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1.
Cell ; 187(6): 1422-1439.e24, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38447573

RESUMO

Neutrophils, the most abundant and efficient defenders against pathogens, exert opposing functions across cancer types. However, given their short half-life, it remains challenging to explore how neutrophils adopt specific fates in cancer. Here, we generated and integrated single-cell neutrophil transcriptomes from 17 cancer types (225 samples from 143 patients). Neutrophils exhibited extraordinary complexity, with 10 distinct states including inflammation, angiogenesis, and antigen presentation. Notably, the antigen-presenting program was associated with favorable survival in most cancers and could be evoked by leucine metabolism and subsequent histone H3K27ac modification. These neutrophils could further invoke both (neo)antigen-specific and antigen-independent T cell responses. Neutrophil delivery or a leucine diet fine-tuned the immune balance to enhance anti-PD-1 therapy in various murine cancer models. In summary, these data not only indicate the neutrophil divergence across cancers but also suggest therapeutic opportunities such as antigen-presenting neutrophil delivery.


Assuntos
Apresentação de Antígeno , Neoplasias , Neutrófilos , Animais , Humanos , Camundongos , Antígenos de Neoplasias , Leucina/metabolismo , Neoplasias/imunologia , Neoplasias/patologia , Neutrófilos/metabolismo , Linfócitos T , Análise da Expressão Gênica de Célula Única
2.
Cell ; 185(16): 3008-3024.e16, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35870449

RESUMO

Here, we report inducible mosaic animal for perturbation (iMAP), a transgenic platform enabling in situ CRISPR targeting of at least 100 genes in parallel throughout the mouse body. iMAP combines Cre-loxP and CRISPR-Cas9 technologies and utilizes a germline-transmitted transgene carrying a large array of individually floxed, tandemly linked gRNA-coding units. Cre-mediated recombination triggers expression of all the gRNAs in the array but only one of them per cell, converting the mice to mosaic organisms suitable for phenotypic characterization and also for high-throughput derivation of conventional single-gene perturbation lines via breeding. Using gRNA representation as a readout, we mapped a miniature Perturb-Atlas cataloging the perturbations of 90 genes across 39 tissues, which yields rich insights into context-dependent gene functions and provides a glimpse of the potential of iMAP in genome decoding.


Assuntos
Sistemas CRISPR-Cas , RNA Guia de Cinetoplastídeos , Animais , Sistemas CRISPR-Cas/genética , Edição de Genes , Genoma , Camundongos , RNA Guia de Cinetoplastídeos/genética , RNA Guia de Cinetoplastídeos/metabolismo , Transgenes
3.
Nat Immunol ; 24(11): 1839-1853, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37749326

RESUMO

The APOE4 allele is the strongest genetic risk factor for late-onset Alzheimer's disease (AD). The contribution of microglial APOE4 to AD pathogenesis is unknown, although APOE has the most enriched gene expression in neurodegenerative microglia (MGnD). Here, we show in mice and humans a negative role of microglial APOE4 in the induction of the MGnD response to neurodegeneration. Deletion of microglial APOE4 restores the MGnD phenotype associated with neuroprotection in P301S tau transgenic mice and decreases pathology in APP/PS1 mice. MGnD-astrocyte cross-talk associated with ß-amyloid (Aß) plaque encapsulation and clearance are mediated via LGALS3 signaling following microglial APOE4 deletion. In the brains of AD donors carrying the APOE4 allele, we found a sex-dependent reciprocal induction of AD risk factors associated with suppression of MGnD genes in females, including LGALS3, compared to individuals homozygous for the APOE3 allele. Mechanistically, APOE4-mediated induction of ITGB8-transforming growth factor-ß (TGFß) signaling impairs the MGnD response via upregulation of microglial homeostatic checkpoints, including Inpp5d, in mice. Deletion of Inpp5d in microglia restores MGnD-astrocyte cross-talk and facilitates plaque clearance in APP/PS1 mice. We identify the microglial APOE4-ITGB8-TGFß pathway as a negative regulator of microglial response to AD pathology, and restoring the MGnD phenotype via blocking ITGB8-TGFß signaling provides a promising therapeutic intervention for AD.


