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1.
Cell ; 186(24): 5363-5374.e16, 2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-37972591

RESUMO

Cav1.2 channels play crucial roles in various neuronal and physiological processes. Here, we present cryo-EM structures of human Cav1.2, both in its apo form and in complex with several drugs, as well as the peptide neurotoxin calciseptine. Most structures, apo or bound to calciseptine, amlodipine, or a combination of amiodarone and sofosbuvir, exhibit a consistent inactivated conformation with a sealed gate, three up voltage-sensing domains (VSDs), and a down VSDII. Calciseptine sits on the shoulder of the pore domain, away from the permeation path. In contrast, when pinaverium bromide, an antispasmodic drug, is inserted into a cavity reminiscent of the IFM-binding site in Nav channels, a series of structural changes occur, including upward movement of VSDII coupled with dilation of the selectivity filter and its surrounding segments in repeat III. Meanwhile, S4-5III merges with S5III to become a single helix, resulting in a widened but still non-conductive intracellular gate.


Assuntos
Canais de Cálcio Tipo L , Venenos Elapídicos , Humanos , Canais de Cálcio Tipo L/química , Canais de Cálcio Tipo L/metabolismo , Neurotoxinas , Domínios Proteicos , Microscopia Crioeletrônica
2.
Cell ; 172(1-2): 90-105.e23, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29249359

RESUMO

R-2-hydroxyglutarate (R-2HG), produced at high levels by mutant isocitrate dehydrogenase 1/2 (IDH1/2) enzymes, was reported as an oncometabolite. We show here that R-2HG also exerts a broad anti-leukemic activity in vitro and in vivo by inhibiting leukemia cell proliferation/viability and by promoting cell-cycle arrest and apoptosis. Mechanistically, R-2HG inhibits fat mass and obesity-associated protein (FTO) activity, thereby increasing global N6-methyladenosine (m6A) RNA modification in R-2HG-sensitive leukemia cells, which in turn decreases the stability of MYC/CEBPA transcripts, leading to the suppression of relevant pathways. Ectopically expressed mutant IDH1 and S-2HG recapitulate the effects of R-2HG. High levels of FTO sensitize leukemic cells to R-2HG, whereas hyperactivation of MYC signaling confers resistance that can be reversed by the inhibition of MYC signaling. R-2HG also displays anti-tumor activity in glioma. Collectively, while R-2HG accumulated in IDH1/2 mutant cancers contributes to cancer initiation, our work demonstrates anti-tumor effects of 2HG in inhibiting proliferation/survival of FTO-high cancer cells via targeting FTO/m6A/MYC/CEBPA signaling.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Glutaratos/farmacologia , Leucemia/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Adenosina/análogos & derivados , Adenosina/metabolismo , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Animais , Antineoplásicos/uso terapêutico , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Linhagem Celular Tumoral , Glutaratos/uso terapêutico , Células HEK293 , Humanos , Células Jurkat , Camundongos , Proteínas Proto-Oncogênicas c-myc/metabolismo , Processamento Pós-Transcricional do RNA
3.
Mol Cell ; 84(3): 596-610.e6, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38215754

RESUMO

Although DNA N6-methyl-deoxyadenosine (6mA) is abundant in bacteria and protists, its presence and function in mammalian genomes have been less clear. We present Direct-Read 6mA sequencing (DR-6mA-seq), an antibody-independent method, to measure 6mA at base resolution. DR-6mA-seq employs a unique mutation-based strategy to reveal 6mA sites as misincorporation signatures without any chemical or enzymatic modulation of 6mA. We validated DR-6mA-seq through the successful mapping of the well-characterized G(6mA)TC motif in the E. coli DNA. As expected, when applying DR-6mA-seq to mammalian systems, we found that genomic DNA (gDNA) 6mA abundance is generally low in most mammalian tissues and cells; however, we did observe distinct gDNA 6mA sites in mouse testis and glioblastoma cells. DR-6mA-seq provides an enabling tool to detect 6mA at single-base resolution for a comprehensive understanding of DNA 6mA in eukaryotes.


