The Experts below are selected from a list of 68400 Experts worldwide ranked by ideXlab platform
Bruno Canard - One of the best experts on this subject based on the ideXlab platform.
-
crystal structure and activity of kunjin virus ns3 helicase protease and helicase domain assembly in the full length ns3 protein
Journal of Molecular Biology, 2007Co-Authors: E. Mastrangelo, Barbara Selisko, Michela Bollati, M. Milani, P. V. Konarev, Frederic Peyrane, V Pandini, Graziella Sorrentino, Bruno Canard, Dmitri I SvergunAbstract:Flaviviral NS3 is a multifunctional protein displaying N-terminal protease activity in addition to C-terminal helicase, nucleoside 5'-triphosphatase (NTPase), and 5'-terminal RNA triphosphatase (RTPase) activities. NS3 is held to support the separation of RNA daughter and template strands during viral replication. In addition, NS3 assists the initiation of replication by unwinding the RNA secondary structure in the 3' non-translated region (NTR). We report here the three-dimensional structure (at 3.1 angstrom resolution) of the NS3 helicase domain (residues 186-619; NS3:186-619) from Kunjin virus, an Australian variant of the West Nile virus. As for homologous helicases, NS3:186-619 is composed of three domains, two of which are structurally related and held to host the NTPase and RTPase active sites. The third domain (C-terminal) is involved in RNA binding/ recognition. The NS3:186-619 construct occurs as a dimer in solution and in the crystals. We show that NS3:186-619 displays both ATPase and RTPase activities, that it can unwind a double-stranded RNA substrate, being however inactive on a double-stranded DNA substrate. Analysis of different constructs shows that full length NS3 displays increased helicase activity, suggesting that the protease domain plays an assisting role in the RNA unwinding process. The structural interaction between the helicase and protease domain has been assessed using small angle X-ray scattering on full length NS3, disclosing that the protease and helicase domains build a rather elongated molecular assembly differing from that observed in the NS3 protein from hepatitis C virus. (C) 2007 Elsevier Ltd. All rights reserved.
-
the rna helicase nucleotide 5 triphosphatase and rna 5 triphosphatase activities of dengue virus protein ns3 are mg2 dependent and require a functional walker b motif in the helicase catalytic core
Virology, 2004Co-Authors: Delphine Benarroch, Barbara Selisko, Giada A Locatelli, Giovanni Maga, Jeanlouis Romette, Bruno CanardAbstract:Abstract The nonstructural protein 3 (NS3) of Dengue virus (DV) is a multifunctional enzyme carrying activities involved in viral RNA replication and capping: helicase, nucleoside 5′-triphosphatase (NTPase), and RNA 5′-triphosphatase (RTPase). Here, a 54-kDa C-terminal domain of NS3 (ΔNS3) bearing all three activities was expressed as a recombinant protein. Structure-based sequence analysis in comparison with Hepatitis C virus (HCV) helicase indicates the presence of a HCV-helicase-like catalytic core domain in the N-terminal part of ΔNS3, whereas the C-terminal part seems to be different. In this report, we show that the RTPase activity of ΔNS3 is Mg 2+ -dependent as are both helicase and NTPase activities. Mutational analysis shows that the RTPase activity requires an intact NTPase/helicase Walker B motif in the helicase core, consistent with the fact that such motifs are involved in the coordination of Mg 2+ . The R513A substitution in the C-terminal domain of ΔNS3 abrogates helicase activity and strongly diminishes RTPase activity, indicating that both activities are functionally coupled. DV RTPase seems to belong to a new class of Mg 2+ -dependent RTPases, which use the active center of the helicase/NTPase catalytic core in conjunction with elements in the C-terminal domain.
-
the rna helicase nucleotide 5 triphosphatase and rna 5 triphosphatase activities of dengue virus protein ns3 are mg2 dependent and require a functional walker b motif in the helicase catalytic core
Virology, 2004Co-Authors: Delphine Benarroch, Barbara Selisko, Giada A Locatelli, Giovanni Maga, Jeanlouis Romette, Bruno CanardAbstract:The nonstructural protein 3 (NS3) of Dengue virus (DV) is a multifunctional enzyme carrying activities involved in viral RNA replication and capping: helicase, nucleoside 5'-triphosphatase (NTPase), and RNA 5'-triphosphatase (RTPase). Here, a 54-kDa C-terminal domain of NS3 (DeltaNS3) bearing all three activities was expressed as a recombinant protein. Structure-based sequence analysis in comparison with Hepatitis C virus (HCV) helicase indicates the presence of a HCV-helicase-like catalytic core domain in the N-terminal part of DeltaNS3, whereas the C-terminal part seems to be different. In this report, we show that the RTPase activity of DeltaNS3 is Mg2+-dependent as are both helicase and NTPase activities. Mutational analysis shows that the RTPase activity requires an intact NTPase/helicase Walker B motif in the helicase core, consistent with the fact that such motifs are involved in the coordination of Mg2+. The R513A substitution in the C-terminal domain of DeltaNS3 abrogates helicase activity and strongly diminishes RTPase activity, indicating that both activities are functionally coupled. DV RTPase seems to belong to a new class of Mg2+-dependent RTPases, which use the active center of the helicase/NTPase catalytic core in conjunction with elements in the C-terminal domain.
