Proteasome-dependent, ubiquitin-independent degradation of Daxx by the viral pp71 protein in human cytomegalovirus-infected cells.
The cellular Daxx protein represses human cytomegalovirus (HCMV) gene expression from the major immediate early promoter. HCMV prevents Daxx-mediated silencing during lytic infection by delivering the viral pp71 tegument protein to the nucleus, where pp71 binds to and induces the proteasomal degradation of Daxx. In this study, we show that a functional ubiquitin pathway is not required for the proteasomal degradation of the endogenous Daxx protein by tegument-delivered pp71 in HCMV-infected cells, demonstrating that the pp71-mediated degradation of Daxx occurs through a proteasome-dependent, ubiquitin-independent pathway.
Hwang
Jiwon
J
Institute for Molecular Virology and McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, WI 53706, USA.
Kalejta
Robert F
RF
D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism*; D000818:Animals; D002460:Cell Line; D056970:Co-Repressor Proteins; D003587:Cytomegalovirus / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology; D003586:Cytomegalovirus Infections / Q000276:immunology; D015967:Gene Expression Regulation, Viral; D006801:Humans; D051379:Mice; D018832:Molecular Chaperones; D009687:Nuclear Proteins / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D014158:Transcription, Genetic; D025801:Ubiquitin / Q000378:metabolism*; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*
D048868:Adaptor Proteins, Signal Transducing; D056970:Co-Repressor Proteins; C106985:DAXX protein, human; D018832:Molecular Chaperones; D009687:Nuclear Proteins; D025801:Ubiquitin; D014764:Viral Proteins; C051298:cytomegalovirus phosphoprotein 71kDa; D046988:Proteasome Endopeptidase Complex