Ubiquitin-Conjugating Enzyme

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Peter D Nagy - One of the best experts on this subject based on the ideXlab platform.

  • cellular ubc2 rad6 e2 ubiquitin conjugating Enzyme facilitates tombusvirus replication in yeast and plants
    Virology, 2015
    Co-Authors: Yoshiyuki Imura, Melissa Molho, Chingkai Chuang, Peter D Nagy
    Abstract:

    Mono- and multi-ubiquitination alters the functions and subcellular localization of many cellular and viral proteins. Viruses can co-opt or actively manipulate the ubiquitin network to support viral processes or suppress innate immunity. Using yeast (Saccharomyces cerevisiae) model host, we show that the yeast Rad6p (radiation sensitive 6) E2 Ubiquitin-Conjugating Enzyme and its plant ortholog, AtUbc2, interact with two tombusviral replication proteins and these E2 Ubiquitin-Conjugating Enzymes could be co-purified with the tombusvirus replicase. We demonstrate that TBSV RNA replication and the mono- and bi-ubiquitination level of p33 is decreased in rad6Δ yeast. However, plasmid-based expression of AtUbc2p could complement both defects in rad6Δ yeast. Knockdown of UBC2 expression in plants also decreases tombusvirus accumulation and reduces symptom severity, suggesting that Ubc2p is critical for virus replication in plants. We provide evidence that Rad6p is involved in promoting the subversion of Vps23p and Vps4p ESCRT proteins for viral replicase complex assembly. - Highlights: • Tombusvirus p33 replication protein interacts with cellular RAD6/Ubc2 E2 Enzymes. • Deletion of RAD6 reduces tombusvirus replication in yeast. • Silencing of UBC2 in plants inhibits tombusvirus replication. • Mono- and bi-ubiquitination of p33 replication protein in yeast and in vitro. • Rad6p promotes the recruitment ofmore » cellular ESCRT proteins into the tombusvirus replicase.« less

  • Cellular Ubc2/Rad6 E2 Ubiquitin-Conjugating Enzyme facilitates tombusvirus replication in yeast and plants.
    Virology, 2015
    Co-Authors: Yoshiyuki Imura, Melissa Molho, Chingkai Chuang, Peter D Nagy
    Abstract:

    Mono- and multi-ubiquitination alters the functions and subcellular localization of many cellular and viral proteins. Viruses can co-opt or actively manipulate the ubiquitin network to support viral processes or suppress innate immunity. Using yeast (Saccharomyces cerevisiae) model host, we show that the yeast Rad6p (radiation sensitive 6) E2 Ubiquitin-Conjugating Enzyme and its plant ortholog, AtUbc2, interact with two tombusviral replication proteins and these E2 Ubiquitin-Conjugating Enzymes could be co-purified with the tombusvirus replicase. We demonstrate that TBSV RNA replication and the mono- and bi-ubiquitination level of p33 is decreased in rad6Δ yeast. However, plasmid-based expression of AtUbc2p could complement both defects in rad6Δ yeast. Knockdown of UBC2 expression in plants also decreases tombusvirus accumulation and reduces symptom severity, suggesting that Ubc2p is critical for virus replication in plants. We provide evidence that Rad6p is involved in promoting the subversion of Vps23p and Vps4p ESCRT proteins for viral replicase complex assembly. - Highlights: • Tombusvirus p33 replication protein interacts with cellular RAD6/Ubc2 E2 Enzymes. • Deletion of RAD6 reduces tombusvirus replication in yeast. • Silencing of UBC2 in plants inhibits tombusvirus replication. • Mono- and bi-ubiquitination of p33 replication protein in yeast and in vitro. • Rad6p promotes the recruitment ofmore » cellular ESCRT proteins into the tombusvirus replicase.« less

  • Cellular Ubc2/Rad6 E2 Ubiquitin-Conjugating Enzyme facilitates tombusvirus replication in yeast and plants.
    Virology, 2015
    Co-Authors: Yoshiyuki Imura, Melissa Molho, Chingkai Chuang, Peter D Nagy
    Abstract:

