A5013946002- Viral Infections and Outbreaks Research
- Viral Infections and Vectors
- Viral gastroenteritis research and epidemiology
- Hepatitis B Virus Studies
- Disaster Response and Management
- Mosquito-borne diseases and control
- Virus-based gene therapy research
- COVID-19 epidemiological studies
- SARS-CoV-2 and COVID-19 Research
- Bacteriophages and microbial interactions
- interferon and immune responses
- Bacillus and Francisella bacterial research
- Virology and Viral Diseases
- Zoonotic diseases and public health
- Animal Virus Infections Studies
- Respiratory viral infections research
- Plant Virus Research Studies
- Electron and X-Ray Spectroscopy Techniques
- Advanced Electron Microscopy Techniques and Applications
- Nanopore and Nanochannel Transport Studies
- Plant and Fungal Interactions Research
- RNA modifications and cancer
- Erythrocyte Function and Pathophysiology
- bioluminescence and chemiluminescence research
- RNA Interference and Gene Delivery
Friedrich-Loeffler-Institut
2016-2025
National Institute of Allergy and Infectious Diseases
2011-2019
National Institutes of Health
2011-2019
Institut de Biologie Moléculaire et Cellulaire
2018
GTx (United States)
2018
Office of Extramural Research
2016
State Key Laboratory of Virology
2016
University of Saskatchewan
2015
Liberian Institute for Biomedical Research
2015
Centers for Disease Control and Prevention
2015
Virus entry into host cells is the first step of infection and a crucial determinant pathogenicity. Here we show that Ebola virus-like particles (EBOV-VLPs) composed glycoprotein GP1,2 matrix protein VP40 use macropinocytosis clathrin-mediated endocytosis to enter cells. EBOV-VLPs applied induced actin-driven ruffling enhanced FITC-dextran uptake, which indicated as main mechanism. This was further supported by inhibition through inhibitors actin polymerization (latrunculin A),...
Inclusion bodies are a characteristic feature of ebolavirus infections in cells. They contain large numbers preformed nucleocapsids, but their biological significance has been debated, and they have suggested to be aggregates viral proteins without any further function. However, recent data for other viruses that produce similar structures inclusion might involved genome replication transcription. In order study filovirus bodies, we fused mCherry the polymerase L, which is found bodies. The...
Rapid sequencing of RNA/DNA from pathogen samples obtained during disease outbreaks provides critical scientific and public health information. However, challenges exist for exporting to laboratories or establishing conventional sequencers in remote outbreak regions. We successfully used a novel, pocket-sized nanopore sequencer at field diagnostic laboratory Liberia the current Ebola virus outbreak.
ABSTRACT Work with infectious Ebola viruses is restricted to biosafety level 4 (BSL4) laboratories, presenting a significant barrier for studying these viruses. Life cycle modeling systems, including minigenome systems and transcription- replication-competent virus-like particle (trVLP) allow of the virus life under BSL2 conditions; however, all current model only certain aspects cycle, rely on plasmid-based viral protein expression, have been used single cycles. We developed novel system...
The occurrence of Ebola virus (EBOV) in West Africa during 2013-2015 is unprecedented. Early reports suggested that this outbreak EBOV mutating twice as fast previously observed, which indicates the potential for changes transmissibility and virulence could render current molecular diagnostics countermeasures ineffective. We have determined additional full-length sequences from two clusters imported infections into Mali, we show nucleotide substitution rate (9.6 × 10(-4) substitutions per...
Phosphatidylinositol-3-phosphate 5-kinase (PIKfyve) is a lipid kinase involved in endosome maturation that emerged from haploid genetic screen as being required for Ebola virus (EBOV) infection. Here we analyzed the effects of apilimod, PIKfyve inhibitor was reported to be well tolerated humans phase 2 clinical trials, its on entry and infection EBOV Marburg (MARV). We first found apilimod blocks infections by MARV Huh 7, Vero E6 primary human macrophage cells, with notable potency...
Infectious virus-like particle (iVLP) systems have recently been established for several negative-strand RNA viruses, including the highly pathogenic Zaire ebolavirus (ZEBOV), and allow study of viral life cycle under biosafety level 2 conditions. However, current depend on expression helper nucleocapsid proteins in target cells, thus making it impossible to determine whether ribonucleoprotein complexes transferred by iVLPs are able facilitate initial transcription, an indispensable step...
