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1.
Cell ; 184(9): 2362-2371.e9, 2021 04 29.
Article in English | MEDLINE | ID: mdl-33735608

ABSTRACT

The 501Y.V2 variants of SARS-CoV-2 containing multiple mutations in spike are now dominant in South Africa and are rapidly spreading to other countries. Here, experiments with 18 pseudotyped viruses showed that the 501Y.V2 variants do not confer increased infectivity in multiple cell types except for murine ACE2-overexpressing cells, where a substantial increase in infectivity was observed. Notably, the susceptibility of the 501Y.V2 variants to 12 of 17 neutralizing monoclonal antibodies was substantially diminished, and the neutralization ability of the sera from convalescent patients and immunized mice was also reduced for these variants. The neutralization resistance was mainly caused by E484K and N501Y mutations in the receptor-binding domain of spike. The enhanced infectivity in murine ACE2-overexpressing cells suggests the possibility of spillover of the 501Y.V2 variants to mice. Moreover, the neutralization resistance we detected for the 501Y.V2 variants suggests the potential for compromised efficacy of monoclonal antibodies and vaccines.


Subject(s)
COVID-19/immunology , COVID-19/virology , Immune Evasion , SARS-CoV-2/pathogenicity , Angiotensin-Converting Enzyme 2/metabolism , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/immunology , Antigens, Viral/immunology , Cell Line, Tumor , HEK293 Cells , Humans , Mutation/genetics , SARS-CoV-2/genetics
2.
Cell ; 182(5): 1284-1294.e9, 2020 09 03.
Article in English | MEDLINE | ID: mdl-32730807

ABSTRACT

The spike protein of SARS-CoV-2 has been undergoing mutations and is highly glycosylated. It is critically important to investigate the biological significance of these mutations. Here, we investigated 80 variants and 26 glycosylation site modifications for the infectivity and reactivity to a panel of neutralizing antibodies and sera from convalescent patients. D614G, along with several variants containing both D614G and another amino acid change, were significantly more infectious. Most variants with amino acid change at receptor binding domain were less infectious, but variants including A475V, L452R, V483A, and F490L became resistant to some neutralizing antibodies. Moreover, the majority of glycosylation deletions were less infectious, whereas deletion of both N331 and N343 glycosylation drastically reduced infectivity, revealing the importance of glycosylation for viral infectivity. Interestingly, N234Q was markedly resistant to neutralizing antibodies, whereas N165Q became more sensitive. These findings could be of value in the development of vaccine and therapeutic antibodies.


Subject(s)
Antigens, Viral/genetics , Betacoronavirus/pathogenicity , Mutation , Spike Glycoprotein, Coronavirus/genetics , A549 Cells , Animals , Antigens, Viral/immunology , Betacoronavirus/genetics , Betacoronavirus/immunology , Binding Sites , Cattle , Chlorocebus aethiops , Cricetinae , Dogs , Glycosylation , HEK293 Cells , HeLa Cells , Humans , Macaca mulatta , Madin Darby Canine Kidney Cells , Mice , RAW 264.7 Cells , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism , Swine , Vero Cells , Virulence/genetics
3.
Nat Immunol ; 23(10): 1433-1444, 2022 10.
Article in English | MEDLINE | ID: mdl-36138184

ABSTRACT

Naive T cells undergo radical changes during the transition from dormant to hyperactive states upon activation, which necessitates de novo protein production via transcription and translation. However, the mechanism whereby T cells globally promote translation remains largely unknown. Here, we show that on exit from quiescence, T cells upregulate transfer RNA (tRNA) m1A58 'writer' proteins TRMT61A and TRMT6, which confer m1A58 RNA modification on a specific subset of early expressed tRNAs. These m1A-modified early tRNAs enhance translation efficiency, enabling rapid and necessary synthesis of MYC and of a specific group of key functional proteins. The MYC protein then guides the exit of naive T cells from a quiescent state into a proliferative state and promotes rapid T cell expansion after activation. Conditional deletion of the Trmt61a gene in mouse CD4+ T cells causes MYC protein deficiency and cell cycle arrest, disrupts T cell expansion upon cognate antigen stimulation and alleviates colitis in a mouse adoptive transfer colitis model. Our study elucidates for the first time, to our knowledge, the in vivo physiological roles of tRNA-m1A58 modification in T cell-mediated pathogenesis and reveals a new mechanism of tRNA-m1A58-controlled T cell homeostasis and signal-dependent translational control of specific key proteins.