    Mono- and multi-ubiquitination alters the functions and subcellular localization of many cellular and viral proteins. Viruses can co-opt or actively manipulate the ubiquitin network to support viral processes or suppress innate immunity. Using yeast (Saccharomyces cerevisiae) model host, we show that the yeast Rad6p (radiation sensitive 6) E2 Ubiquitin-Conjugating Enzyme and its plant ortholog, AtUbc2, interact with two tombusviral replication proteins and these E2 Ubiquitin-Conjugating Enzymes could be co-purified with the tombusvirus replicase. We demonstrate that TBSV RNA replication and the mono- and bi-ubiquitination level of p33 is decreased in rad6Δ yeast. However, plasmid-based expression of AtUbc2p could complement both defects in rad6Δ yeast. Knockdown of UBC2 expression in plants also decreases tombusvirus accumulation and reduces symptom severity, suggesting that Ubc2p is critical for virus replication in plants. We provide evidence that Rad6p is involved in promoting the subversion of Vps23p and Vps4p ESCRT proteins for viral replicase complex assembly.

  • cdc34p ubiquitin conjugating Enzyme is a component of the tombusvirus replicase complex and ubiquitinates p33 replication protein
    Journal of Virology, 2008
    Co-Authors: Daniel Barajas, Tadas Panavas, David A Herbst, Peter D Nagy
    Abstract:

    To identify host proteins interacting with Tomato bushy stunt virus (TBSV) replication proteins in a genome-wide scale, we have used a yeast (Saccharomyces cerevisiae) proteome microarray carrying 4,088 purified proteins. This approach led to the identification of 58 yeast proteins that interacted with p33 replication protein. The identified host proteins included protein chaperones, ubiquitin-associated proteins, translation factors, RNA-modifying Enzymes, and other proteins with yet-unknown functions. We confirmed that 19 of the identified host proteins bound to p33 in vitro or in a split-ubiquitin-based two-hybrid assay. Further analysis of Cdc34p E2 Ubiquitin-Conjugating Enzyme, which is one of the host proteins interacting with p33, revealed that Cdc34p is a novel component of the purified viral replicase. Downregulation of Cdc34p expression in yeast, which supports replication of a TBSV replicon RNA (repRNA), reduced repRNA accumulation and the activity of the tombusvirus replicase by up to fivefold. Overexpression of wild-type Cdc34p, but not that of an E2-defective mutant of Cdc34p, increased repRNA accumulation, suggesting a significant role for the Ubiquitin-Conjugating Enzyme function of Cdc34p in TBSV replication. Also, Cdc34p was able to ubiquitinate p33 in vitro. In addition, we have shown that p33 becomes ubiquitinated in vivo. We propose that ubiquitination of p33 likely alters its function or affects the recruitment of host factors during TBSV replication.

Yoshiyuki Imura - One of the best experts on this subject based on the ideXlab platform.

  • cellular ubc2 rad6 e2 ubiquitin conjugating Enzyme facilitates tombusvirus replication in yeast and plants
    Virology, 2015
    Co-Authors: Yoshiyuki Imura, Melissa Molho, Chingkai Chuang, Peter D Nagy
    Abstract:

    Mono- and multi-ubiquitination alters the functions and subcellular localization of many cellular and viral proteins. Viruses can co-opt or actively manipulate the ubiquitin network to support viral processes or suppress innate immunity. Using yeast (Saccharomyces cerevisiae) model host, we show that the yeast Rad6p (radiation sensitive 6) E2 Ubiquitin-Conjugating Enzyme and its plant ortholog, AtUbc2, interact with two tombusviral replication proteins and these E2 Ubiquitin-Conjugating Enzymes could be co-purified with the tombusvirus replicase. We demonstrate that TBSV RNA replication and the mono- and bi-ubiquitination level of p33 is decreased in rad6Δ yeast. However, plasmid-based expression of AtUbc2p could complement both defects in rad6Δ yeast. Knockdown of UBC2 expression in plants also decreases tombusvirus accumulation and reduces symptom severity, suggesting that Ubc2p is critical for virus replication in plants. We provide evidence that Rad6p is involved in promoting the subversion of Vps23p and Vps4p ESCRT proteins for viral replicase complex assembly. - Highlights: • Tombusvirus p33 replication protein interacts with cellular RAD6/Ubc2 E2 Enzymes. • Deletion of RAD6 reduces tombusvirus replication in yeast. • Silencing of UBC2 in plants inhibits tombusvirus replication. • Mono- and bi-ubiquitination of p33 replication protein in yeast and in vitro. • Rad6p promotes the recruitment ofmore » cellular ESCRT proteins into the tombusvirus replicase.« less

