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Michael Feiss - One of the best experts on this subject based on the ideXlab platform.
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mechanisms of dna packaging by large double stranded dna viruses
Annual Review of Virology, 2015Co-Authors: Michael FeissAbstract:Translocation of viral double-stranded DNA (dsDNA) into the icosahedral prohead shell is catalyzed by TerL, a motor protein that has ATPase, endonuclease, and translocase activities. TerL, following endonucleolytic cleavage of immature viral DNA Concatemer recognized by TerS, assembles into a pentameric ring motor on the prohead's portal vertex and uses ATP hydrolysis energy for DNA translocation. TerL's N-terminal ATPase is connected by a hinge to the C-terminal endonuclease. Inchworm models propose that modest domain motions accompanying ATP hydrolysis are amplified, through changes in electrostatic interactions, into larger movements of the C-terminal domain bound to DNA. In phage ϕ29, four of the five TerL subunits sequentially hydrolyze ATP, each powering translocation of 2.5 bp. After one viral genome is encapsidated, the internal pressure signals termination of packaging and ejection of the motor. Current focus is on the structures of packaging complexes and the dynamics of TerL during DNA packagin...
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mechanisms of dna packaging by large double stranded dna viruses
Annual Review of Virology, 2015Co-Authors: Venigalla B. Rao, Michael FeissAbstract:Translocation of viral double-stranded DNA (dsDNA) into the icosahedral prohead shell is catalyzed by TerL, a motor protein that has ATPase, endonuclease, and translocase activities. TerL, following endonucleolytic cleavage of immature viral DNA Concatemer recognized by TerS, assembles into a pentameric ring motor on the prohead's portal vertex and uses ATP hydrolysis energy for DNA translocation. TerL's N-terminal ATPase is connected by a hinge to the C-terminal endonuclease. Inchworm models propose that modest domain motions accompanying ATP hydrolysis are amplified, through changes in electrostatic interactions, into larger movements of the C-terminal domain bound to DNA. In phage ϕ29, four of the five TerL subunits sequentially hydrolyze ATP, each powering translocation of 2.5 bp. After one viral genome is encapsidated, the internal pressure signals termination of packaging and ejection of the motor. Current focus is on the structures of packaging complexes and the dynamics of TerL during DNA packaging, endonuclease regulation, and motor mechanics.
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the bacteriophage dna packaging motor
Annual Review of Genetics, 2008Co-Authors: Venigalla B. Rao, Michael FeissAbstract:An ATP-powered DNA translocation machine encapsidates the viral genome in the large dsDNA bacteriophages. The essential components include the empty shell, prohead, and the packaging enzyme, terminase. During translocation, terminase is docked on the prohead's portal protein. The translocation ATPase and the Concatemer-cutting endonuclease reside in terminase. Remarkably, terminases, portal proteins, and shells of tailed bacteriophages and herpes viruses show conserved features. These DNA viruses may have descended from a common ancestor. Terminase's ATPase consists of a classic nucleotide binding fold, most closely resembling that of monomeric helicases. Intriguing models have been proposed for the mechanism of dsDNA translocation, invoking ATP hydrolysis-driven conformational changes of portal or terminase powering DNA motion. Single-molecule studies show that the packaging motor is fast and powerful. Recent advances permit experiments that can critically test the packaging models. The viral genome tran...
Peter P C Mertens - One of the best experts on this subject based on the ideXlab platform.
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rna segment 9 exists as a duplex Concatemer in an australian strain of epizootic haemorrhagic disease virus ehdv genetic analysis and evidence for the presence of Concatemers as a normal feature of orbivirus replication
Virology, 2011Co-Authors: Simon J Anthony, Karin E Darpel, Manjunatha N Belaganahalli, Narender S Maan, Kyriaki Nomikou, G Sutton, Houssam Attoui, Sushila Maan, Peter P C MertensAbstract:abstract Article history:Received 14 July 2011Returned to author for revision11 August 2011Accepted 12 September 2011Available online 2 October 2011Keywords:ConcatemerOrbivirusBTVBluetongue virusEHDVEpizootic hemorrhagic disease virusGene duplicationdsRNA This paper reports a Concatemeric RNA in a strain of epizootic haemorrhagic disease virus (EHDV) serotype 5.Sequencing showed that the Concatemeric RNA contains two identical full-length copies of genome segment9, arranged in series, which has apparently replaced the monomeric form of the segment. In vitro translationdemonstrated that the Concatemeric RNA can act as a viable template for VP6 translation, but that no double-sized protein is produced. Studies were also performed to assess whether mutations might be easily intro-duced into the second copy (which might indicate some potential evolutionary significance of a ConcatemericRNA segment), however multiple (n=40) passages generated no changes in the sequence of either the up-stream or downstream segments. Further, we present results that demonstrate the presence of Concatemersor partial gene duplications in multiple segments of different orbiviruses (in tissue culture and purifiedvirus), suggesting their generation is likely to be a normal feature of orbivirus replication.© 2011 Elsevier Inc. All rights reserved.