Subject(s)
Colitis , RNA, Transfer , Adoptive Transfer , Animals , Cell Proliferation/genetics , Colitis/genetics , Mice , Protein Biosynthesis , RNA, Transfer/genetics , RNA, Transfer/metabolism , T-Lymphocytes/metabolism
4.
Mol Cell ; 84(15): 2984-3000.e8, 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39002544

ABSTRACT

5-methylcytosine (m5C) is a prevalent RNA modification crucial for gene expression regulation. However, accurate and sensitive m5C sites identification remains challenging due to severe RNA degradation and reduced sequence complexity during bisulfite sequencing (BS-seq). Here, we report m5C-TAC-seq, a bisulfite-free approach combining TET-assisted m5C-to-f5C oxidation with selective chemical labeling, therefore enabling direct base-resolution m5C detection through pre-enrichment and C-to-T transitions at m5C sites. With m5C-TAC-seq, we comprehensively profiled the m5C methylomes in human and mouse cells, identifying a substantially larger number of confident m5C sites. Through perturbing potential m5C methyltransferases, we deciphered the responsible enzymes for most m5C sites, including the characterization of NSUN5's involvement in mRNA m5C deposition. Additionally, we characterized m5C dynamics during mESC differentiation. Notably, the mild reaction conditions and preservation of nucleotide composition in m5C-TAC-seq allow m5C detection in chromatin-associated RNAs. The accurate and robust m5C-TAC-seq will advance research into m5C methylation functional investigation.


Subject(s)
5-Methylcytosine , Sulfites , Transcriptome , 5-Methylcytosine/metabolism , 5-Methylcytosine/chemistry , Animals , Humans , Mice , Sulfites/chemistry , Methyltransferases/metabolism , Methyltransferases/genetics , Gene Expression Profiling/methods , Cell Differentiation
5.
Cell ; 150(3): 575-89, 2012 Aug 03.
Article in English | MEDLINE | ID: mdl-22863010

ABSTRACT

The mechanism by which cells decide to skip mitosis to become polyploid is largely undefined. Here we used a high-content image-based screen to identify small-molecule probes that induce polyploidization of megakaryocytic leukemia cells and serve as perturbagens to help understand this process. Our study implicates five networks of kinases that regulate the switch to polyploidy. Moreover, we find that dimethylfasudil (diMF, H-1152P) selectively increased polyploidization, mature cell-surface marker expression, and apoptosis of malignant megakaryocytes. An integrated target identification approach employing proteomic and shRNA screening revealed that a major target of diMF is Aurora kinase A (AURKA). We further find that MLN8237 (Alisertib), a selective inhibitor of AURKA, induced polyploidization and expression of mature megakaryocyte markers in acute megakaryocytic leukemia (AMKL) blasts and displayed potent anti-AMKL activity in vivo. Our findings provide a rationale to support clinical trials of MLN8237 and other inducers of polyploidization and differentiation in AMKL.


Subject(s)
Azepines/pharmacology , Drug Discovery , Leukemia, Megakaryoblastic, Acute/drug therapy , Megakaryocytes/metabolism , Polyploidy , Pyrimidines/pharmacology , Small Molecule Libraries , 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine/analogs & derivatives , 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine/pharmacology , Animals , Aurora Kinase A , Aurora Kinases , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Humans , Leukemia, Megakaryoblastic, Acute/genetics , Megakaryocytes/cytology , Megakaryocytes/pathology , Mice , Mice, Inbred C57BL , Protein Interaction Maps , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/metabolism , rho-Associated Kinases/metabolism
6.
Nature ; 591(7848): 147-151, 2021 03.
Article in English | MEDLINE | ID: mdl-33505025

ABSTRACT

Many sequence variants have been linked to complex human traits and diseases1, but deciphering their biological functions remains challenging, as most of them reside in noncoding DNA. Here we have systematically assessed the binding of 270 human transcription factors to 95,886 noncoding variants in the human genome using an ultra-high-throughput multiplex protein-DNA binding assay, termed single-nucleotide polymorphism evaluation by systematic evolution of ligands by exponential enrichment (SNP-SELEX). The resulting 828 million measurements of transcription factor-DNA interactions enable estimation of the relative affinity of these transcription factors to each variant in vitro and evaluation of the current methods to predict the effects of noncoding variants on transcription factor binding. We show that the position weight matrices of most transcription factors lack sufficient predictive power, whereas the support vector machine combined with the gapped k-mer representation show much improved performance, when assessed on results from independent SNP-SELEX experiments involving a new set of 61,020 sequence variants. We report highly predictive models for 94 human transcription factors and demonstrate their utility in genome-wide association studies and understanding of the molecular pathways involved in diverse human traits and diseases.


