Phosphorylation of Human Cytomegalovirus Glycoprotein B (gB) at the Acidic Cluster Casein Kinase 2 Site (Ser900) Is Required for Localization of gB to the trans-Golgi Network and Efficient Virus Replication

Michael A. Jarvis, Thomas R. Jones, Derek D. Drummond, Patsy P. Smith, William J. Britt, Jay Nelson, Carl J. Baldick

Research output: Contribution to journalArticle

24 Citations (Scopus)

Abstract

Human cytomegalovirus (HCMV) glycoprotein B (gB), encoded by the UL55 open reading frame, is an essential envelope glycoprotein involved in cell attachment and entry. Previously, we identified residue serine 900 (Ser 900) as a unique site of reversible casein kinase 2 phosphorylation in the cytoplasmic domain of HCMV gB. We have also recently shown that gB is localized to the trans-Golgi network (TGN) in HCMV-permissive cells, thereby identifying the TGN as a possible site of virus envelopment. The aim of the current study was to determine the role of Ser900 phosphorylation in transport of gB to the TGN and in HCMV biogenesis. Recombinant HCMV strains were constructed that expressed gB molecules containing either an aspartic acid (gBAsp900) or alanine residue (gBAla900) substitution at Ser900 to mimic the phosphorylated or nonphosphorylated form, respectively. Immunofluorescence analysis of the trafficking of gB mutant molecules in fibroblasts infected with the HCMV recombinants revealed that gBAsp900 was localized to the TGN. In contrast, gBAla900 was partially mislocalized from the TGN, indicating that phosphorylation of gB at Ser900 was necessary for TGN localization. The increased TGN localization of gBAsp900 was due to a decreased transport of the molecule to post-TGN compartments. Remarkably, the substitution of an aspartic acid residue for Ser900 also resulted in an increase in levels of progeny virus production during HCMV infection of fibroblasts. Together, these results demonstrate that phosphorylation of gB at Ser900 is necessary for gB localization to the TGN, as well as for efficient viral replication, and further support the TGN as a site of HCMV envelopment.

Original languageEnglish (US)
Pages (from-to)285-293
Number of pages9
JournalJournal of Virology
Volume78
Issue number1
DOIs
StatePublished - Jan 2004

Fingerprint

Human herpesvirus 5
trans-Golgi Network
Casein Kinase II
Virus Replication
virus replication
glycoproteins
phosphorylation
Glycoproteins
Phosphorylation
Cytomegalovirus
aspartic acid
Aspartic Acid
fibroblasts
Fibroblasts
Simplexvirus glycoprotein B
non-specific serine/threonine protein kinase
Viruses
viruses
Cytomegalovirus Infections
Alanine

ASJC Scopus subject areas

  • Immunology

Cite this

Phosphorylation of Human Cytomegalovirus Glycoprotein B (gB) at the Acidic Cluster Casein Kinase 2 Site (Ser900) Is Required for Localization of gB to the trans-Golgi Network and Efficient Virus Replication. / Jarvis, Michael A.; Jones, Thomas R.; Drummond, Derek D.; Smith, Patsy P.; Britt, William J.; Nelson, Jay; Baldick, Carl J.

In: Journal of Virology, Vol. 78, No. 1, 01.2004, p. 285-293.

Research output: Contribution to journalArticle

Jarvis, Michael A. ; Jones, Thomas R. ; Drummond, Derek D. ; Smith, Patsy P. ; Britt, William J. ; Nelson, Jay ; Baldick, Carl J. / Phosphorylation of Human Cytomegalovirus Glycoprotein B (gB) at the Acidic Cluster Casein Kinase 2 Site (Ser900) Is Required for Localization of gB to the trans-Golgi Network and Efficient Virus Replication. In: Journal of Virology. 2004 ; Vol. 78, No. 1. pp. 285-293.
@article{5420b7710a114105bcbc5093d93b06d2,
title = "Phosphorylation of Human Cytomegalovirus Glycoprotein B (gB) at the Acidic Cluster Casein Kinase 2 Site (Ser900) Is Required for Localization of gB to the trans-Golgi Network and Efficient Virus Replication",
abstract = "Human cytomegalovirus (HCMV) glycoprotein B (gB), encoded by the UL55 open reading frame, is an essential envelope glycoprotein involved in cell attachment and entry. Previously, we identified residue serine 900 (Ser 900) as a unique site of reversible casein kinase 2 phosphorylation in the cytoplasmic domain of HCMV gB. We have also recently shown that gB is localized to the trans-Golgi network (TGN) in HCMV-permissive cells, thereby identifying the TGN as a possible site of virus envelopment. The aim of the current study was to determine the role of Ser900 phosphorylation in transport of gB to the TGN and in HCMV biogenesis. Recombinant HCMV strains were constructed that expressed gB molecules containing either an aspartic acid (gBAsp900) or alanine residue (gBAla900) substitution at Ser900 to mimic the phosphorylated or nonphosphorylated form, respectively. Immunofluorescence analysis of the trafficking of gB mutant molecules in fibroblasts infected with the HCMV recombinants revealed that gBAsp900 was localized to the TGN. In contrast, gBAla900 was partially mislocalized from the TGN, indicating that phosphorylation of gB at Ser900 was necessary for TGN localization. The increased TGN localization of gBAsp900 was due to a decreased transport of the molecule to post-TGN compartments. Remarkably, the substitution of an aspartic acid residue for Ser900 also resulted in an increase in levels of progeny virus production during HCMV infection of fibroblasts. Together, these results demonstrate that phosphorylation of gB at Ser900 is necessary for gB localization to the TGN, as well as for efficient viral replication, and further support the TGN as a site of HCMV envelopment.",
author = "Jarvis, {Michael A.} and Jones, {Thomas R.} and Drummond, {Derek D.} and Smith, {Patsy P.} and Britt, {William J.} and Jay Nelson and Baldick, {Carl J.}",
year = "2004",
month = "1",
doi = "10.1128/JVI.78.1.285-293.2004",
language = "English (US)",
volume = "78",
pages = "285--293",
journal = "Journal of Virology",
issn = "0022-538X",
publisher = "American Society for Microbiology",
number = "1",