  • Cellular Ubc2/Rad6 E2 Ubiquitin-Conjugating Enzyme facilitates tombusvirus replication in yeast and plants.
    Virology, 2015
    Co-Authors: Yoshiyuki Imura, Melissa Molho, Chingkai Chuang, Peter D Nagy
    Abstract:

    Mono- and multi-ubiquitination alters the functions and subcellular localization of many cellular and viral proteins. Viruses can co-opt or actively manipulate the ubiquitin network to support viral processes or suppress innate immunity. Using yeast (Saccharomyces cerevisiae) model host, we show that the yeast Rad6p (radiation sensitive 6) E2 Ubiquitin-Conjugating Enzyme and its plant ortholog, AtUbc2, interact with two tombusviral replication proteins and these E2 Ubiquitin-Conjugating Enzymes could be co-purified with the tombusvirus replicase. We demonstrate that TBSV RNA replication and the mono- and bi-ubiquitination level of p33 is decreased in rad6Δ yeast. However, plasmid-based expression of AtUbc2p could complement both defects in rad6Δ yeast. Knockdown of UBC2 expression in plants also decreases tombusvirus accumulation and reduces symptom severity, suggesting that Ubc2p is critical for virus replication in plants. We provide evidence that Rad6p is involved in promoting the subversion of Vps23p and Vps4p ESCRT proteins for viral replicase complex assembly. - Highlights: • Tombusvirus p33 replication protein interacts with cellular RAD6/Ubc2 E2 Enzymes. • Deletion of RAD6 reduces tombusvirus replication in yeast. • Silencing of UBC2 in plants inhibits tombusvirus replication. • Mono- and bi-ubiquitination of p33 replication protein in yeast and in vitro. • Rad6p promotes the recruitment ofmore » cellular ESCRT proteins into the tombusvirus replicase.« less

  • Cellular Ubc2/Rad6 E2 Ubiquitin-Conjugating Enzyme facilitates tombusvirus replication in yeast and plants.
    Virology, 2015
    Co-Authors: Yoshiyuki Imura, Melissa Molho, Chingkai Chuang, Peter D Nagy
    Abstract:

    Mono- and multi-ubiquitination alters the functions and subcellular localization of many cellular and viral proteins. Viruses can co-opt or actively manipulate the ubiquitin network to support viral processes or suppress innate immunity. Using yeast (Saccharomyces cerevisiae) model host, we show that the yeast Rad6p (radiation sensitive 6) E2 Ubiquitin-Conjugating Enzyme and its plant ortholog, AtUbc2, interact with two tombusviral replication proteins and these E2 Ubiquitin-Conjugating Enzymes could be co-purified with the tombusvirus replicase. We demonstrate that TBSV RNA replication and the mono- and bi-ubiquitination level of p33 is decreased in rad6Δ yeast. However, plasmid-based expression of AtUbc2p could complement both defects in rad6Δ yeast. Knockdown of UBC2 expression in plants also decreases tombusvirus accumulation and reduces symptom severity, suggesting that Ubc2p is critical for virus replication in plants. We provide evidence that Rad6p is involved in promoting the subversion of Vps23p and Vps4p ESCRT proteins for viral replicase complex assembly.

Scott M. Plafker - One of the best experts on this subject based on the ideXlab platform.

  • Loss of the ubiquitin conjugating Enzyme UBE2E3 induces cellular senescence.
    Redox biology, 2018
    Co-Authors: Kendra S. Plafker, Katarzyna Zyla, William L. Berry, Scott M. Plafker
    Abstract:

    Cellular senescence plays essential roles in tissue homeostasis as well as a host of diseases ranging from cancers to age-related neurodegeneration. Various molecular pathways can induce senescence and these different pathways dictate the phenotypic and metabolic changes that accompany the transition to, and maintenance of, the senescence state. Here, we describe a novel senescence phenotype induced by depletion of UBE2E3, a highly-conserved, metazoan ubiquitin conjugating Enzyme. Cells depleted of UBE2E3 become senescent in the absence of overt DNA damage and have a distinct senescence-associated secretory phenotype, increased mitochondrial and lysosomal mass, an increased sensitivity to mitochondrial and lysosomal poisons, and an increased basal autophagic flux. This senescence phenotype can be partially suppressed by co-depletion of either p53 or its cognate target gene, p21CIP1/WAF1, or by co-depleting the tumor suppressor p16INK4a. Together, these data describe a direct link of a ubiquitin conjugating Enzyme to cellular senescence and further underscore the consequences of disrupting the integration between the ubiquitin proteolysis system and the autophagy machinery.

