The Experts below are selected from a list of 1584 Experts worldwide ranked by ideXlab platform
Horst Schroten - One of the best experts on this subject based on the ideXlab platform.
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pandemic gii 4 sydney and epidemic gii 17 kawasaki308 noroviruses display distinct specificities for histo blood group antigens leading to different transmission vector dynamics in pacific oysters
Frontiers in Microbiology, 2018Co-Authors: Vasily Morozov, Franzgeorg Hanisch, Mathias K Wegner, Horst SchrotenAbstract:Noroviruses are the major cause of foodborne outbreaks of acute gastroenteritis, which are quiet often linked to raw oyster consumption. Previous studies have suggested histo-blood group antigens (HBGA)-like structures in the oyster tissues as ligands for norovirus binding and persistence. To better understand how oysters can function as vectors for common human noroviruses we have first tested the ability of the GI.1 West Chester, the pandemic GII.4 Sydney, and the epidemic GII.17 Kawasaki308 strains to interact with oyster tissues, and secondly explored how the HBGA preferences of these strains can affect their persistence in oyster tissues. We have found limited HBGA expression in oyster tissues. Only A and H type 1 HBGAs were present in digestive tissues and palps of the Pacific oyster Crassostrea gigas, while gills and mantle lack any HBGA structures. Virus-Like particles (VLPs) of the GI.1 West Chester norovirus reacted with the digestive tissues and palps. Despite of the lack of HBGA expression in mantle, dominant GII.4 Sydney strain readily bound to all the oyster tissues, including digestive tissues, gills, palps, and mantle. In contrast, no binding of the epidemic GII.17 Kawasaki308 VLPs to any oyster tissues was observed. In synthetic HBGA and saliva-binding assays, GI.1 reacted with A type, H type, and Lewis b HBGAs. GII.4 Sydney VLPs showed a broad binding pattern and interacted with various HBGA types, including H type 1 structures. Compared to GI.1 and GII.4 VLPs, the GII.17 Kawasaki308 VLPs only weakly associated with HBGAs carbohydrates and mainly exhibited low affinity binding to long-chain saccharides containing A type, B type, H type, Leb blood group epitopes. Our findings therefore indicate that GI.1 and GII.4 noroviruses are likely to be concentrated in the oysters via HBGA-like glycans potentially leading to increased long term transmission, while for the GII.17 Kawasaki308 strain oysters can only function as short term transmission vectors in periods of high environmental virus concentrations.
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Data_Sheet_1_Pandemic GII.4 Sydney and Epidemic GII.17 Kawasaki308 Noroviruses Display Distinct Specificities for Histo-Blood Group Antigens Leading to Different Transmission Vector Dynamics in Pacific Oysters.docx
2018Co-Authors: Vasily Morozov, Franzgeorg Hanisch, Mathias K Wegner, Horst SchrotenAbstract:Noroviruses are the major cause of foodborne outbreaks of acute gastroenteritis, which are often linked to raw oyster consumption. Previous studies have suggested histo-blood group antigens (HBGA)-like structures in the oyster tissues as ligands for norovirus binding and persistence. To better understand how oysters function as vectors for the most common human noroviruses, we first tested the ability of the norovirus strains GI.1 West Chester, the pandemic GII.4 Sydney, and the epidemic GII.17 Kawasaki308 strains to interact with oyster tissues. Secondly, we explored how the HBGA preferences of these strains can affect their persistence in oyster tissues. We found limited HBGA expression in oyster tissues. HBGAs of A and H type 1 were present in the digestive tissues and palps of the Pacific oyster Crassostrea gigas, while the gills and mantle lacked any HBGA structures. By using Virus-like particles (VLPs), which are antigenically and morphologically similar to native virions, we were able to demonstrate that VLPs of GI.1 West Chester norovirus reacted with the digestive tissues and palps. Despite of the lack of HBGA expression in mantle, dominant GII.4 Sydney strain readily bound to all the oyster tissues, including the digestive tissues, gills, palps, and mantle. In contrast, no binding of the epidemic GII.17 Kawasaki308 VLPs to any of the investigated oyster tissues was observed. In synthetic HBGA and saliva-binding assays, GI.1 reacted with A type, H type, and Leb (Lewis b) HBGAs. GII.4 Sydney VLPs showed a broad binding pattern and interacted with various HBGA types. Compared to GI.1 and GII.4 VLPs, the GII.17 Kawasaki308 VLPs only weakly associated with long-chain saccharides containing A type, B type, H type, and Leb blood group epitopes. Our findings indicate that GI.1 and GII.4 noroviruses are likely to be concentrated in oysters, by binding to HBGA-like glycans, and therefore potentially leading to increased long term transmission. In regards to the GII.17 Kawasaki308 strain, we suggest that oysters can only function as short term transmission vector in periods of high environmental virus concentrations.