Barbara Selisko - One of the best experts on this subject based on the ideXlab platform.
-
crystal structure and activity of kunjin virus ns3 helicase protease and helicase domain assembly in the full length ns3 protein
Journal of Molecular Biology, 2007Co-Authors: E. Mastrangelo, Barbara Selisko, Michela Bollati, M. Milani, P. V. Konarev, Frederic Peyrane, V Pandini, Graziella Sorrentino, Bruno Canard, Dmitri I SvergunAbstract:Flaviviral NS3 is a multifunctional protein displaying N-terminal protease activity in addition to C-terminal helicase, nucleoside 5'-triphosphatase (NTPase), and 5'-terminal RNA triphosphatase (RTPase) activities. NS3 is held to support the separation of RNA daughter and template strands during viral replication. In addition, NS3 assists the initiation of replication by unwinding the RNA secondary structure in the 3' non-translated region (NTR). We report here the three-dimensional structure (at 3.1 angstrom resolution) of the NS3 helicase domain (residues 186-619; NS3:186-619) from Kunjin virus, an Australian variant of the West Nile virus. As for homologous helicases, NS3:186-619 is composed of three domains, two of which are structurally related and held to host the NTPase and RTPase active sites. The third domain (C-terminal) is involved in RNA binding/ recognition. The NS3:186-619 construct occurs as a dimer in solution and in the crystals. We show that NS3:186-619 displays both ATPase and RTPase activities, that it can unwind a double-stranded RNA substrate, being however inactive on a double-stranded DNA substrate. Analysis of different constructs shows that full length NS3 displays increased helicase activity, suggesting that the protease domain plays an assisting role in the RNA unwinding process. The structural interaction between the helicase and protease domain has been assessed using small angle X-ray scattering on full length NS3, disclosing that the protease and helicase domains build a rather elongated molecular assembly differing from that observed in the NS3 protein from hepatitis C virus. (C) 2007 Elsevier Ltd. All rights reserved.
-
the rna helicase nucleotide 5 triphosphatase and rna 5 triphosphatase activities of dengue virus protein ns3 are mg2 dependent and require a functional walker b motif in the helicase catalytic core
Virology, 2004Co-Authors: Delphine Benarroch, Barbara Selisko, Giada A Locatelli, Giovanni Maga, Jeanlouis Romette, Bruno CanardAbstract:Abstract The nonstructural protein 3 (NS3) of Dengue virus (DV) is a multifunctional enzyme carrying activities involved in viral RNA replication and capping: helicase, nucleoside 5′-triphosphatase (NTPase), and RNA 5′-triphosphatase (RTPase). Here, a 54-kDa C-terminal domain of NS3 (ΔNS3) bearing all three activities was expressed as a recombinant protein. Structure-based sequence analysis in comparison with Hepatitis C virus (HCV) helicase indicates the presence of a HCV-helicase-like catalytic core domain in the N-terminal part of ΔNS3, whereas the C-terminal part seems to be different. In this report, we show that the RTPase activity of ΔNS3 is Mg 2+ -dependent as are both helicase and NTPase activities. Mutational analysis shows that the RTPase activity requires an intact NTPase/helicase Walker B motif in the helicase core, consistent with the fact that such motifs are involved in the coordination of Mg 2+ . The R513A substitution in the C-terminal domain of ΔNS3 abrogates helicase activity and strongly diminishes RTPase activity, indicating that both activities are functionally coupled. DV RTPase seems to belong to a new class of Mg 2+ -dependent RTPases, which use the active center of the helicase/NTPase catalytic core in conjunction with elements in the C-terminal domain.
