JVI Figure table search 04
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
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
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Zhou, G.
Right arrow Articles by Roizman, B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Zhou, G.
Right arrow Articles by Roizman, B.

 Previous Article  |  Next Article 

Journal of Virology, March 2003, p. 3759-3767, Vol. 77, No. 6
0022-538X/03/$08.00+0     DOI: 10.1128/JVI.77.6.3759-3767.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.

The Domains of Glycoprotein D Required To Block Apoptosis Induced by Herpes Simplex Virus 1 Are Largely Distinct from Those Involved in Cell-Cell Fusion and Binding to Nectin1

Guoying Zhou,1 Elisa Avitabile,2 Gabriella Campadelli-Fiume,2 and Bernard Roizman1*

Marjorie B. Kovler Viral Oncology Laboratories, University of Chicago, Chicago, Illinois,1 Section on Microbiology and Virology, Department of Experimental Pathology, University of Bologna, Bologna, Italy2

Received 29 October 2002/ Accepted 23 December 2002

Glycoprotein D (gD) interacts with two alternative protein receptors, nectin1 and HveA, to mediate herpes simplex virus (HSV) entry into cells. Fusion of the envelope with the plasma membrane requires, in addition to gD, glycoproteins gB, gH, and gL. Coexpression of the four glycoproteins (gD, gB, gH, and gL) promotes cell-cell fusion. gD delivered in trans is also capable of blocking the apoptosis induced by gD deletion viruses grown either in noncomplementing cells (gD-/-) or in complementing cells (gD-/+). While ectopic expression of cation-independent mannose-6 phosphate receptor blocks apoptosis induced by both stocks, other requirements differ. Thus, apoptosis induced by gD-/- virus is blocked by full-length gD (or two gD fragments reconstituting a full-length molecule), whereas ectopic expression of the gD ectodomain is sufficient to block apoptosis induced by gD-/+ virus. In this report we took advantage of a set of gD insertion-deletion mutants to map the domains of gD required to block apoptosis by gD-/- and gD-/+ viruses and those involved in cell-cell fusion. The mutations that resulted in failure to block apoptosis were the same for gD-/- and gD-/+ viruses and were located in three sites, one within the immunoglobulin-type core region (residues 125, 126, and 151), one in the upstream connector region (residues 34 and 43), and one in the C-terminal portion of the ectodomain (residue 277). A mutant that carried amino acid substitutions at the three glycosylation sites failed to block apoptosis but behaved like wild-type gD in all other assays. The mutations that inhibited polykaryocyte formation were located in the upstream connector region (residues 34 and 43), at the {alpha}1 helix (residue 77), in the immunoglobulin core and downstream regions (residue 151 and 187), and at the {alpha}3 helix (residues 243 and 246). Binding of soluble nectin1-Fc to cells expressing the mutant gDs was generally affected by the same mutations that affected fusion, with one notable exception ({Delta}277-310), which affected fusion without hampering nectin1 binding. This deletion likely identifies a region of gD involved in fusion activity at a post-nectin1-binding step. We conclude that whereas mutations that affected all functions (e.g., upstream connector region and residue 151) may be detrimental to overall gD structure, the mutations that affect specific activities identify domains of gD involved in the interactions with entry receptors and fusogenic glycoproteins and with cellular proteins required to block apoptosis. The evidence that glycosylation of gD is required for blocking apoptosis supports the conclusion that the interacting protein is the mannose-6 phosphate receptor.


* Corresponding author. Mailing address: The Marjorie B. Kovler Viral Oncology Laboratories, The University of Chicago, 910 E. 58th St., Chicago, IL 60637. Phone: (773) 702-1898. Fax: (773) 702-1631. E-mail: bernard{at}cummings.uchicago.edu.


Journal of Virology, March 2003, p. 3759-3767, Vol. 77, No. 6
0022-538X/03/$08.00+0     DOI: 10.1128/JVI.77.6.3759-3767.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.




This article has been cited by other articles:




Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. Mol. Cell. Biol. Microbiol. Mol. Biol. Rev.
Clin. Vaccine Immunol. ALL ASM JOURNALS

Copyright © 2003 by the American Society for Microbiology. All rights reserved.