Assuntos
Metilação de DNA , Escherichia coli , Animais , Camundongos , Escherichia coli/genética , Genoma/genética , DNA/metabolismo , Eucariotos/genética , Desoxiadenosinas/genética , Mamíferos/metabolismo
4.
Mol Cell ; 78(3): 382-395.e8, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32183942

RESUMO

N6-Methyldeoxyadenosine (6mA) has recently been shown to exist and play regulatory roles in eukaryotic genomic DNA (gDNA). However, the biological functions of 6mA in mammals have yet to be adequately explored, largely due to its low abundance in most mammalian genomes. Here, we report that mammalian mitochondrial DNA (mtDNA) is enriched for 6mA. The level of 6mA in HepG2 mtDNA is at least 1,300-fold higher than that in gDNA under normal growth conditions, corresponding to approximately four 6mA modifications on each mtDNA molecule. METTL4, a putative mammalian methyltransferase, can mediate mtDNA 6mA methylation, which contributes to attenuated mtDNA transcription and a reduced mtDNA copy number. Mechanistically, the presence of 6mA could repress DNA binding and bending by mitochondrial transcription factor (TFAM). Under hypoxia, the 6mA level in mtDNA could be further elevated, suggesting regulatory roles for 6mA in mitochondrial stress response. Our study reveals DNA 6mA as a regulatory mark in mammalian mtDNA.


Assuntos
DNA Mitocondrial/metabolismo , Desoxiadenosinas/metabolismo , Metiltransferases/metabolismo , Animais , Metilação de DNA , DNA Mitocondrial/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Desoxiadenosinas/genética , Regulação da Expressão Gênica , Células Hep G2 , Humanos , Hipóxia/genética , Metiltransferases/genética , Camundongos Endogâmicos C57BL , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
5.
Nucleic Acids Res ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850159

RESUMO

Genomic instability is one of the hallmarks of cancer. While loss of histone demethylase KDM6A increases the risk of tumorigenesis, its specific role in maintaining genomic stability remains poorly understood. Here, we propose a mechanism in which KDM6A maintains genomic stability independently on its demethylase activity. This occurs through its interaction with SND1, resulting in the establishment of a protective chromatin state that prevents replication fork collapse by recruiting of RPA and Ku70 to nascent DNA strand. Notably, KDM6A-SND1 interaction is up-regulated by KDM6A SUMOylation, while KDM6AK90A mutation almost abolish the interaction. Loss of KDM6A or SND1 leads to increased enrichment of H3K9ac and H4K8ac but attenuates the enrichment of Ku70 and H3K4me3 at nascent DNA strand. This subsequently results in enhanced cellular sensitivity to genotoxins and genomic instability. Consistent with these findings, knockdown of KDM6A and SND1 in esophageal squamous cell carcinoma (ESCC) cells increases genotoxin sensitivity. Intriguingly, KDM6A H101D & P110S, N1156T and D1216N mutations identified in ESCC patients promote genotoxin resistance via increased SND1 association. Our finding provides novel insights into the pivotal role of KDM6A-SND1 in genomic stability and chemoresistance, implying that targeting KDM6A and/or its interaction with SND1 may be a promising strategy to overcome the chemoresistance.

6.
Development ; 149(3)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35043944

RESUMO

Establishment of a healthy ovarian reserve is contingent upon numerous regulatory pathways during embryogenesis. Previously, mice lacking TBP-associated factor 4b (Taf4b) were shown to exhibit a diminished ovarian reserve. However, potential oocyte-intrinsic functions of TAF4b have not been examined. Here, we use a combination of gene expression profiling and chromatin mapping to characterize TAF4b-dependent gene regulatory networks in mouse oocytes. We find that Taf4b-deficient oocytes display inappropriate expression of meiotic, chromatin modification/organization, and X-linked genes. Furthermore, dysregulated genes in Taf4b-deficient oocytes exhibit an unexpected amount of overlap with dysregulated genes in oocytes from XO female mice, a mouse model of Turner Syndrome. Using Cleavage Under Targets and Release Using Nuclease (CUT&RUN), we observed TAF4b enrichment at genes involved in chromatin remodeling and DNA repair, some of which are differentially expressed in Taf4b-deficient oocytes. Interestingly, TAF4b target genes were enriched for Sp/Klf family and NFY target motifs rather than TATA-box motifs, suggesting an alternative mode of promoter interaction. Together, our data connect several gene regulatory nodes that contribute to the precise development of the mammalian ovarian reserve.


