This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Google Scholar
Right arrow Articles by Kim, E. T.
Right arrow Articles by Ahn, J.-H.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Kim, E. T.
Right arrow Articles by Ahn, J.-H.

 Previous Article  |  Next Article 

Journal of Virology, December 2009, p. 12046-12056, Vol. 83, No. 23
0022-538X/09/$08.00+0     doi:10.1128/JVI.00411-09
Copyright © 2009, American Society for Microbiology. All Rights Reserved.

Cleavage Specificity of the UL48 Deubiquitinating Protease Activity of Human Cytomegalovirus and the Growth of an Active-Site Mutant Virus in Cultured Cells {triangledown}

Eui Tae Kim,1,{dagger} Se Eun Oh,1,{dagger} Yun-Ok Lee,1,{dagger} Wade Gibson,2 and Jin-Hyun Ahn1*

Department of Molecular Cell Biology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Suwon 440-746, Republic of Korea,1 Department of Pharmacology and Molecular Sciences, the Johns Hopkins University School of Medicine, Baltimore, Maryland 212052

Received 25 February 2009/ Accepted 11 September 2009

The human cytomegalovirus (HCMV) open reading frame UL48 encodes a 253-kDa tegument protein that is closely associated with the capsid and was recently shown to have ubiquitin-specific protease activity (J. Wang, A. N. Loveland, L. M. Kattenhorn, H. L. Ploegh, and W. Gibson, J. Virol. 80:6003-6012, 2006). Here, we examined the cleavage specificity of this deubiquitinase (DUB) and replication characteristics of an active-site mutant virus. The purified catalytic domain of the UL48 DUB (1 to 359 amino acids), corresponding to the herpes simplex virus UL36USP DUB (L. M. Kattenhorn, G. A. Korbel, B. M. Kessler, E. Spooner, and H. L. Ploegh, Mol. Cell 19:547-557, 2005), efficiently released ubiquitin but not ubiquitin-like modifications from a hemagglutinin peptide substrate. Mutating the active-site residues Cys24 or His162 (C24S and H162A, respectively) abolished this activity. The HCMV UL48 and HSV UL36USP DUBs cleaved both Lys48- and Lys63-linked ubiquitin dimers and oligomers, showing more activity toward Lys63 linkages. The DUB activity of the full-length UL48 protein immunoprecipitated from virus-infected cells also showed a better cleavage of Lys63-linked ubiquitinated substrates. An HCMV (Towne) mutant virus in which the UL48 DUB activity was destroyed [UL48(C24S)] produced 10-fold less progeny virus and reduced amounts of viral proteins compared to wild-type virus at a low multiplicity of infection. The mutant virus also produced perceptibly less overall deubiquitination than the wild-type virus. Our findings demonstrate that the HCMV UL48 DUB contains both a ubiquitin-specific carboxy-terminal hydrolase activity and an isopeptidase activity that favors ubiquitin Lys63 linkages and that these activities can influence virus replication in cultured cells.

* Corresponding author. Mailing address: Department of Molecular Cell Biology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, 300 Cheoncheondong, Jangangu, Suwon, Gyeonggido 440-746, Republic of Korea. Phone: 82-31-299-6222. Fax: 82-31-299-6435. E-mail: jahn{at}med.skku.ac.kr

{triangledown} Published ahead of print on 16 September 2009.

{dagger} E.T.K., S.E.O., and Y.-O.L. contributed equally to this paper.

Journal of Virology, December 2009, p. 12046-12056, Vol. 83, No. 23
0022-538X/09/$08.00+0     doi:10.1128/JVI.00411-09
Copyright © 2009, American Society for Microbiology. All Rights Reserved.





Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»