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1.
Cell ; 185(18): 3341-3355.e13, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35998629

RESUMO

The extracellular pH is a vital regulator of various biological processes in plants. However, how plants perceive extracellular pH remains obscure. Here, we report that plant cell-surface peptide-receptor complexes can function as extracellular pH sensors. We found that pattern-triggered immunity (PTI) dramatically alkalinizes the acidic extracellular pH in root apical meristem (RAM) region, which is essential for root meristem growth factor 1 (RGF1)-mediated RAM growth. The extracellular alkalinization progressively inhibits the acidic-dependent interaction between RGF1 and its receptors (RGFRs) through the pH sensor sulfotyrosine. Conversely, extracellular alkalinization promotes the alkaline-dependent binding of plant elicitor peptides (Peps) to its receptors (PEPRs) through the pH sensor Glu/Asp, thereby promoting immunity. A domain swap between RGFR and PEPR switches the pH dependency of RAM growth. Thus, our results reveal a mechanism of extracellular pH sensing by plant peptide-receptor complexes and provide insights into the extracellular pH-mediated regulation of growth and immunity in the RAM.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Concentração de Íons de Hidrogênio , Meristema/metabolismo , Peptídeos/metabolismo , Células Vegetais , Raízes de Plantas/metabolismo , Plantas/metabolismo , Receptores de Superfície Celular/metabolismo , Transdução de Sinais
2.
Cell ; 182(5): 1109-1124.e25, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32841601

RESUMO

Chloroplasts are crucial players in the activation of defensive hormonal responses during plant-pathogen interactions. Here, we show that a plant virus-encoded protein re-localizes from the plasma membrane to chloroplasts upon activation of plant defense, interfering with the chloroplast-dependent anti-viral salicylic acid (SA) biosynthesis. Strikingly, we have found that plant pathogens from different kingdoms seem to have convergently evolved to target chloroplasts and impair SA-dependent defenses following an association with membranes, which relies on the co-existence of two subcellular targeting signals, an N-myristoylation site and a chloroplast transit peptide. This pattern is also present in plant proteins, at least one of which conversely activates SA defenses from the chloroplast. Taken together, our results suggest that a pathway linking plasma membrane to chloroplasts and activating defense exists in plants and that such pathway has been co-opted by plant pathogens during host-pathogen co-evolution to promote virulence through suppression of SA responses.


Assuntos
Membrana Celular/imunologia , Cloroplastos/imunologia , Doenças das Plantas/imunologia , Imunidade Vegetal/imunologia , Transdução de Sinais/imunologia , Proteínas de Arabidopsis/imunologia , Interações Hospedeiro-Patógeno/imunologia , Ácido Salicílico/imunologia , Virulência/imunologia
3.
Mol Cell ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39096898

RESUMO

The IscB proteins, as the ancestors of Cas9 endonuclease, hold great promise due to their small size and potential for diverse genome editing. However, their activity in mammalian cells is unsatisfactory. By introducing three residual substitutions in IscB, we observed an average 7.5-fold increase in activity. Through fusing a sequence-non-specific DNA-binding protein domain, the eIscB-D variant achieved higher editing efficiency, with a maximum of 91.3%. Moreover, engineered ωRNA was generated with a 20% reduction in length and slightly increased efficiency. The engineered eIscB-D/eωRNA system showed an average 20.2-fold increase in activity compared with the original IscB. Furthermore, we successfully adapted eIscB-D for highly efficient cytosine and adenine base editing. Notably, eIscB-D is highly active in mouse cell lines and embryos, enabling the efficient generation of disease models through mRNA/ωRNA injection. Our study suggests that these miniature genome-editing tools have great potential for diverse applications.

4.
Immunity ; 55(6): 1067-1081.e8, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35659337

RESUMO

Immunoregulatory B cells impede antitumor immunity through unknown features and mechanisms. We report the existence of leucine-tRNA-synthase-2 (LARS2)-expressing B cell (LARS B) subset with a transforming growth factor-ß1 (TGF-ß1)-dominant regulatory feature in both mouse and human progressive colorectal cancer (CRC). Of note, LARS B cells exhibited a leucine nutrient preference and displayed active mitochondrial aminoacyl-tRNA biosynthesis. They were located outside the tertiary lymphoid structure and correlated with colorectal hyperplasia and shortened survival in CRC patients. A leucine diet induced LARS B cell generation, whereas LARS B cell deletion by Lars2 gene ablation or leucine blockage repressed CRC immunoevasion. Mechanistically, LARS2 programmed mitochondrial nicotinamide adenine dinucleotide (NAD+) regeneration and oxidative metabolism, thus determining the regulatory feature of LARS B cells in which the NAD-dependent protein deacetylase sirtuin-1 (SIRT1) was involved. We propose a leucine-dieting scheme to inhibit LARS B cells, which is safe and useful for CRC therapy.


