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1.
Annu Rev Cell Dev Biol ; 35: 407-431, 2019 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-31403819

RESUMO

A large and significant portion of eukaryotic transcriptomes consists of noncoding RNAs (ncRNAs) that have minimal or no protein-coding capacity but are functional. Diverse ncRNAs, including both small RNAs and long ncRNAs (lncRNAs), play essential regulatory roles in almost all biological processes by modulating gene expression at the transcriptional and posttranscriptional levels. In this review, we summarize the current knowledge of plant small RNAs and lncRNAs, with a focus on their biogenesis, modes of action, local and systemic movement, and functions at the nexus of plant development and environmental responses. The complex connections among small RNAs, lncRNAs, and small peptides in plants are also discussed, along with the challenges of identifying and investigating new classes of ncRNAs.


Assuntos
Desenvolvimento Vegetal/genética , Plantas/genética , RNA Longo não Codificante/metabolismo , RNA de Plantas/metabolismo , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , RNA Longo não Codificante/genética , RNA de Plantas/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo
2.
Cell ; 153(3): 562-74, 2013 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-23622241

RESUMO

Translation inhibition is a major but poorly understood mode of action of microRNAs (miRNAs) in plants and animals. In particular, the subcellular location where this process takes place is unknown. Here, we show that the translation inhibition, but not the mRNA cleavage activity, of Arabidopsis miRNAs requires ALTERED MERISTEM PROGRAM1 (AMP1). AMP1 encodes an integral membrane protein associated with endoplasmic reticulum (ER) and ARGONAUTE1, the miRNA effector and a peripheral ER membrane protein. Large differences in polysome association of miRNA target RNAs are found between wild-type and the amp1 mutant for membrane-bound, but not total, polysomes. This, together with AMP1-independent recruitment of miRNA target transcripts to membrane fractions, shows that miRNAs inhibit the translation of target RNAs on the ER. This study demonstrates that translation inhibition is an important activity of plant miRNAs, reveals the subcellular location of this activity, and uncovers a previously unknown function of the ER.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Carboxipeptidases/metabolismo , Retículo Endoplasmático/metabolismo , MicroRNAs/metabolismo , RNA de Plantas/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Carboxipeptidases/genética , Pleiotropia Genética , Mutação , Polirribossomos/metabolismo , Biossíntese de Proteínas , RNA Mensageiro/metabolismo
3.
Hum Mol Genet ; 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39216871

RESUMO

This study explored the roles of methionine adenosyltransferase 2A (MAT2A) and tripartite motif containing 25 (TRIM25) in the progression of thoracic aortic aneurysm (TAA). The TAA model was established based on the ß-aminopropionitrile method. The effects of MAT2A on thoracic aortic lesions and molecular levels were analyzed by several pathological staining assays (hematoxylin-eosin, Verhoeff-Van Gieson, TUNEL) and molecular biology experiments (qRT-PCR, Western blot). Angiotensin II (Ang-II) was used to induce injury in vascular smooth muscle cells (VSMCs) in vitro. The effects of MAT2A, shMAT2A, shTRIM25 and/or Wnt inhibitor (IWR-1) on the viability, apoptosis and protein expressions of VSMCs were examined by CCK-8, Annexin V-FITC/PI and Western blot assays. In TAA mice, overexpression of MAT2A alleviated thoracic aortic injury, inhibited the aberrant expressions of aortic contractile proteins and dedifferentiation markers, and blocked the activation of Wnt/ß-catenin pathway. In Ang-II-induced VSMCs, up-regulation of MAT2A increased cellular activity and repressed the expression of ß-catenin protein. TRIM25 knockdown promoted activity of VSMCs, inhibited apoptosis, and blocked the Wnt/ß-catenin pathway activation by binding to MAT2A. IWR-1 partially counteracted the regulatory effects of shMAT2A. Collectively, TRIM25 destabilises the mRNA of MAT2A to activate Wnt/ß-catenin signaling and ultimately exacerbate TAA injury.