  • The Human Ubiquitin Conjugating Enzyme, UBE2E3, Is Required for Proliferation of Retinal Pigment Epithelial Cells
    Investigative ophthalmology & visual science, 2008
    Co-Authors: Kendra S. Plafker, Krysten M. Farjo, Allan F. Wiechmann, Scott M. Plafker
    Abstract:

    Purpose Cell cycle progression is governed by the coordinated activities of kinases, phosphatases, and the ubiquitin system. The entire complement of ubiquitin pathway components that mediate this process in retinal pigment epithelial (RPE) cells remains to be identified. This study was undertaken to determine whether the human Ubiquitin-Conjugating Enzyme, UBE2E3, is essential for RPE cell proliferation.

  • Importin-11, a nuclear import receptor for the Ubiquitin-Conjugating Enzyme, UbcM2
    The EMBO journal, 2000
    Co-Authors: Scott M. Plafker, Ian G. Macara
    Abstract:

    Importins are members of a family of transport receptors (karyopherins) that mediate the nucleocytoplasmic transport of protein and RNA cargoes. We identified importin-11 as a potential new human member of this family, on the basis of limited similarity to the Saccharomyces cerevisiae protein, Lph2p, and cloned the complete open reading frame. Importin-11 interacts with the Ran GTPase, and constitutively shuttles between the nuclear and cytoplasmic compartments. A yeast dihybrid screen identified UbcM2, an E2-type Ubiquitin-Conjugating Enzyme, as a binding partner and potential transport cargo for importin-11. Importin-11 and UbcM2 interact directly, and the complex is disassembled by Ran:GTP but not by Ran:GDP. UbcM2 is constitutively nuclear and shuttles between the nuclear and cytoplasmic compartments. Nuclear import of UbcM2 requires Ran and importin-11, and is inhibited by wheatgerm agglutinin, energy depletion or dominant interfering mutants of Ran and importin-beta. These data establish importin-11 as a new member of the karyopherin family of transport receptors, and identify UbcM2 as a nuclear member of the E2 Ubiquitin-Conjugating Enzyme family.

Chingkai Chuang - One of the best experts on this subject based on the ideXlab platform.

  • cellular ubc2 rad6 e2 ubiquitin conjugating Enzyme facilitates tombusvirus replication in yeast and plants
    Virology, 2015
    Co-Authors: Yoshiyuki Imura, Melissa Molho, Chingkai Chuang, Peter D Nagy
    Abstract:

    Mono- and multi-ubiquitination alters the functions and subcellular localization of many cellular and viral proteins. Viruses can co-opt or actively manipulate the ubiquitin network to support viral processes or suppress innate immunity. Using yeast (Saccharomyces cerevisiae) model host, we show that the yeast Rad6p (radiation sensitive 6) E2 Ubiquitin-Conjugating Enzyme and its plant ortholog, AtUbc2, interact with two tombusviral replication proteins and these E2 Ubiquitin-Conjugating Enzymes could be co-purified with the tombusvirus replicase. We demonstrate that TBSV RNA replication and the mono- and bi-ubiquitination level of p33 is decreased in rad6Δ yeast. However, plasmid-based expression of AtUbc2p could complement both defects in rad6Δ yeast. Knockdown of UBC2 expression in plants also decreases tombusvirus accumulation and reduces symptom severity, suggesting that Ubc2p is critical for virus replication in plants. We provide evidence that Rad6p is involved in promoting the subversion of Vps23p and Vps4p ESCRT proteins for viral replicase complex assembly. - Highlights: • Tombusvirus p33 replication protein interacts with cellular RAD6/Ubc2 E2 Enzymes. • Deletion of RAD6 reduces tombusvirus replication in yeast. • Silencing of UBC2 in plants inhibits tombusvirus replication. • Mono- and bi-ubiquitination of p33 replication protein in yeast and in vitro. • Rad6p promotes the recruitment ofmore » cellular ESCRT proteins into the tombusvirus replicase.« less