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human norovirus interactions with histo blood group antigens and human milk oligosaccharides
Journal of Virology, 2016Co-Authors: Horst Schroten, Franzgeorg Hanisch, Grant S HansmanAbstract:Human noroviruses interact with both human histo-blood group antigens (HBGAs) and human milk oligosaccharides (HMOs). The former are believed to be important for a virus infection, while the latter might act as natural decoys in the host during an infection. However, certain noroviruses are known to bind poorly to HBGAs and yet still cause infections; some interact with numerous HBGA types but are nonprevalent; and yet others bind HBGAs and seem to be increasing in prevalence. HBGAs and HMOs can be found as soluble antigens in humans, can be structurally alike, and can interact with equivalent residues at identical binding pockets on the capsid. In this Gem, we discuss HBGA and HMO binding studies for human noroviruses, concentrating on the clinically important genogroup II noroviruses. In short, the roles of HBGA and HMO interactions in norovirus infections are still unclear.
Grant S Hansman - One of the best experts on this subject based on the ideXlab platform.
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human norovirus neutralized by a monoclonal antibody targeting the histo blood group antigen pocket
Journal of Virology, 2018Co-Authors: Anna D Koromyslova, Vasily Morozov, Lisa Hefele, Grant S HansmanAbstract:Temporal changes in the GII.4 human norovirus capsid sequences occasionally result in the emergence of genetic variants capable of causing new epidemics. The persistence of GII.4 is believed to be associated with the recognition of numerous histo-blood group antigen (HBGA) types and antigenic drift. We found that one of the earliest known GII.4 isolates (in 1974) and a more recent epidemic GII.4 variant (in 2012) had varied norovirus-specific monoclonal antibody (MAb) reactivities but similar HBGA binding profiles. To better understand the binding interaction of one MAb (10E9) that had varied reactivity with these GII.4 variants, we determined the X-ray crystal structure of the NSW-2012 GII.4 P domain 10E9 Fab complex. We showed that the 10E9 Fab interacted with conserved and variable residues, which could be associated with antigenic drift. Interestingly, the 10E9 Fab binding pocket partially overlapped the HBGA pocket and had direct competition for conserved HBGA binding residues (i.e., Arg345 and Tyr444). Indeed, the 10E9 MAb blocked norovirus virus-like particles (VLPs) from binding to several sources of HBGAs. Moreover, the 10E9 antibody completely abolished virus replication in the human norovirus intestinal enteroid cell culture system. Our new findings provide the first direct evidence that competition for GII.4 HBGA binding residues and steric obstruction could lead to norovirus neutralization. On the other hand, the 10E9 MAb recognized residues flanking the HBGA pocket, which are often substituted as the virus evolves. This mechanism of antigenic drift likely influences herd immunity and impedes the possibility of acquiring broadly reactive HBGA-blocking antibodies.IMPORTANCE The emergence of new epidemic GII.4 norovirus variants is thought to be associated with changes in antigenicity and HBGA binding capacity. Here, we show that HBGA binding profiles remain unchanged between the 1974 and 2012 GII.4 variants, whereas these variants showed various levels of reactivity against a panel of GII.4 MAbs. We identified a MAb that bound at the HBGA pocket, blocked norovirus VLPs from binding to HBGAs, and neutralized norovirus virions in the cell culture system. Raised against a GII.4 2006 strain, this MAb was unreactive to a GII.4 1974 isolate but was able to neutralize the newer 2012 strain, which has important implications for vaccine design. Altogether, these new findings suggest that the amino acid variations surrounding the HBGA pocket lead to temporal changes in antigenicity without affecting the ability of GII.4 variants to bind HBGAs, which are known cofactors for infection.