Assuntos
Doença de Alzheimer , Feminino , Camundongos , Humanos , Animais , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Apolipoproteína E4/genética , Apolipoproteína E4/metabolismo , Microglia/metabolismo , Galectina 3/genética , Galectina 3/metabolismo , Peptídeos beta-Amiloides/metabolismo , Camundongos Transgênicos , Modelos Animais de Doenças
4.
Immunity ; 52(5): 767-781.e6, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32277911

RESUMO

The enzyme cyclic GMP-AMP synthase (cGAS) senses cytosolic DNA in infected and malignant cells and catalyzes the formation of 2'3'cGMP-AMP (cGAMP), which in turn triggers interferon (IFN) production via the STING pathway. Here, we examined the contribution of anion channels to cGAMP transfer and anti-viral defense. A candidate screen revealed that inhibition of volume-regulated anion channels (VRACs) increased propagation of the DNA virus HSV-1 but not the RNA virus VSV. Chemical blockade or genetic ablation of LRRC8A/SWELL1, a VRAC subunit, resulted in defective IFN responses to HSV-1. Biochemical and electrophysiological analyses revealed that LRRC8A/LRRC8E-containing VRACs transport cGAMP and cyclic dinucleotides across the plasma membrane. Enhancing VRAC activity by hypotonic cell swelling, cisplatin, GTPγS, or the cytokines TNF or interleukin-1 increased STING-dependent IFN response to extracellular but not intracellular cGAMP. Lrrc8e-/- mice exhibited impaired IFN responses and compromised immunity to HSV-1. Our findings suggest that cell-to-cell transmission of cGAMP via LRRC8/VRAC channels is central to effective anti-viral immunity.


Assuntos
Fibroblastos/imunologia , Interferons/imunologia , Proteínas de Membrana/imunologia , Nucleotídeos Cíclicos/imunologia , Canais de Ânion Dependentes de Voltagem/imunologia , Animais , Antivirais/imunologia , Antivirais/metabolismo , Efeito Espectador , Linhagem Celular , Células Cultivadas , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Células HeLa , Herpes Simples/imunologia , Herpes Simples/virologia , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 1/fisiologia , Humanos , Interferons/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nucleotídeos Cíclicos/metabolismo , Nucleotidiltransferases/genética , Nucleotidiltransferases/imunologia , Nucleotidiltransferases/metabolismo , Canais de Ânion Dependentes de Voltagem/metabolismo
5.
Nat Immunol ; 16(6): 642-52, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25915733

RESUMO

Fungal infection stimulates the canonical C-type lectin receptor (CLR) signaling pathway via activation of the tyrosine kinase Syk. Here we identify a crucial role for the tyrosine phosphatase SHP-2 in mediating CLR-induced activation of Syk. Ablation of the gene encoding SHP-2 (Ptpn11; called 'Shp-2' here) in dendritic cells (DCs) and macrophages impaired Syk-mediated signaling and abrogated the expression of genes encoding pro-inflammatory molecules following fungal stimulation. Mechanistically, SHP-2 operated as a scaffold, facilitating the recruitment of Syk to the CLR dectin-1 or the adaptor FcRγ, through its N-SH2 domain and a previously unrecognized carboxy-terminal immunoreceptor tyrosine-based activation motif (ITAM). We found that DC-derived SHP-2 was crucial for the induction of interleukin 1ß (IL-1ß), IL-6 and IL-23 and anti-fungal responses of the TH17 subset of helper T cells in controlling infection with Candida albicans. Together our data reveal a mechanism by which SHP-2 mediates the activation of Syk in response to fungal infection.