Assuntos
Aminoacil-tRNA Sintetases , Neoplasias Colorretais , Animais , Humanos , Leucina , Camundongos , Mitocôndrias/metabolismo , NAD/metabolismo , RNA de Transferência
5.
Nature ; 613(7942): 60-65, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36288749

RESUMO

Dye-sensitized solar cells (DSCs) convert light into electricity by using photosensitizers adsorbed on the surface of nanocrystalline mesoporous titanium dioxide (TiO2) films along with electrolytes or solid charge-transport materials1-3. They possess many features including transparency, multicolour and low-cost fabrication, and are being deployed in glass facades, skylights and greenhouses4. Recent development of sensitizers5-10, redox mediators11-13 and device structures14 has improved the performance of DSCs, particularly under ambient light conditions14-17. To further enhance their efficiency, it is pivotal to control the assembly of dye molecules on the surface of TiO2 to favour charge generation. Here we report a route of pre-adsorbing a monolayer of a hydroxamic acid derivative on the surface of TiO2 to improve the dye molecular packing and photovoltaic performance of two newly designed co-adsorbed sensitizers that harvest light quantitatively across the entire visible domain. The best performing cosensitized solar cells exhibited a power conversion efficiency of 15.2% (which has been independently confirmed) under a standard air mass of 1.5 global simulated sunlight, and showed long-term operational stability (500 h). Devices with a larger active area of 2.8 cm2 exhibited a power conversion efficiency of 28.4% to 30.2% over a wide range of ambient light intensities, along with high stability. Our findings pave the way for facile access to high-performance DSCs and offer promising prospects for applications as power supplies and battery replacements for low-power electronic devices18-20 that use ambient light as their energy source.

6.
Mol Cell ; 81(20): 4147-4164.e7, 2021 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-34453890

RESUMO

Missense mutations of the tumor suppressor Neurofibromin 2 (NF2/Merlin/schwannomin) result in sporadic to frequent occurrences of tumorigenesis in multiple organs. However, the underlying pathogenicity of NF2-related tumorigenesis remains mostly unknown. Here we found that NF2 facilitated innate immunity by regulating YAP/TAZ-mediated TBK1 inhibition. Unexpectedly, patient-derived individual mutations in the FERM domain of NF2 (NF2m) converted NF2 into a potent suppressor of cGAS-STING signaling. Mechanistically, NF2m gained extreme associations with IRF3 and TBK1 and, upon innate nucleic acid sensing, was directly induced by the activated IRF3 to form cellular condensates, which contained the PP2A complex, to eliminate TBK1 activation. Accordingly, NF2m robustly suppressed STING-initiated antitumor immunity in cancer cell-autonomous and -nonautonomous murine models, and NF2m-IRF3 condensates were evident in human vestibular schwannomas. Our study reports phase separation-mediated quiescence of cGAS-STING signaling by a mutant tumor suppressor and reveals gain-of-function pathogenesis for NF2-related tumors by regulating antitumor immunity.


Assuntos
Imunidade Inata , Proteínas de Membrana/metabolismo , Mutação de Sentido Incorreto , Neoplasias/metabolismo , Neurofibromina 2/metabolismo , Nucleotidiltransferases/metabolismo , Evasão Tumoral , Animais , Feminino , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HEK293 , Humanos , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/metabolismo , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Masculino , Melanoma Experimental/genética , Melanoma Experimental/imunologia , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Proteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/patologia , Neurofibromina 2/genética , Nucleotidiltransferases/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais
7.
Mol Cell ; 80(5): 810-827.e7, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33171123