}

TY - JOUR

T1 - Phosphorylation of Human Cytomegalovirus Glycoprotein B (gB) at the Acidic Cluster Casein Kinase 2 Site (Ser900) Is Required for Localization of gB to the trans-Golgi Network and Efficient Virus Replication

AU - Jarvis, Michael A.

AU - Jones, Thomas R.

AU - Drummond, Derek D.

AU - Smith, Patsy P.

AU - Britt, William J.

AU - Nelson, Jay

AU - Baldick, Carl J.

PY - 2004/1

Y1 - 2004/1

N2 - Human cytomegalovirus (HCMV) glycoprotein B (gB), encoded by the UL55 open reading frame, is an essential envelope glycoprotein involved in cell attachment and entry. Previously, we identified residue serine 900 (Ser 900) as a unique site of reversible casein kinase 2 phosphorylation in the cytoplasmic domain of HCMV gB. We have also recently shown that gB is localized to the trans-Golgi network (TGN) in HCMV-permissive cells, thereby identifying the TGN as a possible site of virus envelopment. The aim of the current study was to determine the role of Ser900 phosphorylation in transport of gB to the TGN and in HCMV biogenesis. Recombinant HCMV strains were constructed that expressed gB molecules containing either an aspartic acid (gBAsp900) or alanine residue (gBAla900) substitution at Ser900 to mimic the phosphorylated or nonphosphorylated form, respectively. Immunofluorescence analysis of the trafficking of gB mutant molecules in fibroblasts infected with the HCMV recombinants revealed that gBAsp900 was localized to the TGN. In contrast, gBAla900 was partially mislocalized from the TGN, indicating that phosphorylation of gB at Ser900 was necessary for TGN localization. The increased TGN localization of gBAsp900 was due to a decreased transport of the molecule to post-TGN compartments. Remarkably, the substitution of an aspartic acid residue for Ser900 also resulted in an increase in levels of progeny virus production during HCMV infection of fibroblasts. Together, these results demonstrate that phosphorylation of gB at Ser900 is necessary for gB localization to the TGN, as well as for efficient viral replication, and further support the TGN as a site of HCMV envelopment.

AB - Human cytomegalovirus (HCMV) glycoprotein B (gB), encoded by the UL55 open reading frame, is an essential envelope glycoprotein involved in cell attachment and entry. Previously, we identified residue serine 900 (Ser 900) as a unique site of reversible casein kinase 2 phosphorylation in the cytoplasmic domain of HCMV gB. We have also recently shown that gB is localized to the trans-Golgi network (TGN) in HCMV-permissive cells, thereby identifying the TGN as a possible site of virus envelopment. The aim of the current study was to determine the role of Ser900 phosphorylation in transport of gB to the TGN and in HCMV biogenesis. Recombinant HCMV strains were constructed that expressed gB molecules containing either an aspartic acid (gBAsp900) or alanine residue (gBAla900) substitution at Ser900 to mimic the phosphorylated or nonphosphorylated form, respectively. Immunofluorescence analysis of the trafficking of gB mutant molecules in fibroblasts infected with the HCMV recombinants revealed that gBAsp900 was localized to the TGN. In contrast, gBAla900 was partially mislocalized from the TGN, indicating that phosphorylation of gB at Ser900 was necessary for TGN localization. The increased TGN localization of gBAsp900 was due to a decreased transport of the molecule to post-TGN compartments. Remarkably, the substitution of an aspartic acid residue for Ser900 also resulted in an increase in levels of progeny virus production during HCMV infection of fibroblasts. Together, these results demonstrate that phosphorylation of gB at Ser900 is necessary for gB localization to the TGN, as well as for efficient viral replication, and further support the TGN as a site of HCMV envelopment.

UR - http://www.scopus.com/inward/record.url?scp=0346908981&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0346908981&partnerID=8YFLogxK

U2 - 10.1128/JVI.78.1.285-293.2004

DO - 10.1128/JVI.78.1.285-293.2004

M3 - Article

C2 - 14671110

AN - SCOPUS:0346908981

VL - 78

SP - 285

EP - 293

JO - Journal of Virology

JF - Journal of Virology

SN - 0022-538X

IS - 1

ER -