Assuntos
Candidíase/imunologia , Células Dendríticas/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Macrófagos/fisiologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteínas Tirosina Quinases/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Células Th17/imunologia , Motivos de Aminoácidos/genética , Animais , Antígenos de Fungos/imunologia , Células Cultivadas , Citocinas/metabolismo , Ativação Enzimática , Mediadores da Inflamação/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Ativação Linfocitária , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Receptores de IgE/genética , Receptores de IgE/metabolismo , Transdução de Sinais , Quinase Syk
6.
Plant Cell ; 36(2): 227-245, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37772963

RESUMO

Biomolecular condensates are dynamic structures formed through diverse mechanisms, including liquid-liquid phase separation. These condensates have emerged as crucial regulators of cellular processes in eukaryotic cells, enabling the compartmentalization of specific biological reactions while allowing for dynamic exchange of molecules with the surrounding environment. RNA silencing, a conserved gene regulatory mechanism mediated by small RNAs (sRNAs), plays pivotal roles in various biological processes. Multiple types of biomolecular condensate, including dicing bodies, processing bodies, small interfering RNA bodies, and Cajal bodies, have been identified as key players in RNA silencing pathways. These biomolecular condensates provide spatial compartmentation for the biogenesis, loading, action, and turnover of small RNAs. Moreover, they actively respond to stresses, such as viral infections, and modulate RNA silencing activities during stress responses. This review summarizes recent advances in understanding of dicing bodies and other biomolecular condensates involved in RNA silencing. We explore their formation, roles in RNA silencing, and contributions to antiviral resistance responses. This comprehensive overview provides insights into the functional significance of biomolecular condensates in RNA silencing and expands our understanding of their roles in gene expression and stress responses in plants.


Assuntos
Condensados Biomoleculares , RNA , Interferência de RNA , Células Eucarióticas , RNA Interferente Pequeno , Separação de Fases
7.
Plant Cell ; 35(2): 717-737, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36472157

RESUMO

Increasing planting density has been adopted as an effective means to increase maize (Zea mays) yield. Competition for light from neighbors can trigger plant shade avoidance syndrome, which includes accelerated flowering. However, the regulatory networks of maize inflorescence development in response to high-density planting remain poorly understood. In this study, we showed that shade-mimicking treatments cause precocious development of the tassels and ears. Comparative transcriptome profiling analyses revealed the enrichment of phytohormone-related genes and transcriptional regulators among the genes co-regulated by developmental progression and simulated shade. Network analysis showed that three homologous Squamosa promoter binding protein (SBP)-like (SPL) transcription factors, Unbranched2 (UB2), Unbranched3 (UB3), and Tasselsheath4 (TSH4), individually exhibited connectivity to over 2,400 genes across the V3-to-V9 stages of tassel development. In addition, we showed that the ub2 ub3 double mutant and tsh4 single mutant were almost insensitive to simulated shade treatments. Moreover, we demonstrated that UB2/UB3/TSH4 could directly regulate the expression of Barren inflorescence2 (BIF2) and Zea mays teosinte branched1/cycloidea/proliferating cell factor30 (ZmTCP30). Furthermore, we functionally verified a role of ZmTCP30 in regulating tassel branching and ear development. Our results reveal a UB2/UB3/TSH4-anchored transcriptional regulatory network of maize inflorescence development and provide valuable targets for breeding shade-tolerant maize cultivars.


Assuntos
Inflorescência , Zea mays , Inflorescência/genética , Inflorescência/metabolismo , Zea mays/metabolismo , Redes Reguladoras de Genes , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
8.
Immunity ; 46(2): 301-314, 2017 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-28228284

RESUMO

Respiratory syncytial virus (RSV) is the major cause of lower respiratory tract infections in infants and is characterized by pulmonary infiltration of B cells in fatal cases. We analyzed the B cell compartment in human newborns and identified a population of neonatal regulatory B lymphocytes (nBreg cells) that produced interleukin 10 (IL-10) in response to RSV infection. The polyreactive B cell receptor of nBreg cells interacted with RSV protein F and induced upregulation of chemokine receptor CX3CR1. CX3CR1 interacted with RSV glycoprotein G, leading to nBreg cell infection and IL-10 production that dampened T helper 1 (Th1) cytokine production. In the respiratory tract of neonates with severe RSV-induced acute bronchiolitis, RSV-infected nBreg cell frequencies correlated with increased viral load and decreased blood memory Th1 cell frequencies. Thus, the frequency of nBreg cells is predictive of the severity of acute bronchiolitis disease and nBreg cell activity may constitute an early-life host response that favors microbial pathogenesis.


