The Experts below are selected from a list of 9 Experts worldwide ranked by ideXlab platform

George E O Muscat - One of the best experts on this subject based on the ideXlab platform.

  • expression and cytoplasmic localisation of Deoxyuridine Triphosphate Pyrophosphatase encoded by a human endogenous retrovirus
    Archives of Virology, 2000
    Co-Authors: Jonathan M Harris, E M Mcintosh, George E O Muscat
    Abstract:

    Many lentiviruses encode a dUTPase which may protect against toxic misincorporation of dUTP into cDNA during reverse transcription. However, the primate lentiviruses HIV and SIV do not express a dUTPase. Significantly, the host genomes of these lentiviruses contain a multicopy endogenous retrovirus which is absent in non-primate genomes. In humans, this endogenous retrovirus is known as HERV-K and encodes a potential dUTPase sequence. Previously, we have suggested that HIV infection is complemented by a cytosolic dUTPase derived from the dUTPase gene encoded by HERV-K. This study demonstrates expression of HERV-K dUTPase transcripts and protein in human cell lines using RT-PCR and western blot analysis. Immunocytochemistry showed that HERV-K dUTPase was predominantly located in cell cytoplasm when transiently expressed in COS-1 cells. These data provide substantiation and support for the hypothesis above and is the first documentation of expression of an enzyme of nucleotide metabolism expressed by an endogenous retrovirus.

Jonathan M Harris - One of the best experts on this subject based on the ideXlab platform.

  • expression and cytoplasmic localisation of Deoxyuridine Triphosphate Pyrophosphatase encoded by a human endogenous retrovirus
    Archives of Virology, 2000
    Co-Authors: Jonathan M Harris, E M Mcintosh, George E O Muscat
    Abstract:

    Many lentiviruses encode a dUTPase which may protect against toxic misincorporation of dUTP into cDNA during reverse transcription. However, the primate lentiviruses HIV and SIV do not express a dUTPase. Significantly, the host genomes of these lentiviruses contain a multicopy endogenous retrovirus which is absent in non-primate genomes. In humans, this endogenous retrovirus is known as HERV-K and encodes a potential dUTPase sequence. Previously, we have suggested that HIV infection is complemented by a cytosolic dUTPase derived from the dUTPase gene encoded by HERV-K. This study demonstrates expression of HERV-K dUTPase transcripts and protein in human cell lines using RT-PCR and western blot analysis. Immunocytochemistry showed that HERV-K dUTPase was predominantly located in cell cytoplasm when transiently expressed in COS-1 cells. These data provide substantiation and support for the hypothesis above and is the first documentation of expression of an enzyme of nucleotide metabolism expressed by an endogenous retrovirus.

E M Mcintosh - One of the best experts on this subject based on the ideXlab platform.

  • expression and cytoplasmic localisation of Deoxyuridine Triphosphate Pyrophosphatase encoded by a human endogenous retrovirus
    Archives of Virology, 2000
    Co-Authors: Jonathan M Harris, E M Mcintosh, George E O Muscat
    Abstract:

    Many lentiviruses encode a dUTPase which may protect against toxic misincorporation of dUTP into cDNA during reverse transcription. However, the primate lentiviruses HIV and SIV do not express a dUTPase. Significantly, the host genomes of these lentiviruses contain a multicopy endogenous retrovirus which is absent in non-primate genomes. In humans, this endogenous retrovirus is known as HERV-K and encodes a potential dUTPase sequence. Previously, we have suggested that HIV infection is complemented by a cytosolic dUTPase derived from the dUTPase gene encoded by HERV-K. This study demonstrates expression of HERV-K dUTPase transcripts and protein in human cell lines using RT-PCR and western blot analysis. Immunocytochemistry showed that HERV-K dUTPase was predominantly located in cell cytoplasm when transiently expressed in COS-1 cells. These data provide substantiation and support for the hypothesis above and is the first documentation of expression of an enzyme of nucleotide metabolism expressed by an endogenous retrovirus.

Chantal Abergel - One of the best experts on this subject based on the ideXlab platform.

  • the nucleoside diphosphate kinase from mimivirus a peculiar affinity for deoxypyrimidine nucleotides
    Journal of Bioenergetics and Biomembranes, 2006
    Co-Authors: Sandra Jeudy, Jeanmichel Claverie, Chantal Abergel
    Abstract:

    The first viral Nucleoside Diphosphate Kinase was recently identified in the giant double-stranded DNA virus Acanthamoeba polyphag a Mimivirus (ApM). Here we report its expression and detailed biochemical characterization. NDKapm exhibits unique features such as a shorter Kpn-loop, a structural motif previously reported to be part of the active site and involved in oligomer formation. Enzymatic activity measurements on the recombinant NDKapm revealed its preferential affinity for deoxypyrimidine nucleotides. This property might represent an adaptation of NDKapm to the production of the limiting TTP deoxynucleotide required for the replication of the large A+T rich (72%) viral genome. The NDKapm might also assume a role in dUTP detoxification to compensate for the surprising absence of Mimivirus dUTPase (Deoxyuridine Triphosphate Pyrophosphatase) an important enzyme conserved in most viruses. Although the phylogenetic analysis of NDK sequences sampled through organisms from the three domains of life is only partially informative, it favors an ancestral origin for NDKapm over a recent acquisition from a eukaryotic organism by horizontal gene transfer.

Sandra Jeudy - One of the best experts on this subject based on the ideXlab platform.

  • the nucleoside diphosphate kinase from mimivirus a peculiar affinity for deoxypyrimidine nucleotides
    Journal of Bioenergetics and Biomembranes, 2006
    Co-Authors: Sandra Jeudy, Jeanmichel Claverie, Chantal Abergel
    Abstract:

    The first viral Nucleoside Diphosphate Kinase was recently identified in the giant double-stranded DNA virus Acanthamoeba polyphag a Mimivirus (ApM). Here we report its expression and detailed biochemical characterization. NDKapm exhibits unique features such as a shorter Kpn-loop, a structural motif previously reported to be part of the active site and involved in oligomer formation. Enzymatic activity measurements on the recombinant NDKapm revealed its preferential affinity for deoxypyrimidine nucleotides. This property might represent an adaptation of NDKapm to the production of the limiting TTP deoxynucleotide required for the replication of the large A+T rich (72%) viral genome. The NDKapm might also assume a role in dUTP detoxification to compensate for the surprising absence of Mimivirus dUTPase (Deoxyuridine Triphosphate Pyrophosphatase) an important enzyme conserved in most viruses. Although the phylogenetic analysis of NDK sequences sampled through organisms from the three domains of life is only partially informative, it favors an ancestral origin for NDKapm over a recent acquisition from a eukaryotic organism by horizontal gene transfer.