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human norovirus interactions with histo blood group antigens and human milk oligosaccharides
Journal of Virology, 2016Co-Authors: Horst Schroten, Franzgeorg Hanisch, Grant S HansmanAbstract:Human noroviruses interact with both human histo-blood group antigens (HBGAs) and human milk oligosaccharides (HMOs). The former are believed to be important for a virus infection, while the latter might act as natural decoys in the host during an infection. However, certain noroviruses are known to bind poorly to HBGAs and yet still cause infections; some interact with numerous HBGA types but are nonprevalent; and yet others bind HBGAs and seem to be increasing in prevalence. HBGAs and HMOs can be found as soluble antigens in humans, can be structurally alike, and can interact with equivalent residues at identical binding pockets on the capsid. In this Gem, we discuss HBGA and HMO binding studies for human noroviruses, concentrating on the clinically important genogroup II noroviruses. In short, the roles of HBGA and HMO interactions in norovirus infections are still unclear.
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attachment of norovirus to histo blood group antigens a cooperative multistep process
Angewandte Chemie, 2015Co-Authors: Alvaro Mallagaray, Grant S Hansman, Julia Lockhauserbaumer, Charlotte Uetrecht, Thomas PetersAbstract:Human noroviruses recognize histo blood group antigens (HBGAs) as cellular attachment factors. Recently, it has been discovered that norovirus infection can be significantly enhanced by HBGA binding. Yet the attachment process and how it promotes host-cell entry is only poorly understood. The binding of a norovirus protruding (P) domain of a predominant GII.4 Saga strain to HBGAs at atomic resolution was studied. So far, independent and equivalent multiple binding sites were held responsible for attachment. Using NMR experiments we show that norovirus-HBGA binding is a cooperative multi-step process, and native mass spectrometry reveals four instead of two HBGA binding sites per P-dimer. An accompanying crystallographic study has disclosed four instead of two L-fucose binding sites per P-dimer of a related GII.10 strain1 further supporting our findings. We have uncovered a novel paradigm for norovirus-HBGA recognition that will inspire further studies into norovirus-host interactions.
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human noroviruses fondness for histo blood group antigens
Journal of Virology, 2015Co-Authors: Bishal Kumar Singh, Mila M Leuthold, Grant S HansmanAbstract:Human noroviruses are the dominant cause of outbreaks of gastroenteritis around the world. Human noroviruses interact with the polymorphic human histo-blood group antigens (HBGAs), and this interaction is thought to be important for infection. Indeed, synthetic HBGAs or HBGA-expressing enteric bacteria were shown to enhance norovirus infection in B cells. A number of studies have found a possible relationship between HBGA type and norovirus susceptibility. The genogroup II, genotype 4 (GII.4) noroviruses are the dominant cluster, evolve every other year, and are thought to modify their binding interactions with different HBGA types. Here we show high-resolution X-ray crystal structures of the capsid protruding (P) domains from epidemic GII.4 variants from 2004, 2006, and 2012, cocrystallized with a panel of HBGA types (H type 2, Lewis Y, Lewis B, Lewis A, Lewis X, A type, and B type). Many of the HBGA binding interactions were found to be complex, involving capsid loop movements, alternative HBGA conformations, and HBGA rotations. We showed that a loop (residues 391 to 395) was elegantly repositioned to allow for Lewis Y binding. This loop was also slightly shifted to provide direct hydrogen- and water-mediated bonds with Lewis B. We considered that the flexible loop modulated Lewis HBGA binding. The GII.4 noroviruses have dominated outbreaks over the past decade, which may be explained by their exquisite HBGA binding mechanisms, their fondness for Lewis HBGAs, and their temporal amino acid modifications. IMPORTANCE Our data provide a comprehensive picture of GII.4 P domain and HBGA binding interactions. The exceptionally high resolutions of our X-ray crystal structures allowed us to accurately recognize novel GII.4 P domain interactions with numerous HBGA types. We showed that the GII.4 P domain-HBGA interactions involved complex binding mechanisms that were not previously observed in norovirus structural studies. Many of the GII.4 P domain-HBGA interactions we identified were negative in earlier enzyme-linked immunosorbent assay (ELISA)-based studies. Altogether, our data show that the GII.4 norovirus P domains can accommodate numerous HBGA types.