Assuntos
Linfócitos B Reguladores/imunologia , Bronquiolite Viral/imunologia , Receptores de Quimiocinas/imunologia , Infecções por Vírus Respiratório Sincicial/imunologia , Linfócitos B Reguladores/virologia , Bronquiolite Viral/patologia , Linfócitos T CD4-Positivos/imunologia , Receptor 1 de Quimiocina CX3C , Ensaio de Imunoadsorção Enzimática , ELISPOT , Perfilação da Expressão Gênica , Humanos , Recém-Nascido , Ativação Linfocitária/imunologia , Análise de Sequência com Séries de Oligonucleotídeos , Infecções por Vírus Respiratório Sincicial/patologia , Vírus Sinciciais Respiratórios , Transcriptoma
9.
Proc Natl Acad Sci U S A ; 120(37): e2309221120, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37669383

RESUMO

Emerging evidence suggests that dysregulation of neuroinflammation, particularly that orchestrated by microglia, plays a significant role in the pathogenesis of Alzheimer's disease (AD). Danger signals including dead neurons, dystrophic axons, phosphorylated tau, and amyloid plaques alter the functional phenotype of microglia from a homeostatic (M0) to a neurodegenerative or disease-associated phenotype, which in turn drives neuroinflammation and promotes disease. Thus, therapies that target microglia activation constitute a unique approach for treating AD. Here, we report that nasally administered anti-CD3 monoclonal antibody in the 3xTg AD mouse model reduced microglial activation and improved cognition independent of amyloid beta deposition. In addition, gene expression analysis demonstrated decreased oxidative stress, increased axogenesis and synaptic organization, and metabolic changes in the hippocampus and cortex of nasal anti-CD3 treated animals. The beneficial effect of nasal anti-CD3 was associated with the accumulation of T cells in the brain where they were in close contact with microglial cells. Taken together, our findings identify nasal anti-CD3 as a unique form of immunotherapy to treat Alzheimer's disease independent of amyloid beta targeting.


Assuntos
Doença de Alzheimer , Animais , Camundongos , Administração Intranasal , Peptídeos beta-Amiloides , Doenças Neuroinflamatórias , Anticorpos Monoclonais , Modelos Animais de Doenças
10.
PLoS Pathog ; 19(5): e1011340, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37167200

RESUMO

Robust plant immune systems are fine-tuned by both protein-coding genes and non-coding RNAs. Long non-coding RNAs (lncRNAs) refer to RNAs with a length of more than 200 nt and usually do not have protein-coding function and do not belong to any other well-known non-coding RNA types. The non-protein-coding, low expression, and non-conservative characteristics of lncRNAs restrict their recognition. Although studies of lncRNAs in plants are in the early stage, emerging studies have shown that plants employ lncRNAs to regulate plant immunity. Moreover, in response to stresses, numerous lncRNAs are differentially expressed, which manifests the actions of low-expressed lncRNAs and makes plant-microbe/insect interactions a convenient system to study the functions of lncRNAs. Here, we summarize the current advances in plant lncRNAs, discuss their regulatory effects in different stages of plant immunity, and highlight their roles in diverse plant-microbe/insect interactions. These insights will not only strengthen our understanding of the roles and actions of lncRNAs in plant-microbe/insect interactions but also provide novel insight into plant immune responses and a basis for further research in this field.


Assuntos
RNA Longo não Codificante , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Imunidade Vegetal/genética , Regulação da Expressão Gênica de Plantas , RNA de Plantas/genética
11.
PLoS Pathog ; 19(1): e1011085, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36706160

RESUMO

Neutralizing antibodies (nAbs) are important assets to fight COVID-19, but most existing nAbs lose the activities against Omicron subvariants. Here, we report a human monoclonal antibody (Ab08) isolated from a convalescent patient infected with the prototype strain (Wuhan-Hu-1). Ab08 binds to the receptor-binding domain (RBD) with pico-molar affinity (230 pM), effectively neutralizes SARS-CoV-2 and variants of concern (VOCs) including Alpha, Beta, Gamma, Mu, Omicron BA.1 and BA.2, and to a lesser extent for Delta and Omicron BA.4/BA.5 which bear the L452R mutation. Of medical importance, Ab08 shows therapeutic efficacy in SARS-CoV-2-infected hACE2 mice. X-ray crystallography of the Ab08-RBD complex reveals an antibody footprint largely in the ß-strand core and away from the ACE2-binding motif. Negative staining electron-microscopy suggests a neutralizing mechanism through which Ab08 destructs the Spike trimer. Together, our work identifies a nAb with therapeutic potential for COVID-19.


