, epigenomics and metallomics, have helped understand the structural and molecular features of the virus, thereby assisting in the design of potential therapeutics and accelerating vaccine development for COVID-19. Here, we provide an up-to-date overview of the latest applications of multi-omics technologies in strategies addressing COVID-19, in order to provide suggestions towards the development of highly effective knowledge-based therapeutics and vaccines.

10.
Biofabrication ; 15(4)2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37552975

RESUMO

Organoid technology offers sophisticatedin vitrohuman models for basic research and drug development. However, low batch-to-batch reproducibility and high cost due to laborious procedures and materials prevent organoid culture standardization for automation and high-throughput applications. Here, using a novel platform based on the findings that Pluronic F-127 (PF-127) could trigger highly uniform spheroid assembly through a mechanism different from plate coating, we develop a one-pot organoid differentiation strategy. Using our strategy, we successfully generate cortical, nephron, hepatic, and lung organoids with improved reproducibility compared to previous methods while reducing the original costs by 80%-95%. In addition, we adapt our platform to microfluidic chips allowing automated culture. We showcase that our platform can be applied to tissue-specific screening, such as drug toxicity and transfection reagents testing. Finally, we generateNEAT1knockout tissue-specific organoids and showNEAT1modulates multiple signaling pathways fine-tuning the differentiation of nephron and hepatic organoids and suppresses immune responses in cortical organoids. In summary, our strategy provides a powerful platform for advancing organoid research and studying human development and diseases.


Assuntos
Organoides , Poloxâmero , Humanos , Poloxâmero/farmacologia , Reprodutibilidade dos Testes , Análise Custo-Benefício , Fígado
11.
Nutrients ; 15(15)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37571299

RESUMO

The impact of lactoferrin, an antimicrobial peptide (AMP) with iron-binding properties, on the intestinal barrier and microflora of mice infected with highly pathogenic avian influenza A (H5N1) virus remains unclear. To investigate the effects of lactoferrin on the histopathology and intestinal microecological environment, we conducted a study using H5N1-infected mice. H5N1 infection resulted in pulmonary and intestinal damage, as well as an imbalance in gut microbiota, significantly increasing the abundance of pathogenic bacteria such as Helicobacter pylori and Campylobacter. The consumption of lactoferrin in the diet alleviated lung injury and restored the downregulation of the INAVA gene and intestinal dysfunction caused by H5N1 infection. Lactoferrin not only reduced lung and intestinal injury, but also alleviated inflammation and reversed the changes in intestinal microflora composition while increasing the abundance of beneficial bacteria. Moreover, lactoferrin rebalanced the gut microbiota and partially restored intestinal homeostasis. This study demonstrated that lactoferrin exerts its effects on the intestinal tract, leading to improvements in gut microbiota and restoration of the integrity of both the intestinal wall and lung tissue. These findings support the notion that lactoferrin may be a promising candidate for systemic treatment of influenza by locally acting on the intestine and microbiota.


Assuntos
Microbioma Gastrointestinal , Virus da Influenza A Subtipo H5N1 , Enteropatias , Animais , Camundongos , Lactoferrina/farmacologia , Virus da Influenza A Subtipo H5N1/fisiologia , Inflamação/tratamento farmacológico , Inflamação/patologia , Intestinos/microbiologia , Bactérias/genética , Enteropatias/patologia
12.
Nat Ecol Evol ; 7(11): 1914-1929, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37652999

