ABSTRACT
Potyviridae, the largest family of plant RNA viruses, includes many important pathogens that significantly reduce the yields of many crops worldwide. In this study, we report that the 6-kilodalton peptide 1 (6K1), one of the least characterized potyviral proteins, is an endoplasmic reticulum-localized protein. AI-assisted structure modeling and biochemical assays suggest that 6K1 forms pentamers with a central hydrophobic tunnel, can increase the cell membrane permeability of Escherichia coli and Nicotiana benthamiana, and can conduct potassium in Saccharomyces cerevisiae. An infectivity assay showed that viral proliferation is inhibited by mutations that affect 6K1 multimerization. Moreover, the 6K1 or its homologous 7K proteins from other viruses of the Potyviridae family also have the ability to increase cell membrane permeability and transmembrane potassium conductance. Taken together, these data reveal that 6K1 and its homologous 7K proteins function as viroporins in viral infected cells.
Subject(s)
Nicotiana , Nicotiana/virology , Nicotiana/metabolism , Potyviridae/genetics , Potyviridae/metabolism , Viral Proteins/metabolism , Viral Proteins/genetics , Cell Membrane Permeability , Endoplasmic Reticulum/metabolism , Endoplasmic Reticulum/virology , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Viroporin Proteins/metabolism , Viroporin Proteins/genetics , Escherichia coli/genetics , Escherichia coli/metabolism , Plant Viruses/genetics , Plant Viruses/physiology , Plant Diseases/virology , Potassium/metabolismABSTRACT
Viruses can hijack autophagosomes as the nonlytic release vehicles in cultured host cells. However, how autophagosome-mediated viral spread occurs in infected host tissues or organs in vivo remains poorly understood. Here, we report that an important rice reovirus, rice gall dwarf virus (RGDV) hijacks autophagosomes to traverse multiple insect membrane barriers in the midgut and salivary gland of leafhopper vector to enhance viral spread. Such virus-containing double-membraned autophagosomes are prevented from degradation, resulting in increased viral propagation. Mechanistically, viral nonstructural protein Pns11 induces autophagy and embeds itself in the autophagosome membranes. The autophagy-related protein 5 (ATG5)-ATG12 conjugation is essential for initial autophagosome membrane biogenesis. RGDV Pns11 specifically interacts with ATG5, both in vitro and in vivo. Silencing of ATG5 or Pns11 expression suppresses ATG8 lipidation, autophagosome formation, and efficient viral propagation. Thus, Pns11 could directly recruit ATG5-ATG12 conjugation to induce the formation of autophagosomes, facilitating viral spread within the insect bodies. Furthermore, Pns11 potentially blocks autophagosome degradation by directly targeting and mediating the reduced expression of N-glycosylated Lamp1 on lysosomal membranes. Taken together, these results highlight how RGDV remodels autophagosomes to benefit viral propagation in its insect vector.
Subject(s)
Orthoreovirus , Oryza , Reoviridae , Animals , Autophagosomes/metabolism , Autophagy , Insect Vectors , Insecta/metabolism , Oryza/metabolism , Reoviridae/metabolism , Viral Nonstructural Proteins/genetics , Viral Nonstructural Proteins/metabolism , Virus ReplicationABSTRACT
Accumulated experimental evidence has shown that viruses recruit the host intracellular machinery to establish infection. It has recently been shown that the potyvirus Turnip mosaic virus (TuMV) transits through the late endosome (LE) for viral genome replication, but it is still largely unknown how the viral replication vesicles labelled by the TuMV membrane protein 6K2 target LE. To further understand the underlying mechanism, we studied the involvement of the vacuolar sorting receptor (VSR) family proteins from Arabidopsis in this process. We now report the identification of VSR4 as a new host factor required for TuMV infection. VSR4 interacted specifically with TuMV 6K2 and was required for targeting of 6K2 to enlarged LE. Following overexpression of VSR4 or its recycling-defective mutant that accumulates in the early endosome (EE), 6K2 did not employ the conventional VSR-mediated EE to LE pathway, but targeted enlarged LE directly from cis-Golgi and viral replication was enhanced. In addition, VSR4 can be N-glycosylated and this is required for its stability and for monitoring 6K2 trafficking to enlarged LE. A non-glycosylated VSR4 mutant enhanced the dissociation of 6K2 from cis-Golgi, leading to the formation of punctate bodies that targeted enlarged LE and to more robust viral replication than with glycosylated VSR4. Finally, TuMV hijacks N-glycosylated VSR4 and protects VSR4 from degradation via the autophagy pathway to assist infection. Taken together, our results have identified a host factor VSR4 required for viral replication vesicles to target endosomes for optimal viral infection and shed new light on the role of N-glycosylation of a host factor in regulating viral infection.