Assuntos
Anticorpos Monoclonais , COVID-19 , SARS-CoV-2 , Animais , Humanos , Camundongos , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/uso terapêutico , Glicoproteína da Espícula de Coronavírus/genética
12.
Nucleic Acids Res ; 51(8): 3820-3835, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-36912090

RESUMO

Natural transformation is one of the major mechanisms of horizontal gene transfer. Although it is usually studied using purified DNA in the laboratory, recent studies showed that many naturally competent bacteria acquired exogenous DNA from neighboring donor cells. Our previous work indicates that cell-to-cell natural transformation (CTCNT) using two different Bacillus subtilis strains is a highly efficient process; however, the mechanism is unclear. In this study, we further characterized CTCNT and mapped the transferred DNA in the recombinants using whole genome sequencing. We found that a recombinant strain generated by CTCNT received up to 66 transferred DNA segments; the average length of acquired continuous DNA stretches was approximately 27 kb with a maximum length of 347 kb. Moreover, up to 1.54 Mb genomic DNA (37% of the chromosome) was transferred from the donors into one recipient cell. These results suggest that B. subtilis CTCNT facilitates horizontal gene transfer by increasing the transfer of DNA segments and fostering the exchange of large continuous genomic regions. This indicates that the potency of bacterial natural transformation is underestimated using traditional approaches and reveals that DNA donor cells may play an important role in the transformation process in natural environments.


Assuntos
Bacillus subtilis , Transformação Bacteriana , Bacillus subtilis/genética , DNA/genética , DNA Bacteriano/genética , Genoma , Genômica
13.
Proc Natl Acad Sci U S A ; 119(40): e2200421119, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36161951

RESUMO

Strong ultraviolet (UV) radiation at high altitude imposes a serious selective pressure, which may induce skin pigmentation adaptation of indigenous populations. We conducted skin pigmentation phenotyping and genome-wide analysis of Tibetans in order to understand the underlying mechanism of adaptation to UV radiation. We observe that Tibetans have darker baseline skin color compared with lowland Han Chinese, as well as an improved tanning ability, suggesting a two-level adaptation to boost their melanin production. A genome-wide search for the responsible genes identifies GNPAT showing strong signals of positive selection in Tibetans. An enhancer mutation (rs75356281) located in GNPAT intron 2 is enriched in Tibetans (58%) but rare in other world populations (0 to 18%). The adaptive allele of rs75356281 is associated with darker skin in Tibetans and, under UVB treatment, it displays higher enhancer activities compared with the wild-type allele in in vitro luciferase assays. Transcriptome analyses of gene-edited cells clearly show that with UVB treatment, the adaptive variant of GNPAT promotes melanin synthesis, likely through the interactions of CAT and ACAA1 in peroxisomes with other pigmentation genes, and they act synergistically, leading to an improved tanning ability in Tibetans for UV protection.


Assuntos
Adaptação Fisiológica , Altitude , Pigmentação da Pele , Aciltransferases/genética , Adaptação Fisiológica/genética , Etnicidade , Humanos , Melaninas/genética , Fenótipo , Pigmentação da Pele/genética , Tibet , Transcriptoma , Raios Ultravioleta
14.
BMC Biol ; 22(1): 7, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233907