RESUMO

The tiger (Panthera tigris) is a charismatic megafauna species that originated and diversified in Asia and probably experienced population contraction and expansion during the Pleistocene, resulting in low genetic diversity of modern tigers. However, little is known about patterns of genomic diversity in ancient populations. Here we generated whole-genome sequences from ancient or historical (100-10,000 yr old) specimens collected across mainland Asia, including a 10,600-yr-old Russian Far East specimen (RUSA21, 8× coverage) plus six ancient mitogenomes, 14 South China tigers (0.1-12×) and three Caspian tigers (4-8×). Admixture analysis showed that RUSA21 clustered within modern Northeast Asian phylogroups and partially derived from an extinct Late Pleistocene lineage. While some of the 8,000-10,000-yr-old Russian Far East mitogenomes are basal to all tigers, one 2,000-yr-old specimen resembles present Amur tigers. Phylogenomic analyses suggested that the Caspian tiger probably dispersed from an ancestral Northeast Asian population and experienced gene flow from southern Bengal tigers. Lastly, genome-wide monophyly supported the South China tiger as a distinct subspecies, albeit with mitochondrial paraphyly, hence resolving its longstanding taxonomic controversy. The distribution of mitochondrial haplogroups corroborated by biogeographical modelling suggested that Southwest China was a Late Pleistocene refugium for a relic basal lineage. As suitable habitat returned, admixture between divergent lineages of South China tigers took place in Eastern China, promoting the evolution of other northern subspecies. Altogether, our analysis of ancient genomes sheds light on the evolutionary history of tigers and supports the existence of nine modern subspecies.


Assuntos
Tigres , Animais , Tigres/genética , DNA Antigo , Filogenia , Federação Russa , China
13.
Genome Res ; 33(8): 1354-1368, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37491077

RESUMO

The interactome networks at the DNA, RNA, and protein levels are crucial for cellular functions, and the diverse variations of these networks are heavily involved in the establishment of different cell states. We have developed a diffusion-based method, Hi-C to geometry (CTG), to obtain reliable geometric information on the chromatin from Hi-C data. CTG produces a consistent and reproducible framework for the 3D genomic structure and provides a reliable and quantitative understanding of the alterations of genomic structures under different cellular conditions. The genomic structure yielded by CTG serves as an architectural blueprint of the dynamic gene regulatory network, based on which cell-specific correspondence between gene-gene and corresponding protein-protein physical interactions, as well as transcription correlation, is revealed. We also find that gene fusion events are significantly enriched between genes of short CTG distances and are thus close in 3D space. These findings indicate that 3D chromatin structure is at least partially correlated with downstream processes such as transcription, gene regulation, and even regulatory networking through affecting protein-protein interactions.


Assuntos
Cromatina , Redes Reguladoras de Genes , Cromatina/genética , Regulação da Expressão Gênica , Cromossomos , DNA
14.
Methods Mol Biol ; 2689: 107-118, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37430050

RESUMO

In mammals, it is believed that the intercellular coupling mechanism between neurons in the suprachiasmatic nucleus (SCN) confers circadian robustness and distinguishes the central clock from peripheral circadian oscillators. Current in vitro culturing methods mainly work with Petri dishes to study intercellular coupling by exogenous factors and invariably cause perturbations, such as simple exchanges of media. Here, a microfluidic device is designed to quantitatively study the intercellular coupling mechanism of circadian clock at the single-cell level and to demonstrate that the vasoactive intestinal peptide (VIP)-induced coupling in clock mutant Cry1-/- mouse adult fibroblasts (MAF), which are engineered to express the VIP receptor (i.e., VPAC2), is sufficient to synchronize, and maintain, robust circadian oscillations. This method provides a proof-of-concept strategy to reconstitute the intercellular coupling system of the central clock using uncoupled, single mouse adult fibroblast (MAF) cells in vitro and to mimic SCN slice cultures ex vivo and mouse behavior in vivo phenotypically. Such a versatile microfluidic platform may greatly facilitate the studies of intercellular regulation networks and provide new insights into the coupling mechanisms of the circadian clock.