-
the rna helicase nucleotide 5 triphosphatase and rna 5 triphosphatase activities of dengue virus protein ns3 are mg2 dependent and require a functional walker b motif in the helicase catalytic core
Virology, 2004Co-Authors: Delphine Benarroch, Barbara Selisko, Giada A Locatelli, Giovanni Maga, Jeanlouis Romette, Bruno CanardAbstract:The nonstructural protein 3 (NS3) of Dengue virus (DV) is a multifunctional enzyme carrying activities involved in viral RNA replication and capping: helicase, nucleoside 5'-triphosphatase (NTPase), and RNA 5'-triphosphatase (RTPase). Here, a 54-kDa C-terminal domain of NS3 (DeltaNS3) bearing all three activities was expressed as a recombinant protein. Structure-based sequence analysis in comparison with Hepatitis C virus (HCV) helicase indicates the presence of a HCV-helicase-like catalytic core domain in the N-terminal part of DeltaNS3, whereas the C-terminal part seems to be different. In this report, we show that the RTPase activity of DeltaNS3 is Mg2+-dependent as are both helicase and NTPase activities. Mutational analysis shows that the RTPase activity requires an intact NTPase/helicase Walker B motif in the helicase core, consistent with the fact that such motifs are involved in the coordination of Mg2+. The R513A substitution in the C-terminal domain of DeltaNS3 abrogates helicase activity and strongly diminishes RTPase activity, indicating that both activities are functionally coupled. DV RTPase seems to belong to a new class of Mg2+-dependent RTPases, which use the active center of the helicase/NTPase catalytic core in conjunction with elements in the C-terminal domain.
Delphine Benarroch - One of the best experts on this subject based on the ideXlab platform.
-
the rna helicase nucleotide 5 triphosphatase and rna 5 triphosphatase activities of dengue virus protein ns3 are mg2 dependent and require a functional walker b motif in the helicase catalytic core
Virology, 2004Co-Authors: Delphine Benarroch, Barbara Selisko, Giada A Locatelli, Giovanni Maga, Jeanlouis Romette, Bruno CanardAbstract:Abstract The nonstructural protein 3 (NS3) of Dengue virus (DV) is a multifunctional enzyme carrying activities involved in viral RNA replication and capping: helicase, nucleoside 5′-triphosphatase (NTPase), and RNA 5′-triphosphatase (RTPase). Here, a 54-kDa C-terminal domain of NS3 (ΔNS3) bearing all three activities was expressed as a recombinant protein. Structure-based sequence analysis in comparison with Hepatitis C virus (HCV) helicase indicates the presence of a HCV-helicase-like catalytic core domain in the N-terminal part of ΔNS3, whereas the C-terminal part seems to be different. In this report, we show that the RTPase activity of ΔNS3 is Mg 2+ -dependent as are both helicase and NTPase activities. Mutational analysis shows that the RTPase activity requires an intact NTPase/helicase Walker B motif in the helicase core, consistent with the fact that such motifs are involved in the coordination of Mg 2+ . The R513A substitution in the C-terminal domain of ΔNS3 abrogates helicase activity and strongly diminishes RTPase activity, indicating that both activities are functionally coupled. DV RTPase seems to belong to a new class of Mg 2+ -dependent RTPases, which use the active center of the helicase/NTPase catalytic core in conjunction with elements in the C-terminal domain.
-
the rna helicase nucleotide 5 triphosphatase and rna 5 triphosphatase activities of dengue virus protein ns3 are mg2 dependent and require a functional walker b motif in the helicase catalytic core
Virology, 2004Co-Authors: Delphine Benarroch, Barbara Selisko, Giada A Locatelli, Giovanni Maga, Jeanlouis Romette, Bruno CanardAbstract:The nonstructural protein 3 (NS3) of Dengue virus (DV) is a multifunctional enzyme carrying activities involved in viral RNA replication and capping: helicase, nucleoside 5'-triphosphatase (NTPase), and RNA 5'-triphosphatase (RTPase). Here, a 54-kDa C-terminal domain of NS3 (DeltaNS3) bearing all three activities was expressed as a recombinant protein. Structure-based sequence analysis in comparison with Hepatitis C virus (HCV) helicase indicates the presence of a HCV-helicase-like catalytic core domain in the N-terminal part of DeltaNS3, whereas the C-terminal part seems to be different. In this report, we show that the RTPase activity of DeltaNS3 is Mg2+-dependent as are both helicase and NTPase activities. Mutational analysis shows that the RTPase activity requires an intact NTPase/helicase Walker B motif in the helicase core, consistent with the fact that such motifs are involved in the coordination of Mg2+. The R513A substitution in the C-terminal domain of DeltaNS3 abrogates helicase activity and strongly diminishes RTPase activity, indicating that both activities are functionally coupled. DV RTPase seems to belong to a new class of Mg2+-dependent RTPases, which use the active center of the helicase/NTPase catalytic core in conjunction with elements in the C-terminal domain.
Dmitri I Svergun - One of the best experts on this subject based on the ideXlab platform.