4.
EMBO Rep ; 25(2): 770-795, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38182816

RESUMO

DExD/H-box helicases are crucial regulators of RNA metabolism and antiviral innate immune responses; however, their role in bacteria-induced inflammation remains unclear. Here, we report that DDX5 interacts with METTL3 and METTL14 to form an m6A writing complex, which adds N6-methyladenosine to transcripts of toll-like receptor (TLR) 2 and TLR4, promoting their decay via YTHDF2-mediated RNA degradation, resulting in reduced expression of TLR2/4. Upon bacterial infection, DDX5 is recruited to Hrd1 at the endoplasmic reticulum in an MyD88-dependent manner and is degraded by the ubiquitin-proteasome pathway. This process disrupts the DDX5 m6A writing complex and halts m6A modification as well as degradation of TLR2/4 mRNAs, thereby promoting the expression of TLR2 and TLR4 and downstream NF-κB activation. The role of DDX5 in regulating inflammation is also validated in vivo, as DDX5- and METTL3-KO mice exhibit enhanced expression of inflammatory cytokines. Our findings show that DDX5 acts as a molecular switch to regulate inflammation during bacterial infection and shed light on mechanisms of quiescent inflammation during homeostasis.


Assuntos
Adenina , Infecções Bacterianas , Receptor 2 Toll-Like , Animais , Camundongos , Adenina/análogos & derivados , Inflamação/genética , Metiltransferases/genética , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética
5.
Nucleic Acids Res ; 52(10): 5698-5719, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38587186

RESUMO

AT-rich interaction domain protein 1A (ARID1A), a SWI/SNF chromatin remodeling complex subunit, is frequently mutated across various cancer entities. Loss of ARID1A leads to DNA repair defects. Here, we show that ARID1A plays epigenetic roles to promote both DNA double-strand breaks (DSBs) repair pathways, non-homologous end-joining (NHEJ) and homologous recombination (HR). ARID1A is accumulated at DSBs after DNA damage and regulates chromatin loops formation by recruiting RAD21 and CTCF to DSBs. Simultaneously, ARID1A facilitates transcription silencing at DSBs in transcriptionally active chromatin by recruiting HDAC1 and RSF1 to control the distribution of activating histone marks, chromatin accessibility, and eviction of RNAPII. ARID1A depletion resulted in enhanced accumulation of micronuclei, activation of cGAS-STING pathway, and an increased expression of immunomodulatory cytokines upon ionizing radiation. Furthermore, low ARID1A expression in cancer patients receiving radiotherapy was associated with higher infiltration of several immune cells. The high mutation rate of ARID1A in various cancer types highlights its clinical relevance as a promising biomarker that correlates with the level of immune regulatory cytokines and estimates the levels of tumor-infiltrating immune cells, which can predict the response to the combination of radio- and immunotherapy.


Assuntos
Cromatina , Reparo do DNA , Proteínas de Ligação a DNA , Imunidade , Fatores de Transcrição , Humanos , Linhagem Celular Tumoral , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina/genética , Quebras de DNA de Cadeia Dupla , Reparo do DNA/genética , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Histona Desacetilase 1/genética , Histona Desacetilase 1/metabolismo , Recombinação Homóloga/genética , Imunidade/genética , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/imunologia , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Transativadores , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
6.
Proc Natl Acad Sci U S A ; 120(45): e2205463120, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37917793

RESUMO

Zero-knowledge proof (ZKP) is a fundamental cryptographic primitive that allows a prover to convince a verifier of the validity of a statement without leaking any further information. As an efficient variant of ZKP, noninteractive zero-knowledge proof (NIZKP) adopting the Fiat-Shamir heuristic is essential to a wide spectrum of applications, such as federated learning, blockchain, and social networks. However, the heuristic is typically built upon the random oracle model that makes ideal assumptions about hash functions, which does not hold in reality and thus undermines the security of the protocol. Here, we present a quantum solution to the problem. Instead of resorting to a random oracle model, we implement a quantum randomness service. This service generates random numbers certified by the loophole-free Bell test and delivers them with postquantum cryptography (PQC) authentication. By employing this service, we conceive and implement NIZKP of the three-coloring problem. By bridging together three prominent research themes, quantum nonlocality, PQC, and ZKP, we anticipate this work to inspire more innovative applications that combine quantum information science and the cryptography field.

