RESUMO
Virus-induced drought tolerance presents a fascinating facet of biotic-abiotic interaction in plants, yet its molecular intricacies remain unclear. Our study shows that cowpea mild mottle virus (CPMMV) infection enhances drought tolerance in common bean (Phaseolus vulgaris) plants through a virus-derived small interfering RNA (vsiRNA)-activated autophagy pathway. Specifically, a 21-bp vsiRNA originating from the CPMMV Triple Gene Block1 (TGB1) gene targeted the 5' untranslated region (UTR) of the host Teosinte branched 1, Cycloidea, Proliferating Cell Factor (TCP) transcription factor gene PvTCP2, independent of the known role of TGB1 as an RNA silencing suppressor. This targeting attenuated the expression of PvTCP2, which encodes a transcriptional repressor, and in turn upregulated the core autophagy-related gene (ATG) PvATG8c, leading to activated autophagy activity surpassing the level induced by drought or CPMMV infection alone. The downstream EARLY RESPONSIVE TO DEHYDRATION (ERD) effector PvERD15 is a homologue of Arabidopsis thaliana AtERD15, which positively regulates stomatal aperture. PvERD15 was degraded in PvATG8c-mediated autophagy. Therefore, we establish a TGB1-PvTCP2-PvATG8c-PvERD15 module as a trans-kingdom fine-tuning mechanism that contributes to virus-induced drought tolerance in plant-drought-virus interactions.
RESUMO
Human bocavirus 1 (HBoV1) is a human parvovirus that causes lower respiratory tract infections in young children. It contains a single-stranded (ss) DNA genome of ~5.5 kb that encodes a small noncoding RNA of 140 nucleotides known as bocavirus-encoded small RNA (BocaSR), in addition to viral proteins. Here, we determined the secondary structure of BocaSR in vivo by using DMS-MaPseq. Our findings reveal that BocaSR undergoes N6-methyladenosine (m6A) modification at multiple sites, which is critical for viral DNA replication in both dividing HEK293 cells and nondividing cells of the human airway epithelium. Mechanistically, we found that m6A-modified BocaSR serves as a mediator for recruiting Y-family DNA repair DNA polymerase (Pol) η and Pol κ likely through a direct interaction between BocaSR and the viral DNA replication origin at the right terminus of the viral genome. Thus, this report represents direct involvement of a viral small noncoding RNA in viral DNA replication through m6A modification.
Assuntos
Adenosina , Replicação do DNA , DNA Viral , DNA Polimerase Dirigida por DNA , RNA Viral , Replicação Viral , Humanos , Adenosina/análogos & derivados , Adenosina/metabolismo , Replicação Viral/genética , DNA Polimerase Dirigida por DNA/metabolismo , DNA Polimerase Dirigida por DNA/genética , DNA Viral/genética , DNA Viral/metabolismo , Células HEK293 , RNA Viral/genética , RNA Viral/metabolismo , Bocavirus Humano/genética , Bocavirus Humano/metabolismo , Genoma Viral/genética , Infecções por Parvoviridae/virologiaRESUMO
Adeno-associated viruses (AAVs) package a single-stranded (ss) DNA genome of 4.7 kb in their capsid of ~20 nm in diameter. AAV replication requires co-infection of a helper virus, such as adenovirus. During the optimization of recombinant AAV production, a small viral nonstructural protein, membrane-associated accessory protein (MAAP), was identified. However, the function of the MAAP in the context of AAV infection remains unknown. Here, we investigated the expression strategy and function of the MAAP during infection of both AAV2 and AAV5 in human embryonic kidney (HEK)293 cells. We found that AAV2 MAAP2 and AAV5 MAAP5 are expressed from the capsid gene (cap)-transcribing mRNA spliced from the donor to the second splice site that encodes VP2 and VP3. Thus, this AAV cap gene transcribes a multicistronic mRNA that can be translated to four viral proteins, MAAP, VP2, AAP, and VP3 in order. In AAV2 infection, MAAP2 predominantly localized in the cytoplasm, alongside the capsid, near the nuclear and plasma membranes, but a fraction of MAAP2 exhibited nuclear localization. In AAV5 infection, MAAP5 revealed a distinct pattern, predominantly localizing within the nucleus. In the cells infected with an MAAP knockout mutant of AAV2 or AAV5, both viral DNA replication and virus replication increased, whereas virus egress decreased, and the decrease in virus egress can be restored by providing MAAP in trans. In summary, MAAP, a novel AAV nonstructural protein translated from a multicistronic viral cap mRNA, not only facilitates cellular egress of AAV but also likely negatively affects viral DNA replication during infection. IMPORTANCE: Recombinant adeno-associated virus (rAAV) has been used as a gene delivery vector in clinical gene therapy. In current gene therapies employing rAAV, a high dose of the vector is required. Consequently, there is a high demand for efficient and high-purity vector production systems. In this study, we demonstrated that membrane-associated accessory protein (MAAP), a small viral nonstructural protein, is translated from the same viral mRNA transcript encoding VP2 and VP3. In AAV-infected cells, apart from its prevalent expression in the cytoplasm with localization near the plasma and nuclear membranes, the MAAP also exhibits notable localization within the nucleus. During AAV infection, MAAP expression increases the cellular egress of progeny virions and decreases viral DNA replication and progeny virion production. Thus, the choice of MAAP expression has pros and cons during AAV infection, which could provide a guide to rAAV production.