The morphogenesis and budding of virus particles represent an important stage in the life cycle viruses. For Ebola virus, this process is driven by its major matrix protein, VP40. Like proteins many other nonsegmented, negative-strand RNA viruses, VP40 has been demonstrated to oligomerize occur at least two distinct oligomeric states: hexamers octamers, which are composed antiparallel dimers. While it shown that oligomers essential for viral cycle, their function completely unknown. Here we...
Ebola virus is a non-segmented negative-sense RNA causing severe hemorrhagic fever with high fatality rates in humans and nonhuman primates. For transcription of the viral genome four proteins are essential: nucleoprotein NP, polymerase L, cofactor VP35, VP30. VP30 represents an essential virus-specific factor whose activity regulated via its phosphorylation state. In contrast to transcription, not required for replication. Using minigenome assay, we show that inhibits while replication...
Among the Ebola viruses most species cause severe hemorrhagic fever in humans; however, Reston ebolavirus (REBOV) has not been associated with human disease despite numerous documented infections. While molecular basis for this difference remains unclear, vitro evidence suggested a role glycoprotein (GP) as major filovirus pathogenicity factor, but direct such context of virus infection notably lacking. In order to assess GP EBOV virulence, we have developed novel reverse genetics system...
Ebolaviruses, highly lethal zoonotic pathogens, possess longer genomes than most other non-segmented negative-strand RNA viruses due in part to long 5′ and 3′ untranslated regions (UTRs) present the seven viral transcriptional units. To date, specific functions have not been assigned these UTRs. With reporter assays, we demonstrated that Zaire ebolavirus (EBOV) 5′-UTRs lack internal ribosomal entry site function. However, do differentially regulate cap-dependent translation when placed...
Ebola virus causes devastating hemorrhagic fever outbreaks for which no approved therapeutic exists. The viral nucleocapsid, is minimally composed of the proteins NP, VP35, and VP24, represents an attractive target drug development; however, molecular determinants that govern interactions functions these three are still unknown. Through a series mutational analyses, in combination with biochemical bioinformatics approaches, we identified region on VP24 was critical its interaction NP....
ABSTRACT Bats serve as a reservoir for various, often zoonotic viruses, including significant human pathogens such Ebola and influenza viruses. However, unknown reasons, viral infections rarely cause clinical symptoms in bats. A tight control of replication by the host innate immune defense might contribute to this phenomenon. Transcriptomic studies revealed presence interferon-induced antiviral myxovirus resistance (Mx) proteins bats, but detailed functional aspects have not been assessed....
Ebola virus (EBOV) causes highly pathogenic disease in primates. Through screening a library of human interferon-stimulated genes (ISGs), we identified TRIM25 as potent inhibitor EBOV transcription-and-replication-competent virus-like particle (trVLP) propagation. overexpression inhibited the accumulation viral genomic and messenger RNAs independently RNA sensor RIG-I or secondary proinflammatory gene expression. Deletion strongly attenuated sensitivity trVLPs to inhibition by type-I...
Abstract Ebola viruses (EBOVs) assemble into filamentous virions, whose shape and stability are determined by the matrix viral protein 40 (VP40). Virus entry host cells occurs via membrane fusion in late endosomes; however, mechanism of how remarkably long virions undergo uncoating, including virion disassembly nucleocapsid release cytosol, remains unknown. Here, we investigate structural architecture EBOVs entering discover that VP40 disassembles prior to fusion. We reveal is caused...
Matrix protein VP40 of Ebola virus is essential for assembly and budding. Monomeric can oligomerize in vitro into RNA binding octamers, the crystal structure octameric has revealed that residues Phe125 Arg134 are most important coordination a short single-stranded RNA. Here we show full-length wild-type octamers bind upon HEK 293 cell expression. While Phe125-to-Ala mutation resulted reduced binding, Arg134-to-Ala completely abolished thus octamer formation. The absence formation, however,...
The highly pathogenic Marburg virus (MARV) can only be investigated in high containment laboratories, which is time consuming and expensive. To investigate the MARV life cycle under normal laboratory conditions, an infectious virus-like particle (VLP) system was developed. VLP based on T7-polymerase driven synthesis of a MARV-specific minigenome that encodes luciferase transcribed replicated by simultaneously expressed nucleocapsid proteins NP, VP35, L VP30. Transcription resulted activity...