Assuntos
Redes Reguladoras de Genes/genética , Oogênese , Fatores Associados à Proteína de Ligação a TATA/genética , Fator de Transcrição TFIID/genética , Animais , Reparo do DNA , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Feminino , Células Germinativas/citologia , Células Germinativas/metabolismo , Meiose , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oócitos/citologia , Oócitos/metabolismo , Regiões Promotoras Genéticas , Fatores Associados à Proteína de Ligação a TATA/deficiência , Fatores Associados à Proteína de Ligação a TATA/metabolismo , Fator de Transcrição TFIID/deficiência , Fator de Transcrição TFIID/metabolismo , Cromossomo X/genética , Cromossomo X/metabolismo
7.
Nat Chem Biol ; 19(11): 1384-1393, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37400536

RESUMO

Compact CRISPR-Cas systems offer versatile treatment options for genetic disorders, but their application is often limited by modest gene-editing activity. Here we present enAsCas12f, an engineered RNA-guided DNA endonuclease up to 11.3-fold more potent than its parent protein, AsCas12f, and one-third of the size of SpCas9. enAsCas12f shows higher DNA cleavage activity than wild-type AsCas12f in vitro and functions broadly in human cells, delivering up to 69.8% insertions and deletions at user-specified genomic loci. Minimal off-target editing is observed with enAsCas12f, suggesting that boosted on-target activity does not impair genome-wide specificity. We determine the cryo-electron microscopy (cryo-EM) structure of the AsCas12f-sgRNA-DNA complex at a resolution of 2.9 Å, which reveals dimerization-mediated substrate recognition and cleavage. Structure-guided single guide RNA (sgRNA) engineering leads to sgRNA-v2, which is 33% shorter than the full-length sgRNA, but with on par activity. Together, the engineered hypercompact AsCas12f system enables robust and faithful gene editing in mammalian cells.


Assuntos
Edição de Genes , RNA Guia de Sistemas CRISPR-Cas , Animais , Humanos , Microscopia Crioeletrônica , Sistemas CRISPR-Cas/genética , DNA/química , Mamíferos/genética
8.
Nature ; 567(7748): 414-419, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30867593

RESUMO

DNA and histone modifications have notable effects on gene expression1. Being the most prevalent internal modification in mRNA, the N6-methyladenosine (m6A) mRNA modification is as an important post-transcriptional mechanism of gene regulation2-4 and has crucial roles in various normal and pathological processes5-12. However, it is unclear how m6A is specifically and dynamically deposited in the transcriptome. Here we report that histone H3 trimethylation at Lys36 (H3K36me3), a marker for transcription elongation, guides m6A deposition globally. We show that m6A modifications are enriched in the vicinity of H3K36me3 peaks, and are reduced globally when cellular H3K36me3 is depleted. Mechanistically, H3K36me3 is recognized and bound directly by METTL14, a crucial component of the m6A methyltransferase complex (MTC), which in turn facilitates the binding of the m6A MTC to adjacent RNA polymerase II, thereby delivering the m6A MTC to actively transcribed nascent RNAs to deposit m6A co-transcriptionally. In mouse embryonic stem cells, phenocopying METTL14 knockdown, H3K36me3 depletion also markedly reduces m6A abundance transcriptome-wide and in pluripotency transcripts, resulting in increased cell stemness. Collectively, our studies reveal the important roles of H3K36me3 and METTL14 in determining specific and dynamic deposition of m6A in mRNA, and uncover another layer of gene expression regulation that involves crosstalk between histone modification and RNA methylation.


Assuntos
Adenosina/análogos & derivados , Histonas/química , Histonas/metabolismo , Lisina/metabolismo , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Transcrição Gênica , Adenosina/metabolismo , Animais , Diferenciação Celular , Linhagem Celular , Células-Tronco Embrionárias/metabolismo , Humanos , Lisina/química , Metilação , Metiltransferases/deficiência , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos , RNA Polimerase II/metabolismo , Elongação da Transcrição Genética , Transcriptoma/genética
9.
Proc Natl Acad Sci U S A ; 119(33): e2209164119, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35878056