Subject(s)
Endosomes/metabolism , Host-Pathogen Interactions/physiology , Potyvirus/pathogenicity , Vesicular Transport Proteins/metabolism , Viral Replication Compartments/metabolism , Humans , Plant Diseases/microbiology , Virus Replication/physiologyABSTRACT
BACKGROUND: Polycystic ovary syndrome (PCOS) is a disorder characterized by hyperandrogenism, ovulatory dysfunction, and polycystic ovarian morphologic features, and PCOS is associated with infertility. PH domain Leucine-rich repeat Protein Phosphatase 1 (PHLPP1) has been shown to regulate AKT. The aim of present study is to investigate the role of PHLPP1 in PCOS. METHODS: The expression levels of PHLPP1 in dihydrotestosterone (DHT)-treated human ovarian granular KGN cells were determined by qRT-PCR and Western blot. PHLPP1 was silenced or overexpressed using lentivirus. Cell proliferation was detected by CCK-8. Apoptosis and ROS generation were analyzed by flow cytometry. Glycolysis was analyzed by measuring extracellular acidification rate (ECAR). RESULTS: DHT treatment suppressed proliferation, promoted apoptosis, enhanced ROS, and inhibited glycolysis in KGN cells. PHLPP1 silencing alleviated the DHT-induced suppression of proliferation and glycolysis, and promotion of apoptosis and ROS in KGN cells. PHLPP1 regulated cell proliferation and glycolysis in human KGN cells via the AKT signaling pathway. CONCLUSIONS: Our results showed that PHLPP1 mediates the proliferation and aerobic glycolysis activity of human ovarian granular cells through regulating AKT signaling.
Subject(s)
Polycystic Ovary Syndrome , Female , Humans , Proto-Oncogene Proteins c-akt , Reactive Oxygen Species , Glycolysis , Nuclear Proteins , Phosphoprotein Phosphatases/geneticsABSTRACT
Interactions between plants and microbes are ubiquitous. The outcomes of these interactions involve interkingdom communication, with myriad, diverse signals moving between microbes and their potential plant hosts. Years of biochemical, genetic, and molecular biology research have provided an overview of the landscape of the repertoires of effectors and elicitors encoded by microbes that allow them to stimulate and manipulate responses from their potential plant hosts. Similarly, considerable insight into the plant machinery and capacity for responding to microbes has been gained. The advent of new bioinformatics and modeling approaches has greatly contributed to our understanding of how these interactions occur, and it is expected that these tools, coupled with burgeoning genome sequencing data, will eventually allow the prediction of the outcome of these interactions and whether they will result in a relationship that benefits one or both partners. As a complement to these studies, cell biological studies are elucidating how cells in the plant hosts behave in response to microbial signals. Such studies have brought new attention to the indispensable role of the plant endomembrane system in determining the outcome of plant-microbe interactions. This Focus Issue addresses not only how the plant endomembrane acts locally to mediate responses to microbes but, also, the importance of the plant endomembrane beyond the plant cell borders for cross-kingdom effects. [Formula: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CC0 "No Rights Reserved" license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law, 2023.
Subject(s)
Host Microbial Interactions , Plants , Plants/microbiologyABSTRACT
BACKGROUND: Areca palm (Areca catechu) is a woody perennial plant of both economical and medicinal importance grown in tropical and subtropical climates. Yet, the molecular biology study of areca palm is extremely impeded by its unavailability of a transformation method. An efficient protoplast isolation and transformation system could be highly desirable to overcome this barrier. RESULTS: Here, we described a simple and efficient method for protoplast isolation and transformation from the perennial plant areca palm. A high yield of protoplasts (2.5 × 107 protoplasts per gram of fresh leaf tissues) was obtained from the fresh light green leaflet from the newly-emerged leaf digested overnight in the enzyme solution [2% (w/v) cellulase R10, 0.5% (w/v) macerozyme R10, 0.7 M mannitol, 10 mM CaCl2, 20 mM KCl, 20 mM MES and 0.1% (w/v) BSA, pH 5.7] by the direct leaf-peeling method. The isolated areca protoplasts maintain viability of 86.6% and have been successfully transformed with a green fluorescent protein (GFP)-tagged plasmid (pGreen0029-GFP, 6.0 kb) via the polyethylene glycol (PEG)-mediated transformation. Moreover, the mannitol concentration (optimal: 0.7 M) was determined as a key factor affecting areca protoplast isolation. We also demonstrated that the optimal density of areca protoplast for efficient transformation was at 1.0-1.5 × 106 cells/ml. With the optimization of transformation parameters, we have achieved a relatively high transformation efficiency of nearly 50%. CONCLUSION: We have established the first efficient protocol for the high-yield isolation and transformation of areca palm protoplasts. This method shall be applied in various biological studies of areca palm, such as gene function analysis, genome editing, protein trafficking and localization and protein-protein interaction. In addition, the protoplast system offers a great genetic transformation approach for the woody perennial plant-areca palm. Moreover, the established platform may be applied in protoplast isolation and transformation for other important species in the palm family, including oil palm and coconut.
