TY - JOUR
T1 - Human cytomegalovirus US28 facilitates cell-to-cell viral dissemination
AU - Noriega, Vanessa M.
AU - Gardner, Thomas J.
AU - Redmann, Veronika
AU - Bongers, Gerold
AU - Lira, Sergio A.
AU - Tortorella, Domenico
PY - 2014/3/12
Y1 - 2014/3/12
N2 - Human cytomegalovirus (HCMV) encodes a number of viral proteins with homology to cellular G protein-coupled receptors (GPCRs). These viral GPCRs, including US27, US28, UL33, and UL78, have been ascribed numerous functions during infection, including activating diverse cellular pathways, binding to immunomodulatory chemokines, and impacting virus dissemination. To investigate the role of US28 during virus infection, two variants of the clinical isolate TB40/E were generated: TB40/E-US28YFP expressing a C-terminal yellow fluorescent protein tag, and TB40/E-FLAGYFP in which a FLAG-YFP cassette replaces the US28 coding region. The TB40/E-US28YFP protein localized as large perinuclear fluorescent structures at late times post-infection in fibroblasts, endothelial, and epithelial cells. Interestingly, US28YFP is a non-glycosylated membrane protein throughout the course of infection. US28 appears to impact cell-to-cell spread of virus, as the ΔUS28 virus (TB40/E-FLAGYFP) generated a log-greater yield of extracellular progeny whose spread could be significantly neutralized in fibroblasts. Most strikingly, in epithelial cells, where dissemination of virus occurs exclusively by the cell-to-cell route, TB40/E-FLAGYFP (ΔUS28) displayed a significant growth defect. The data demonstrates that HCMV US28 may contribute at a late stage of the viral life cycle to cell-to-cell dissemination of virus.
AB - Human cytomegalovirus (HCMV) encodes a number of viral proteins with homology to cellular G protein-coupled receptors (GPCRs). These viral GPCRs, including US27, US28, UL33, and UL78, have been ascribed numerous functions during infection, including activating diverse cellular pathways, binding to immunomodulatory chemokines, and impacting virus dissemination. To investigate the role of US28 during virus infection, two variants of the clinical isolate TB40/E were generated: TB40/E-US28YFP expressing a C-terminal yellow fluorescent protein tag, and TB40/E-FLAGYFP in which a FLAG-YFP cassette replaces the US28 coding region. The TB40/E-US28YFP protein localized as large perinuclear fluorescent structures at late times post-infection in fibroblasts, endothelial, and epithelial cells. Interestingly, US28YFP is a non-glycosylated membrane protein throughout the course of infection. US28 appears to impact cell-to-cell spread of virus, as the ΔUS28 virus (TB40/E-FLAGYFP) generated a log-greater yield of extracellular progeny whose spread could be significantly neutralized in fibroblasts. Most strikingly, in epithelial cells, where dissemination of virus occurs exclusively by the cell-to-cell route, TB40/E-FLAGYFP (ΔUS28) displayed a significant growth defect. The data demonstrates that HCMV US28 may contribute at a late stage of the viral life cycle to cell-to-cell dissemination of virus.
KW - BAC recombineering
KW - Human cytomegalovirus
KW - Membrane protein biology
KW - Viral GPCR US28
KW - Virus dissemination
KW - Virus growth
UR - http://www.scopus.com/inward/record.url?scp=84897814437&partnerID=8YFLogxK
U2 - 10.3390/v6031202
DO - 10.3390/v6031202
M3 - Article
C2 - 24625810
AN - SCOPUS:84897814437
SN - 1999-4915
VL - 6
SP - 1202
EP - 1218
JO - Viruses
JF - Viruses
IS - 3
ER -