RESUMO

Voltage-gated sodium (Nav) channel Nav1.7 has been targeted for the development of nonaddictive pain killers. Structures of Nav1.7 in distinct functional states will offer an advanced mechanistic understanding and aid drug discovery. Here we report the cryoelectron microscopy analysis of a human Nav1.7 variant that, with 11 rationally introduced point mutations, has a markedly right-shifted activation voltage curve with V1/2 reaching 69 mV. The voltage-sensing domain in the first repeat (VSDI) in a 2.7-Å resolution structure displays a completely down (deactivated) conformation. Compared to the structure of WT Nav1.7, three gating charge (GC) residues in VSDI are transferred to the cytosolic side through a combination of helix unwinding and spiral sliding of S4I and ∼20° domain rotation. A conserved WNФФD motif on the cytoplasmic end of S3I stabilizes the down conformation of VSDI. One GC residue is transferred in VSDII mainly through helix sliding. Accompanying GC transfer in VSDI and VSDII, rearrangement and contraction of the intracellular gate is achieved through concerted movements of adjacent segments, including S4-5I, S4-5II, S5II, and all S6 segments. Our studies provide important insight into the electromechanical coupling mechanism of the single-chain voltage-gated ion channels and afford molecular interpretations for a number of pain-associated mutations whose pathogenic mechanism cannot be revealed from previously reported Nav structures.


Assuntos
Canal de Sódio Disparado por Voltagem NAV1.7 , Dor , Motivos de Aminoácidos , Microscopia Crioeletrônica , Humanos , Mutação , Canal de Sódio Disparado por Voltagem NAV1.7/química , Canal de Sódio Disparado por Voltagem NAV1.7/genética , Canal de Sódio Disparado por Voltagem NAV1.7/metabolismo , Dor/genética , Domínios Proteicos , Rotação
10.
Proc Natl Acad Sci U S A ; 119(30): e2208211119, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35858452

RESUMO

The dorsal root ganglia-localized voltage-gated sodium (Nav) channel Nav1.8 represents a promising target for developing next-generation analgesics. A prominent characteristic of Nav1.8 is the requirement of more depolarized membrane potential for activation. Here we present the cryogenic electron microscopy structures of human Nav1.8 alone and bound to a selective pore blocker, A-803467, at overall resolutions of 2.7 to 3.2 Å. The first voltage-sensing domain (VSDI) displays three different conformations. Structure-guided mutagenesis identified the extracellular interface between VSDI and the pore domain (PD) to be a determinant for the high-voltage dependence of activation. A-803467 was clearly resolved in the central cavity of the PD, clenching S6IV. Our structure-guided functional characterizations show that two nonligand binding residues, Thr397 on S6I and Gly1406 on S6III, allosterically modulate the channel's sensitivity to A-803467. Comparison of available structures of human Nav channels suggests the extracellular loop region to be a potential site for developing subtype-specific pore-blocking biologics.


Assuntos
Compostos de Anilina , Furanos , Canal de Sódio Disparado por Voltagem NAV1.7 , Bloqueadores do Canal de Sódio Disparado por Voltagem , Regulação Alostérica , Compostos de Anilina/química , Compostos de Anilina/farmacologia , Microscopia Crioeletrônica , Furanos/química , Furanos/farmacologia , Humanos , Potenciais da Membrana , Canal de Sódio Disparado por Voltagem NAV1.7/química , Domínios Proteicos , Bloqueadores do Canal de Sódio Disparado por Voltagem/química , Bloqueadores do Canal de Sódio Disparado por Voltagem/farmacologia
11.
BMC Biol ; 22(1): 33, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38331785