RESUMO

BACKGROUND: Mosquitoes transmit many infectious diseases that affect human health. The fungus Beauveria bassiana is a biological pesticide that is pathogenic to mosquitoes but harmless to the environment. RESULTS: We found a microRNA (miRNA) that can modulate the antifungal immunity of Aedes aegypti by inhibiting its cognate serine protease. Fungal infection can induce the expression of modular serine protease (ModSP), and ModSP knockdown mosquitoes were more sensitive to B. bassiana infection. The novel miRNA-novel-53 is linked to antifungal immune response and was greatly diminished in infected mosquitoes. The miRNA-novel-53 could bind to the coding sequences of ModSP and impede its expression. Double fluorescence in situ hybridization (FISH) showed that this inhibition occurred in the cytoplasm. The amount of miRNA-novel-53 increased after miRNA agomir injection. This resulted in a significant decrease in ModSP transcript and a significant increase in mortality after fungal infection. An opposite effect was produced after antagomir injection. The miRNA-novel-53 was also knocked out using CRISPR-Cas9, which increased mosquito resistance to the fungus B. bassiana. Moreover, mosquito novel-circ-930 can affect ModSP mRNA by interacting with miRNA-novel-53 during transfection with siRNA or overexpression plasmid. CONCLUSIONS: Novel-circ-930 affects the expression level of ModSP by a novel-circ-930/miRNA-novel-53/ModSP mechanism to modulate antifungal immunity, revealing new information on innate immunity in insects.


Assuntos
Aedes , MicroRNAs , Micoses , Animais , Humanos , Aedes/genética , Aedes/microbiologia , MicroRNAs/genética , RNA Circular , Serina Proteases/genética , Antifúngicos , Hibridização in Situ Fluorescente , Fungos/genética , Serina Endopeptidases
15.
Nano Lett ; 24(9): 2705-2711, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38240732

RESUMO

Two-dimensional (2D) hybrid organic-inorganic perovskites (HOIPs) with enhanced stability, high tunability, and strong spin-orbit coupling have shown great potential in vast applications. Here, we extend the already rich functionality of 2D HOIPs to a new territory, realizing topological superconductivity and Majorana modes for fault-tolerant quantum computation. Especially, we predict that room-temperature ferroelectric BA2PbCl4 (BA for benzylammonium) exhibits topological nodal-point superconductivity (NSC) and gapless Majorana modes on selected edges and ferroelectric domain walls when proximity-coupled to an s-wave superconductor and an in-plane Zeeman field, attractive for experimental verification and application. Since NSC is protected by spatial symmetry of 2D HOIPs, we envision more exotic topological superconducting states to be found in this class of materials due to their diverse noncentrosymmetric space groups, which may open a new avenue in the fields of HOIPs and topological superconductivity.

16.
EMBO J ; 39(22): e104748, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-33058207

RESUMO

Programmable A > I RNA editing is a valuable tool for basic research and medicine. A variety of editors have been created, but a genetically encoded editor that is both precise and efficient has not been described to date. The trade-off between precision and efficiency is exemplified in the state of the art editor REPAIR, which comprises the ADAR2 deaminase domain fused to dCas13b. REPAIR is highly efficient, but also causes significant off-target effects. Mutations that weaken the deaminase domain can minimize the undesirable effects, but this comes at the expense of on-target editing efficiency. We have now overcome this dilemma by using a multipronged approach: We have chosen an alternative Cas protein (CasRx), inserted the deaminase domain into the middle of CasRx, and redirected the editor to the nucleus. The new editor created, dubbed REPAIRx, is precise yet highly efficient, outperforming various previous versions on both mRNA and nuclear RNA targets. Thus, REPAIRx markedly expands the RNA editing toolkit and illustrates a novel strategy for base editor optimization.


Assuntos
Edição de Genes/métodos , Edição de RNA , RNA/metabolismo , Adenosina Desaminase/genética , Células HEK293 , Humanos , Mutação , Proteínas de Ligação a RNA/genética , Transcriptoma
17.
EMBO J ; 39(22): e104741, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-33058229

RESUMO

Programmable RNA cytidine deamination has recently been achieved using a bifunctional editor (RESCUE-S) capable of deaminating both adenine and cysteine. Here, we report the development of "CURE", the first cytidine-specific C-to-U RNA Editor. CURE comprises the cytidine deaminase enzyme APOBEC3A fused to dCas13 and acts in conjunction with unconventional guide RNAs (gRNAs) designed to induce loops at the target sites. Importantly, CURE does not deaminate adenosine, enabling the high-specificity versions of CURE to create fewer missense mutations than RESCUE-S at the off-targets transcriptome-wide. The two editing approaches exhibit overlapping editing motif preferences, with CURE and RESCUE-S being uniquely able to edit UCC and AC motifs, respectively, while they outperform each other at different subsets of the UC targets. Finally, a nuclear-localized version of CURE, but not that of RESCUE-S, can efficiently edit nuclear RNAs. Thus, CURE and RESCUE are distinct in design and complementary in utility.