Subject(s)
Polymorphism, Single Nucleotide/genetics , SELEX Aptamer Technique , Support Vector Machine , Transcription Factors/metabolism , Binding Sites/genetics , Disease/genetics , Genome, Human/genetics , Humans , Ligands , Protein Binding
7.
Circ Res ; 135(5): 596-613, 2024 Aug 16.
Article in English | MEDLINE | ID: mdl-39056179

ABSTRACT

BACKGROUND: Macrophages are key players in obesity-associated cardiovascular diseases, which are marked by inflammatory and immune alterations. However, the pathophysiological mechanisms underlying macrophage's role in obesity-induced cardiac inflammation are incompletely understood. Our study aimed to identify the key macrophage population involved in obesity-induced cardiac dysfunction and investigate the molecular mechanism that contributes to the inflammatory response. METHODS: In this study, we used single-cell RNA-sequencing analysis of Cd45+CD11b+F4/80+ cardiac macrophages to explore the heterogeneity of cardiac macrophages. The CCR2+ (C-C chemokine receptor 2) macrophages were specifically removed by a dual recombinase approach, and the macrophage CCR2 was deleted to investigate their functions. We also performed cleavage under target and tagmentation analysis, chromatin immunoprecipitation-polymerase chain reaction, luciferase assay, and macrophage-specific lentivirus transfection to define the impact of lysozyme C in macrophages on obesity-induced inflammation. RESULTS: We find that the Ccr2 cluster undergoes a functional transition from homeostatic maintenance to proinflammation. Our data highlight specific changes in macrophage behavior during cardiac dysfunction under metabolic challenge. Consistently, inducible ablation of CCR2+CX3CR1+ macrophages or selective deletion of macrophage CCR2 prevents obesity-induced cardiac dysfunction. At the mechanistic level, we demonstrate that the obesity-induced functional shift of CCR2-expressing macrophages is mediated by the CCR2/activating transcription factor 3/lysozyme 1/NF-κB (nuclear factor kappa B) signaling. Finally, we uncover a noncanonical role for lysozyme 1 as a transcription activator, binding to the RelA promoter, driving NF-κB signaling, and strongly promoting inflammation and cardiac dysfunction in obesity. CONCLUSIONS: Our findings suggest that lysozyme 1 may represent a potential target for the diagnosis of obesity-induced inflammation and the treatment of obesity-induced heart disease.


Subject(s)
Macrophages , Muramidase , Obesity , Receptors, CCR2 , Animals , Obesity/complications , Obesity/metabolism , Macrophages/metabolism , Receptors, CCR2/metabolism , Receptors, CCR2/genetics , Mice , Muramidase/metabolism , Muramidase/genetics , Mice, Inbred C57BL , Male , Mice, Knockout , Signal Transduction , Inflammation/metabolism , Inflammation/genetics , Heart Diseases/etiology , Heart Diseases/metabolism , Heart Diseases/genetics
8.
J Virol ; 98(7): e0046724, 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-38864621

ABSTRACT

Acinetobacter baumannii, an opportunistic pathogen, poses a significant threat in intensive care units, leading to severe nosocomial infections. The rise of multi-drug-resistant strains, particularly carbapenem-resistant A. baumannii, has created formidable challenges for effective treatment. Given the prolonged development cycle and high costs associated with antibiotics, phages have garnered clinical attention as an alternative for combating infections caused by drug-resistant bacteria. However, the utilization of phage therapy encounters notable challenges, including the narrow host spectrum, where each phage targets a limited subset of bacteria, increasing the risk of phage resistance development. Additionally, uncertainties in immune system dynamics during treatment hinder tailoring symptomatic interventions based on patient-specific states. In this study, we isolated two A. baumannii phages from wastewater and conducted a comprehensive assessment of their potential applications. This evaluation included sequencing analysis, genome classification, pH and temperature stability assessments, and in vitro bacterial inhibition assays. Further investigations involved analyzing histological and cytokine alterations in rats undergoing phage cocktail treatment for pneumonia. The therapeutic efficacy of the phages was validated, and transcriptomic studies of rat lung tissue during phage treatment revealed crucial changes in the immune system. The findings from our study underscore the potential of phages for future development as a treatment strategy and offer compelling evidence regarding immune system dynamics throughout the treatment process.IMPORTANCEDue to the growing problem of multi-drug-resistant bacteria, the use of phages is being considered as an alternative to antibiotics, and the genetic safety and application stability of phages determine the potential of phage application. The absence of drug resistance genes and virulence genes in the phage genome can ensure the safety of phage application, and the fact that phage can remain active in a wide range of temperatures and pH is also necessary for application. In addition, the effect evaluation of preclinical studies is especially important for clinical application. By simulating the immune response situation during the treatment process through mammalian models, the changes in animal immunity can be observed, and the effect of phage therapy can be further evaluated. Our study provides compelling evidence that phages hold promise for further development as therapeutic agents for Acinetobacter baumannii infections.