RESUMO

BACKGROUND: Ribosomal protein SA (RPSA) of human brain microvascular endothelial cells (HBMECs) can transfer from the cytosol to the cell surface and act as a receptor for some pathogens, including Streptococcus suis serotype 2 (SS2), a zoonotic pathogen causing meningitis in pigs and humans. We previously reported that SS2 virulence factor enolase (ENO) binds to RPSA on the cell surface of HBMECs and induces apoptosis. However, the mechanism that activates RPSA translocation to the cell surface and induces ENO-mediated HBMEC apoptosis is unclear. RESULTS: Here, we show that RPSA localization and condensation on the host cell surface depend on its internally disordered region (IDR). ENO binds to the IDR of RPSA and promotes its interaction with RPSA and vimentin (VIM), which is significantly suppressed after 1,6-Hexanediol (1,6-Hex, a widely used tool to disrupt phase separation) treatment, indicating that ENO incorporation and thus the concentration of RPSA/VIM complexes via co-condensation. Furthermore, increasing intracellular calcium ions (Ca2+) in response to SS2 infection further facilitates the liquid-like condensation of RPSA and aggravates ENO-induced HBMEC cell apoptosis. CONCLUSIONS: Together, our study provides a previously underappreciated molecular mechanism illuminating that ENO-induced RPSA condensation activates the migration of RPSA to the bacterial cell surface and stimulates SS2-infected HBMEC death and, potentially, disease progression. This study offers a fresh avenue for investigation into the mechanism by which other harmful bacteria infect hosts via cell surfaces' RPSA.


Assuntos
Infecções Estreptocócicas , Streptococcus suis , Humanos , Animais , Suínos , Células Endoteliais/metabolismo , Sorogrupo , Fosfopiruvato Hidratase/genética , Fosfopiruvato Hidratase/metabolismo , Encéfalo/metabolismo , Apoptose , Proteínas Ribossômicas/metabolismo , Infecções Estreptocócicas/metabolismo , Infecções Estreptocócicas/microbiologia
12.
Nano Lett ; 24(15): 4641-4648, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38579120

RESUMO

The intrinsic properties of materials play a substantial role in light-matter interactions, impacting both bulk metals and nanostructures. While plasmonic nanostructures exhibit strong interactions with photons via plasmon resonances, achieving efficient light absorption/scattering in other transition metals remains a challenge, impeding various applications related to optoelectronics, chemistry, and energy harvesting. Here, we propose a universal strategy to enhance light-matter interaction, through introducing voids onto the surface of metallic nanoparticles. This strategy spans nine metals including those traditionally considered optically inactive. The absorption cross section of void-filled nanoparticles surpasses the value of plasmonic (Ag/Au) counterparts with tunable resonance peaks across a broad spectral range. Notably, this enhancement is achieved under arbitrary polarizations and varied particle sizes and in the presence of geometric disorder, highlighting the universal adaptability. Our strategy holds promise for inspiring emerging devices in photocatalysis, bioimaging, optical sensing, and beyond, particularly when metals other than gold or silver are preferred.

13.
Am J Physiol Cell Physiol ; 326(2): C400-C413, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38105755

RESUMO

Kidney fibrosis is a prominent pathological feature of hypertensive kidney diseases (HKD). Recent studies have highlighted the role of ubiquitinating/deubiquitinating protein modification in kidney pathophysiology. Ovarian tumor domain-containing protein 6 A (OTUD6A) is a deubiquitinating enzyme involved in tumor progression. However, its role in kidney pathophysiology remains elusive. We aimed to investigate the role and underlying mechanism of OTUD6A during kidney fibrosis in HKD. The results revealed higher OTUD6A expression in kidney tissues of nephropathy patients and mice with chronic angiotensin II (Ang II) administration than that from the control ones. OTUD6A was mainly located in tubular epithelial cells. Moreover, OTUD6A deficiency significantly protected mice against Ang II-induced kidney dysfunction and fibrosis. Also, knocking OTUD6A down suppressed Ang II-induced fibrosis in cultured tubular epithelial cells, whereas overexpression of OTUD6A enhanced fibrogenic responses. Mechanistically, OTUD6A bounded to signal transducer and activator of transcription 3 (STAT3) and removed K63-linked-ubiquitin chains to promote STAT3 phosphorylation at tyrosine 705 position and nuclear translocation, which then induced profibrotic gene transcription in epithelial cells. These studies identified STAT3 as a direct substrate of OTUD6A and highlighted the pivotal role of OTUD6A in Ang II-induced kidney injury, indicating OTUD6A as a potential therapeutic target for HKD.NEW & NOTEWORTHY Ovarian tumor domain-containing protein 6 A (OTUD6A) knockout mice are protected against angiotensin II-induced kidney dysfunction and fibrosis. OTUD6A promotes pathological kidney remodeling and dysfunction by deubiquitinating signal transducer and activator of transcription 3 (STAT3). OTUD6A binds to and removes K63-linked-ubiquitin chains of STAT3 to promote its phosphorylation and activation, and subsequently enhances kidney fibrosis.