-
crystal structure and activity of kunjin virus ns3 helicase protease and helicase domain assembly in the full length ns3 protein
Journal of Molecular Biology, 2007Co-Authors: E. Mastrangelo, Barbara Selisko, Michela Bollati, M. Milani, P. V. Konarev, Frederic Peyrane, V Pandini, Graziella Sorrentino, Bruno Canard, Dmitri I SvergunAbstract:Flaviviral NS3 is a multifunctional protein displaying N-terminal protease activity in addition to C-terminal helicase, nucleoside 5'-triphosphatase (NTPase), and 5'-terminal RNA triphosphatase (RTPase) activities. NS3 is held to support the separation of RNA daughter and template strands during viral replication. In addition, NS3 assists the initiation of replication by unwinding the RNA secondary structure in the 3' non-translated region (NTR). We report here the three-dimensional structure (at 3.1 angstrom resolution) of the NS3 helicase domain (residues 186-619; NS3:186-619) from Kunjin virus, an Australian variant of the West Nile virus. As for homologous helicases, NS3:186-619 is composed of three domains, two of which are structurally related and held to host the NTPase and RTPase active sites. The third domain (C-terminal) is involved in RNA binding/ recognition. The NS3:186-619 construct occurs as a dimer in solution and in the crystals. We show that NS3:186-619 displays both ATPase and RTPase activities, that it can unwind a double-stranded RNA substrate, being however inactive on a double-stranded DNA substrate. Analysis of different constructs shows that full length NS3 displays increased helicase activity, suggesting that the protease domain plays an assisting role in the RNA unwinding process. The structural interaction between the helicase and protease domain has been assessed using small angle X-ray scattering on full length NS3, disclosing that the protease and helicase domains build a rather elongated molecular assembly differing from that observed in the NS3 protein from hepatitis C virus. (C) 2007 Elsevier Ltd. All rights reserved.
E. Mastrangelo - One of the best experts on this subject based on the ideXlab platform.
-
Crystal Structure and Activity Of Kunjin Virus Ns3 Helicase; Protease and Helicase Domain Assembly in the Full Length Ns3 Protein
2015Co-Authors: M. Milani, E. Mastrangelo, P. V. Konarev, D. Svergun, M. BolognesiAbstract:Flaviviral NS3 is a multifunctional protein displaying N-terminal protease activity in addition to C-terminal helicase, nucleoside 5’-transferase (NTPase), and 5’-terminal RNA triphosphatase (RTPase) activities. NS3 is held to support the separation of RNA daughter and template strands during viral replication. We solved the three-dimensional structure (at 3.1 Å resolution) of the NS3 helicase domain (residues 186-619; NS3:186-619) from Kunjin virus, an Australian variant of the West Nile virus (1). We showed that NS3:186-619 displays both ATPase and RTPase activity, that it can unwind a double-stranded RNA substrate, being however inactive on a double-stranded DNA substrate. Analysis of different constructs shows that full length NS3 displays increased helicase activity, suggesting that the protease domain plays an assisting role in the RNA unwinding process. The structural interaction between the helicase and protease domain has been assessed using small angle X-ray scattering on full length NS3, disclosing that the protease and helicase domains build a rather elongated molecular assembly differing from that observed in the NS3 protein from hepatitis C virus. S.A.X.S. data were collected on the X33 camera of the EMBL on the storage ring DORI
-
crystal structure and activity of kunjin virus ns3 helicase protease and helicase domain assembly in the full length ns3 protein
Journal of Molecular Biology, 2007Co-Authors: E. Mastrangelo, Barbara Selisko, Michela Bollati, M. Milani, P. V. Konarev, Frederic Peyrane, V Pandini, Graziella Sorrentino, Bruno Canard, Dmitri I SvergunAbstract:Flaviviral NS3 is a multifunctional protein displaying N-terminal protease activity in addition to C-terminal helicase, nucleoside 5'-triphosphatase (NTPase), and 5'-terminal RNA triphosphatase (RTPase) activities. NS3 is held to support the separation of RNA daughter and template strands during viral replication. In addition, NS3 assists the initiation of replication by unwinding the RNA secondary structure in the 3' non-translated region (NTR). We report here the three-dimensional structure (at 3.1 angstrom resolution) of the NS3 helicase domain (residues 186-619; NS3:186-619) from Kunjin virus, an Australian variant of the West Nile virus. As for homologous helicases, NS3:186-619 is composed of three domains, two of which are structurally related and held to host the NTPase and RTPase active sites. The third domain (C-terminal) is involved in RNA binding/ recognition. The NS3:186-619 construct occurs as a dimer in solution and in the crystals. We show that NS3:186-619 displays both ATPase and RTPase activities, that it can unwind a double-stranded RNA substrate, being however inactive on a double-stranded DNA substrate. Analysis of different constructs shows that full length NS3 displays increased helicase activity, suggesting that the protease domain plays an assisting role in the RNA unwinding process. The structural interaction between the helicase and protease domain has been assessed using small angle X-ray scattering on full length NS3, disclosing that the protease and helicase domains build a rather elongated molecular assembly differing from that observed in the NS3 protein from hepatitis C virus. (C) 2007 Elsevier Ltd. All rights reserved.