Subject(s)
Acinetobacter Infections , Acinetobacter baumannii , Bacteriophages , Carbapenems , Disease Models, Animal , Phage Therapy , Acinetobacter baumannii/virology , Acinetobacter baumannii/drug effects , Animals , Acinetobacter Infections/therapy , Acinetobacter Infections/microbiology , Rats , Phage Therapy/methods , Carbapenems/pharmacology , Bacteriophages/physiology , Bacteriophages/genetics , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Drug Resistance, Multiple, Bacterial , Male , Genome, Viral , Wastewater , Pneumonia/therapy , Pneumonia/microbiology , Pneumonia/virology
9.
Plant Physiol ; 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39268874

ABSTRACT

In arbuscular mycorrhizal (AM) symbiosis, appropriate regulation of the formation, maintenance, and degeneration of the arbuscule are essential for plants and fungi. In this study, we identified a Cysteine-2/Histidine-2 zinc finger protein (C2H2-ZFP)-encoding gene in Lotus japonicus named Regulator of Symbiosome Differentiation-Like (LjRSDL) that is required for arbuscule degeneration. Evolutionary analysis showed that homologs of LjRSDL exist in mycorrhizal flowering plants. We obtained ProLjRSDL::GUS transgenic hairy roots and showed that LjRSDL was strongly upregulated upon AM colonization, particularly at 18 days post AM fungi inoculation and specifically expressed in arbuscular-containing cells. The mycorrhization rate increased in the ljrsdl mutant but decreased in LjRSDL overexpressed L. japonicus. Interestingly, we observed higher proportions of large arbuscule in the ljrsdl mutant but lower proportions of larger arbuscule in LjRSDL overexpressing plants. Transcriptome analyses indicated that genes involved in arbuscule degeneration were significantly changed upon the dysregulation of LjRSDL and that LjRSDL-dependent regulation in AM symbiosis is mainly via the hormone signal transduction pathway. LjRSDL, therefore, represents a C2H2-ZFP that negatively regulates AM symbiosis. Our study provides insight into understanding plant-AM fungal communication and AM symbiosis development.

10.
FASEB J ; 38(16): e23884, 2024 Aug 31.
Article in English | MEDLINE | ID: mdl-39135512

ABSTRACT

The inhibition of the autophagolysosomal pathway mediated by transcription factor EB (TFEB) inactivation in proximal tubular epithelial cells (TECs) is a key mechanism of TEC injury in diabetic kidney disease (DKD). Acetylation is a novel mechanism that regulates TFEB activity. However, there are currently no studies on whether the adjustment of the acetylation level of TFEB can reduce the damage of diabetic TECs. In this study, we investigated the effect of Trichostatin A (TSA), a typical deacetylase inhibitor, on TFEB activity and damage to TECs in both in vivo and in vitro models of DKD. Here, we show that TSA treatment can alleviate the pathological damage of glomeruli and renal tubules and delay the DKD progression in db/db mice, which is associated with the increased expression of TFEB and its downstream genes. In vitro studies further confirmed that TSA treatment can upregulate the acetylation level of TFEB, promote its nuclear translocation, and activate the expression of its downstream genes, thereby reducing the apoptosis level of TECs. TFEB deletion or HDAC6 knockdown in TECs can counteract the activation effect of TSA on autophagolysosomal pathway. We also found that TFEB enhances the transcription of Tfeb through binding to its promoter and promotes its own expression. Our results, thus, provide a novel therapeutic mechanism for DKD that the alleviation of TEC damage by activating the autophagic lysosomal pathway through upregulating TFEB acetylation can, thus, delay DKD progression.