Assuntos
Hipertensão Renal , Nefrite , Neoplasias Ovarianas , Humanos , Camundongos , Animais , Feminino , Angiotensina II/farmacologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Rim/metabolismo , Hipertensão Renal/metabolismo , Hipertensão Renal/patologia , Células Epiteliais/metabolismo , Fibrose , Neoplasias Ovarianas/metabolismo , Ubiquitinas/metabolismo , Camundongos Endogâmicos C57BL
14.
BMC Genomics ; 25(1): 91, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253995

RESUMO

BACKGROUND: Spodoptera litura is a harmful pest that feeds on more than 80 species of plants, and can be infected and killed by Spodoptera litura nucleopolyhedrovirus (SpltNPV). SpltNPV-C3 is a type C SpltNPV clone, that was observed and collected in Japan. Compared with type A or type B SpltNPVs, SpltNPV-C3 can cause the rapid mortality of S. litura larvae. METHODS: In this study, occlusion bodies (OBs) and occlusion-derived viruses (ODVs) of SpltNPV-C3 were purified, and OBs were observed by scanning electron microscopy (SEM). ODVs were observed under a transmission electron microscope (TEM). RESULTS: Both OBs and ODVs exhibit morphological characteristics typical of nucleopolyhedroviruses (NPVs).The genome of SpltNPV-C3 was sequenced and analyzed; the total length was 148,634 bp (GenBank accession 780,426,which was submitted as SpltNPV-II), with a G + C content of 45%. A total of 149 predicted ORFs were found. A phylogenetic tree of 90 baculoviruses was constructed based on core baculovirus genes. LC‒MS/MS was used to analyze the proteins of SpltNPV-C3; 34 proteins were found in the purified ODVs, 15 of which were core proteins. The structure of the complexes formed by per os infectivity factors 1, 2, 3 and 4 (PIF-1, PIF-2, PIF-3 and PIF-4) was predicted with the help of the AlphaFold multimer tool and predicted conserved sequences in PIF-3. SpltNPV-C3 is a valuable species because of its virulence, and the analysis of its genome and proteins in this research will be beneficial for pest control efforts.


Assuntos
Nucleopoliedrovírus , Proteoma , Animais , Nucleopoliedrovírus/genética , Spodoptera , Cromatografia Líquida , Filogenia , Espectrometria de Massas em Tandem , Baculoviridae
15.
Hum Mol Genet ; 31(23): 4094-4106, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-35848890

RESUMO

High-throughput circular RNA (circRNA) sequencing identified circRNA_001678 (circ_001678) as an upregulated circRNA in non-small cell lung cancer (NSCLC) tissues. Hence, the current study sought to investigate the function and the underlying mechanism of circRNA_001678 in immune escape of NSCLC. Briefly, commercially purchased NSCLC cell lines were adopted for in vitro experiment to evaluate the effects of circ_001678 over-expression or knockdown on cell biological functions, including proliferation, migration and invasive abilities. In addition, the effects of circ_001678 on the in vivo tumorigenicity ability were evaluated for verification. Accordingly, we uncovered that circ_001678 over-expression augmented NSCLC progression in vitro and enhanced tumorigenicity ability in vivo. The interaction between circ_001678 and miR-326 predicted online was verified by means of luciferase and RNA pull-down assays. Furthermore, circ_001678 could sponge miR-326 to up-regulate ZEB1. On the other hand, the tumor-promoting effects of circ_001678 could be inhibited by anti-PD-L1/PD-1 treatment. Mechanistically, circ_001678 led to the activation of the PD-1/PD-L1 pathway to promote CD8+ T cell apoptosis, thereby inducing NSCLC cell immune escape via regulation of the miR-326/ZEB1 axis. To conclude, our findings revealed that circ_001678 sponges miR-326 to up-regulate ZEB1 expression and induce the PD-1/PD-L1 pathway-dependent immune escape, thereby promoting the malignant progression of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Receptor de Morte Celular Programada 1/genética , RNA Circular/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , Proliferação de Células/genética , Linhagem Celular Tumoral , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética
16.
Thorax ; 79(5): 448-456, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38182426