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rna segment 9 exists as a duplex Concatemer in an australian strain of epizootic haemorrhagic disease virus ehdv genetic analysis and evidence for the presence of Concatemers as a normal feature of orbivirus replication
Virology, 2011Co-Authors: Simon J Anthony, Karin E Darpel, Manjunatha N Belaganahalli, Narender S Maan, Kyriaki Nomikou, G Sutton, Houssam Attoui, Sushila Maan, Peter P C MertensAbstract:This paper reports a Concatemeric RNA in a strain of epizootic haemorrhagic disease virus (EHDV) serotype 5. Sequencing showed that the Concatemeric RNA contains two identical full-length copies of genome segment 9, arranged in series, which has apparently replaced the monomeric form of the segment. In vitro translation demonstrated that the Concatemeric RNA can act as a viable template for VP6 translation, but that no double-sized protein is produced. Studies were also performed to assess whether mutations might be easily introduced into the second copy (which might indicate some potential evolutionary significance of a Concatemeric RNA segment), however multiple (n=40) passages generated no changes in the sequence of either the upstream or downstream segments. Further, we present results that demonstrate the presence of Concatemers or partial gene duplications in multiple segments of different orbiviruses (in tissue culture and purified virus), suggesting their generation is likely to be a normal feature of orbivirus replication.
Simon J Anthony - One of the best experts on this subject based on the ideXlab platform.
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rna segment 9 exists as a duplex Concatemer in an australian strain of epizootic haemorrhagic disease virus ehdv genetic analysis and evidence for the presence of Concatemers as a normal feature of orbivirus replication
Virology, 2011Co-Authors: Simon J Anthony, Karin E Darpel, Manjunatha N Belaganahalli, Narender S Maan, Kyriaki Nomikou, G Sutton, Houssam Attoui, Sushila Maan, Peter P C MertensAbstract:abstract Article history:Received 14 July 2011Returned to author for revision11 August 2011Accepted 12 September 2011Available online 2 October 2011Keywords:ConcatemerOrbivirusBTVBluetongue virusEHDVEpizootic hemorrhagic disease virusGene duplicationdsRNA This paper reports a Concatemeric RNA in a strain of epizootic haemorrhagic disease virus (EHDV) serotype 5.Sequencing showed that the Concatemeric RNA contains two identical full-length copies of genome segment9, arranged in series, which has apparently replaced the monomeric form of the segment. In vitro translationdemonstrated that the Concatemeric RNA can act as a viable template for VP6 translation, but that no double-sized protein is produced. Studies were also performed to assess whether mutations might be easily intro-duced into the second copy (which might indicate some potential evolutionary significance of a ConcatemericRNA segment), however multiple (n=40) passages generated no changes in the sequence of either the up-stream or downstream segments. Further, we present results that demonstrate the presence of Concatemersor partial gene duplications in multiple segments of different orbiviruses (in tissue culture and purifiedvirus), suggesting their generation is likely to be a normal feature of orbivirus replication.© 2011 Elsevier Inc. All rights reserved.
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rna segment 9 exists as a duplex Concatemer in an australian strain of epizootic haemorrhagic disease virus ehdv genetic analysis and evidence for the presence of Concatemers as a normal feature of orbivirus replication
Virology, 2011Co-Authors: Simon J Anthony, Karin E Darpel, Manjunatha N Belaganahalli, Narender S Maan, Kyriaki Nomikou, G Sutton, Houssam Attoui, Sushila Maan, Peter P C MertensAbstract:This paper reports a Concatemeric RNA in a strain of epizootic haemorrhagic disease virus (EHDV) serotype 5. Sequencing showed that the Concatemeric RNA contains two identical full-length copies of genome segment 9, arranged in series, which has apparently replaced the monomeric form of the segment. In vitro translation demonstrated that the Concatemeric RNA can act as a viable template for VP6 translation, but that no double-sized protein is produced. Studies were also performed to assess whether mutations might be easily introduced into the second copy (which might indicate some potential evolutionary significance of a Concatemeric RNA segment), however multiple (n=40) passages generated no changes in the sequence of either the upstream or downstream segments. Further, we present results that demonstrate the presence of Concatemers or partial gene duplications in multiple segments of different orbiviruses (in tissue culture and purified virus), suggesting their generation is likely to be a normal feature of orbivirus replication.
Venigalla B. Rao - One of the best experts on this subject based on the ideXlab platform.