Assuntos
Dependovirus , Infecções por Parvoviridae , Proteínas não Estruturais Virais , Humanos , Proteínas do Capsídeo/genética , Dependovirus/genética , Dependovirus/metabolismo , Dependovirus/fisiologia , Células HEK293 , Infecções por Parvoviridae/virologia , Proteínas não Estruturais Virais/metabolismo , Proteínas não Estruturais Virais/genética , Replicação Viral , Genes Virais/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Viral/genética , RNA Viral/metabolismoRESUMO
The gut microbial communities are highly plastic throughout life, and the human gut microbial communities show spatial-temporal dynamic patterns at different life stages. However, the underlying association between gut microbial communities and time-related factors remains unclear. The lack of context-awareness, insufficient data, and the existence of batch effect are the three major issues, making the life trajection of the host based on gut microbial communities problematic. Here, we used a novel computational approach (microDELTA, microbial-based deep life trajectory) to track longitudinal human gut microbial communities' alterations, which employs transfer learning for context-aware mining of gut microbial community dynamics at different life stages. Using an infant cohort, we demonstrated that microDELTA outperformed Neural Network for accurately predicting the age of infant with different delivery mode, especially for newborn infants of vaginal delivery with the area under the receiver operating characteristic curve of microDELTA and Neural Network at 0.811 and 0.436, respectively. In this context, we have discovered the influence of delivery mode on infant gut microbial communities. Along the human lifespan, we also applied microDELTA to a Chinese traveler cohort, a Hadza hunter-gatherer cohort and an elderly cohort. Results revealed the association between long-term dietary shifts during travel and adult gut microbial communities, the seasonal cycling of gut microbial communities for the Hadza hunter-gatherers, and the distinctive microbial pattern of elderly gut microbial communities. In summary, microDELTA can largely solve the issues in tracing the life trajectory of the human microbial communities and generate accurate and flexible models for a broad spectrum of microbial-based longitudinal researches.
Assuntos
Aprendizado Profundo , Microbioma Gastrointestinal , Microbiota , Recém-Nascido , Lactente , Feminino , Humanos , Idoso , DietaRESUMO
Microbiome-based diagnosis of cancer is an increasingly important supplement for the genomics approach in cancer diagnosis, yet current models for microbiome-based diagnosis of cancer face difficulties in generality: not only diagnosis models could not be adapted from one cancer to another, but models built based on microbes from tissues could not be adapted for diagnosis based on microbes from blood. Therefore, a microbiome-based model suitable for a broad spectrum of cancer types is urgently needed. Here we have introduced DeepMicroCancer, a diagnosis model using artificial intelligence techniques for a broad spectrum of cancer types. Built based on the random forest models it has enabled superior performances on more than twenty types of cancers' tissue samples. And by using the transfer learning techniques, improved accuracies could be obtained, especially for cancer types with only a few samples, which could satisfy the requirement in clinical scenarios. Moreover, transfer learning techniques have enabled high diagnosis accuracy that could also be achieved for blood samples. These results indicated that certain sets of microbes could, if excavated using advanced artificial techniques, reveal the intricate differences among cancers and healthy individuals. Collectively, DeepMicroCancer has provided a new venue for accurate diagnosis of cancer based on tissue and blood materials, which could potentially be used in clinics.