RESUMO

Mitochondrial morphology shifts rapidly to manage cellular metabolism, organelle integrity, and cell fate. It remains unknown whether innate nucleic acid sensing, the central and general mechanisms of monitoring both microbial invasion and cellular damage, can reprogram and govern mitochondrial dynamics and function. Here, we unexpectedly observed that upon activation of RIG-I-like receptor (RLR)-MAVS signaling, TBK1 directly phosphorylated DRP1/DNM1L, which disabled DRP1, preventing its high-order oligomerization and mitochondrial fragmentation function. The TBK1-DRP1 axis was essential for assembly of large MAVS aggregates and healthy antiviral immunity and underlay nutrient-triggered mitochondrial dynamics and cell fate determination. Knockin (KI) strategies mimicking TBK1-DRP1 signaling produced dominant-negative phenotypes reminiscent of human DRP1 inborn mutations, while interrupting the TBK1-DRP1 connection compromised antiviral responses. Thus, our findings establish an unrecognized function of innate immunity governing both morphology and physiology of a major organelle, identify a lacking loop during innate RNA sensing, and report an elegant mechanism of shaping mitochondrial dynamics.


Assuntos
Dinaminas/metabolismo , Mitocôndrias/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , RNA/metabolismo , Peixe-Zebra/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteína DEAD-box 58/genética , Proteína DEAD-box 58/metabolismo , Dinaminas/genética , Células HCT116 , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Mutação , Proteínas Serina-Treonina Quinases/genética , RNA/genética , Transdução de Sinais/genética , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
8.
Nat Methods ; 21(4): 609-618, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38443507

RESUMO

Precise identification and quantification of amino acids is crucial for many biological applications. Here we report a copper(II)-functionalized Mycobacterium smegmatis porin A (MspA) nanopore with the N91H substitution, which enables direct identification of all 20 proteinogenic amino acids when combined with a machine-learning algorithm. The validation accuracy reaches 99.1%, with 30.9% signal recovery. The feasibility of ultrasensitive quantification of amino acids was also demonstrated at the nanomolar range. Furthermore, the capability of this system for real-time analyses of two representative post-translational modifications (PTMs), one unnatural amino acid and ten synthetic peptides using exopeptidases, including clinically relevant peptides associated with Alzheimer's disease and cancer neoantigens, was demonstrated. Notably, our strategy successfully distinguishes peptides with only one amino acid difference from the hydrolysate and provides the possibility to infer the peptide sequence.


Assuntos
Nanoporos , Aminoácidos/química , Peptídeos/química , Sequência de Aminoácidos , Porinas/química , Porinas/metabolismo
9.
Plant Cell ; 36(6): 2176-2200, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38345432

RESUMO

Phosphorus is indispensable in agricultural production. An increasing food supply requires more efficient use of phosphate due to limited phosphate resources. However, how crops regulate phosphate efficiency remains largely unknown. Here, we identified a major quantitative trait locus, qPE19, that controls 7 low-phosphate (LP)-related traits in soybean (Glycine max) through linkage mapping and genome-wide association studies. We identified the gene responsible for qPE19 as GLYCEROPHOSPHORYL DIESTER PHOSPHODIESTERASE2 (GmGDPD2), and haplotype 5 represents the optimal allele favoring LP tolerance. Overexpression of GmGDPD2 significantly affects hormone signaling and improves root architecture, phosphate efficiency and yield-related traits; conversely, CRISPR/Cas9-edited plants show decreases in these traits. GmMyb73 negatively regulates GmGDPD2 by directly binding to its promoter; thus, GmMyb73 negatively regulates LP tolerance. GmGDPD2 physically interacts with GA 2-oxidase 1 (GmGA2ox1) in the plasma membrane, and overexpressing GmGA2ox1 enhances LP-associated traits, similar to GmGDPD2 overexpression. Analysis of double mutants for GmGDPD2 and GmGA2ox1 demonstrated that GmGDPD2 regulates LP tolerance likely by influencing auxin and gibberellin dose-associated cell division in the root. These results reveal a regulatory module that plays a major role in regulating LP tolerance in soybeans and is expected to be utilized to develop phosphate-efficient varieties to enhance soybean production, particularly in phosphate-deficient soils.


Assuntos
Regulação da Expressão Gênica de Plantas , Glycine max , Fosfatos , Proteínas de Plantas , Glycine max/genética , Glycine max/metabolismo , Fosfatos/metabolismo , Fosfatos/deficiência , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Locos de Características Quantitativas/genética , Plantas Geneticamente Modificadas , Estudo de Associação Genômica Ampla
10.
Nature ; 600(7887): 59-63, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34666339