Subject(s)
Areca , Arecaceae , Protoplasts/metabolism , Plant LeavesABSTRACT
OBJECTIVES: To prospectively assess the diagnostic accuracy of MRI and transvaginal ultrasound (TVS) as well as the prognostic value of MRI for intrauterine adhesions (IUAs), using hysteroscopy as the reference standard. DESIGN: Prospective observational study. SETTING: Tertiary medical centre. PATIENT(S): Ninety-two women with amenorrhea, hypomenorrhea, subfertility, or recurrent pregnancy loss who underwent MRI and in whom Asherman's syndrome was suspected upon TVS. INTERVENTION(S): MRI and TVS were conducted approximately 1 week before hysteroscopy. METHODS: Ninety-two patients suspected of having Asherman's syndrome were examined by MRI and TVS within 7 days of an upcoming hysteroscopy. All hysteroscopy procedures were performed during the early proliferative phase of the menstrual cycle. All hysteroscopic diagnoses were performed by an experienced expert. All MRIs were read by 2 experienced, blinded radiologists. RESULTS: MRI was highly accurate (94.57%), sensitive (98.8%), and specific (42.9%) for diagnosing IUAs with a positive predictive value of 95.5% and a negative predictive value of 75%. The diagnostic values of MRI and TVS were significantly different according to McNemar tests. Junctional zone signal and junctional zone alterations correlated with the stage of IUAs. CONCLUSION: MRI is markedly superior to TVS in terms of diagnostic accuracy for IUAs, with total agreement with hysteroscopic findings. However, the main advantage of MRI is that, unlike TVS and hysterosalpingography, it can be used to assess the risk of hysteroscopy and to predict postoperative recovery and future pregnancy based on the uterine junctional zone.
Subject(s)
Gynatresia , Uterine Diseases , Pregnancy , Humans , Female , Gynatresia/diagnostic imaging , Gynatresia/pathology , Gynatresia/surgery , Uterine Diseases/diagnostic imaging , Uterus/pathology , Hysteroscopy/methods , Tissue Adhesions/diagnostic imaging , Tissue Adhesions/surgery , Magnetic Resonance ImagingABSTRACT
Goldfish have been subjected to over 1,000 y of intensive domestication and selective breeding. In this report, we describe a high-quality goldfish genome (2n = 100), anchoring 95.75% of contigs into 50 pseudochromosomes. Comparative genomics enabled us to disentangle the two subgenomes that resulted from an ancient hybridization event. Resequencing 185 representative goldfish variants and 16 wild crucian carp revealed the origin of goldfish and identified genomic regions that have been shaped by selective sweeps linked to its domestication. Our comprehensive collection of goldfish varieties enabled us to associate genetic variations with a number of well-known anatomical features, including features that distinguish traditional goldfish clades. Additionally, we identified a tyrosine-protein kinase receptor as a candidate causal gene for the first well-known case of Mendelian inheritance in goldfish-the transparent mutant. The goldfish genome and diversity data offer unique resources to make goldfish a promising model for functional genomics, as well as domestication.
Subject(s)
Domestication , Evolution, Molecular , Goldfish/genetics , Selective Breeding/genetics , Animals , Contig Mapping , Datasets as Topic , Female , Fish Proteins/genetics , Genetic Variation , Genome/genetics , Genomics , Hybridization, Genetic , Male , Models, Animal , Phylogeny , Protein-Tyrosine Kinases/geneticsABSTRACT
The hoist cage is used to lift miners in a coal mine's auxiliary shaft. Monitoring miners' unsafe behaviors and their status in the hoist cage is crucial to production safety in coal mines. In this study, a visual detection model is proposed to estimate the number and categories of miners, and to identify whether the miners are wearing helmets and whether they have fallen in the hoist cage. A dataset with eight categories of miners' statuses in hoist cages was developed for training and validating the model. Using the dataset, the classical models were trained for comparison, from which the YOLOv5s model was selected to be the basic model. Due to small-sized targets, poor lighting conditions, and coal dust and shelter, the detection accuracy of the Yolov5s model was only 89.2%. To obtain better detection accuracy, k-means++ clustering algorithm, a BiFPN-based feature fusion network, the convolutional block attention module (CBAM), and a CIoU loss function were proposed to improve the YOLOv5s model, and an attentional multi-scale cascaded feature fusion-based YOLOv5s model (AMCFF-YOLOv5s) was subsequently developed. The training results on the self-built dataset indicate that its detection accuracy increased to 97.6%. Moreover, the AMCFF-YOLOv5s model was proven to be robust to noise and light.