Subject(s)
Basic Helix-Loop-Helix Leucine Zipper Transcription Factors , Diabetic Nephropathies , Epithelial Cells , Histone Deacetylase Inhibitors , Hydroxamic Acids , Kidney Tubules, Proximal , Animals , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/metabolism , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/genetics , Diabetic Nephropathies/metabolism , Mice , Acetylation , Epithelial Cells/metabolism , Epithelial Cells/drug effects , Kidney Tubules, Proximal/metabolism , Kidney Tubules, Proximal/pathology , Hydroxamic Acids/pharmacology , Histone Deacetylase Inhibitors/pharmacology , Male , Mice, Inbred C57BL , Autophagy/drug effects , Apoptosis/drug effects
11.
EMBO Rep ; 24(9): e56512, 2023 09 06.
Article in English | MEDLINE | ID: mdl-37437058

ABSTRACT

Long interspersed element 1 (LINE-1) is the only active autonomous mobile element in the human genome. Its transposition can exert deleterious effects on the structure and function of the host genome and cause sporadic genetic diseases. Tight control of LINE-1 mobilization by the host is crucial for genetic stability. In this study, we report that MOV10 recruits the main decapping enzyme DCP2 to LINE-1 RNA and forms a complex of MOV10, DCP2, and LINE-1 RNP, exhibiting liquid-liquid phase separation (LLPS) properties. DCP2 cooperates with MOV10 to decap LINE-1 RNA, which causes degradation of LINE-1 RNA and thus reduces LINE-1 retrotransposition. We here identify DCP2 as one of the key effector proteins determining LINE-1 replication, and elucidate an LLPS mechanism that facilitates the anti-LINE-1 action of MOV10 and DCP2.


Subject(s)
Cytoplasmic Granules , RNA Helicases , Humans , Cytoplasmic Granules/metabolism , Endoribonucleases/genetics , Long Interspersed Nucleotide Elements , RNA/metabolism , RNA Helicases/metabolism
12.
Exp Cell Res ; 437(1): 113998, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38513962

ABSTRACT

Plasma saturated free fatty acid (FFA)-induced endothelial dysfunction (ED) contributes to the pathogenesis of atherosclerosis and cardiovascular diseases. However, the mechanism underlying saturated FFA-induced ED remains unclear. This study demonstrated that palmitic acid (PA) induced ED by activating the NADPH oxidase (NOX)/ROS signaling pathway to activate protein phosphatase 4 (PP4) and protein phosphatase 2A (PP2A), thereby reducing endothelial nitric oxide synthase (eNOS) phosphorylation at Ser633 and Ser1177, respectively. Okadaic acid (OA) and fostriecin (FST), which are inhibitors of PP2A, inhibited the PA-induced decreases in eNOS phosphorylation at Ser633 and Ser1177. The antioxidants N-acetylcysteine (NAC) and apocynin (APO) or knockdown of gp91phox or p67phox (NOX subunits) restored PA-mediated downregulation of PP4R2 protein expression and eNOS Ser633 phosphorylation. Knockdown of the PP4 catalytic subunit (PP4c) specifically increased eNOS Ser633 phosphorylation, while silencing the PP2A catalytic subunit (PP2Ac) restored only eNOS Ser1177 phosphorylation. Furthermore, PA dramatically decreased the protein expression of the PP4 regulatory subunit R2 (PP4R2) but not the other regulatory subunits. PP4R2 overexpression increased eNOS Ser633 phosphorylation, nitric oxide (NO) production, cell migration and tube formation but did not change eNOS Ser1177 phosphorylation levels. Coimmunoprecipitation (Co-IP) suggested that PP4R2 and PP4c interacted with the PP4R3α and eNOS proteins. In summary, PA decreases PP4R2 protein expression through the Nox/ROS pathway to activate PP4, which contributes to ED by dephosphorylating eNOS at Ser633. The results of this study suggest that PP4 is a novel therapeutic target for ED and ED-associated vascular diseases.


Subject(s)
Nitric Oxide Synthase Type III , Phosphoprotein Phosphatases , Vascular Diseases , Humans , Phosphorylation , Nitric Oxide Synthase Type III/metabolism , Palmitic Acid/pharmacology , Serine/metabolism , Reactive Oxygen Species , Cells, Cultured , Protein Phosphatase 2/metabolism , Nitric Oxide/metabolism
13.
Mol Ther ; 32(7): 2340-2356, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38715363

ABSTRACT

Human papillomavirus (HPV) 16 and 18 infections are related to many human cancers. Despite several preventive vaccines for high-risk (hr) HPVs, there is still an urgent need to develop therapeutic HPV vaccines for targeting pre-existing hrHPV infections and lesions. In this study, we developed a lipid nanoparticle (LNP)-formulated mRNA-based HPV therapeutic vaccine (mHTV)-03E2, simultaneously targeting the E2/E6/E7 of both HPV16 and HPV18. mHTV-03E2 dramatically induced antigen-specific cellular immune responses, leading to significant CD8+ T cell infiltration and cytotoxicity in TC-1 tumors derived from primary lung epithelial cells of C57BL/6 mice expressing HPV E6/E7 antigens, mediated significant tumor regression, and prolonged animal survival, in a dose-dependent manner. We further demonstrated significant T cell immunity against HPV16/18 E6/E7 antigens for up to 4 months post-vaccination in immunological and distant tumor rechallenging experiments, suggesting robust memory T cell immunity against relapse. Finally, mHTV-03E2 synergized with immune checkpoint blockade to inhibit tumor growth and extend animal survival, indicating the potential in combination therapy. We conclude that mHTV-03E2 is an excellent candidate therapeutic mRNA vaccine for treating malignancies caused by HPV16 or HPV18 infections.