RESUMO

Mare volcanics on the Moon are the key record of thermo-chemical evolution throughout most of lunar history1-3. Young mare basalts-mainly distributed in a region rich in potassium, rare-earth elements and phosphorus (KREEP) in Oceanus Procellarum, called the Procellarum KREEP Terrane (PKT)4-were thought to be formed from KREEP-rich sources at depth5-7. However, this hypothesis has not been tested with young basalts from the PKT. Here we present a petrological and geochemical study of the basalt clasts from the PKT returned by the Chang'e-5 mission8. These two-billion-year-old basalts are the youngest lunar samples reported so far9. Bulk rock compositions have moderate titanium and high iron contents  with KREEP-like rare-earth-element and high thorium concentrations. However, strontium-neodymium isotopes indicate that these basalts were derived from a non-KREEP mantle source. To produce the high abundances of rare-earth elements and thorium, low-degree partial melting and extensive fractional crystallization are required. Our results indicate that the KREEP association may not be a prerequisite for young mare volcanism. Absolving the need to invoke heat-producing elements in their source implies a more sustained cooling history of the lunar interior to generate the Moon's youngest melts.

11.
Proc Natl Acad Sci U S A ; 121(25): e2406788121, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38865267

RESUMO

Heritable symbionts are common among animals in nature, but the molecular mechanisms underpinning symbiont invasions of host populations have been elusive. In this study, we demonstrate the spread of Rickettsia in an invasive agricultural pest, the whitefly Bemisia tabaci Mediterranean (MED), across northeastern China from 2018 to 2023. Here, we show that the beneficial symbiont Rickettsia spreads by manipulating host hormone signals. Our analyses suggest that Rickettsia have been horizontally acquired by B. tabaci MED from another invasive whitefly B. tabaci Middle East-Asia Minor 1 during periods of coexistence. Rickettsia is transmitted maternally and horizontally from female B. tabaci MED individuals. Rickettsia infection enhances fecundity and results in female bias among whiteflies. Our findings reveal that Rickettsia infection stimulates juvenile hormone (JH) synthesis, in turn enhancing fecundity, copulation events, and the female ratio of the offspring. Consequently, Rickettsia infection results in increased whitefly fecundity and female bias by modulating the JH pathway. More female progeny facilitates the transmission of Rickettsia. This study illustrates that the spread of Rickettsia among invasive whiteflies in northeastern China is propelled by host hormone regulation. Such symbiont invasions lead to rapid physiological and molecular evolution in the host, influencing the biology and ecology of an invasive species.


Assuntos
Fertilidade , Hemípteros , Rickettsia , Razão de Masculinidade , Simbiose , Animais , Rickettsia/fisiologia , Hemípteros/microbiologia , Hemípteros/fisiologia , Feminino , Masculino , Hormônios Juvenis/metabolismo , China
12.
PLoS Genet ; 20(7): e1011339, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38980841

RESUMO

BACKGROUND: Varicose veins (VV) are one of the common human diseases, but the role of genetics in its development is not fully understood. METHODS: We conducted an exome-wide association study of VV using whole-exome sequencing data from the UK Biobank, and focused on common and rare variants using single-variant association analysis and gene-level collapsing analysis. FINDINGS: A total of 13,823,269 autosomal genetic variants were obtained after quality control. We identified 36 VV-related independent common variants mapping to 34 genes by single-variant analysis and three rare variant genes (PIEZO1, ECE1, FBLN7) by collapsing analysis, and most associations between genes and VV were replicated in FinnGen. PIEZO1 was the closest gene associated with VV (P = 5.05 × 10-31), and it was found to reach exome-wide significance in both single-variant and collapsing analyses. Two novel rare variant genes (ECE1 and METTL21A) associated with VV were identified, of which METTL21A was associated only with females. The pleiotropic effects of VV-related genes suggested that body size, inflammation, and pulmonary function are strongly associated with the development of VV. CONCLUSIONS: Our findings highlight the importance of causal genes for VV and provide new directions for treatment.


Assuntos
Sequenciamento do Exoma , Exoma , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Varizes , Humanos , Varizes/genética , Feminino , Masculino , Exoma/genética , Polimorfismo de Nucleotídeo Único , Enzimas Conversoras de Endotelina/genética , Pessoa de Meia-Idade , Variação Genética , Adulto , Canais Iônicos
13.
Proc Natl Acad Sci U S A ; 121(12): e2315707121, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38489388