7.
J Neurosci ; 44(34)2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39019613

RESUMO

Although anesthesia provides favorable conditions for surgical procedures, recent studies have revealed that the brain remains active in processing noxious signals even during anesthesia. However, whether and how these responses affect the anesthesia effect remains unclear. The ventrolateral periaqueductal gray (vlPAG), a crucial hub for pain regulation, also plays an essential role in controlling general anesthesia. Hence, it was hypothesized that the vlPAG may be involved in the regulation of general anesthesia by noxious stimuli. Here, we found that acute noxious stimuli, including capsaicin-induced inflammatory pain, acetic acid-induced visceral pain, and incision-induced surgical pain, significantly delayed recovery from sevoflurane anesthesia in male mice, whereas this effect was absent in the spared nerve injury-induced chronic pain. Pretreatment with peripheral analgesics could prevent the delayed recovery induced by acute nociception. Furthermore, we found that acute noxious stimuli, induced by the injection of capsaicin under sevoflurane anesthesia, increased c-Fos expression and activity in the GABAergic neurons of the ventrolateral periaqueductal gray. Specific reactivation of capsaicin-activated vlPAGGABA neurons mimicked the effect of capsaicin and its chemogenetic inhibition prevented the delayed recovery from anesthesia induced by capsaicin. Finally, we revealed that the vlPAGGABA neurons regulated the recovery from anesthesia through the inhibition of ventral tegmental area dopaminergic neuronal activity, thus decreasing dopamine (DA) release and activation of DA D1-like receptors in the brain. These findings reveal a novel, cell- and circuit-based mechanism for regulating anesthesia recovery by nociception, and it is important to provide new insights for guiding the management of the anesthesia recovery period.


Assuntos
Anestésicos Inalatórios , Camundongos Endogâmicos C57BL , Nociceptividade , Substância Cinzenta Periaquedutal , Sevoflurano , Sevoflurano/farmacologia , Animais , Masculino , Camundongos , Anestésicos Inalatórios/farmacologia , Nociceptividade/efeitos dos fármacos , Nociceptividade/fisiologia , Substância Cinzenta Periaquedutal/efeitos dos fármacos , Substância Cinzenta Periaquedutal/metabolismo , Mesencéfalo/efeitos dos fármacos , Estado de Consciência/efeitos dos fármacos , Estado de Consciência/fisiologia , Período de Recuperação da Anestesia , Capsaicina/farmacologia , Neurônios GABAérgicos/efeitos dos fármacos , Neurônios GABAérgicos/fisiologia
8.
Cancer Metastasis Rev ; 43(3): 919-939, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38430391

RESUMO

Nasopharyngeal carcinoma (NPC) is characterised by its remarkable geographical and ethnic distribution. The interplay between genetic susceptibility, environmental exposures, and Epstein-Barr virus (EBV) infections is indicated in the development of NPC. Exposure to tobacco smoking, dietary factors, and inhalants has been associated with the risk of NPC. Genetic association studies have revealed NPC-associated susceptibility loci, including genes involved in immune responses, xenobiotic metabolism, genome maintenance, and cell cycle regulation. EBV exposure timing and strain variation might play a role in its carcinogenicity, although further investigations are required. Other factors including medical history and oral hygiene have been implicated in NPC. Prevention strategies, including primary prevention and secondary prevention through early detection, are vital in reducing mortality and morbidity of NPC. The current review discusses the global and regional distribution of NPC incidences, the risk factors associated with NPC, and the public health implications of these insights. Future investigations should consider international, large-scale prospective studies to elucidate the mechanisms underlying NPC pathogenesis and develop individualized interventions for NPC.