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structural analysis of a rabbit hemorrhagic disease virus binding to histo blood group antigens
Journal of Virology, 2015Co-Authors: Mila M Leuthold, Kevin P Dalton, Grant S HansmanAbstract:Rabbit hemorrhagic disease virus (RHDV) is a member of the Caliciviridae family (Lagovirus genus). RHDV is highly contagious and attaches to epithelial cells in the digestive or respiratory tract, leading to massive lesions with high mortality rates. A new variant of RHDV (termed RHDVb) recently has emerged, and previously vaccinated rabbits appear to have little protection against this new strain. Similar to human norovirus (Caliciviridae, Norovirus genus), RHDV binds histo-blood group antigens (HBGAs), and this is thought to be important for infection. Here, we report the HBGA binding site on the RHDVb capsid-protruding domain (P domain) using X-ray crystallography. The HBGA binding pocket was located in a negatively charged patch on the side of the P domain and at a dimeric interface. Residues from both monomers contributed to the HBGA binding and involved a network of direct hydrogen bonds and water-mediated interactions. An amino acid sequence alignment of different RHDV strains indicated that the residues directly interacting with the ABH-fucose of the HBGAs (Asp472, Asn474, and Ser479) were highly conserved. This result suggested that different RHDV strains also could bind HBGAs at the equivalent pocket. Moreover, several HBGA binding characteristics between RHDVb and human genogroup II norovirus were similar, which indicated a possible convergent evolution of HBGA binding interactions. Further structural studies with other RHDV strains are needed in order to better understand the HBGA binding mechanisms among the diverse RHDV strains. IMPORTANCE We identified, for the first time, the HBGA binding site on an RHDVb P domain using X-ray crystallography. Our results showed that RHDVb and human genogroup II noroviruses had similar HBGA binding interactions. Recently, it was discovered that synthetic HBGAs or HBGA-expressing enteric bacteria could enhance human genogroup II norovirus infection in B cells. Considering that RHDVb and genogroup II norovirus similarly interacted with HBGAs, it may be possible that a comparable cell culture system also could work with RHDVb. Taken together, these new findings will extend our understanding of calicivirus HBGA interactions and may help to elucidate the specific roles of HBGAs in calicivirus infections.
Vasily Morozov - One of the best experts on this subject based on the ideXlab platform.