ABSTRACT
Rolling bearings are crucial parts of primary mine fans. In order to guarantee the safety of coal mine production, primary mine fans commonly work during regular operation and are immediately shut down for repair in case of failure. This causes the sample imbalance phenomenon in fault diagnosis (FD), i.e., there are many more normal state samples than faulty ones, seriously affecting the precision of FD. Therefore, the current study presents an FD approach for the rolling bearings of primary mine fans under sample imbalance conditions via symmetrized dot pattern (SDP) images, denoising diffusion probabilistic models (DDPMs), the image generation method, and a convolutional neural network (CNN). First, the 1D bearing vibration signal was transformed into an SDP image with significant characteristics, and the DDPM was employed to create a generated image with similar feature distributions to the real fault image of the minority class. Then, the generated images were supplemented into the imbalanced dataset for data augmentation to balance the minority class samples with the majority ones. Finally, a CNN was utilized as a fault diagnosis model to identify and detect the rolling bearings' operating conditions. In order to assess the efficiency of the presented method, experiments were performed using the regular rolling bearing dataset and primary mine fan rolling bearing data under actual operating situations. The experimental results indicate that the presented method can more efficiently fit the real image samples' feature distribution and generate image samples with higher similarity than other commonly used methods. Moreover, the diagnostic precision of the FD model can be effectively enhanced by gradually expanding and enhancing the unbalanced dataset.
ABSTRACT
In this study, we demonstrate a novel pro-viral role for the Nicotiana benthamiana ARGONAUTE 1 (AGO1) in potyvirus infection. AGO1 strongly enhanced potato virus A (PVA) particle production and benefited the infection when supplied in excess. We subsequently identified the potyviral silencing suppressor, helper-component protease (HCPro), as the recruiter of host AGO1. After the identification of a conserved AGO1-binding GW/WG motif in potyviral HCPros, we used site-directed mutagenesis to introduce a tryptophan-to-alanine change into the HCPro (HCProAG) of PVA (PVAAG) and turnip mosaic virus (TuMVAG). AGO1 co-localization and co-immunoprecipitation with PVA HCPro was significantly reduced by the mutation suggesting the interaction was compromised. Although the mutation did not interfere with HCPro's complementation or silencing suppression capacity, it nevertheless impaired virus particle accumulation and the systemic spread of both PVA and TuMV. Furthermore, we found that the HCPro-AGO1 interaction was important for AGO1's association with the PVA coat protein. The coat protein was also more stable in wild type PVA infection than in PVAAG infection. Based on these findings we suggest that potyviral HCPro recruits host AGO1 through its WG motif and engages AGO1 in the production of stable virus particles, which are required for an efficient systemic infection.
Subject(s)
Nicotiana/virology , Plant Diseases/virology , Plant Proteins/metabolism , Potyvirus/physiology , RNA Interference , Viral Proteins/metabolism , Mutation , Plant Proteins/genetics , Nicotiana/genetics , Nicotiana/metabolism , Viral Proteins/geneticsABSTRACT
Rolling bearings are a vital component of mechanical equipment. It is crucial to implement rolling bearing fault diagnosis research to guarantee the stability of the long-term action of mechanical equipment. Conversion of rolling bearing vibration signals into images for fault diagnosis research has been a practical diagnostic approach. The current paper presents a rolling bearing fault diagnosis method using symmetrized dot pattern (SDP) images and a deep residual network with convolutional block attention module (CBAM-DRN). The rolling bearing vibration signal is first visualized and transformed into an SDP image with distinct fault characteristics. Then, CBAM-DRN is utilized to derive characteristics directly and detect faults from the input SDP images. In order to prevent conventional time-frequency images from being limited by their inherent flaws and avoid missing the fault features, the SDP technique is employed to convert vibration signals into images for visualization. DRN enables adequate extraction of rolling bearing fault characteristics and prevents training difficulties and gradient vanishing in deep level networks. CBAM assists the diagnostic model in concentrating on the image's more distinctive parts and preventing the interference of non-featured parts. Finally, the method's validity was tested with a composite fault dataset of motor bearings containing multiple loads and fault diameters. The experimental results reflect that the presented approach can attain a diagnostic precision of over 99% and good stability and generalization.