RESUMO

KCTD10 belongs to the KCTD (potassiumchannel tetramerization domain) family, many members of which are associated with neuropsychiatric disorders. However, the biological function underlying the association with brain disorders remains to be explored. Here, we reveal that Kctd10 is highly expressed in neuronal progenitors and layer V neurons throughout brain development. Kctd10 deficiency triggers abnormal proliferation and differentiation of neuronal progenitors, reduced deep-layer (especially layer V) neurons, increased upper-layer neurons, and lowered brain size. Mechanistically, we screened and identified a unique KCTD10-interacting protein, KCTD13, associated with neurodevelopmental disorders. KCTD10 mediated the ubiquitination-dependent degradation of KCTD13 and KCTD10 ablation resulted in a considerable increase of KCTD13 expression in the developing cortex. KCTD13 overexpression in neuronal progenitors led to reduced proliferation and abnormal cell distribution, mirroring KCTD10 deficiency. Notably, mice with brain-specific Kctd10 knockout exhibited obvious motor deficits. This study uncovers the physiological function of KCTD10 and provides unique insights into the pathogenesis of neurodevelopmental disorders.


Assuntos
Encefalopatias , Transtornos do Neurodesenvolvimento , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Animais , Camundongos , Proteínas/metabolismo , Encéfalo/metabolismo , Neurônios/metabolismo , Transtornos do Neurodesenvolvimento/genética , Encefalopatias/genética , Neurogênese/genética , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo
14.
Genes Dev ; 33(7-8): 382-387, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30808660

RESUMO

Genomic imprinting is an epigenetic mechanism by which genes are expressed in a parental origin-dependent manner. We recently discovered that, like DNA methylation, oocyte-inherited H3K27me3 can also serve as an imprinting mark in mouse preimplantation embryos. In this study, we found H3K27me3 is strongly biased toward the maternal allele with some associated with DNA methylation-independent paternally expressed genes (PEGs) in human morulae. The H3K27me3 domains largely overlap with DNA partially methylated domains (PMDs) and occupy developmental gene promoters. Thus, our study not only reveals the H3K27me3 landscape but also establishes a correlation between maternal-biased H3K27me3 and PEGs in human morulae.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento/genética , Impressão Genômica/genética , Histonas/metabolismo , Mórula/fisiologia , Alelos , Metilação de DNA , Feminino , Histonas/genética , Humanos , Masculino , Regiões Promotoras Genéticas/genética
15.
Plant Cell ; 35(7): 2552-2569, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-36977631

RESUMO

Ralstonia solanacearum is a devastating soil-borne bacterial pathogen capable of infecting many plant species, including tomato (Solanum lycopersicum). However, the perception of Ralstonia by the tomato immune system and the pathogen's counter-defense strategy remain largely unknown. Here, we show that PehC, a specific exo-polygalacturonase secreted by Ralstonia, acts as an elicitor that triggers typical immune responses in tomato and other Solanaceous plants. The elicitor activity of PehC depends on its N-terminal epitope, and not on its polygalacturonase activity. The recognition of PehC specifically occurs in tomato roots and relies on unknown receptor-like kinase(s). Moreover, PehC hydrolyzes plant pectin-derived oligogalacturonic acids (OGs), a type of damage-associated molecular pattern (DAMP), which leads to the release of galacturonic acid (GalA), thereby dampening DAMP-triggered immunity (DTI). Ralstonia depends on PehC for its growth and early infection and can utilize GalA as a carbon source in the xylem. Our findings demonstrate the specialized and dual functions of Ralstonia PehC, which enhance virulence by degrading DAMPs to evade DTI and produce nutrients, a strategy used by pathogens to attenuate plant immunity. Solanaceous plants have evolved to recognize PehC and induce immune responses, which highlights the significance of PehC. Overall, this study provides insight into the arms race between plants and pathogens.


Assuntos
Ralstonia solanacearum , Solanum lycopersicum , Virulência , Poligalacturonase , Proteínas de Bactérias , Doenças das Plantas/microbiologia
16.
Nat Chem Biol ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060393

RESUMO

Phospholipid and nucleotide syntheses are fundamental metabolic processes in eukaryotic organisms, with their dysregulation implicated in various disease states. Despite their importance, the interplay between these pathways remains poorly understood. Using genetic and metabolic analyses in Saccharomyces cerevisiae, we elucidate how cytidine triphosphate usage in the Kennedy pathway for phospholipid synthesis influences nucleotide metabolism and redox balance. We find that deficiencies in the Kennedy pathway limit nucleotide salvage, prompting compensatory activation of de novo nucleotide synthesis and the pentose phosphate pathway. This metabolic shift enhances the production of antioxidants such as NADPH and glutathione. Moreover, we observe that the Kennedy pathway for phospholipid synthesis is inhibited during replicative aging, indicating its role in antioxidative defense as an adaptive mechanism in aged cells. Our findings highlight the critical role of phospholipid synthesis pathway choice in the integrative regulation of nucleotide metabolism, redox balance and membrane properties for cellular defense.