Subject(s)
Oncogene Proteins, Viral , Papillomavirus Infections , Papillomavirus Vaccines , RNA, Messenger , Animals , Mice , Papillomavirus Vaccines/immunology , Humans , Papillomavirus Infections/immunology , Papillomavirus Infections/virology , Papillomavirus Infections/therapy , Papillomavirus Infections/prevention & control , Female , Oncogene Proteins, Viral/immunology , Oncogene Proteins, Viral/genetics , RNA, Messenger/genetics , RNA, Messenger/immunology , Nanoparticles/chemistry , Human papillomavirus 16/immunology , Human papillomavirus 16/genetics , Mice, Inbred C57BL , Human papillomavirus 18/immunology , Human papillomavirus 18/genetics , Papillomavirus E7 Proteins/immunology , Papillomavirus E7 Proteins/genetics , Cancer Vaccines/immunology , Cancer Vaccines/administration & dosage , Cell Line, Tumor , Disease Models, Animal , CD8-Positive T-Lymphocytes/immunology , Repressor Proteins/immunology , Repressor Proteins/genetics , DNA-Binding Proteins , Liposomes
14.
Mol Cell ; 68(5): 993-1005.e9, 2017 Dec 07.
Article in English | MEDLINE | ID: mdl-29107537

ABSTRACT

Gene expression can be post-transcriptionally regulated via dynamic and reversible RNA modifications. N1-methyladenosine (m1A) is a recently identified mRNA modification; however, little is known about its precise location and biogenesis. Here, we develop a base-resolution m1A profiling method, based on m1A-induced misincorporation during reverse transcription, and report distinct classes of m1A methylome in the human transcriptome. m1A in 5' UTR, particularly those at the mRNA cap, associate with increased translation efficiency. A different, small subset of m1A exhibit a GUUCRA tRNA-like motif, are evenly distributed in the transcriptome, and are dependent on the methyltransferase TRMT6/61A. Additionally, we show that m1A is prevalent in the mitochondrial-encoded transcripts. Manipulation of m1A level via TRMT61B, a mitochondria-localizing m1A methyltransferase, demonstrates that m1A in mitochondrial mRNA interferes with translation. Collectively, our approaches reveal distinct classes of m1A methylome and provide a resource for functional studies of m1A-mediated epitranscriptomic regulation.


Subject(s)
Adenosine/analogs & derivatives , Cell Nucleus/metabolism , Mitochondria/metabolism , RNA Processing, Post-Transcriptional , RNA, Messenger/metabolism , RNA, Transfer/metabolism , Single Molecule Imaging/methods , 5' Untranslated Regions , Adenosine/metabolism , HEK293 Cells , Humans , Mitochondrial Proteins/biosynthesis , Mitochondrial Proteins/genetics , Nuclear Proteins/biosynthesis , Nuclear Proteins/genetics , Protein Biosynthesis , RNA Caps , RNA Interference , RNA, Messenger/genetics , RNA, Transfer/genetics , Transfection , tRNA Methyltransferases/genetics , tRNA Methyltransferases/metabolism
15.
Chem Soc Rev ; 53(10): 5014-5053, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38600823

ABSTRACT

Alumina materials, as one of the cornerstones of the modern chemical industry, possess physical and chemical properties that include excellent mechanical strength and structure stability, which also make them highly suitable as catalyst supports. Alumina-supported Pd-based catalysts with the advantages of exceptional catalytic performance, flexible regulated surface metal/acid sites, and good regeneration ability have been widely used in many traditional chemical industry fields and have also shown great application prospects in emerging fields. This review aims to provide an overview of the recent advances in alumina and its supported Pd-based catalysts. Specifically, the synthesis strategies, morphology transformation mechanisms, and structural properties of alumina with various morphologies are comprehensively summarized and discussed in-depth. Then, the preparation approaches of Pd/Al2O3 catalysts (impregnation, precipitation, and other emerging methods), as well as the metal-support interactions (MSIs), are revisited. Moreover, Some promising applications have been chosen as representative reactions in fine chemicals, environmental purification, and sustainable development fields to highlight the universal functionality of the alumina-supported Pd-based catalysts. The role of the Pd species, alumina support, promoters, and metal-support interactions in the enhancement of catalytic performance are also discussed. Finally, some challenges and upcoming opportunities in the academic and industrial application of the alumina and its supported Pd-based are presented and put forward.