Assuntos
Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/epidemiologia , Carcinoma Nasofaríngeo/etiologia , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/epidemiologia , Neoplasias Nasofaríngeas/etiologia , Neoplasias Nasofaríngeas/genética , Fatores de Risco , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/epidemiologia , Incidência , Herpesvirus Humano 4
9.
Plant Physiol ; 195(3): 1954-1968, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38466155

RESUMO

Due to climate change, drought has become a major threat to rice (Oryza sativa L.) growth and yield worldwide. Understanding the genetic basis of drought tolerance in rice is therefore of great importance. Here, we identified a microRNA, miR1432, which regulates rice drought tolerance by targeting the CALMODULIN-LIKE2 (OsCaML2) gene. Mutation of MIR1432 or suppression of miR1432 expression significantly impaired seed germination and seedling growth under drought-stress conditions. Molecular analysis demonstrated that miR1432 affected rice drought tolerance by directly targeting OsCaML2, which encodes an EF-hand chiral calcium-binding protein. Overexpression of a miR1432-resistant form of OsCaML2 (OEmCaML2) phenocopied the mir1432 mutant and miR1432 suppression plants. Furthermore, the suppression of miR1432 severely affected the expression of genes involved in responses to stimulation, metabolism and signal transduction, especially the mitogen-activated protein kinase (MAPK) pathway and hormone transduction pathway in rice under drought stress. Thus, our findings show that the miR1432-OsCaML2 module plays an important role in the regulation of rice drought tolerance, suggesting its potential utilization in developing molecular breeding strategies that improve crop drought tolerance.


Assuntos
Calmodulina , Secas , Regulação da Expressão Gênica de Plantas , MicroRNAs , Oryza , Proteínas de Plantas , Estresse Fisiológico , Oryza/genética , Oryza/fisiologia , MicroRNAs/genética , MicroRNAs/metabolismo , Calmodulina/genética , Calmodulina/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Mutação/genética , Plantas Geneticamente Modificadas , Plântula/genética , Plântula/fisiologia , Plântula/crescimento & desenvolvimento , Adaptação Fisiológica/genética , Germinação/genética
10.
Plant Physiol ; 194(4): 2491-2510, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38039148

RESUMO

Passion fruit (Passiflora edulis) possesses a complex aroma and is widely grown in tropical and subtropical areas. Here, we conducted the de novo assembly, annotation, and comparison of PPF (P. edulis Sims) and YPF (P. edulis f. flavicarpa) reference genomes using PacBio, Illumina, and Hi-C technologies. Notably, we discovered evidence of recent whole-genome duplication events in P. edulis genomes. Comparative analysis revealed 7.6∼8.1 million single nucleotide polymorphisms, 1 million insertions/deletions, and over 142 Mb presence/absence variations among different P. edulis genomes. During the ripening of yellow passion fruit, metabolites related to flavor, aroma, and color were substantially accumulated or changed. Through joint analysis of genomic variations, differentially expressed genes, and accumulated metabolites, we explored candidate genes associated with flavor, aroma, and color distinctions. Flavonoid biosynthesis pathways, anthocyanin biosynthesis pathways, and related metabolites are pivotal factors affecting the coloration of passion fruit, and terpenoid metabolites accumulated more in PPF. Finally, by heterologous expression in yeast (Saccharomyces cerevisiae), we functionally characterized 12 terpene synthases. Our findings revealed that certain TPS homologs in both YPF and PPF varieties produce identical terpene products, while others yield distinct compounds or even lose their functionality. These discoveries revealed the genetic and metabolic basis of unique characteristics in aroma and flavor between the 2 passion fruit varieties. This study provides resources for better understanding the genome architecture and accelerating genetic improvement of passion fruits.


Assuntos
Frutas , Passiflora , Frutas/genética , Odorantes , Passiflora/genética , Passiflora/metabolismo , Multiômica , Terpenos/metabolismo
11.
Mol Psychiatry ; 29(7): 2170-2184, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38454083