Assuntos
Relógios Circadianos , Animais , Camundongos , Microfluídica , Dispositivos Lab-On-A-Chip , Neurônios , Núcleo Supraquiasmático , Mamíferos
15.
Light Sci Appl ; 12(1): 170, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37419880

RESUMO

White organic light-emitting diodes (WOLEDs) is a new generation of lighting technology and has stimulated wide-ranging studies. Despite the advantage of simple device structure, single-emitting-layer WOLEDs (SEL-WOLEDs) still face the challenges of difficult material screening and fine energy level regulation. Herein, we report efficient SEL-WOLEDs with a sky-blue emitting cerium(III) complex Ce-TBO2Et and an orange-red emitting europium(II) complex Eu(Tp2Et)2 as the emitters, showing a maximum external quantum efficiency of 15.9% and Commission Internationale de l'Eclairage coordinates of (0.33, 0.39) at various luminances. Most importantly, the electroluminescence mechanism of direct hole capture and hindered energy transfer between the two emitters facilitate a manageable weight doping concentration of 5% for Eu(Tp2Et)2, avoiding the low concentration (<1%) of the low-energy emitter in typical SEL-WOLEDs. Our results indicate that d-f transition emitters may circumvent fine energy level regulation and provide development potential for SEL-WOLEDs.

16.
Virus Genes ; 59(4): 604-612, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37266848

RESUMO

H11N9 viruses in wild birds might have provided the NA gene of human H7N9 virus in early 2013 in China, which evolved with highly pathogenic strains in 2017 and caused severe fatalities. To investigate the prevalence and evolution of the H11N9 influenza viruses, 16,781 samples were collected and analyzed during 2016-2020. As a result, a novel strain of influenza A (H11N9) virus with several characteristics that increase virulence was isolated. This strain had reduced pathogenicity in chicken and mice and was able to replicate in mice without prior adaptation. Phylogenetic analyses showed that it was a sextuple-reassortant virus of H11N9, H3N8, H3N6, H7N9, H9N2, and H6N8 viruses present in China, similar to the H11N9 strains in Japan and Korea during the same period. This was the H11N9 strain isolated from China most recently, which add a record to viruses in wild birds. This study identified a new H11N9 reassortant in a wild bird with key mutation contributing to virulence. Therefore, comprehensive surveillance and enhanced biosecurity precautions are particularly important for the prediction and prevention of potential pandemics resulting from reassortant viruses with continuous evolution and expanding geographic distributions.


Assuntos
Vírus da Influenza A Subtipo H3N8 , Subtipo H7N9 do Vírus da Influenza A , Vírus da Influenza A Subtipo H9N2 , Influenza Aviária , Animais , Camundongos , Humanos , Patos , Subtipo H7N9 do Vírus da Influenza A/genética , Vírus da Influenza A Subtipo H9N2/genética , Filogenia , Animais Selvagens , Galinhas , Vírus Reordenados/genética
17.
Aging (Albany NY) ; 15(9): 3644-3677, 2023 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-37155154

RESUMO

Cancers originate from a single cell according to Nowell's theory of clonal evolution. The enrichment of the most aggressive clones has been developed and the heterogeneity arises for genomic instability and environmental selection. Multiple myeloma (MM) is a multiple relapse plasma cell cancer generated from bone marrow. Although there were accumulating researches in multiple myeloma pathogenesis, the heterogeneity remains poorly understood. The participants enrolled in this study were 4 EMP+ (EMP, Extramedullary plasmacytoma) and 2 EMP- primarily untreated MM patients. Single cell RNA sequencing and analysis were conducted for the single cell suspension, which was sorted by flow cytometry from peripheral blood mononuclear cells or bone marrow cells. In our research, the results of single cell RNA sequencing show that FAM46C determines MM tumor heterogeneity predicting extramedullary metastasis by influencing RNA stability. Further, we integrated and analyzed 2280 multiple myeloma samples from 7 independent datasets, which uncover that FAM46C mediated tumor heterogeneity predicts poorer survival in multiple myeloma.