Subject(s)
Intelligence , Records , VibrationABSTRACT
Endocytosis and endosomal trafficking play essential roles in diverse biological processes including responses to pathogen attack. It is well established that animal viruses enter host cells through receptor-mediated endocytosis for infection. However, the role of endocytosis in plant virus infection still largely remains unknown. Plant dynamin-related proteins 1 (DRP1) and 2 (DRP2) are the large, multidomain GTPases that participate together in endocytosis. Recently, we have discovered that DRP2 is co-opted by Turnip mosaic virus (TuMV) for infection in plants. We report here that DRP1 is also required for TuMV infection. We show that overexpression of DRP1 from Arabidopsis thaliana (AtDRP1A) promotes TuMV infection, and AtDRP1A interacts with several viral proteins including VPg and cylindrical inclusion (CI), which are the essential components of the virus replication complex (VRC). AtDRP1A colocalizes with the VRC in TuMV-infected cells. Transient expression of a dominant negative (DN) mutant of DRP1A disrupts DRP1-dependent endocytosis and supresses TuMV replication. As adaptor protein (AP) complexes mediate cargo selection for endocytosis, we further investigated the requirement of AP in TuMV infection. Our data suggest that the medium unit of the AP2 complex (AP2ß) is responsible for recognizing the viral proteins as cargoes for endocytosis, and knockout of AP2ß impairs intracellular endosomal trafficking of VPg and CI and inhibits TuMV replication. Collectively, our results demonstrate that DRP1 and AP2ß are two proviral host factors of TuMV and shed light into the involvement of endocytosis and endosomal trafficking in plant virus infection.
Subject(s)
Arabidopsis Proteins/metabolism , Dynamins/metabolism , Plant Viruses/metabolism , RNA Viruses/metabolism , Viral Proteins/metabolism , Arabidopsis Proteins/genetics , Dynamins/genetics , Endocytosis , Endosomes , Gene Expression Regulation, Plant , Gene Knockout Techniques , Host-Pathogen Interactions/physiology , Plant Diseases , Plant Viruses/pathogenicity , Plants, Genetically Modified , Potyvirus , Protein Interaction Domains and Motifs , RNA Viruses/pathogenicity , Nicotiana/genetics , Virus Replication/physiologyABSTRACT
P3N-PIPO, the only dedicated movement protein (MP) of potyviruses, directs cylindrical inclusion (CI) protein from the cytoplasm to the plasmodesma (PD), where CI forms conical structures for intercellular movement. To better understand potyviral cell-to-cell movement, we further characterized P3N-PIPO using Turnip mosaic virus (TuMV) as a model virus. We found that P3N-PIPO interacts with P3 via the shared P3N domain and that TuMV mutants lacking the P3N domain of either P3N-PIPO or P3 are defective in cell-to-cell movement. Moreover, we found that the PIPO domain of P3N-PIPO is sufficient to direct CI to the PD, whereas the P3N domain is necessary for localization of P3N-PIPO to 6K2-labeled vesicles or aggregates. Finally, we discovered that the interaction between P3 and P3N-PIPO is essential for the recruitment of CI to cytoplasmic 6K2-containing structures and the association of 6K2-containing structures with PD-located CI inclusions. These data suggest that both P3N and PIPO domains are indispensable for potyviral cell-to-cell movement and that the 6K2 vesicles in proximity to PDs resulting from multipartite interactions among 6K2, P3, P3N-PIPO, and CI may also play an essential role in this process.IMPORTANCE Potyviruses include numerous economically important viruses that represent approximately 30% of known plant viruses. However, there is still limited information about the mechanism of potyviral cell-to-cell movement. Here, we show that P3N-PIPO interacts with and recruits CI to the PD via the PIPO domain and interacts with P3 via the shared P3N domain. We further report that the interaction of P3N-PIPO and P3 is associated with 6K2 vesicles and brings the 6K2 vesicles into proximity with PD-located CI structures. These results support the notion that the replication and cell-to-cell movement of potyviruses are processes coupled by anchoring viral replication complexes at the entrance of PDs, which greatly increase our knowledge of the intercellular movement of potyviruses.
