Peter J M Rottier

..The important role of the about 38-residues cytoplasmic domain in the assembly of and membrane fusion by this approximately 1300 amino acids long protein is discussed...

..The implications of these findings are discussed...

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..While cell-cell fusion was clearly affected by preventing spike protein cleavage, virus-cell fusion was not, indicating that these events have different requirements...

..Our observations reveal an important role of the UPS in multiple steps of the CoV infection cycle and identify the UPS as a potential drug target to modulate the impact of CoV infection...

..The observations point to intriguing and as yet unrecognized similarities between the RTC dynamics of different plus-strand RNA viruses...

..More generally, our approach may allow the development of vaccines against infections with other pathogenic coronaviruses, including that causing severe acute respiratory syndrome in humans...

..By these and perhaps other mutations, the virus apparently acquires its macrophage tropism and spreads systemically...

..e., regions far apart in the linear sequence, communicate and may even interact physically in the higher-order structure of the spike...

..Overall, our study shows that the SILAC approach is a suitable tool to study host-pathogen interactions and to identify host proteins involved in virus replication...

..Apparently, 3c-inactivated viruses replicate not at all--or only poorly--in the gut, explaining the rare incidence of FIP outbreaks...

..Our results indicate that the balance between HA and NA is important not only for virion release, but also for entry into cells...

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..The protective effectors against MHV infection are, however, still unknown...

..Surprisingly, however, the drug did not reduce replication of the virus in mice. Rather, inhibition of the proteasome caused enhanced infection with lethal outcome, calling for caution when using this type of drug during infection...

..Moreover, cleavage was mapped to the same region where, in coronaviruses carrying furin-activated spikes, the receptor binding subunit of the protein is separated from the membrane-anchored fusion subunit...

..Recruitment of the N protein to the RTCs requires the C-terminal N2b domain, which interacts with other N proteins in an RNA-independent manner...

..g., murine or feline) cell tropism. Additional mutations created in the donor RNA can be co-incorporated into the recombinant virus in order to generate mutant viruses...

..Clearly, the 29-nucleotide deletion disrupts the proper expression of the SARS-CoV ORF8, the implications of which are discussed...

..The occurrence of conserved non-membrane-spanning hydrophobic domains in nsp3 and nsp6 suggests an important function for these domains in coronavirus replication...

..The fluorescent MHV-SGFP will now be a convenient tool to study coronaviral cell entry...

..In addition, our data highlight the importance of the correct association of the minor EAV envelope glycoproteins for their efficient incorporation into viral particles and for virus infectivity...

..Altogether, our observations clearly demonstrate the potential of coronaviruses as (multivalent) expression vectors...

..We establish the second targeted RNA recombination system for coronaviruses and provide a powerful tool for the genetic engineering of the FIPV genome...

..It can be concluded that by using SILAC-based quantitative proteomics we were able to identify novel host cell proteins involved in the complex interplay between Salmonella and epithelial cells...

..As a consequence, differences in HA fine receptor specificities could not be observed with the insect cell-, but were readily detected with the HEK293S GnTI(-) cell-produced HAs...

..Our findings provide insight into the evolutionary history of coronavirus group 1a and into the dynamics of gain and loss of accessory genes...

..In this brief review, we describe the current understanding of how the SARS-CoV is able to use the cellular machinery for its replication...

..The implications of our results, particularly our insights into the persistently infected state, are discussed...

..Our results provide new insights in coronavirus pathogenesis and demonstrate the potential of BLI to study coronavirus-host interactions in vivo...

..The inhibitory potency of the SARS-CoV HR2-peptides provides an attractive basis for the development of a therapeutic drug for SARS...

..In addition, the coexpression of nsp4 with nsp3 affected the subcellular localization of the two proteins...

..Its inclusion in a vaccine is likely to reduce the HA dose required and to broaden the protective immunity...

..Yet, this effect has not been investigated despite the many reports that describe gene expression profiling of virus-infected cells using microarrays...

..Thus, in addition to the classical dynamin-dependent, clathrin-mediated endocytosis pathway, IAV enters host cells by a dynamin-independent route that has all the characteristics of macropinocytosis...

..Our study reveals that the minor envelope proteins of arteriviruses enter into both covalent and noncovalent interactions, the function of which has yet to be established...

..Both biochemical and functional data show that the coronavirus spike protein is a class I viral fusion protein...

..This apparent correlation might be explained by the functioning of lectins, such as the mannose receptor, which are abundantly expressed in the liver but also play a role in the induction of interferon-alpha by dendritic cells...

..It also depended significantly on the particular genomic location at which the gene was inserted. The data indicate that foreign sequences are more stably maintained when replacing nonessential coronaviral genes...

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..We conclude that the glycosylation state of recombinant antigens is a factor of significant importance when developing glycoprotein-based vaccines, such as recombinant HA proteins...

..Interestingly, whereas alanine at position 200 is found in most new pandemic human viruses, the residue at position 227 in these viruses is invariably a glutamic acid...

..Collectively, our results demonstrate that GBF1-mediated ARF1 activation is required for efficient MHV RNA replication and reveal that the early secretory pathway and MHV replication complex formation are closely connected...

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..In view of the low rate of false-positive results (high specificity) the mRNA RT-PCR may be a valuable addition to the diagnostic arsenal for FIP...

..Rather, late in infection many DMVs may harbor dsRNA molecules that are no longer functioning as intermediates in RNA synthesis...

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..This competition is probably most apparent early during infection, when limiting amounts of polymerases are present, and may contribute to the regulation of segment-specific replication and transcription...

..This is the first demonstration of oncolytic activity of a coronavirus in vivo. It suggests that nonhuman coronaviruses may be attractive new therapeutic agents against human tumors...

..This was confirmed by the lack of inhibition of IAV entry by proteasome inhibitors in a virus-like particle fusion assay...

..Therefore, deletion of the coronavirus group-specific genes seems to provide an attractive approach to generate attenuated live coronavirus vaccines...

..This study shows that DNA vaccination failed to protect cats against FIP and that IL-12 may yield adverse effects when used as a cytokine adjuvant...

..In contrast, FIPV occurs sporadically but is lethal. It replicates in monocytes and macrophages and rapidly disseminates throughout the body causing systemic immunopathologic disease (1-4)...

..However, these findings suggest that a subset of dogs may benefit from anti-EGFR adjuvant therapies...

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..Most, but not all, of the oligosaccharides of these virion glycoproteins are biochemically mature. Our results bring the number of EAV envelope proteins to six...

..Overall, our study shows that the SILAC approach is a suitable tool to study host-pathogen interactions and to identify host proteins involved in virus replication...

..EAV-G(L)Delta or similar mutants are therefore attractive marker vaccine candidates, enabling serological discrimination between vaccinated and wild-type virus-infected animals...

..The results imply that endocytosis plays a major role in MHV-A59 infection and the acidic pH of the endosomal compartment triggers a conformational change of the S protein mediating fusion...

..Finally, one interaction domain was detected in the central, most hydrophobic region of VP5, supporting the idea that this virulence determinant may function as a membrane pore-forming protein in infected cells...

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..As we discuss, the available data indicate that the ILO 5( nucleotide sequence per se, not its functioning in translation initiation, is of critical importance for EAV replication...

..Our data indicate that two coronaviruses that utilize a common receptor nonetheless enter cells through distinct mechanisms...

..VP3 seems to be the key organizer of birnavirus structure, as it maintains critical interactions with all components of the viral particle: itself, VP2, VP1, and the two genomic dsRNAs...