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human norovirus neutralized by a monoclonal antibody targeting the histo blood group antigen pocket
Journal of Virology, 2018Co-Authors: Anna D Koromyslova, Vasily Morozov, Lisa Hefele, Grant S HansmanAbstract:Temporal changes in the GII.4 human norovirus capsid sequences occasionally result in the emergence of genetic variants capable of causing new epidemics. The persistence of GII.4 is believed to be associated with the recognition of numerous histo-blood group antigen (HBGA) types and antigenic drift. We found that one of the earliest known GII.4 isolates (in 1974) and a more recent epidemic GII.4 variant (in 2012) had varied norovirus-specific monoclonal antibody (MAb) reactivities but similar HBGA binding profiles. To better understand the binding interaction of one MAb (10E9) that had varied reactivity with these GII.4 variants, we determined the X-ray crystal structure of the NSW-2012 GII.4 P domain 10E9 Fab complex. We showed that the 10E9 Fab interacted with conserved and variable residues, which could be associated with antigenic drift. Interestingly, the 10E9 Fab binding pocket partially overlapped the HBGA pocket and had direct competition for conserved HBGA binding residues (i.e., Arg345 and Tyr444). Indeed, the 10E9 MAb blocked norovirus virus-like particles (VLPs) from binding to several sources of HBGAs. Moreover, the 10E9 antibody completely abolished virus replication in the human norovirus intestinal enteroid cell culture system. Our new findings provide the first direct evidence that competition for GII.4 HBGA binding residues and steric obstruction could lead to norovirus neutralization. On the other hand, the 10E9 MAb recognized residues flanking the HBGA pocket, which are often substituted as the virus evolves. This mechanism of antigenic drift likely influences herd immunity and impedes the possibility of acquiring broadly reactive HBGA-blocking antibodies.IMPORTANCE The emergence of new epidemic GII.4 norovirus variants is thought to be associated with changes in antigenicity and HBGA binding capacity. Here, we show that HBGA binding profiles remain unchanged between the 1974 and 2012 GII.4 variants, whereas these variants showed various levels of reactivity against a panel of GII.4 MAbs. We identified a MAb that bound at the HBGA pocket, blocked norovirus VLPs from binding to HBGAs, and neutralized norovirus virions in the cell culture system. Raised against a GII.4 2006 strain, this MAb was unreactive to a GII.4 1974 isolate but was able to neutralize the newer 2012 strain, which has important implications for vaccine design. Altogether, these new findings suggest that the amino acid variations surrounding the HBGA pocket lead to temporal changes in antigenicity without affecting the ability of GII.4 variants to bind HBGAs, which are known cofactors for infection.
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pandemic gii 4 sydney and epidemic gii 17 kawasaki308 noroviruses display distinct specificities for histo blood group antigens leading to different transmission vector dynamics in pacific oysters
Frontiers in Microbiology, 2018Co-Authors: Vasily Morozov, Franzgeorg Hanisch, Mathias K Wegner, Horst SchrotenAbstract:Noroviruses are the major cause of foodborne outbreaks of acute gastroenteritis, which are quiet often linked to raw oyster consumption. Previous studies have suggested histo-blood group antigens (HBGA)-like structures in the oyster tissues as ligands for norovirus binding and persistence. To better understand how oysters can function as vectors for common human noroviruses we have first tested the ability of the GI.1 West Chester, the pandemic GII.4 Sydney, and the epidemic GII.17 Kawasaki308 strains to interact with oyster tissues, and secondly explored how the HBGA preferences of these strains can affect their persistence in oyster tissues. We have found limited HBGA expression in oyster tissues. Only A and H type 1 HBGAs were present in digestive tissues and palps of the Pacific oyster Crassostrea gigas, while gills and mantle lack any HBGA structures. Virus-Like particles (VLPs) of the GI.1 West Chester norovirus reacted with the digestive tissues and palps. Despite of the lack of HBGA expression in mantle, dominant GII.4 Sydney strain readily bound to all the oyster tissues, including digestive tissues, gills, palps, and mantle. In contrast, no binding of the epidemic GII.17 Kawasaki308 VLPs to any oyster tissues was observed. In synthetic HBGA and saliva-binding assays, GI.1 reacted with A type, H type, and Lewis b HBGAs. GII.4 Sydney VLPs showed a broad binding pattern and interacted with various HBGA types, including H type 1 structures. Compared to GI.1 and GII.4 VLPs, the GII.17 Kawasaki308 VLPs only weakly associated with HBGAs carbohydrates and mainly exhibited low affinity binding to long-chain saccharides containing A type, B type, H type, Leb blood group epitopes. Our findings therefore indicate that GI.1 and GII.4 noroviruses are likely to be concentrated in the oysters via HBGA-like glycans potentially leading to increased long term transmission, while for the GII.17 Kawasaki308 strain oysters can only function as short term transmission vectors in periods of high environmental virus concentrations.