16.
J Am Chem Soc ; 146(35): 24638-24653, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39171830

ABSTRACT

Identifying biologically active ligands for membrane proteins is an important task in chemical biology. We report an approach to directly identify small molecule agonists against membrane proteins by selecting DNA-encoded libraries (DELs) on live cells. This method connects extracellular ligand binding with intracellular biochemical transformation, thereby biasing the selection toward agonist identification. We have demonstrated the methodology with three membrane proteins: epidermal growth factor receptor (EGFR), thrombopoietin receptor (TPOR), and insulin receptor (INSR). A ∼30 million and a 1.033 billion-compound DEL were selected against these targets, and novel agonists with subnanomolar affinity and low micromolar cellular activities have been discovered. The INSR agonists activated the receptor by possibly binding to an allosteric site, exhibited clear synergistic effects with insulin, and activated the downstream signaling pathways. Notably, the agonists did not activate the insulin-like growth factor 1 receptor (IGF-1R), a highly homologous receptor whose activation may lead to tumor progression. Collectively, this work has developed an approach toward "functional" DEL selections on the cell surface and may provide a widely applicable method for agonist discovery for membrane proteins.


Subject(s)
DNA , ErbB Receptors , Receptor, Insulin , Small Molecule Libraries , Humans , Receptor, Insulin/agonists , Receptor, Insulin/metabolism , Small Molecule Libraries/pharmacology , Small Molecule Libraries/chemistry , Small Molecule Libraries/chemical synthesis , DNA/chemistry , DNA/metabolism , ErbB Receptors/metabolism , ErbB Receptors/agonists , Membrane Proteins/agonists , Membrane Proteins/metabolism , Drug Discovery , HEK293 Cells , Ligands , Antigens, CD
17.
Mol Cancer ; 23(1): 123, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38849845

ABSTRACT

BACKGROUND: Pediatric-type diffuse high-grade glioma (pHGG) is the most frequent malignant brain tumor in children and can be subclassified into multiple entities. Fusion genes activating the MET receptor tyrosine kinase often occur in infant-type hemispheric glioma (IHG) but also in other pHGG and are associated with devastating morbidity and mortality. METHODS: To identify new treatment options, we established and characterized two novel orthotopic mouse models harboring distinct MET fusions. These included an immunocompetent, murine allograft model and patient-derived orthotopic xenografts (PDOX) from a MET-fusion IHG patient who failed conventional therapy and targeted therapy with cabozantinib. With these models, we analyzed the efficacy and pharmacokinetic properties of three MET inhibitors, capmatinib, crizotinib and cabozantinib, alone or combined with radiotherapy. RESULTS: Capmatinib showed superior brain pharmacokinetic properties and greater in vitro and in vivo efficacy than cabozantinib or crizotinib in both models. The PDOX models recapitulated the poor efficacy of cabozantinib experienced by the patient. In contrast, capmatinib extended survival and induced long-term progression-free survival when combined with radiotherapy in two complementary mouse models. Capmatinib treatment increased radiation-induced DNA double-strand breaks and delayed their repair. CONCLUSIONS: We comprehensively investigated the combination of MET inhibition and radiotherapy as a novel treatment option for MET-driven pHGG. Our seminal preclinical data package includes pharmacokinetic characterization, recapitulation of clinical outcomes, coinciding results from multiple complementing in vivo studies, and insights into molecular mechanism underlying increased efficacy. Taken together, we demonstrate the groundbreaking efficacy of capmatinib and radiation as a highly promising concept for future clinical trials.


Subject(s)
Brain Neoplasms , Glioma , Proto-Oncogene Proteins c-met , Xenograft Model Antitumor Assays , Animals , Humans , Glioma/pathology , Glioma/drug therapy , Glioma/genetics , Glioma/therapy , Proto-Oncogene Proteins c-met/antagonists & inhibitors , Proto-Oncogene Proteins c-met/genetics , Proto-Oncogene Proteins c-met/metabolism , Mice , Brain Neoplasms/pathology , Brain Neoplasms/drug therapy , Brain Neoplasms/genetics , Brain Neoplasms/radiotherapy , Benzamides/pharmacology , Benzamides/therapeutic use , Cell Line, Tumor , Oncogene Proteins, Fusion/genetics , Oncogene Proteins, Fusion/metabolism , Female , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , Pyridines/pharmacology , Pyridines/therapeutic use , Crizotinib/pharmacology , Crizotinib/therapeutic use , Disease Models, Animal , Child , Neoplasm Grading , Anilides/pharmacology , Imidazoles , Triazines
18.
Apoptosis ; 29(3-4): 289-302, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38095762