RESUMO

Both peripheral and central corticotropin-releasing factor (CRF) systems have been implicated in regulating pain sensation. However, compared with the peripheral, the mechanisms underlying central CRF system in pain modulation have not yet been elucidated, especially at the neural circuit level. The corticoaccumbal circuit, a structure rich in CRF receptors and CRF-positive neurons, plays an important role in behavioral responses to stressors including nociceptive stimuli. The present study was designed to investigate whether and how CRF signaling in this circuit regulated pain sensation under physiological and pathological pain conditions. Our studies employed the viral tracing and circuit-, and cell-specific electrophysiological methods to label the CRF-containing circuit from the medial prefrontal cortex to the nucleus accumbens shell (mPFCCRF-NAcS) and record its neuronal propriety. Combining optogenetic and chemogenetic manipulation, neuropharmacological methods, and behavioral tests, we were able to precisely manipulate this circuit and depict its role in regulation of pain sensation. The current study found that the CRF signaling in the NAc shell (NAcS), but not NAc core, was necessary and sufficient for the regulation of pain sensation under physiological and pathological pain conditions. This process was involved in the CRF-mediated enhancement of excitatory synaptic transmission in the NAcS. Furthermore, we demonstrated that the mPFCCRF neurons monosynaptically connected with the NAcS neurons. Chronic pain increased the protein level of CRF in NAcS, and then maintained the persistent NAcS neuronal hyperactivity through enhancement of this monosynaptic excitatory connection, and thus sustained chronic pain behavior. These findings reveal a novel cell- and circuit-based mechanistic link between chronic pain and the mPFCCRF → NAcS circuit and provide a potential new therapeutic target for chronic pain.


Assuntos
Hormônio Liberador da Corticotropina , Neurônios , Núcleo Accumbens , Córtex Pré-Frontal , Transmissão Sináptica , Hormônio Liberador da Corticotropina/metabolismo , Animais , Núcleo Accumbens/metabolismo , Transmissão Sináptica/fisiologia , Masculino , Neurônios/metabolismo , Neurônios/fisiologia , Córtex Pré-Frontal/metabolismo , Dor/metabolismo , Dor/fisiopatologia , Camundongos , Optogenética/métodos , Vias Neurais/metabolismo , Vias Neurais/fisiologia , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Camundongos Endogâmicos C57BL
12.
Nucleic Acids Res ; 51(D1): D1446-D1456, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36215030

RESUMO

Cotton is an important economic crop, and many loci for important traits have been identified, but it remains challenging and time-consuming to identify candidate or causal genes/variants and clarify their roles in phenotype formation and regulation. Here, we first collected and integrated the multi-omics datasets including 25 genomes, transcriptomes in 76 tissue samples, epigenome data of five species and metabolome data of 768 metabolites from four tissues, and genetic variation, trait and transcriptome datasets from 4180 cotton accessions. Then, a cotton multi-omics database (CottonMD, http://yanglab.hzau.edu.cn/CottonMD/) was constructed. In CottonMD, multiple statistical methods were applied to identify the associations between variations and phenotypes, and many easy-to-use analysis tools were provided to help researchers quickly acquire the related omics information and perform multi-omics data analysis. Two case studies demonstrated the power of CottonMD for identifying and analyzing the candidate genes, as well as the great potential of integrating multi-omics data for cotton genetic breeding and functional genomics research.


Assuntos
Bases de Dados Factuais , Gossypium , Multiômica , Genoma , Genômica/métodos , Fenótipo , Gossypium/química , Gossypium/genética
13.
Proc Natl Acad Sci U S A ; 119(38): e2205842119, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36095196

RESUMO

RNA uridylation, catalyzed by terminal uridylyl transferases (TUTases), represents a conserved and widespread posttranscriptional RNA modification in eukaryotes that affects RNA metabolism. In plants, several TUTases, including HEN1 SUPPRESSOR 1 (HESO1) and UTP: RNA URIDYLYLTRANSFERASE (URT1), have been characterized through genetic and biochemical approaches. However, little is known about their physiological significance during plant development. Here, we show that HESO1 and URT1 act cooperatively with the cytoplasmic 3'-5' exoribonucleolytic machinery component SUPERKILLER 2 (SKI2) to regulate photosynthesis through RNA surveillance of the Calvin cycle gene TRANSKETOLASE 1 (TKL1) in Arabidopsis. Simultaneous dysfunction of HESO1, URT1, and SKI2 resulted in leaf etiolation and reduced photosynthetic efficiency. In addition, we detected massive illegitimate short interfering RNAs (siRNAs) from the TKL1 locus in heso1 urt1 ski2, accompanied by reduced TKL1/2 expression and attenuated TKL activities. Consequently, the metabolic analysis revealed that the abundance of many Calvin cycle intermediates is dramatically disturbed in heso1 urt1 ski2. Importantly, all these molecular and physiological defects were largely rescued by the loss-of-function mutation in RNA-DEPENDENT RNA POLYMERASE 6 (RDR6), demonstrating illegitimate siRNA-mediated TKL silencing. Taken together, our results suggest that HESO1- and URT1-mediated RNA uridylation connects to the cytoplasmic RNA degradation pathway for RNA surveillance, which is crucial for TKL expression and photosynthesis in Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fotossíntese , RNA Nucleotidiltransferases , Estabilidade de RNA , RNA Interferente Pequeno , Transcetolase , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Nucleotidiltransferases/metabolismo , Fotossíntese/genética , RNA Helicases/metabolismo , RNA Nucleotidiltransferases/genética , RNA Nucleotidiltransferases/metabolismo , Estabilidade de RNA/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transcetolase/genética , Transcetolase/metabolismo , Uridina/metabolismo
14.
Proc Natl Acad Sci U S A ; 119(31): e2123241119, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35895679