Assuntos
Líquidos Corporais , Microbiota , Neoplasias , Humanos , Inteligência Artificial , Neoplasias/diagnóstico , GenômicaRESUMO
BACKGROUND: Hypopharyngeal and laryngeal squamous cell carcinoma (SCC) account for 25-30% of head and neck SCC. Total laryngectomy, while effective, compromises the quality of life. Immune checkpoint inhibitors such as Camrelizumab offer potential in laryngeal preservation. The study investigated Camrelizumab combined with TP regimen as a neoadjuvant therapy for laryngeal preservation in advanced hypopharyngeal and laryngeal SCC. METHODS: A retrospective study was conducted at Sun Yat-sen University Cancer Center on patients diagnosed with locally advanced SCC of the hypopharynx and larynx from October 1, 2019, to October 25, 2022. The efficacy of a first-line treatment combining Camrelizumab (200 mg) and TP regimen (Albumin-bound paclitaxel at 260 mg/m2 and Cisplatin at 60 mg/m2) was evaluated using RECIST 1.1 criteria. Outcomes included overall survival (OS), progression-free survival (PFS), laryngectomy-free survival (LFS), and response rates. RESULTS: Of the 71 included patients, the median age was 60.7 years. Post the first-line treatment, 90.1% demonstrated an overall response. The one-year and two-year OS rates were 91.5% and 84.3%, respectively. One-year and two-year PFS rates were 92.9% and 83.9%, respectively, with LFS at 85.6% and 73.2%. The initial T4 stage as significantly associated with reduced OS and LFS. Skin reaction was the predominant adverse event. CONCLUSION: The Camrelizumab-TP regimen demonstrated promising results for advanced hypopharyngeal/laryngeal SCC patients, exhibiting high response rates, OS, and LFS, positioning it as a potential primary option for laryngeal preservation. Further comprehensive, randomized controlled studies are imperative to validate these initial observations and elucidate the regimen's full clinical efficacy in optimizing laryngeal outcomes.
Assuntos
Anticorpos Monoclonais Humanizados , Neoplasias de Cabeça e Pescoço , Laringe , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estudos Retrospectivos , Hipofaringe , Qualidade de Vida , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológicoRESUMO
IMPORTANCE: The essential steps of successful gene delivery by recombinant adeno-associated viruses (rAAVs) include vector internalization, intracellular trafficking, nuclear import, uncoating, double-stranded (ds)DNA conversion, and transgene expression. rAAV2.5T has a chimeric capsid of AAV2 VP1u and AAV5 VP2 and VP3 with the mutation A581T. Our investigation revealed that KIAA0319L, the multiple AAV serotype receptor, is not essential for vector internalization but remains critical for efficient vector transduction to human airway epithelia. Additionally, we identified that a novel gene WDR63, whose cellular function is not well understood, plays an important role in vector transduction of human airway epithelia but not vector internalization and nuclear entry. Our study also discovered the substantial transduction potential of rAAV2.5T in basal stem cells of human airway epithelia, underscoring its utility in gene editing of human airways. Thus, the knowledge derived from this study holds promise for the advancement of gene therapy in the treatment of pulmonary genetic diseases.
Assuntos
Brônquios , Dependovirus , Epitélio , Técnicas de Transferência de Genes , Vetores Genéticos , Transdução Genética , Humanos , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Dependovirus/genética , Dependovirus/metabolismo , DNA , Epitélio/metabolismo , Epitélio/virologia , Técnicas de Transferência de Genes/tendências , Terapia Genética/métodos , Vetores Genéticos/genética , Brônquios/metabolismo , Brônquios/virologia , Transporte Ativo do Núcleo Celular , Edição de Genes/tendênciasRESUMO
With the rapid accumulation of microbiome data around the world, numerous computational bioinformatics methods have been developed for pattern mining from such paramount microbiome data. Current microbiome data mining methods, such as gene and species mining, rely heavily on sequence comparison. Most of these methods, however, have a clear trade-off, particularly, when it comes to big-data analytical efficiency and accuracy. Microbiome entities are usually organized in ontology structures, and pattern mining methods that have considered ontology structures could offer advantages in mining efficiency and accuracy. Here, we have summarized the ontology-aware neural network (ONN) as a novel framework for microbiome data mining. We have discussed the applications of ONN in multiple contexts, including gene mining, species mining and microbial community dynamic pattern mining. We have then highlighted one of the most important characteristics of ONN, namely, novel knowledge discovery, which makes ONN a standout among all microbiome data mining methods. Finally, we have provided several applications to showcase the advantage of ONN over other methods in microbiome data mining. In summary, ONN represents a paradigm shift for pattern mining from microbiome data: from traditional machine learning approach to ontology-aware and model-based approach, which has found its broad application scenarios in microbiome data mining.