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Data_Sheet_1_Pandemic GII.4 Sydney and Epidemic GII.17 Kawasaki308 Noroviruses Display Distinct Specificities for Histo-Blood Group Antigens Leading to Different Transmission Vector Dynamics in Pacific Oysters.docx
2018Co-Authors: Vasily Morozov, Franzgeorg Hanisch, Mathias K Wegner, Horst SchrotenAbstract:Noroviruses are the major cause of foodborne outbreaks of acute gastroenteritis, which are often linked to raw oyster consumption. Previous studies have suggested histo-blood group antigens (HBGA)-like structures in the oyster tissues as ligands for norovirus binding and persistence. To better understand how oysters function as vectors for the most common human noroviruses, we first tested the ability of the norovirus strains GI.1 West Chester, the pandemic GII.4 Sydney, and the epidemic GII.17 Kawasaki308 strains to interact with oyster tissues. Secondly, we explored how the HBGA preferences of these strains can affect their persistence in oyster tissues. We found limited HBGA expression in oyster tissues. HBGAs of A and H type 1 were present in the digestive tissues and palps of the Pacific oyster Crassostrea gigas, while the gills and mantle lacked any HBGA structures. By using Virus-like particles (VLPs), which are antigenically and morphologically similar to native virions, we were able to demonstrate that VLPs of GI.1 West Chester norovirus reacted with the digestive tissues and palps. Despite of the lack of HBGA expression in mantle, dominant GII.4 Sydney strain readily bound to all the oyster tissues, including the digestive tissues, gills, palps, and mantle. In contrast, no binding of the epidemic GII.17 Kawasaki308 VLPs to any of the investigated oyster tissues was observed. In synthetic HBGA and saliva-binding assays, GI.1 reacted with A type, H type, and Leb (Lewis b) HBGAs. GII.4 Sydney VLPs showed a broad binding pattern and interacted with various HBGA types. Compared to GI.1 and GII.4 VLPs, the GII.17 Kawasaki308 VLPs only weakly associated with long-chain saccharides containing A type, B type, H type, and Leb blood group epitopes. Our findings indicate that GI.1 and GII.4 noroviruses are likely to be concentrated in oysters, by binding to HBGA-like glycans, and therefore potentially leading to increased long term transmission. In regards to the GII.17 Kawasaki308 strain, we suggest that oysters can only function as short term transmission vector in periods of high environmental virus concentrations.
Mingyi Bai - One of the best experts on this subject based on the ideXlab platform.
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the bhlh transcription factor hbi1 mediates the trade off between growth and pathogen associated molecular pattern triggered immunity in arabidopsis
The Plant Cell, 2014Co-Authors: Min Fan, Chan Ho Park, Mingyi Bai, Junggun Kim, Tina Wang, Lawrence Chen, Seunghyun Son, Seongki Kim, Mary Beth MudgettAbstract:The trade-off between growth and immunity is crucial for survival in plants. However, the mechanism underlying growth-immunity balance has remained elusive. The PRE-IBH1-HBI1 tripartite helix-loop-helix/basic helix-loop-helix module is part of a central transcription network that mediates growth regulation by several hormonal and environmental signals. Here, genome-wide analyses of HBI1 target genes show that HBI1 regulates both overlapping and unique targets compared with other DNA binding components of the network in Arabidopsis thaliana, supporting a role in specifying network outputs and fine-tuning feedback regulation. Furthermore, HBI1 negatively regulates a subset of genes involved in immunity, and pathogen-associated molecular pattern (PAMP) signals repress HBI1 transcription. Constitutive overexpression and loss-of-function experiments show that HBI1 inhibits PAMP-induced growth arrest, defense gene expression, reactive oxygen species production, and resistance to pathogen. These results show that HBI1, as a component of the central growth regulation circuit, functions as a major node of crosstalk that mediates a trade-off between growth and immunity in plants.