Assuntos
Mieloma Múltiplo , Plasmocitoma , Humanos , Medula Óssea/patologia , Leucócitos Mononucleares , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Recidiva Local de Neoplasia , Plasmocitoma/patologia
18.
J Phys Chem B ; 127(18): 4145-4153, 2023 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-37130439

RESUMO

There is growing evidence showing that many critical biological processes are driven by biomolecule condensates through liquid-liquid phase separation (LLPS). Although the qualitative observation and description of LLPS have been well documented, quantitative simulations of the time-dependent progression of LLPS in live cells are generally lacking. In this work, we build a stochastic Monte Carlo model to simulate the dynamic LLPS process during the formation of bacterial aggresomes. We demonstrate that the size distribution of the protein condensates evolves from an exponential-like to a bimodal-like pattern, and the number of condensates increases at the beginning and then decreases after reaching a maximum. Incorporating diffusion and collision, our simplified model recapitulates the two-step LLPS process in which many smaller condensates are formed in the first step and then merged into a few larger ones. We further reveal that the condensation speed, which can be defined by the condensates formed in unit time during the first step, is mainly determined by both the collision energy barrier and the initial protein density, while the number of condensates at the equilibrium is mainly associated with the dissociation energy barrier. Moreover, the LLPS process is not sensitive to temperature changes ranging around physiological conditions. Additionally, we consider the effect of the nucleation energy barrier on LLPS. We find that a higher nucleation energy barrier brings a slower condensation speed. Overall, we simulate the spatiotemporal dynamics of the LLPS process and provide qualitative guidance for understanding the dynamics of LLPS in bacterial cells, which can faithfully recapitulate experimental observations and facilitate the design of future experimental tests.


Assuntos
Bactérias , Proteínas , Bactérias/citologia
19.
Biomed Opt Express ; 14(4): 1659-1669, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37078040

RESUMO

Light sheet microscopy combined with a microchip is an emerging tool in biomedical research that notably improves efficiency. However, microchip-enhanced light-sheet microscopy is limited by noticeable aberrations induced by the complex refractive indices in the chip. Herein, we report a droplet microchip that is specifically engineered to be capable of large-scale culture of 3D spheroids (over 600 samples per chip) and has a polymer index matched to water (difference <1%). When combined with a lab-built open-top light-sheet microscope, this microchip-enhanced microscopy technique allows 3D time-lapse imaging of the cultivated spheroids with ∼2.5-µm single-cell resolution and a high throughput of ∼120 spheroids per minute. This technique was validated by a comparative study on the proliferation and apoptosis rates of hundreds of spheroids with or without treatment with the apoptosis-inducing drug Staurosporine.

20.
Nucleic Acids Res ; 51(8): 3793-3805, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37014011

RESUMO

Maternal mitochondria are the sole source of mtDNA for every cell of the offspring. Heteroplasmic mtDNA mutations inherited from the oocyte are a common cause of metabolic diseases and associated with late-onset diseases. However, the origin and dynamics of mtDNA heteroplasmy remain unclear. We used our individual Mitochondrial Genome sequencing (iMiGseq) technology to study mtDNA heterogeneity, quantitate single nucleotide variants (SNVs) and large structural variants (SVs), track heteroplasmy dynamics, and analyze genetic linkage between variants at the individual mtDNA molecule level in single oocytes and human blastoids. Our study presented the first single-mtDNA analysis of the comprehensive heteroplasmy landscape in single human oocytes. Unappreciated levels of rare heteroplasmic variants well below the detection limit of conventional methods were identified in healthy human oocytes, of which many are reported to be deleterious and associated with mitochondrial disease and cancer. Quantitative genetic linkage analysis revealed dramatic shifts of variant frequency and clonal expansions of large SVs during oogenesis in single-donor oocytes. iMiGseq of a single human blastoid suggested stable heteroplasmy levels during early lineage differentiation of naïve pluripotent stem cells. Therefore, our data provided new insights of mtDNA genetics and laid a foundation for understanding mtDNA heteroplasmy at early stages of life.


Assuntos
DNA Mitocondrial , Células-Tronco Pluripotentes , Humanos , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Haplótipos , Heteroplasmia , Mitocôndrias/genética , Mitocôndrias/metabolismo , Oócitos/metabolismo , Células-Tronco Pluripotentes/metabolismo
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