Assuntos
Mineração de Dados , Microbiota , Biologia Computacional , Mineração de Dados/métodos , Aprendizado de Máquina , Redes Neurais de ComputaçãoRESUMO
Microbial community classification enables identification of putative type and source of the microbial community, thus facilitating a better understanding of how the taxonomic and functional structure were developed and maintained. However, previous classification models required a trade-off between speed and accuracy, and faced difficulties to be customized for a variety of contexts, especially less studied contexts. Here, we introduced EXPERT based on transfer learning that enabled the classification model to be adaptable in multiple contexts, with both high efficiency and accuracy. More importantly, we demonstrated that transfer learning can facilitate microbial community classification in diverse contexts, such as classification of microbial communities for multiple diseases with limited number of samples, as well as prediction of the changes in gut microbiome across successive stages of colorectal cancer. Broadly, EXPERT enables accurate and context-aware customized microbial community classification, and potentiates novel microbial knowledge discovery.
Assuntos
Microbioma Gastrointestinal , Microbiota , Aprendizagem , Aprendizado de MáquinaRESUMO
Human bocavirus 1 (HBoV1), a member of the genus Bocaparvovirus of the family Parvoviridae, causes acute respiratory tract infections in young children. Well-differentiated pseudostratified human airway epithelium cultured at an air-liquid interface (HAE-ALI) is an ideal in vitro culture model to study HBoV1 infection. Unique to other parvoviruses, bocaparvoviruses express a small nonstructured protein NP1 of ~25 kDa from an open reading frame (ORF) in the center of the viral genome. NP1 plays an important role in viral DNA replication and pre-mRNA processing. In this study, we performed an affinity purification assay to identify HBoV1 NP1-inteacting proteins. We identified that Ku70 and RPA70 directly interact with the NP1 at a high binding affinity, characterized with an equilibrium dissociation constant (KD) of 95 nM and 122 nM, respectively. Furthermore, we mapped the key NP1-interacting domains of Ku70 at aa266-439 and of RPA70 at aa181-422. Following a dominant negative strategy, we revealed that the interactions of Ku70 and RPA70 with NP1 play a significant role in HBoV1 DNA replication not only in an in vitro viral DNA replication assay but also in HBoV1-infected HAE-ALI cultures. Collectively, our study revealed a novel mechanism by which HBoV1 NP1 enhances viral DNA replication through its direct interactions with Ku70 and RPA70.
Assuntos
Bocavirus Humano , Infecções por Parvoviridae , Criança , Pré-Escolar , Replicação do DNA , DNA Viral/genética , DNA Viral/metabolismo , Genoma Viral , Bocavirus Humano/genética , Bocavirus Humano/metabolismo , Humanos , Replicação Viral/genéticaRESUMO
OBJECTIVE: To identify the causal role of sodium-glucose cotransporter 2 (SGLT2) inhibition on three urological cancers. METHODS: Six single nucleotide polymorphisms associated with the expression level of SLC5A2, a proxy for SGLT2 inhibition, from a recent publication were extracted. Three common urological cancers, including bladder cancer, prostate cancer and kidney cancer, were analysed. The main cohort of bladder cancer was derived from UK Biobank (1279 cases and 372,016 controls). The prostate cancer cohort was from the Prostate Cancer Association Group to Investigate Cancer Associated Alterations in the Genome (PRACTICAL) consortium (79,148 cases and 61,106 controls). The kidney cancer phenotype was from the UK Biobank cohort of 463,010 individuals (1114 cases and 461,896 controls). Primary and sensitivity analysis were performed to validate the results. In vitro analysis was also incorporated to validate the Mendelian randomisation results. RESULTS: In primary analysis, SGLT2 inhibition was associated with reduced risk of bladder cancer (OR: 0.98, 95% CI: 0.97-0.99) per unit lowering of HbA1c level. A protective association was also observed for prostate cancer with odds ratio = 0.31 (95% CI = 0.21-0.47). However, we did not discover a causal relationship between SGLT2 inhibition and kidney cancer (OR: 1.00, 95% CI: 0.99-1.00). Sensitivity analysis and in vitro validation did not support the causal role of SGLT2 inhibition in increasing cancer risk. CONCLUSIONS: We did not find any evidence that SGLT2 inhibition could increase the risk of the three cancers. Even in some analysis, SGLT2 inhibition tended to show protective effects on the three urological cancers.