Assuntos
Citidina Desaminase/genética , Proteínas/genética , Edição de RNA , Núcleo Celular/metabolismo , Células HEK293 , Humanos , RNA/química , RNA/metabolismo , RNA Guia de Cinetoplastídeos , Transcriptoma
18.
BMC Plant Biol ; 24(1): 358, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38698337

RESUMO

BACKGROUND: Astragalus membranaceus var. mongholicus (Astragalus), acknowledged as a pivotal "One Root of Medicine and Food", boasts dual applications in both culinary and medicinal domains. The growth and metabolite accumulation of medicinal roots during the harvest period is intricately regulated by a transcriptional regulatory network. One key challenge is to accurately pinpoint the harvest date during the transition from conventional yield content of medicinal materials to high and to identify the core regulators governing such a critical transition. To solve this problem, we performed a correlation analysis of phenotypic, transcriptome, and metabolome dynamics during the harvesting of Astragalus roots. RESULTS: First, our analysis identified stage-specific expression patterns for a significant proportion of the Astragalus root genes and unraveled the chronology of events that happen at the early and later stages of root harvest. Then, the results showed that different root developmental stages can be depicted by co-expressed genes of Astragalus. Moreover, we identified the key components and transcriptional regulation processes that determine root development during harvest. Furthermore, through correlating phenotypes, transcriptomes, and metabolomes at different harvesting periods, period D (Nov.6) was identified as the critical period of yield and flavonoid content increase, which is consistent with morphological and metabolic changes. In particular, we identified a flavonoid biosynthesis metabolite, isoliquiritigenin, as a core regulator of the synthesis of associated secondary metabolites in Astragalus. Further analyses and experiments showed that HMGCR, 4CL, CHS, and SQLE, along with its associated differentially expressed genes, induced conversion of metabolism processes, including the biosynthesis of isoflavones and triterpenoid saponins substances, thus leading to the transition to higher medicinal materials yield and active ingredient content. CONCLUSIONS: The findings of this work will clarify the differences in the biosynthetic mechanism of astragaloside IV and calycosin 7-O-ß-D-glucopyranoside accumulation between the four harvesting periods, which will guide the harvesting and production of Astragalus.


Assuntos
Astragalus propinquus , Metabolômica , Fenótipo , Raízes de Plantas , Plantas Medicinais , Transcriptoma , Astragalus propinquus/metabolismo , Astragalus propinquus/genética , Astragalus propinquus/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Plantas Medicinais/metabolismo , Plantas Medicinais/genética , Plantas Medicinais/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Metaboloma , Perfilação da Expressão Gênica
19.
Mod Pathol ; 37(6): 100493, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38615709

RESUMO

Demand for anal cancer screening is expected to rise following the recent publication of the Anal Cancer-HSIL Outcomes Research trial, which showed that treatment of high-grade squamous intraepithelial lesions significantly reduces the rate of progression to anal cancer. While screening for human papillomavirus-associated squamous lesions in the cervix is well established and effective, this is less true for other sites in the lower anogenital tract. Current anal cancer screening and prevention rely on high-resolution anoscopy with biopsies. This procedure has a steep learning curve for providers and may cause patient discomfort. Scattering-based light-sheet microscopy (sLSM) is a novel imaging modality with the potential to mitigate these challenges through real-time, microscopic visualization of disease-susceptible tissue. Here, we report a proof-of-principle study that establishes feasibility of dysplasia detection using an sLSM device. We imaged 110 anal biopsy specimens collected prospectively at our institution's dysplasia clinic (including 30 nondysplastic, 40 low-grade squamous intraepithelial lesion, and 40 high-grade squamous intraepithelial lesion specimens) and found that these optical images are highly interpretable and accurately recapitulate histopathologic features traditionally used for the diagnosis of human papillomavirus-associated squamous dysplasia. A reader study to assess diagnostic accuracy suggests that sLSM images are noninferior to hematoxylin and eosin images for the detection of anal dysplasia (sLSM accuracy = 0.87; hematoxylin and eosin accuracy = 0.80; P = .066). Given these results, we believe that sLSM technology holds great potential to enhance the efficacy of anal cancer screening by allowing accurate sampling of diagnostic tissue at the time of anoscopy. While the current imaging study was performed on ex vivo biopsy specimens, we are currently developing a handheld device for in vivo imaging that will provide immediate microscopic guidance to high-resolution anoscopy providers.