Subject(s)
Cell Movement/physiology , Potyvirus/metabolism , Viral Proteins/chemistry , Viral Proteins/metabolism , Virus Replication/physiology , Plant Diseases/virology , Plasmodesmata , Protein Domains , Protein Interaction Domains and Motifs , Nicotiana/virologyABSTRACT
Potyviridae is the largest family of plant-infecting RNA viruses and includes many agriculturally and economically important viral pathogens. The viruses in the family, known as potyvirids, possess single-stranded, positive-sense RNA genomes with polyprotein processing as a gene expression strategy. The N-terminal regions of potyvirid polyproteins vary greatly in sequence. Previously, we identified a novel virus species within the family, Areca palm necrotic spindle-spot virus (ANSSV), which was predicted to encode two cysteine proteases, HCPro1 and HCPro2, in tandem at the N-terminal region. Here, we present evidence showing self-cleavage activity of these two proteins and define their cis-cleavage sites. We demonstrate that HCPro2 is a viral suppressor of RNA silencing (VSR), and both the variable N-terminal and conserved C-terminal (protease domain) moieties have antisilencing activity. Intriguingly, the N-terminal region of HCPro1 also has RNA silencing suppression activity, which is, however, suppressed by its C-terminal protease domain, leading to the functional divergence of HCPro1 and HCPro2 in RNA silencing suppression. Moreover, the deletion of HCPro1 or HCPro2 in a newly created infectious clone abolishes viral infection, and the deletion mutants cannot be rescued by addition of corresponding counterparts of a potyvirus. Altogether, these data suggest that the two closely related leader proteases of ANSSV have evolved differential and essential functions to concertedly maintain viral viability.IMPORTANCE The Potyviridae represent the largest group of known plant RNA viruses and account for more than half of the viral crop damage worldwide. The leader proteases of viruses within the family vary greatly in size and arrangement and play key roles during the infection. Here, we experimentally demonstrate the presence of a distinct pattern of leader proteases, HCPro1 and HCPro2 in tandem, in a newly identified member within the family. Moreover, HCPro1 and HCPro2, which are closely related and typically characterized with a short size, have evolved contrasting RNA silencing suppression activity and seem to function in a coordinated manner to maintain viral infectivity. Altogether, the new knowledge fills a missing piece in the evolutionary relationship history of potyvirids and improves our understanding of the diversification of potyvirid genomes.
Subject(s)
Cysteine Proteases/metabolism , Potyviridae/enzymology , RNA Interference , Viral Proteins/metabolism , Amino Acid Sequence , Cysteine Proteases/genetics , Genes, Suppressor , Genome, Viral , Microbial Viability , Mutation , Phylogeny , Plant Diseases/virology , Polyproteins , Potyviridae/genetics , Protein Domains , RNA, Viral/genetics , Viral Proteins/geneticsABSTRACT
Exportin 1/XPO1 is an important nuclear export receptor that binds directly to cargo proteins and translocates the cargo proteins to the cytoplasm. To understand XPO1 protein functions during potyvirus infections, we investigated the nuclear export of the NIb protein encoding the RNA-dependent RNA polymerase (RdRp) of turnip mosaic virus (TuMV). Previously, we found that NIb is transported to the nucleus after translation and sumoylated by the sumoylation (small ubiquitin-like modifier) pathway to support viral infection. Here, we report that XPO1 interacts with NIb to facilitate translocation from the nucleus to the viral replication complexes (VRCs) that accumulate in the perinuclear regions of TuMV-infected cells. XPO1 contains two NIb-binding domains that recognize and interact with NIb in the nucleus and in the perinuclear regions, respectively, which facilitates TuMV replication. Moreover, XPO1 is involved in nuclear export of the sumoylated NIb and host factors tagged with SUMO3 that is essential for suppression of plant immunity in the nucleus. Deficiencies of XPO1 in Arabidopsis and Nicotiana benthamiana plants inhibit TuMV replication and infection. These data demonstrate that XPO1 functions as a host factor in TuMV infection by regulating NIb nucleocytoplasmic transport and plant immunity.
Subject(s)
Potyvirus , Viral Replicase Complex Proteins , Karyopherins , Plant Diseases , Plant Immunity , Receptors, Cytoplasmic and Nuclear , Nicotiana , Viral Proteins , Exportin 1 ProteinABSTRACT
BACKGROUND: Cervical cancer ranks as the fourth leading cause of death from cancer in women. Historically, women with metastatic or recurrent cervical cancer have had limited treatment options. New anti-angiogenesis therapies, such as vascular endothelial growth factor (VEGF) targeting agents, offer an alternative strategy to conventional chemotherapy; they act by inhibiting the growth of new blood vessels, thereby restricting tumour growth by blocking the blood supply. OBJECTIVES: To assess the benefits and harms of VEGF targeting agents in the management of persistent, recurrent, or metastatic cervical cancer. SEARCH METHODS: We performed searches of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, online registers of clinical trials, and abstracts of scientific meetings up until 27 May 2020. SELECTION CRITERIA: We examined randomised controlled trials (RCTs) that evaluated the use of VEGF targeting agents alone or in combination with conventional chemotherapy or other VEGF targeting agents. DATA COLLECTION AND ANALYSIS: Three review authors independently screened the results of search strategies, extracted data, assessed risk of bias, and analysed data according to