Assuntos
Neoplasias Renais , Neoplasias da Próstata , Neoplasias da Bexiga Urinária , Neoplasias Urológicas , Masculino , Humanos , Transportador 2 de Glucose-Sódio/genética , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/genética , Neoplasias Urológicas/epidemiologia , Neoplasias Urológicas/genética , Neoplasias Urológicas/complicações , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/complicações , Neoplasias Renais/epidemiologia , Neoplasias Renais/genética , Neoplasias Renais/complicaçõesRESUMO
GMrepo (data repository for Gut Microbiota) is a database of curated and consistently annotated human gut metagenomes. Its main purposes are to increase the reusability and accessibility of human gut metagenomic data, and enable cross-project and phenotype comparisons. To achieve these goals, we performed manual curation on the meta-data and organized the datasets in a phenotype-centric manner. GMrepo v2 contains 353 projects and 71,642 runs/samples, which are significantly increased from the previous version. Among these runs/samples, 45,111 and 26,531 were obtained by 16S rRNA amplicon and whole-genome metagenomics sequencing, respectively. We also increased the number of phenotypes from 92 to 133. In addition, we introduced disease-marker identification and cross-project/phenotype comparison. We first identified disease markers between two phenotypes (e.g. health versus diseases) on a per-project basis for selected projects. We then compared the identified markers for each phenotype pair across datasets to facilitate the identification of consistent microbial markers across datasets. Finally, we provided a marker-centric view to allow users to check if a marker has different trends in different diseases. So far, GMrepo includes 592 marker taxa (350 species and 242 genera) for 47 phenotype pairs, identified from 83 selected projects. GMrepo v2 is freely available at: https://gmrepo.humangut.info.
Assuntos
Bases de Dados Genéticas , Neoplasias Intestinais/microbiologia , Metagenoma , Microbiota , Biomarcadores/sangue , Conjuntos de Dados como Assunto , Microbioma Gastrointestinal/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Internet , Neoplasias Intestinais/sangue , Neoplasias Intestinais/genética , Neoplasias Intestinais/patologia , Anotação de Sequência Molecular , Fenótipo , RNA Ribossômico 16S , SoftwareRESUMO
Information derived from metagenome sequences through deep-learning techniques has significantly improved the accuracy of template free protein structure modeling. However, most of the deep learning-based modeling studies are based on blind sequence database searches and suffer from low efficiency in computational resource utilization and model construction, especially when the sequence library becomes prohibitively large. We proposed a MetaSource model built on 4.25 billion microbiome sequences from four major biomes (Gut, Lake, Soil, and Fermentor) to decode the inherent linkage of microbial niches with protein homologous families. Large-scale protein family folding experiments on 8,700 unknown Pfam families showed that a microbiome targeted approach with multiple sequence alignment constructed from individual MetaSource biomes requires more than threefold less computer memory and CPU (central processing unit) time but generates contact-map and three-dimensional structure models with a significantly higher accuracy, compared with that using combined metagenome datasets. These results demonstrate an avenue to bridge the gap between the rapidly increasing metagenome databases and the limited computing resources for efficient genome-wide database mining, which provides a useful bluebook to guide future microbiome sequence database and modeling development for high-accuracy protein structure and function prediction.