RESUMO

BACKGROUND: Body composition might influence lung function and asthma in children, but its longitudinal relations are unclear. We aimed to identify critical periods for body composition changes during childhood and adolescence in relation to respiratory outcomes in adolescents. METHODS: In a population-based prospective cohort study, we measured body mass index, fat mass index (FMI), lean mass index (LMI) and the ratio of android fat mass divided by gynoid fat mass (A/G ratio) by dual-energy X-ray absorptiometry at 6, 10 and 13 years. At 13 years, lung function was measured by spirometry, and current asthma was assessed by questionnaire. RESULTS: Most prominently and consistently, higher FMI and A/G ratio at age 13 years were associated with lower forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) and forced expiratory flow after exhaling 75% of FVC (FEF75) (range Z-score difference -0.13 (95% CI -0.16 to -0.10) to -0.08 (95% CI -0.11 to -0.05) per SD score increase), and higher LMI at all ages was associated with higher FEF75 (range Z-score difference 0.05 (95% CI 0.01 to 0.08) to 0.09 (95% CI 0.06 to 0.13)). Between the ages of 6 and 13 years, normal to high FMI and A/G ratio were associated with lower FEV1/FVC and FEF75 (range Z-score difference -0.20 (95% CI -0.30 to -0.10) to -0.17 (95% CI -0.28 to -0.06)) and high to high LMI with higher FEF75 (range Z-score difference0.32 (95% CI 0.23 to 0.41)). Body composition changes were not associated with asthma. CONCLUSION: Adolescents with higher total and abdominal fat indices may have impaired lung function, while those with a higher lean mass during childhood and adolescence may have better small airway function. Public health measures should focus on a healthy body composition in adolescents to minimise respiratory morbidity.


Assuntos
Asma , Criança , Adolescente , Humanos , Estudos Prospectivos , Composição Corporal , Volume Expiratório Forçado , Capacidade Vital , Índice de Massa Corporal , Pulmão
17.
Gastroenterology ; 164(3): 407-423.e17, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36574521

RESUMO

BACKGROUND & AIMS: Lack of thorough knowledge about the complicated immune microenvironment (IM) within a variety of liver metastases (LMs) leads to inappropriate treatment and unsatisfactory prognosis. We aimed to characterize IM subtypes and investigate potential mechanisms in LMs. METHODS: Mass cytometry was applied to characterize immune landscape of a primary liver cancers and liver metastases cohort. Transcriptomic and whole-exome sequencing were used to explore potential mechanisms across distinct IM subtypes. Single-cell transcriptomic sequencing, multiplex fluorescent immunohistochemistry, cell culture, mouse model, Western blot, quantitative polymerase chain reaction, and immunohistochemistry were used for validation. RESULTS: Five IM subtypes were revealed in 100 LMs and 50 primary liver cancers. Patients featured terminally exhausted (IM1) or rare T-cell-inflamed (IM2 and IM3) immune characteristics showed worse outcome. Increased intratumor heterogeneity, enriched somatic TP53, KRAS, APC, and PIK3CA mutations and hyperactivated hypoxia signaling accounted for the formation of vicious subtypes. SLC2A1 promoted immune suppression and desert via increasing proportion of Spp1+ macrophages and their inhibitory interactions with T cells in liver metastatic lesions. Furthermore, SLC2A1 promoted immune escape and LM through inducing regulatory T cells, including regulatory T cells and LAG3+CD4+ T cells in primary colorectal cancer. CONCLUSIONS: The study provided integrated multi-omics landscape of LM, uncovering potential mechanisms for vicious IM subtypes and confirming the roles of SLC2A1 in regulating tumor microenvironment remodeling in both primary tumor and LM lesions.