Assuntos
Neoplasias do Ânus , Infecções por Papillomavirus , Estudo de Prova de Conceito , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Canal Anal/virologia , Canal Anal/patologia , Canal Anal/diagnóstico por imagem , Neoplasias do Ânus/virologia , Neoplasias do Ânus/patologia , Neoplasias do Ânus/diagnóstico por imagem , Biópsia , Papillomavirus Humano , Microscopia/métodos , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/patologia , Lesões Intraepiteliais Escamosas/virologia , Lesões Intraepiteliais Escamosas/patologia
20.
Am J Kidney Dis ; 83(2): 208-215, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37741609

RESUMO

RATIONALE & OBJECTIVE: Frailty is common in individuals with chronic kidney disease (CKD) and increases the risk of adverse outcomes in adults with kidney failure requiring dialysis. However, this relationship has not been thoroughly evaluated among those with non-dialysis-dependent CKD. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 2,539 adults in the Chronic Renal Insufficiency Cohort Study. EXPOSURE: Frailty status assessed using 5 criteria: slow gait speed, muscle weakness, low physical activity, exhaustion, and unintentional weight loss. OUTCOME: Atherosclerotic events, incident heart failure, all-cause death, and cardiovascular death. ANALYTICAL APPROACH: Cause-specific hazards models. RESULTS: At study entry, the participants' mean age was 62 years, 46% were female, the mean estimated glomerular filtration rate was 45.4mL/min/1.73m2, and the median urine protein was 0.2mg/day. Frailty status was as follows: 12% frail, 51% prefrail, and 37% nonfrail. Over a median follow-up of 11.4 years, there were 393 atherosclerotic events, 413 heart failure events, 497 deaths, and 132 cardiovascular deaths. In multivariable regression analyses, compared with nonfrailty, both frailty and prefrailty status were each associated with higher risk of an atherosclerotic event (HR, 2.03 [95% CI, 1.41-2.91] and 1.77 [95% CI, 1.35-2.31], respectively) and incident heart failure (HR, 2.22 [95% CI, 1.59-3.10] and 1.39 [95% CI, 1.07-1.82], respectively), as well as higher risk of all-cause death (HR, 2.52 [95% CI, 1.84-3.45] and 1.76 [95% CI, 1.37-2.24], respectively) and cardiovascular death (HR, 3.01 [95% CI, 1.62-5.62] and 1.78 [95% 1.06-2.99], respectively). LIMITATIONS: Self-report of aspects of the frailty assessment and comorbidities, which may have led to bias in some estimates. CONCLUSIONS: In adults with CKD, frailty status was associated with higher risk of cardiovascular events and mortality. Future studies are needed to evaluate the impact of interventions to reduce frailty on cardiovascular outcomes in this population. PLAIN-LANGUAGE SUMMARY: Frailty is common in individuals with chronic kidney disease (CKD) and increases the risk of adverse outcomes. We sought to evaluate the association of frailty status with cardiovascular events and death in adults with CKD. Frailty was assessed according to the 5 phenotypic criteria detailed by Fried and colleagues. Among 2,539 participants in the CRIC Study, we found that 12% were frail, 51% were prefrail, and 37% were nonfrail. Frailty status was associated with an increased risk of atherosclerotic events, incident heart failure, and death.


Assuntos
Aterosclerose , Fragilidade , Insuficiência Cardíaca , Insuficiência Renal Crônica , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Estudos de Coortes , Estudos Prospectivos , Fragilidade/epidemiologia , Fragilidade/complicações , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/epidemiologia , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/complicações , Aterosclerose/epidemiologia , Aterosclerose/etiologia
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