17.
Nat Chem Biol ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553609

RESUMO

Cytosine base editors (CBEs) are effective tools for introducing C-to-T base conversions, but their clinical applications are limited by off-target and bystander effects. Through structure-guided engineering of human APOBEC3A (A3A) deaminase, we developed highly accurate A3A-CBE (haA3A-CBE) variants that efficiently generate C-to-T conversion with a narrow editing window and near-background level of DNA and RNA off-target activity, irrespective of methylation status and sequence context. The engineered deaminase domains are compatible with PAM-relaxed SpCas9-NG variant, enabling accurate correction of pathogenic mutations in homopolymeric cytosine sites through flexible positioning of the single-guide RNAs. Dual adeno-associated virus delivery of one haA3A-CBE variant to a mouse model of tyrosinemia induced up to 58.1% editing in liver tissues with minimal bystander editing, which was further reduced through single dose of lipid nanoparticle-based messenger RNA delivery of haA3A-CBEs. These results highlight the tremendous promise of haA3A-CBEs for precise genome editing to treat human diseases.

19.
J Immunol ; 212(11): 1714-1721, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38598411

RESUMO

Ag-specific effector CD4+ T cells play a crucial role in defending against exogenous pathogens. However, the mechanisms governing the differentiation and function of IFN-γ-producing effector CD4+ Th1 cells in immune responses remain largely unknown. In this study, we elucidated the pivotal role of zinc finger protein 335 (Zfp335) in regulating effector Th1 cell differentiation and survival during acute bacterial infection. Mice with Zfp335 knockout in OT-II cells exhibited impaired Ag-specific CD4+ T cell expansion accompanied by a significant reduction in resistance to Listeria infection. Furthermore, Zfp335 deficiency restricted the effector CD4+ Th1 cell population and compromised their survival upon Listeria challenge. The expression of T-bet and IFN-γ was accordingly decreased in Zfp335-deficient Th1 cells. Mechanistically, Zfp335 directly bound to the promoter region of the Lmna gene and regulated its expression. Overexpression of Lmna was able to rescue the survival and function of Zfp335-deficient effector Th1 cells. Therefore, our study provides novel insights into the mechanisms governing effector Th1 cell differentiation and survival during acute infection.


Assuntos
Diferenciação Celular , Proteínas de Ligação a DNA , Lamina Tipo A , Camundongos Knockout , Células Th1 , Fatores de Transcrição , Animais , Camundongos , Diferenciação Celular/imunologia , Diferenciação Celular/genética , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica/imunologia , Interferon gama/imunologia , Interferon gama/metabolismo , Lamina Tipo A/genética , Listeriose/imunologia , Camundongos Endogâmicos C57BL , Células Th1/imunologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
20.
Nature ; 581(7808): 303-309, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32214235

RESUMO

Single-cell analysis is a valuable tool for dissecting cellular heterogeneity in complex systems1. However, a comprehensive single-cell atlas has not been achieved for humans. Here we use single-cell mRNA sequencing to determine the cell-type composition of all major human organs and construct a scheme for the human cell landscape (HCL). We have uncovered a single-cell hierarchy for many tissues that have not been well characterized. We established a 'single-cell HCL analysis' pipeline that helps to define human cell identity. Finally, we performed a single-cell comparative analysis of landscapes from human and mouse to identify conserved genetic networks. We found that stem and progenitor cells exhibit strong transcriptomic stochasticity, whereas differentiated cells are more distinct. Our results provide a useful resource for the study of human biology.


Assuntos
Células/citologia , Células/metabolismo , Análise de Célula Única/métodos , Adulto , Animais , Povo Asiático , Diferenciação Celular , Linhagem Celular , Separação Celular , China , Bases de Dados Factuais , Corpos Embrioides/citologia , Corpos Embrioides/metabolismo , Etnicidade , Feto/citologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Imunidade , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/metabolismo , Camundongos , Especificidade de Órgãos , RNA Mensageiro/análise , RNA Mensageiro/genética , Análise de Sequência de RNA , Análise de Célula Única/instrumentação , Processos Estocásticos
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