RESUMO

Somatic mutations are accumulated in normal human tissues with aging and exposure to carcinogens. If we can accurately count any passenger mutations in any single DNA molecule, since their quantity is much larger than driver mutations, we can sensitively detect mutation accumulation in polyclonal normal tissues. Duplex sequencing, which tags both DNA strands in one DNA molecule, enables accurate count of such mutations, but requires a very large number of sequencing reads for each single sample of human-genome size. Here, we reduced the genome size to 1/90 using the BamHI restriction enzyme and established a cost-effective pipeline. The enzymatically cleaved and optimal sequencing (EcoSeq) method was able to count somatic mutations in a single DNA molecule with a sensitivity of as low as 3 × 10-8 per base pair (bp), as assessed by measuring artificially prepared mutations. Taking advantages of EcoSeq, we analyzed normal peripheral blood cells of pediatric sarcoma patients who received chemotherapy (n = 10) and those who did not (n = 10). The former had a mutation frequency of 31.2 ± 13.4 × 10-8 per base pair while the latter had 9.0 ± 4.5 × 10-8 per base pair (P < 0.001). The increase in mutation frequency was confirmed by analysis of the same patients before and after chemotherapy, and increased mutation frequencies persisted 46 to 64 mo after chemotherapy, indicating that the mutation accumulation constitutes a risk of secondary leukemia. EcoSeq has the potential to reveal accumulation of somatic mutations and exposure to environmental factors in any DNA samples and will contribute to cancer risk estimation.


Assuntos
Análise Mutacional de DNA , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala , Taxa de Mutação , Imagem Individual de Molécula , Envelhecimento/genética , Pareamento de Bases , Criança , Análise Mutacional de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Mutação , Imagem Individual de Molécula/métodos
15.
Nano Lett ; 24(40): 12634-12641, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39316509

RESUMO

Spectral polarization imaging is critical for broad applications ranging from remote sensing to biomedicine. Here, we propose and experimentally demonstrate an imaging spectropolarimeter based on a single multifunctional metasurface. The designed metasurface accurately maps spectral and polarization information onto focal points and vortex beams, enabling simultaneous detection through intensity distributions. More specifically, spectral detection is achieved by determining the azimuthal angle of the strongest focal point, while polarization detection is accomplished by synthesizing the intensity of focal points and the interference pattern of output vortex beams. Experimental results indicate the successful reconstruction for six discrete wavelengths, with the average relative polarization error ranging from 7.85% to 13%. Additionally, the metasurface exhibits excellent imaging and edge detection capabilities owing to the focusing properties and the generation of vortex beams, achieving an imaging resolution of up to 1.4-fold wavelength and offering a new solution for a wide range of applications.

16.
Nano Lett ; 24(42): 13388-13396, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39383340

RESUMO

Polarization-sensitive optoelectronic detection has been achieved by an all-Si detector in the NIR range, based on plasmon hot electron generation/internal photoemission effect. An advanced architecture with a specially designed anisotropic metasurface was developed and structurally optimized for maximizing the internal quantum efficiency (IQE). Assisted by finite difference time domain (FDTD) simulations, the well-designed device exhibits a maximum optical absorption of 80% around 1.45 µm, corresponding to an optical discrimination ratio of 120. Optoelectronic measurements show the peak responsivity and detectivity of 51.2 mA/W and 8.05 × 1010 cm Hz1/2/W, respectively, at 1.45 µm. A high polarization photocurrent ratio of 35 nm is also achieved at 1.55 µm. Moreover, the optoelectronic response can be tuned by a back-gate bias. Last but not least, we built up a model for theoretically estimating the IQE, which provides instructive guidance for further enhancing the optoelectronic performance of hot electron detectors.