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mechanisms of dna packaging by large double stranded dna viruses
Annual Review of Virology, 2015Co-Authors: Venigalla B. Rao, Michael FeissAbstract:Translocation of viral double-stranded DNA (dsDNA) into the icosahedral prohead shell is catalyzed by TerL, a motor protein that has ATPase, endonuclease, and translocase activities. TerL, following endonucleolytic cleavage of immature viral DNA Concatemer recognized by TerS, assembles into a pentameric ring motor on the prohead's portal vertex and uses ATP hydrolysis energy for DNA translocation. TerL's N-terminal ATPase is connected by a hinge to the C-terminal endonuclease. Inchworm models propose that modest domain motions accompanying ATP hydrolysis are amplified, through changes in electrostatic interactions, into larger movements of the C-terminal domain bound to DNA. In phage ϕ29, four of the five TerL subunits sequentially hydrolyze ATP, each powering translocation of 2.5 bp. After one viral genome is encapsidated, the internal pressure signals termination of packaging and ejection of the motor. Current focus is on the structures of packaging complexes and the dynamics of TerL during DNA packaging, endonuclease regulation, and motor mechanics.
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the bacteriophage dna packaging motor
Annual Review of Genetics, 2008Co-Authors: Venigalla B. Rao, Michael FeissAbstract:An ATP-powered DNA translocation machine encapsidates the viral genome in the large dsDNA bacteriophages. The essential components include the empty shell, prohead, and the packaging enzyme, terminase. During translocation, terminase is docked on the prohead's portal protein. The translocation ATPase and the Concatemer-cutting endonuclease reside in terminase. Remarkably, terminases, portal proteins, and shells of tailed bacteriophages and herpes viruses show conserved features. These DNA viruses may have descended from a common ancestor. Terminase's ATPase consists of a classic nucleotide binding fold, most closely resembling that of monomeric helicases. Intriguing models have been proposed for the mechanism of dsDNA translocation, invoking ATP hydrolysis-driven conformational changes of portal or terminase powering DNA motion. Single-molecule studies show that the packaging motor is fast and powerful. Recent advances permit experiments that can critically test the packaging models. The viral genome tran...
Narender S Maan - One of the best experts on this subject based on the ideXlab platform.
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rna segment 9 exists as a duplex Concatemer in an australian strain of epizootic haemorrhagic disease virus ehdv genetic analysis and evidence for the presence of Concatemers as a normal feature of orbivirus replication
Virology, 2011Co-Authors: Simon J Anthony, Karin E Darpel, Manjunatha N Belaganahalli, Narender S Maan, Kyriaki Nomikou, G Sutton, Houssam Attoui, Sushila Maan, Peter P C MertensAbstract:abstract Article history:Received 14 July 2011Returned to author for revision11 August 2011Accepted 12 September 2011Available online 2 October 2011Keywords:ConcatemerOrbivirusBTVBluetongue virusEHDVEpizootic hemorrhagic disease virusGene duplicationdsRNA This paper reports a Concatemeric RNA in a strain of epizootic haemorrhagic disease virus (EHDV) serotype 5.Sequencing showed that the Concatemeric RNA contains two identical full-length copies of genome segment9, arranged in series, which has apparently replaced the monomeric form of the segment. In vitro translationdemonstrated that the Concatemeric RNA can act as a viable template for VP6 translation, but that no double-sized protein is produced. Studies were also performed to assess whether mutations might be easily intro-duced into the second copy (which might indicate some potential evolutionary significance of a ConcatemericRNA segment), however multiple (n=40) passages generated no changes in the sequence of either the up-stream or downstream segments. Further, we present results that demonstrate the presence of Concatemersor partial gene duplications in multiple segments of different orbiviruses (in tissue culture and purifiedvirus), suggesting their generation is likely to be a normal feature of orbivirus replication.© 2011 Elsevier Inc. All rights reserved.
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rna segment 9 exists as a duplex Concatemer in an australian strain of epizootic haemorrhagic disease virus ehdv genetic analysis and evidence for the presence of Concatemers as a normal feature of orbivirus replication
Virology, 2011Co-Authors: Simon J Anthony, Karin E Darpel, Manjunatha N Belaganahalli, Narender S Maan, Kyriaki Nomikou, G Sutton, Houssam Attoui, Sushila Maan, Peter P C MertensAbstract:This paper reports a Concatemeric RNA in a strain of epizootic haemorrhagic disease virus (EHDV) serotype 5. Sequencing showed that the Concatemeric RNA contains two identical full-length copies of genome segment 9, arranged in series, which has apparently replaced the monomeric form of the segment. In vitro translation demonstrated that the Concatemeric RNA can act as a viable template for VP6 translation, but that no double-sized protein is produced. Studies were also performed to assess whether mutations might be easily introduced into the second copy (which might indicate some potential evolutionary significance of a Concatemeric RNA segment), however multiple (n=40) passages generated no changes in the sequence of either the upstream or downstream segments. Further, we present results that demonstrate the presence of Concatemers or partial gene duplications in multiple segments of different orbiviruses (in tissue culture and purified virus), suggesting their generation is likely to be a normal feature of orbivirus replication.