Assuntos
Microbiota/genética , Alinhamento de Sequência/métodos , Análise de Sequência de Proteína/métodos , Algoritmos , Biologia Computacional/métodos , Bases de Dados de Proteínas , Aprendizado Profundo , Ecossistema , Evolução Molecular , Humanos , Metagenoma/genética , Redes Neurais de Computação , Conformação Proteica , Dobramento de Proteína , Proteínas/química , Homologia de SequênciaRESUMO
BACKGROUND: The alteration of chromatin accessibility plays an important role in plant responses to abiotic stress. Carbon-based nanomaterials (CBNMs) have attracted increasing interest in agriculture due to their potential impact on crop productivity, showcasing effects on plant biological processes at transcriptional levels; however, their impact on chromatin accessibility remains unknown. RESULTS: This study found that fullerenol can penetrate the seed coat of pea to mitigate the reduction of seed germination caused by osmotic stress. RNA sequencing (RNA-seq) revealed that the application of fullerenol caused the high expression of genes related to oxidoreduction to return to a normal level. Assay for transposase accessible chromatin sequencing (ATAC-seq) confirmed that fullerenol application reduced the overall levels of chromatin accessibility of numerous genes, including those related to environmental signaling, transcriptional regulation, and metabolism. CONCLUSION: This study suggests that fullerenol alleviates osmotic stress on various fronts, encompassing antioxidant, transcriptional, and epigenetic levels. This advances knowledge of the working mechanism of this nanomaterial within plant cells. © 2024 Society of Chemical Industry.
Assuntos
Montagem e Desmontagem da Cromatina , Fulerenos , Germinação , Osmose , Pisum sativum , Sementes , Sementes/química , Sementes/metabolismo , Sementes/crescimento & desenvolvimento , Germinação/efeitos dos fármacos , Fulerenos/farmacologia , Pisum sativum/metabolismo , Pisum sativum/genética , Pisum sativum/química , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Pressão OsmóticaRESUMO
Lectin receptor-like kinase(LecRLK) is a class of phytokinase with lectin conserved domain, which plays an important role in plant resistance to biological and abiotic stresses, as well as plant growth and development. Cannabis sativa is an important multi-purpose plant, widely used in food, textile, medicine, and other fields. Genome-wide screening and expression analysis of the LecRLK family of C. sativa were performed in this paper, so as to provide scientific reference for functional analysis of the LecRLK family of C. sativa. Based on BLAST and HMM methods, 93 LecRLKs were identified in the whole genome of C. sativa, including 69 G types, 23 L types, and one C types. Subsequently, a series of bioinformatics analyses were performed on the LecRLK family members, and the physicochemical properties of the protein of the LecRLK family members were initially revealed. The prediction of cis-acting elements of promoters in family members showed that family members were regulated by hormones and stress response. The expression analysis showed that some family members were highly expressed in the roots, which may participate in the process of stress resistance. Several members were highly expressed in female flowers and may be involved in female flower development. This study provides a theoretical basis for further study of LecRLK gene function. Meanwhile, the expression analysis screens candidate LecRLK members who may participate in the resistance of C. sativa, which provides a theoretical basis for the subsequent selection of C. sativa varieties against resistance.
Assuntos
Cannabis , Biologia Computacional , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Cannabis/genética , Cannabis/crescimento & desenvolvimento , Cannabis/química , Cannabis/enzimologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/química , Filogenia , Família Multigênica , Genoma de Planta/genéticaRESUMO
Human bocavirus 1 (HBoV1), an autonomous human parvovirus, causes acute respiratory tract infections in young children. HBoV1 infects well-differentiated (polarized) human airway epithelium cultured at an air-liquid interface (HAE-ALI). HBoV1 expresses a large nonstructural protein, NS1, that is essential for viral DNA replication. HBoV1 infection of polarized human airway epithelial cells induces a DNA damage response (DDR) that is critical to viral DNA replication involving DNA repair with error-free Y-family DNA polymerases. HBoV1 NS1 or the isoform NS1-70 per se induces a DDR. In this study, using the second-generation proximity-dependent biotin identification (BioID2) approach, we identified that Ku70 is associated with the NS1-BioID2 pulldown complex through a direct interaction with NS1. Biolayer interferometry (BLI) assay determined a high binding affinity of NS1 with Ku70, which has an equilibrium dissociation constant (KD) value of 0.16 µM and processes the strongest interaction at the C-terminal domain. The association of Ku70 with NS1 was also revealed during HBoV1 infection of HAE-ALI. Knockdown of Ku70 and overexpression of the C-terminal domain of Ku70 significantly decreased HBoV1 replication in HAE-ALI. Thus, our study provides, for the first time, a direct interaction of parvovirus large nonstructural protein NS1 with Ku70. IMPORTANCE Parvovirus infection induces a DNA damage response (DDR) that plays a pivotal role in viral DNA replication. The DDR includes activation of ATM (ataxia telangiectasia mutated), ATR (ATM- and RAD3-related), and DNA-PKcs (DNA-dependent protein kinase catalytic subunit). The large nonstructural protein (NS1) often plays a role in the induction of DDR; however, how the DDR is induced during parvovirus infection or simply by the NS1 is not well studied. Activation of DNA-PKcs has been shown as one of the key DDR pathways in DNA replication of HBoV1. We identified that HBoV1 NS1 directly interacts with Ku70, but not Ku80, of the Ku70/Ku80 heterodimer at high affinity. This interaction is also important for HBoV1 replication in HAE-ALI. We propose that the interaction of NS1 with Ku70 recruits the Ku70/Ku80 complex to the viral DNA replication center, which activates DNA-PKcs and facilitates viral DNA replication.