  • Cellular Ubc2/Rad6 E2 Ubiquitin-Conjugating Enzyme facilitates tombusvirus replication in yeast and plants.
    Virology, 2015
    Co-Authors: Yoshiyuki Imura, Melissa Molho, Chingkai Chuang, Peter D Nagy
    Abstract:

    Mono- and multi-ubiquitination alters the functions and subcellular localization of many cellular and viral proteins. Viruses can co-opt or actively manipulate the ubiquitin network to support viral processes or suppress innate immunity. Using yeast (Saccharomyces cerevisiae) model host, we show that the yeast Rad6p (radiation sensitive 6) E2 Ubiquitin-Conjugating Enzyme and its plant ortholog, AtUbc2, interact with two tombusviral replication proteins and these E2 Ubiquitin-Conjugating Enzymes could be co-purified with the tombusvirus replicase. We demonstrate that TBSV RNA replication and the mono- and bi-ubiquitination level of p33 is decreased in rad6Δ yeast. However, plasmid-based expression of AtUbc2p could complement both defects in rad6Δ yeast. Knockdown of UBC2 expression in plants also decreases tombusvirus accumulation and reduces symptom severity, suggesting that Ubc2p is critical for virus replication in plants. We provide evidence that Rad6p is involved in promoting the subversion of Vps23p and Vps4p ESCRT proteins for viral replicase complex assembly. - Highlights: • Tombusvirus p33 replication protein interacts with cellular RAD6/Ubc2 E2 Enzymes. • Deletion of RAD6 reduces tombusvirus replication in yeast. • Silencing of UBC2 in plants inhibits tombusvirus replication. • Mono- and bi-ubiquitination of p33 replication protein in yeast and in vitro. • Rad6p promotes the recruitment ofmore » cellular ESCRT proteins into the tombusvirus replicase.« less

  • Cellular Ubc2/Rad6 E2 Ubiquitin-Conjugating Enzyme facilitates tombusvirus replication in yeast and plants.
    Virology, 2015
    Co-Authors: Yoshiyuki Imura, Melissa Molho, Chingkai Chuang, Peter D Nagy
    Abstract:

    Mono- and multi-ubiquitination alters the functions and subcellular localization of many cellular and viral proteins. Viruses can co-opt or actively manipulate the ubiquitin network to support viral processes or suppress innate immunity. Using yeast (Saccharomyces cerevisiae) model host, we show that the yeast Rad6p (radiation sensitive 6) E2 Ubiquitin-Conjugating Enzyme and its plant ortholog, AtUbc2, interact with two tombusviral replication proteins and these E2 Ubiquitin-Conjugating Enzymes could be co-purified with the tombusvirus replicase. We demonstrate that TBSV RNA replication and the mono- and bi-ubiquitination level of p33 is decreased in rad6Δ yeast. However, plasmid-based expression of AtUbc2p could complement both defects in rad6Δ yeast. Knockdown of UBC2 expression in plants also decreases tombusvirus accumulation and reduces symptom severity, suggesting that Ubc2p is critical for virus replication in plants. We provide evidence that Rad6p is involved in promoting the subversion of Vps23p and Vps4p ESCRT proteins for viral replicase complex assembly.

Melissa Molho - One of the best experts on this subject based on the ideXlab platform.

  • cellular ubc2 rad6 e2 ubiquitin conjugating Enzyme facilitates tombusvirus replication in yeast and plants
    Virology, 2015
    Co-Authors: Yoshiyuki Imura, Melissa Molho, Chingkai Chuang, Peter D Nagy
    Abstract:

