Dataset Information

Cowpox virus proteomics reveals massive ubiquitination and proteasomal degradation of viral proteins but stable virus cores

ABSTRACT: The ubiquitin-proteasome system (UPS) is essential for replication of Orthopoxviruses (OPV) like vaccinia and cowpox virus (CPXV). Although several proteome studies identified ubiquitin as part of OPV particles, distinct modification sites are largely unknown. Moreover, the UPS plays a key role in poxvirus core uncoating but the underlying mechanisms are still elusive. In the presented study we show that impairment of CPXV replication by proteasome inhibition is caused by a lack of uncoating which can be observed by electron microscopy. These results suggest, that UPS-dependent degradation of viral core proteins is the mechanism underlying CPXV genome uncoating. To proof this hypothesis we analyzed the mature virion ubiquitinome of CPXV using mass spectrometry (MS). We elucidated 137 conserved ubiquitination sites in 54 viral proteins among five CPXV strains verifying ubiquitin is a major poxvirus modification. Structural core proteins were massively ubiquitinated and virions contained large amounts of K48-linked polyubiquitin supporting the hypothesis. Hence, we aimed to show the proteasome-dependent degradation of CPXV core proteins in infected HeLa cells. However, using MS-based quantitative analysis of ubiquitinated virus proteins early in infection we were not able to show the degradation of viral core proteins. Instead, our results revealed the proteasomal degradation of viral proteins associated with the formation of prereplication sites early in infection.

INSTRUMENT(S): LTQ Orbitrap

ORGANISM(S): Cowpox Virus Cowpox Virus (cpv)

TISSUE(S): Permanent Cell Line Cell

SUBMITTER: Marica Grossegesse

LAB HEAD: Andreas Nitsche

PROVIDER: PXD006426 | Pride | 2018-02-07

REPOSITORIES: Pride

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Global ubiquitination analysis reveals extensive modification and proteasomal degradation of cowpox virus proteins, but preservation of viral cores.

Grossegesse Marica M Doellinger Joerg J Fritsch Annemarie A Laue Michael M Piesker Janett J Schaade Lars L Nitsche Andreas A

Scientific reports 20180129 1

The emergence of Variola virus-like viruses by natural evolution of zoonotic Orthopoxviruses, like Cowpox virus (CPXV), is a global health threat. The proteasome is essential for poxvirus replication, making the viral components interacting with the ubiquitin-proteasome system attractive antiviral targets. We show that proteasome inhibition impairs CPXV replication by prevention of uncoating, suggesting that uncoating is mediated by proteasomal degradation of viral core proteins. Although Orthop ...[more]

PMID: 29379051

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Dataset Information

Cowpox virus proteomics reveals massive ubiquitination and proteasomal degradation of viral proteins but stable virus cores

Publications

Global ubiquitination analysis reveals extensive modification and proteasomal degradation of cowpox virus proteins, but preservation of viral cores.

Similar Datasets

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