the standard methods expected by Cochrane. The certainty of evidence was assessed via the GRADE approach. MAIN RESULTS: A total of 1634 records were identified. From these, we identified four studies with a total of 808 participants for inclusion. We also identified two studies that were awaiting classification and nine ongoing studies. Bevacizumab plus chemotherapy versus chemotherapy Treatment with bevacizumab plus chemotherapy may result in lower risk of death compared to chemotherapy alone (hazard ratio (HR) 0.77, 95% confidence interval (CI) 0.62 to 0.95; 1 study, 452 participants; low-certainty evidence). However, there are probably more specific adverse events when compared to chemotherapy alone, including gastrointestinal perforations or fistulae (risk ratio (RR) 18.00, 95% CI 2.42 to 133.67; 1 study, 440 participants; moderate-certainty evidence); serious thromboembolic events (RR 4.5, 95% CI 1.55 to 13.08; 1 study, 440 participants; moderate-certainty evidence); and hypertension (RR 13.75, 95% CI 5.07 to 37.29; 1 study, 440 participants; moderate-certainty evidence). There may also be a higher incidence of serious haemorrhage (RR 5.00, 95% CI 1.11 to 22.56; 1 study, 440 participants; low-certainty evidence). In addition, the incidence of serious adverse events is probably higher (RR 1.44, 95% CI 1.16 to 1.79; 1 study, 439 participants; moderate-certainty evidence). The incremental cost-effectiveness ratio was USD 295,164 per quality-adjusted life-year (1 study, 452 participants; low-certainty evidence). Cediranib plus chemotherapy versus chemotherapy Treatment with cediranib plus chemotherapy may or may not result in similar risk of death when compared to chemotherapy alone (HR 0.94, 95% CI 0.53 to 1.65; 1 study, 69 participants; low-certainty evidence). We found very uncertain results for the incidences of specific adverse events, including gastrointestinal perforations or fistulae (RR 3.27, 95% CI 0.14 to 77.57; 1 study, 67 participants; very low-certainty evidence); serious haemorrhage (RR 5.45, 95% CI 0.27 to 109.49; 1 study, 67 participants; very low-certainty evidence); serious thromboembolic events (RR 3.41, 95% CI 0.14 to 80.59; 1 study, 60 participants; very low-certainty evidence); and serious hypertension (RR 0.36, 95% CI 0.02 to 8.62; 1 study, 67 participants; very low-certainty evidence). In addition, there may or may not be a similar incidence of serious adverse events compared to chemotherapy alone (RR 1.15, 95% CI 0.75 to 1.78; 1 study, 67 participants; low-certainty evidence). Apatinib plus chemotherapy or chemotherapy/brachytherapy versus chemotherapy or chemotherapy/brachytherapy Treatment with apatinib plus chemotherapy or chemotherapy/brachytherapy may or may not result in similar risk of death compared to chemotherapy alone or chemotherapy/brachytherapy alone (HR 0.90, 95% CI 0.51 to 1.60; 1 study, 52 participants; low-certainty evidence). However, hypertension events may occur at a higher incidence as compared to chemotherapy alone or chemotherapy/brachytherapy alone (RR 5.14, 95% CI 1.28 to 20.73; 1 study, 52 participants; low-certainty evidence). Pazopanib plus lapatinib versus lapatinib Treatment with pazopanib plus lapatinib may result in higher risk of death compared to lapatinib alone (HR 2.71, 95% CI 1.16 to 6.31; 1 study, 117 participants; low-certainty evidence). We found very uncertain results for the incidences of specific adverse events, including gastrointestinal perforations or fistulae (RR 2.00, 95% CI 0.19 to 21.59; 1 study, 152 participants; very low-certainty evidence); haemorrhage (RR 2.00, 95% CI 0.72 to 5.58; 1 study, 152 participants; very low-certainty evidence); and thromboembolic events (RR 3.00, 95% CI 0.12 to 72.50; 1 study, 152 participants; very low-certainty evidence). In addition, the incidence of hypertension events is probably higher (RR 12.00, 95% CI 2.94 to 49.01; 1 study, 152 participants; moderate-certainty evidence). There may or may not be a similar incidence of serious adverse events as compared to lapatinib alone (RR 1.45, 95% CI 0.94 to 2.26; 1 study, 152 participants; low-certainty evidence). Pazopanib versus lapatinib Treatment with pazopanib may or may not result in similar risk of death as compared to lapatinib (HR 0.96, 95% CI 0.67 to 1.38; 1 study, 152 participants; low-certainty evidence). We found very uncertain results for the incidences of specific adverse events, including gastrointestinal perforations or fistulae (RR 1.03, 95% CI 0.07 to 16.12; 1 study, 150 participants; very low-certainty evidence); haemorrhage (RR 1.03, 95% CI 0.31 to 3.40; 1 study, 150 participants; very low-certainty evidence); and thromboembolic events (RR 3.08, 95% CI 0.13 to 74.42; 1 study, 150 participants; very low-certainty evidence). In addition, the incidence of hypertension events is probably higher (RR 11.81, 95% CI 2.89 to 48.33; 1 study, 150 participants; moderate-certainty evidence). The risk of serious adverse events may or may not be similar as compared to lapatinib (RR 1.31, 95% CI 0.83 to 2.07; 1 study, 150 participants; low-certainty evidence). AUTHORS' CONCLUSIONS: We found low-certainty evidence in favour of the use of bevacizumab plus chemotherapy. However, bevacizumab probably increases specific adverse events (gastrointestinal perforations or fistulae, thromboembolic events, hypertension) and serious adverse events. We found low-certainty evidence that does not support the use of cediranib plus chemotherapy, apatinib plus chemotherapy, apatinib plus chemotherapy/brachytherapy, or pazopanib monotherapy. We found low-certainty evidence suggesting that pazopanib plus lapatinib worsens outcomes. The VEGF inhibitors apatinib and pazopanib may increase the probability of hypertension events.