    Mono- and multi-ubiquitination alters the functions and subcellular localization of many cellular and viral proteins. Viruses can co-opt or actively manipulate the ubiquitin network to support viral processes or suppress innate immunity. Using yeast (Saccharomyces cerevisiae) model host, we show that the yeast Rad6p (radiation sensitive 6) E2 Ubiquitin-Conjugating Enzyme and its plant ortholog, AtUbc2, interact with two tombusviral replication proteins and these E2 Ubiquitin-Conjugating Enzymes could be co-purified with the tombusvirus replicase. We demonstrate that TBSV RNA replication and the mono- and bi-ubiquitination level of p33 is decreased in rad6Δ yeast. However, plasmid-based expression of AtUbc2p could complement both defects in rad6Δ yeast. Knockdown of UBC2 expression in plants also decreases tombusvirus accumulation and reduces symptom severity, suggesting that Ubc2p is critical for virus replication in plants. We provide evidence that Rad6p is involved in promoting the subversion of Vps23p and Vps4p ESCRT proteins for viral replicase complex assembly. - Highlights: • Tombusvirus p33 replication protein interacts with cellular RAD6/Ubc2 E2 Enzymes. • Deletion of RAD6 reduces tombusvirus replication in yeast. • Silencing of UBC2 in plants inhibits tombusvirus replication. • Mono- and bi-ubiquitination of p33 replication protein in yeast and in vitro. • Rad6p promotes the recruitment ofmore » cellular ESCRT proteins into the tombusvirus replicase.« less

  • Cellular Ubc2/Rad6 E2 Ubiquitin-Conjugating Enzyme facilitates tombusvirus replication in yeast and plants.
    Virology, 2015
    Co-Authors: Yoshiyuki Imura, Melissa Molho, Chingkai Chuang, Peter D Nagy
    Abstract:

    Mono- and multi-ubiquitination alters the functions and subcellular localization of many cellular and viral proteins. Viruses can co-opt or actively manipulate the ubiquitin network to support viral processes or suppress innate immunity. Using yeast (Saccharomyces cerevisiae) model host, we show that the yeast Rad6p (radiation sensitive 6) E2 Ubiquitin-Conjugating Enzyme and its plant ortholog, AtUbc2, interact with two tombusviral replication proteins and these E2 Ubiquitin-Conjugating Enzymes could be co-purified with the tombusvirus replicase. We demonstrate that TBSV RNA replication and the mono- and bi-ubiquitination level of p33 is decreased in rad6Δ yeast. However, plasmid-based expression of AtUbc2p could complement both defects in rad6Δ yeast. Knockdown of UBC2 expression in plants also decreases tombusvirus accumulation and reduces symptom severity, suggesting that Ubc2p is critical for virus replication in plants. We provide evidence that Rad6p is involved in promoting the subversion of Vps23p and Vps4p ESCRT proteins for viral replicase complex assembly. - Highlights: • Tombusvirus p33 replication protein interacts with cellular RAD6/Ubc2 E2 Enzymes. • Deletion of RAD6 reduces tombusvirus replication in yeast. • Silencing of UBC2 in plants inhibits tombusvirus replication. • Mono- and bi-ubiquitination of p33 replication protein in yeast and in vitro. • Rad6p promotes the recruitment ofmore » cellular ESCRT proteins into the tombusvirus replicase.« less

  • Cellular Ubc2/Rad6 E2 Ubiquitin-Conjugating Enzyme facilitates tombusvirus replication in yeast and plants.
    Virology, 2015
    Co-Authors: Yoshiyuki Imura, Melissa Molho, Chingkai Chuang, Peter D Nagy
    Abstract:

    Mono- and multi-ubiquitination alters the functions and subcellular localization of many cellular and viral proteins. Viruses can co-opt or actively manipulate the ubiquitin network to support viral processes or suppress innate immunity. Using yeast (Saccharomyces cerevisiae) model host, we show that the yeast Rad6p (radiation sensitive 6) E2 Ubiquitin-Conjugating Enzyme and its plant ortholog, AtUbc2, interact with two tombusviral replication proteins and these E2 Ubiquitin-Conjugating Enzymes could be co-purified with the tombusvirus replicase. We demonstrate that TBSV RNA replication and the mono- and bi-ubiquitination level of p33 is decreased in rad6Δ yeast. However, plasmid-based expression of AtUbc2p could complement both defects in rad6Δ yeast. Knockdown of UBC2 expression in plants also decreases tombusvirus accumulation and reduces symptom severity, suggesting that Ubc2p is critical for virus replication in plants. We provide evidence that Rad6p is involved in promoting the subversion of Vps23p and Vps4p ESCRT proteins for viral replicase complex assembly.