Assuntos
Bocavirus Humano/fisiologia , Autoantígeno Ku/metabolismo , Mucosa Respiratória/virologia , Proteínas não Estruturais Virais/metabolismo , Replicação Viral , Dano ao DNA , Replicação do DNA , DNA Viral/biossíntese , Genoma Viral , Células HEK293 , Bocavirus Humano/metabolismo , Humanos , Autoantígeno Ku/genética , Ligação Proteica , Domínios Proteicos , Mucosa Respiratória/metabolismo , Proteínas não Estruturais Virais/genética , Compartimentos de Replicação Viral/metabolismoRESUMO
Parvovirus B19 (B19V) infection can cause hematological disorders and fetal hydrops during pregnancy. Currently, no antivirals or vaccines are available for the treatment or prevention of B19V infection. To identify novel small-molecule antivirals against B19V replication, we developed a high-throughput screening (HTS) assay, which is based on an in vitro nicking assay using recombinant N-terminal amino acids 1 to 176 of the viral large nonstructural protein (NS1N) and a fluorescently labeled DNA probe (OriQ) that spans the nicking site of the viral DNA replication origin. We collectively screened 17,040 compounds and identified 2,178 (12.78%) hits that possess >10% inhibition of the NS1 nicking activity, among which 84 hits were confirmed to inhibit nicking in a dose-dependent manner. Using ex vivo-expanded primary human erythroid progenitor cells (EPCs) infected by B19V, we validated 24 compounds that demonstrated >50% in vivo inhibition of B19V infection at 10 µM, which can be categorized into 7 structure scaffolds. Based on the therapeutic index (half-maximal cytotoxic concentration [CC50]/half-maximal effective concentration [EC50] ratio) in EPCs, the top 4 compounds were chosen to examine their inhibitions of B19V infection in EPCs at two times of the 90% maximal effective concentration (EC90). A purine derivative (P7) demonstrated an antiviral effect (EC50 = 1.46 µM) without prominent cytotoxicity (CC50 = 71.8 µM) in EPCs and exhibited 92% inhibition of B19V infection in EPCs at 3.32 µM, which can be used as the lead compound in future studies for the treatment of B19V infection-caused hematological disorders. IMPORTANCE B19V encodes a large nonstructural protein, NS1. Its N-terminal domain (NS1N) consisting of amino acids 1 to 176 binds to viral DNA and serves as an endonuclease to nick the viral DNA replication origins, which is a pivotal step in rolling-hairpin-dependent B19V DNA replication. For high-throughput screening (HTS) of anti-B19V antivirals, we miniaturized a fluorescence-based in vitro nicking assay, which employs a fluorophore-labeled probe spanning the terminal resolution site (trs) and the NS1N protein, into a 384-well-plate format. The HTS assay showed high reliability and capability in screening 17,040 compounds. Based on the therapeutic index (half-maximal cytotoxic concentration [CC50]/half-maximal effective concentration [EC50] ratio) in EPCs, a purine derivative demonstrated an antiviral effect of 92% inhibition of B19V infection in EPCs at 3.32 µM (two times the EC90). Our study demonstrated a robust HTS assay for screening antivirals against B19V infection.