Subject(s)
Angiogenesis Inhibitors/therapeutic use , Antineoplastic Agents/therapeutic use , Neoplasm Recurrence, Local/drug therapy , Uterine Cervical Neoplasms/drug therapy , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Adult , Aged , Aged, 80 and over , Angiogenesis Inhibitors/adverse effects , Antineoplastic Agents/adverse effects , Bevacizumab/adverse effects , Bevacizumab/therapeutic use , Bias , Brachytherapy/adverse effects , Combined Modality Therapy/adverse effects , Combined Modality Therapy/methods , Confidence Intervals , Female , Gastric Fistula/chemically induced , Gastrointestinal Hemorrhage/chemically induced , Humans , Hypertension/chemically induced , Indazoles , Intestinal Fistula/chemically induced , Intestinal Perforation/chemically induced , Lapatinib/adverse effects , Lapatinib/therapeutic use , Middle Aged , Neoplasm Recurrence, Local/blood supply , Neoplasm Recurrence, Local/mortality , Progression-Free Survival , Pyridines/adverse effects , Pyridines/therapeutic use , Pyrimidines/adverse effects , Pyrimidines/therapeutic use , Quality of Life , Quinazolines/adverse effects , Quinazolines/therapeutic use , Randomized Controlled Trials as Topic , Sulfonamides/adverse effects , Sulfonamides/therapeutic use , Thromboembolism/chemically induced , Uterine Cervical Neoplasms/blood supply , Uterine Cervical Neoplasms/mortality , Young AdultABSTRACT
A successful viral infection requires complex, compatible molecular interactions between the invading virus and the host. A better understanding of such interactions may assist in the development of novel approaches to control viral diseases for sustainable crop production. In the past decade, the cell biology of virus-host and virus-vector interactions has been one of the most exciting areas of research in the molecular plant-microbe field. This is partially attributed to the availability of powerful cell biology techniques, including imaging tools like confocal microscopy and electron microscopy and tomography. As a result, there has been an unprecedented increase in knowledge in the areas of the bi- and tripartite interactions of virus, host, and vector. We now have a much clearer picture of viral virulence mechanisms, virus-induced host defenses, viral counteracting strategies, and viral circulations in the insect vectors. This Focus Issue highlights molecular virus-plant and virus-vector interactions in the areas of cell biology and closely related disciplines and explores biotechnology-based antiviral strategies using knowledge generated from these research areas.
Subject(s)
Host-Pathogen Interactions , Insect Vectors , Plant Diseases , Plant Viruses , Animals , Disease Resistance , Host-Pathogen Interactions/physiology , Insect Vectors/virology , Plant Diseases/virology , Plants/virologyABSTRACT
This article is part of the Top 10 Unanswered Questions in MPMI invited review series.The past few decades have seen major discoveries in the field of molecular plant-microbe interactions. As the result of technological and intellectual advances, we are now able to answer questions at a level of mechanistic detail that we could not have imagined possible 20 years ago. The MPMI Editorial Board felt it was time to take stock and reassess. What big questions remain unanswered? We knew that to identify the fundamental, overarching questions that drive our research, we needed to do this as a community. To reach a diverse audience of people with different backgrounds and perspectives, working in different areas of plant-microbe interactions, we queried the more than 1,400 participants at the 2019 International Congress on Molecular Plant-Microbe Interactions meeting in Glasgow. This group effort resulted in a list of ten, broad-reaching, fundamental questions that influence and inform our research. Here, we introduce these Top 10 unanswered questions, giving context and a brief description of the issues. Each of these questions will be the subject of a detailed review in the coming months. We hope that this process of reflecting on what is known and unknown and identifying the themes that underlie our research will provide a framework to use going forward, giving newcomers a sense of the mystery of the big questions and inspiring new avenues and novel insights.[Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.