Assuntos
Neoplasias Hepáticas , Multiômica , Animais , Camundongos , Mutação , Neoplasias Hepáticas/patologia , Sequenciamento do Exoma , Microambiente Tumoral
18.
Cancer Immunol Immunother ; 73(8): 159, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850359

RESUMO

BACKGROUND: Although, immune checkpoint inhibitors (ICIs) have been widely applied in the therapy of malignant tumors, the efficacy and safety of ICIs in patients with tumors and pre-existing CAD, especially chronic coronary syndromes (CCS) or their risk factors (CRF), is not well identified. METHODS: This was a nationwide multicenter observational study that enrolled participants who diagnosed with solid tumors and received ICIs therapy. The main efficacy indicators were progression-free survival (PFS) and overall survival (OS), followed by objective response rate (ORR) and disease control rate (DCR). Safety was assessed by describing treatment-related adverse events (TRAEs) during ICIs therapy evaluated by the Common Terminology Criteria for Adverse Events 5.0 (CTCAE 5.0). RESULTS: In the current research, we retrospectively analyzed the data of 551 patients diagnosed with solid tumors and received ICIs therapy, and these patients were divided into CCS/CRF group and non-CCS/CRF group. Patients with CCS/CRF had more favorable PFS and OS than patients without CCS/CRF (P < 0.001) and the pre-existing CCS/CRF was a protective factor for survival. The ORR (51.8% vs. 39.1%) and DCR (95.8% vs. 89.2%) were higher in CCS/CRF group than in non-CCS/CRF group (P = 0.003, P = 0.006). In this study, there was no significant difference in treatment-related adverse events (TRAEs), including immune-related adverse events (irAEs), between the two groups. CONCLUSIONS: We concluded that ICIs appear to have better efficacy in malignant solid tumor patients with pre-existing CCS/CRF and are not accompanied by more serious irAEs.


Assuntos
Inibidores de Checkpoint Imunológico , Neoplasias , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Inibidores de Checkpoint Imunológico/uso terapêutico , Feminino , Masculino , Neoplasias/tratamento farmacológico , Neoplasias/complicações , Neoplasias/imunologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Fatores de Risco , Adulto , Idoso de 80 Anos ou mais , Estudos de Coortes
19.
Small ; : e2309857, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38258604

RESUMO

Currently, artificial neural networks (ANNs) based on memristors are limited to recognizing static images of objects when simulating human visual system, preventing them from performing high-dimensional information perception, and achieving more complex biomimetic functions is subject to certain limitations. In this work, indium gallium zinc oxide (IGZO)/tungsten oxide (WO3-x )-heterostructured artificial optoelectronic synaptic devices mimicking image segmentation and motion capture exhibiting high-performance optoelectronic synaptic responses are proposed and demonstrated. Upon electrical and optical stimulations, the device shows a variety of fundamental and advanced electrical and optical synaptic plasticity. Most importantly, outstanding and repeatable linear synaptic weight changes are attained by the developed memristor. By taking advantage of the notable linear synaptic weight changes, ANNs have been constructed and successfully utilized to demonstrate two applications in the field of computer vision, including image segmentation and object tracking. The accuracy attained by the memristor-based ANNs is similar to that of the computer algorithms, while its power has been significantly reduced by 105 orders of magnitude. With successful emulations of the human brain reactions when observing objects, the demonstrated memristor and related ANNs can be effectively utilized in constructing artificial optoelectronic synaptic devices and show promising potential in emulating human visual perception.

20.
Small ; : e2401150, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38506563

RESUMO

The unique optical and electrical properties of graphene-based heterojunctions make them significant for artificial synaptic devices, promoting the advancement of biomimetic vision systems. However, mass production and integration of device arrays are necessary for visual imaging, which is still challenging due to the difficulty in direct growth of wafer-scale graphene patterns. Here, a novel strategy is proposed using photosensitive polymer as a solid carbon source for in situ growth of patterned graphene on diverse substrates. The growth mechanism during high-temperature annealing is elucidated, leading to wafer-scale graphene patterns with exceptional uniformity, ideal crystalline quality, and precise control over layer number by eliminating the release of volatile from oxygen-containing resin. The growth strategy enables the fabrication of two-inch optoelectronic artificial synaptic device array based on graphene/n-AlGaN heterojunction, which emulates key functionalities of biological synapses, including short-term plasticity, long-term plasticity, and spike-rate-dependent plasticity. Moreover, the mimicry of visual learning in the human brain is attributed to the regulation of excitatory and inhibitory post-synapse currents, following a learning rule that prioritizes initial recognition before memory formation. The duration of long-term memory reaches 10 min. The in situ growth strategy for patterned graphene represents the novelty for fabricating fundamental hardware of an artificial neuromorphic system.

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