Journal article
Cell Surface Expression and Fusion by the Varicella-Zoster Virus gH:gL Glycoprotein Complex: Analysis by Laser Scanning Confocal Microscopy
Virology (New York, N.Y.), Vol.210(2), pp.429-440
07/10/1995
DOI: 10.1006/viro.1995.1359
PMID: 7618278
Abstract
Varicella-zoster virus (VZV) open reading frames 37 and 60 encode the glycoproteins gH (gpIII) and gL (gpVI), respectively. The property of gH:gL complex formation is highly conserved among the herpesviruses, even though the VZV gL component diverges greatly from other herpesvirus gL homologs. VZV gL by itself was processed to a mature product within the Golgi. To evaluate the structure:function relationships for VZV gH:gL complex formation, the VZV gL product was modified by site-directed mutagenesis of three cysteine residues. When the transfection products were examined by laser scanning confocal microscopy, expression of the wild-type gH:gL complex was clearly visualized by a uniform distribution of gH molecules across the cell surface. In contrast, transfection with wild-type gH:mutant gL led to a marked change in the trafficking pattern; gH was not processed in the Golgi and not detected at the cell surface. Likewise, replacement of the gL cysteina residues interfered with the fusogenic properties of the gH:gL complex. Whereas coexpression of wild-type VZV gH:gL caused extensive cell-to-cell fusion with polykaryocytosis, no cell fusion occurred following transfection with gH:mutant gL. Whether another VZV glycoprotein could substitute for VZV gL was investigated within the same transfection system, with the discovery that either V-ZV gE (gpI) or VZV gL (gpIV) facilitated the cell surface expression of VZV gH. The gH:gE or gH:gL interaction led to a capping or patching phenomenon never seen on the surface of a cell expressing gH:gL complexes; furthermore, cell-to-cell fusion was not observed. The fact that VZV gL, unlike other herpesviral glycoproteins, lacked a traditional signal sequence was investigated further by computer-assisted BlockSearch sequence analysis. The BlockSearch program assigned VZV gL to a family of proteins which lack a typical endoplasmic reticulum signal sequence but possess instead an endoplasmic reticulum targeting sequence. Since the latter sequence is common to many chaperone proteins, VZV gL most likely behaves in a similar manner.
Details
- Title: Subtitle
- Cell Surface Expression and Fusion by the Varicella-Zoster Virus gH:gL Glycoprotein Complex: Analysis by Laser Scanning Confocal Microscopy
- Creators
- Karen M DuusChristopher HatfieldCharles Grose
- Resource Type
- Journal article
- Publication Details
- Virology (New York, N.Y.), Vol.210(2), pp.429-440
- DOI
- 10.1006/viro.1995.1359
- PMID
- 7618278
- NLM abbreviation
- Virology
- ISSN
- 0042-6822
- eISSN
- 1096-0341
- Publisher
- Elsevier Inc
- Language
- English
- Date published
- 07/10/1995
- Academic Unit
- Stead Family Department of Pediatrics; Infectious Disease (Pediatrics)
- Record Identifier
- 9984093507502771
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