17.
Nano Lett ; 24(3): 983-992, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38206182

RESUMO

On-chip polarization detectors have attracted extensive research interest due to their filterless and ultracompact architecture. However, their polarization-dependent photoresponses cannot be dynamically adjusted, hindering the development toward intelligence. Here, we propose dynamically reconfigurable polarimetry based on in-sensor differentiation of two self-powered photoresponses with orthogonal polarization dependences and tunable responsivities. Such a device can be electrostatically configured in an ultrahigh polarization extinction ratio (PER) mode, where the PER tends to infinity, a Stokes parameter direct sensing mode, where the photoresponse is proportional to S1 or S2 with high accuracy (RMSES1 = 1.5%, RMSES2 = 2.0%), or a background suppressing mode, where the target-background polarization contrast is singularly enhanced. Moreover, the device achieves a polarization angle sensitivity of 0.51 mA·W-1·degree-1 and a specific polarization angle detectivity of 2.8 × 105 cm·Hz1/2·W·degree-1. This scheme is demonstrated throughout the near-to-long-wavelength infrared range, and it will bring a leap for next-generation on-chip polarimeters.

18.
Gut ; 73(2): 255-267, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37751933

RESUMO

OBJECTIVE: The presence of intestinal metaplasia (IM) is a risk factor for gastric cancer. However, it is still controversial whether IM itself is precancerous or paracancerous. Here, we aimed to explore the precancerous nature of IM by analysing epigenetic alterations. DESIGN: Genome-wide DNA methylation analysis was conducted by EPIC BeadArray using IM crypts isolated by Alcian blue staining. Chromatin immunoprecipitation sequencing for H3K27ac and single-cell assay for transposase-accessible chromatin by sequencing were conducted using IM mucosa. NOS2 was induced using Tet-on gene expression system in normal cells. RESULTS: IM crypts had a methylation profile unique from non-IM crypts, showing extensive DNA hypermethylation in promoter CpG islands, including those of tumour-suppressor genes. Also, the IM-specific methylation profile, namely epigenetic footprint, was present in a fraction of gastric cancers with a higher frequency than expected, and suggested to be associated with good overall survival. IM organoids had remarkably high NOS2 expression, and NOS2 induction in normal cells led to accelerated induction of aberrant DNA methylation, namely epigenetic instability, by increasing DNA methyltransferase activity. IM mucosa showed dynamic enhancer reprogramming, including the regions involved in higher NOS2 expression. NOS2 had open chromatin in IM cells but not in gastric cells, and IM cells had frequent closed chromatin of tumour-suppressor genes, indicating their methylation-silencing. NOS2 expression in IM-derived organoids was upregulated by interleukin-17A, a cytokine secreted by extracellular bacterial infection. CONCLUSIONS: IM cells were considered to have a precancerous nature potentially with an increased chance of converting into cancer cells, and an accelerated DNA methylation induction due to abnormal NOS2 expression.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Lesões Pré-Cancerosas , Neoplasias Gástricas , Humanos , Metilação de DNA , Neoplasias Gástricas/microbiologia , DNA , Cromatina/metabolismo , Metaplasia/genética , Metaplasia/metabolismo , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Mucosa Gástrica/metabolismo , Helicobacter pylori/genética , Infecções por Helicobacter/complicações
19.
BMC Genomics ; 25(1): 188, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38368335