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a triple helix loop helix basic helix loop helix cascade controls cell elongation downstream of multiple hormonal and environmental signaling pathways in arabidopsis
The Plant Cell, 2012Co-Authors: Mingyi Bai, Min Fan, Zhiyong WangAbstract:Environmental and endogenous signals, including light, temperature, brassinosteroid (BR), and gibberellin (GA), regulate cell elongation largely by influencing the expression of the paclobutrazol-resistant (PRE) family helix-loop-helix (HLH) factors, which promote cell elongation by interacting antagonistically with another HLH factor, IBH1. However, the molecular mechanism by which PREs and IBH1 regulate gene expression has remained unknown. Here, we show that IBH1 interacts with and inhibits a DNA binding basic helix-loop-helix (bHLH) protein, HBI1, in Arabidopsis thaliana. Overexpression of HBI1 increased hypocotyl and petiole elongation, whereas dominant inactivation of HBI1 and its homologs caused a dwarf phenotype, indicating that HBI1 is a positive regulator of cell elongation. In vitro and in vivo experiments showed that HBI1 directly bound to the promoters and activated two EXPANSIN genes encoding cell wall–loosening enzymes; HBI1’s DNA binding and transcriptional activities were inhibited by IBH1, but the inhibitory effects of IBH1 were abolished by PRE1. The results indicate that PREs activate the DNA binding bHLH factor HBI1 by sequestering its inhibitor IBH1. Altering each of the three factors affected plant sensitivities to BR, GA, temperature, and light. Our study demonstrates that PREs, IBH1, and HBI1 form a chain of antagonistic switches that regulates cell elongation downstream of multiple external and endogenous signals.
Franzgeorg Hanisch - One of the best experts on this subject based on the ideXlab platform.
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pandemic gii 4 sydney and epidemic gii 17 kawasaki308 noroviruses display distinct specificities for histo blood group antigens leading to different transmission vector dynamics in pacific oysters
Frontiers in Microbiology, 2018Co-Authors: Vasily Morozov, Franzgeorg Hanisch, Mathias K Wegner, Horst SchrotenAbstract:Noroviruses are the major cause of foodborne outbreaks of acute gastroenteritis, which are quiet often linked to raw oyster consumption. Previous studies have suggested histo-blood group antigens (HBGA)-like structures in the oyster tissues as ligands for norovirus binding and persistence. To better understand how oysters can function as vectors for common human noroviruses we have first tested the ability of the GI.1 West Chester, the pandemic GII.4 Sydney, and the epidemic GII.17 Kawasaki308 strains to interact with oyster tissues, and secondly explored how the HBGA preferences of these strains can affect their persistence in oyster tissues. We have found limited HBGA expression in oyster tissues. Only A and H type 1 HBGAs were present in digestive tissues and palps of the Pacific oyster Crassostrea gigas, while gills and mantle lack any HBGA structures. Virus-Like particles (VLPs) of the GI.1 West Chester norovirus reacted with the digestive tissues and palps. Despite of the lack of HBGA expression in mantle, dominant GII.4 Sydney strain readily bound to all the oyster tissues, including digestive tissues, gills, palps, and mantle. In contrast, no binding of the epidemic GII.17 Kawasaki308 VLPs to any oyster tissues was observed. In synthetic HBGA and saliva-binding assays, GI.1 reacted with A type, H type, and Lewis b HBGAs. GII.4 Sydney VLPs showed a broad binding pattern and interacted with various HBGA types, including H type 1 structures. Compared to GI.1 and GII.4 VLPs, the GII.17 Kawasaki308 VLPs only weakly associated with HBGAs carbohydrates and mainly exhibited low affinity binding to long-chain saccharides containing A type, B type, H type, Leb blood group epitopes. Our findings therefore indicate that GI.1 and GII.4 noroviruses are likely to be concentrated in the oysters via HBGA-like glycans potentially leading to increased long term transmission, while for the GII.17 Kawasaki308 strain oysters can only function as short term transmission vectors in periods of high environmental virus concentrations.