Assuntos
Antivirais/farmacologia , Células Precursoras Eritroides/virologia , Ensaios de Triagem em Larga Escala/métodos , Parvovirus B19 Humano/efeitos dos fármacos , Antivirais/química , Sobrevivência Celular/efeitos dos fármacos , Replicação do DNA/efeitos dos fármacos , DNA Viral/metabolismo , Células Precursoras Eritroides/efeitos dos fármacos , Corantes Fluorescentes , Humanos , Parvovirus B19 Humano/fisiologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Origem de Replicação , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacosRESUMO
Microbiome samples are accumulating at an unprecedented speed. As a result, a massive amount of samples have become available for the mining of the intrinsic patterns among them. However, due to the lack of advanced computational tools, fast yet accurate comparisons and searches among thousands to millions of samples are still in urgent need. In this work, we proposed the Meta-Prism method for comparing and searching the microbial community structures amongst tens of thousands of samples. Meta-Prism is at least 10 times faster than contemporary methods serving the same purpose and can provide very accurate search results. The method is based on three computational techniques: dual-indexing approach for sample subgrouping, refined scoring function that could scrutinize the minute differences among samples, and parallel computation on CPU or GPU. The superiority of Meta-Prism on speed and accuracy for multiple sample searches is proven based on searching against ten thousand samples derived from both human and environments. Therefore, Meta-Prism could facilitate similarity search and in-depth understanding among massive number of heterogenous samples in the microbiome universe. The codes of Meta-Prism are available at: https://github.com/HUST-NingKang-Lab/metaPrism.
Assuntos
Metagenômica/métodos , Microbiota , Humanos , Metagenômica/normas , RNA Ribossômico 16S/genética , Sensibilidade e Especificidade , Software/normasRESUMO
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause the ongoing pandemic of coronavirus disease 2019 (COVID19). One key feature associated with COVID-19 is excessive pro-inflammatory cytokine production that leads to severe acute respiratory distress syndrome. Although the cytokine storm induces inflammatory cell death in the host, which type of programmed cell death mechanism that occurs in various organs and cells remains elusive. Using an in vitro culture model of polarized human airway epithelium (HAE), we observed that necroptosis, but not apoptosis or pyroptosis, plays an essential role in the damage of the epithelial barrier of polarized HAE infected with SARS-CoV-2. Pharmacological inhibitors of necroptosis, necrostatin-2 and necrosulfonamide, efficiently prevented cell death and epithelial barrier dysfunction caused by SARS-CoV-2 infection. Moreover, the silencing of genes that are involved in necroptosis, RIPK1, RIPK3, and MLKL, ameliorated airway epithelial damage of the polarized HAE infected with SARS-CoV-2. This study, for the first time, confirms that SARS-CoV-2 infection triggers necroptosis that disrupts the barrier function of human airway epithelia in vitro.
Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Necroptose , Apoptose , EpitélioRESUMO
Domesticated crops with high yield and quality are frequently susceptible to pathogen attack, whereas enhancement of disease resistance generally compromises crop yield. The underlying mechanisms of how plant development and disease resistance are coordinately programed remain elusive. Here, we showed that the basic Helix-Loop-Helix (bHLH) transcription factor Cucumis sativus Irregular Vasculature Patterning (CsIVP) was highly expressed in cucumber vascular tissues. Knockdown of CsIVP caused severe vasculature disorganization and abnormal organ morphogenesis. CsIVP directly binds to vascular-related regulators YABBY5 (CsYAB5), BREVIPEDICELLUS (CsBP), and AUXIN/INDOLEACETIC ACIDS4 (CsAUX4) and promotes their expression. Knockdown of CsYAB5 resulted in similar phenotypes as CsIVP-RNA interference (RNAi) plants, including disturbed vascular configuration and abnormal organ morphology. Meanwhile, CsIVP-RNAi plants were more resistant to downy mildew and accumulated more salicylic acid (SA). CsIVP physically interacts with NIM1-INTERACTING1 (CsNIMIN1), a negative regulator in the SA signaling pathway. Thus, CsIVP is a novel vasculature regulator functioning in CsYAB5-mediated organ morphogenesis and SA-mediated downy mildew resistance in cucumber.