ABSTRACT

Metal ions play an important role in living organisms and are involved in essential physiological activities. However, the overload state of ions can cause excess free radicals, cell damage, and even cell death. Ferroptosis and cuproptosis are specific forms of cell death that are distinct from apoptosis, necroptosis, and other regulated cell death. These unique modalities of cell death, dependent on iron and copper, are regulated by multiple cellular metabolic pathways, including steady-state metal redox treatment mitochondrial activity of lipid, amino acid and glucose metabolism, and various signaling pathways associated with disease. Although the mechanisms of ferroptosis and cuproptosis are not yet fully understood, there is no doubt that ion overload plays a crucial act in these metal-dependent cell deaths. In this review, we discussed the core roles of ion overload in ferroptosis and cuproptosis, the association between metabolism imbalance and ferroptosis and cuproptosis, the extract the diseases caused by ion overload and current treatment modalities.


Subject(s)
Ferroptosis , Kidney Diseases , Regulated Cell Death , Humans , Ferroptosis/genetics , Apoptosis , Ions
19.
Apoptosis ; 29(1-2): 169-190, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37713112

ABSTRACT

Cuprotosis, an emerging mode of cell death, has recently caught the attention of researchers worldwide. However, its impact on low-grade glioma (LGG) patients has not been fully explored. To gain a deeper insight into the relationship between cuprotosis and LGG patients' prognosis, we conducted this study in which LGG patients were divided into two clusters based on the expression of 18 cuprotosis-related genes. We found that LGG patients in cluster A had better prognosis than those in cluster B. The two clusters also differed in terms of immune cell infiltration and biological functions. Moreover, we identified differentially expressed genes (DEGs) between the two clusters and developed a cuprotosis-related prognostic signature through the least absolute shrinkage and selection operator (LASSO) analysis in the TCGA training cohort. This signature divided LGG patients into high- and low-risk groups, with the high-risk group having significantly shorter overall survival (OS) time than the low-risk group. Its predictive reliability for prognosis in LGG patients was confirmed by the TCGA internal validation cohort, CGGA325 cohort and CGGA693 cohort. Additionally, a nomogram was used to predict the 1-, 3-, and 5-year OS rates of each patient. The analysis of immune checkpoints and tumor mutation burden (TMB) has revealed that individuals belonging to high-risk groups have a greater chance of benefiting from immunotherapy. Functional experiments confirmed that interfering with the signature gene TNFRSF11B inhibited LGG cell proliferation and migration. Overall, this study shed light on the importance of cuprotosis in LGG patient prognosis. The cuprotosis-related prognostic signature is a reliable predictor for patient outcomes and immunotherapeutic response and can help to develop new therapies for LGG.


Subject(s)
Apoptosis , Glioma , Humans , Reproducibility of Results , Cell Death , Glioma/genetics , Glioma/therapy , Immunotherapy
20.
Anal Chem ; 96(1): 309-316, 2024 01 09.
Article in English | MEDLINE | ID: mdl-38108827

ABSTRACT

The separation and analysis of circulating tumor cells (CTCs) in liquid biopsy significantly facilitated clinical cancer diagnosis and personalized therapy. However, current methods face challenges in simultaneous efficient capturing, separation, and imaging of CTCs, and most of the devices cannot be reused/regenerated. We present here an innovative glowing octopus-inspired nanomachine (GOIN), capable of capturing, imaging, separating, and controlling the release of cancer cells from whole blood and normal cells. The GOIN comprises an aptamer-decorated magnetic fluorescent covalent organic framework (COF), which exhibits a strong affinity for nucleolin-overexpressed cancer cells through a multivalent binding effect. The captured cancer cells can be directly imaged using the intrinsic stable fluorescence of the COF layer in the GOIN. Employing magnet and NIR laser assistance enables easy separation and mild photothermal release of CTCs from the normal cells and the nanomachine without compromising cell viability. Moreover, the GOIN demonstrates a reusing capability, as the NIR-triggered CTC release is mild and nondestructive, allowing the GOIN to be reused at least three times.


Subject(s)
Neoplastic Cells, Circulating , Humans , Cell Separation/methods , Neoplastic Cells, Circulating/pathology , Cell Line, Tumor , Diagnostic Imaging , Cell Survival
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