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Data_Sheet_1_Pandemic GII.4 Sydney and Epidemic GII.17 Kawasaki308 Noroviruses Display Distinct Specificities for Histo-Blood Group Antigens Leading to Different Transmission Vector Dynamics in Pacific Oysters.docx
2018Co-Authors: Vasily Morozov, Franzgeorg Hanisch, Mathias K Wegner, Horst SchrotenAbstract:Noroviruses are the major cause of foodborne outbreaks of acute gastroenteritis, which are often linked to raw oyster consumption. Previous studies have suggested histo-blood group antigens (HBGA)-like structures in the oyster tissues as ligands for norovirus binding and persistence. To better understand how oysters function as vectors for the most common human noroviruses, we first tested the ability of the norovirus strains GI.1 West Chester, the pandemic GII.4 Sydney, and the epidemic GII.17 Kawasaki308 strains to interact with oyster tissues. Secondly, we explored how the HBGA preferences of these strains can affect their persistence in oyster tissues. We found limited HBGA expression in oyster tissues. HBGAs of A and H type 1 were present in the digestive tissues and palps of the Pacific oyster Crassostrea gigas, while the gills and mantle lacked any HBGA structures. By using Virus-like particles (VLPs), which are antigenically and morphologically similar to native virions, we were able to demonstrate that VLPs of GI.1 West Chester norovirus reacted with the digestive tissues and palps. Despite of the lack of HBGA expression in mantle, dominant GII.4 Sydney strain readily bound to all the oyster tissues, including the digestive tissues, gills, palps, and mantle. In contrast, no binding of the epidemic GII.17 Kawasaki308 VLPs to any of the investigated oyster tissues was observed. In synthetic HBGA and saliva-binding assays, GI.1 reacted with A type, H type, and Leb (Lewis b) HBGAs. GII.4 Sydney VLPs showed a broad binding pattern and interacted with various HBGA types. Compared to GI.1 and GII.4 VLPs, the GII.17 Kawasaki308 VLPs only weakly associated with long-chain saccharides containing A type, B type, H type, and Leb blood group epitopes. Our findings indicate that GI.1 and GII.4 noroviruses are likely to be concentrated in oysters, by binding to HBGA-like glycans, and therefore potentially leading to increased long term transmission. In regards to the GII.17 Kawasaki308 strain, we suggest that oysters can only function as short term transmission vector in periods of high environmental virus concentrations.
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human norovirus interactions with histo blood group antigens and human milk oligosaccharides
Journal of Virology, 2016Co-Authors: Horst Schroten, Franzgeorg Hanisch, Grant S HansmanAbstract:Human noroviruses interact with both human histo-blood group antigens (HBGAs) and human milk oligosaccharides (HMOs). The former are believed to be important for a virus infection, while the latter might act as natural decoys in the host during an infection. However, certain noroviruses are known to bind poorly to HBGAs and yet still cause infections; some interact with numerous HBGA types but are nonprevalent; and yet others bind HBGAs and seem to be increasing in prevalence. HBGAs and HMOs can be found as soluble antigens in humans, can be structurally alike, and can interact with equivalent residues at identical binding pockets on the capsid. In this Gem, we discuss HBGA and HMO binding studies for human noroviruses, concentrating on the clinically important genogroup II noroviruses. In short, the roles of HBGA and HMO interactions in norovirus infections are still unclear.