RESUMO

BACKGROUND: Haemonchus contortus (H. contortus) is the most common parasitic nematode in ruminants and is prevalent worldwide. H. contortus resistance to albendazole (ABZ) hinders the efficacy of anthelmintic drugs, but little is known about the molecular mechanisms that regulate this of drug resistance. Recent research has demonstrated that long noncoding RNAs (lncRNAs) can exert significant influence as pivotal regulators of the emergence of drug resistance. RESULTS: In this study, transcriptome sequencing was conducted on both albendazole-sensitive (ABZ-sensitive) and albendazole-resistant (ABZ-resistant) H. contortus strains, with three biological replicates for each group. The analysis of lncRNA in the transcriptomic data revealed that there were 276 differentially expressed lncRNA (DElncRNA) between strains with ABZ-sensitive and ABZ-resistant according to the criteria of |log2Foldchange|≥ 1 and FDR < 0.05. Notably, MSTRG.12969.2 and MSTRG.9827.1 exhibited the most significant upregulation and downregulation, respectively, in the resistant strains. The potential roles of the DElncRNAs included catalytic activity, stimulus response, regulation of drug metabolism, and modulation of the immune response. Moreover, we investigated the interactions between DElncRNAs and other RNAs, specifically MSTRG.12741.1, MSTRG.11848.1, MSTRG.5895.1, and MSTRG.14070.1, involved in regulating drug stimulation through cis/trans/antisense/lncRNA‒miRNA-mRNA interaction networks. This regulation leads to a decrease (or increase) in the expression of relevant genes, consequently enhancing the resistance of H. contortus to albendazole. Furthermore, through comprehensive analysis of competitive endogenous RNAs (ceRNAs) involved in drug resistance-related pathways, such as the mTOR signalling pathway and ABC transporter signalling pathway, the relevance of the MSTRG.2499.1-novel-m0062-3p-HCON_00099610 interaction was identified to mainly involve the regulation of catalytic activity, metabolism, ubiquitination and transcriptional regulation of gene promoters. Additionally, quantitative real-time polymerase chain reaction (qRT-PCR) validation indicated that the transcription profiles of six DElncRNAs and six DEmRNAs were consistent with those obtained by RNA-seq. CONCLUSIONS: The results of the present study allowed us to better understand the changes in the lncRNA expression profile of ABZ-resistant H. contortus. In total, these results suggest that the lncRNAs MSTRG.963.1, MSTRG.12741.1, MSTRG.11848.1 and MSTRG.2499.1 play important roles in the development of ABZ resistance and can serve as promising biomarkers for further study.


Assuntos
Anti-Helmínticos , Haemonchus , RNA Longo não Codificante , Animais , Albendazol/farmacologia , Albendazol/análise , Albendazol/metabolismo , Haemonchus/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Transcriptoma , Anti-Helmínticos/farmacologia , Anti-Helmínticos/metabolismo , Anti-Helmínticos/uso terapêutico
20.
Eur J Neurosci ; 59(3): 446-456, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38123158

RESUMO

The anterior cingulate cortex (ACC) and visual cortex are integral components of the neurophysiological mechanisms underlying migraine, yet the impact of altered connectivity patterns between these regions on migraine treatment remains unknown. To elucidate this issue, we investigated the abnormal causal connectivity between the ACC and visual cortex in patients with migraine without aura (MwoA), based on the resting-state functional magnetic resonance imaging data, and its predictive ability for the efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs). The results revealed increased causal connectivity from the bilateral ACC to the lingual gyrus (LG) and decreased connectivity in the opposite direction in nonresponders compared with the responders. Moreover, compared with the healthy controls, nonresponders exhibited heightened causal connectivity from the ACC to the LG, right inferior occipital gyrus (IOG) and left superior occipital gyrus, while connectivity patterns from the LG and right IOG to the ACC were diminished. Based on the observed abnormal connectivity patterns, the support vector machine (SVM) models showed that the area under the receiver operator characteristic curves for the ACC to LG, LG to ACC and bidirectional models were 0.857, 0.898, and 0.939, respectively. These findings indicate that neuroimaging markers of abnormal causal connectivity in the ACC-visual cortex circuit may facilitate clinical decision-making regarding NSAIDs administration for migraine management.


Assuntos
Enxaqueca sem Aura , Córtex Visual , Humanos , Giro do Cíngulo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Enxaqueca sem Aura/patologia , Córtex Visual/diagnóstico por imagem , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/uso terapêutico , Anti-Inflamatórios , Encéfalo
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