Functional Analysis of the Murine Cytomegalovirus G Protein-coupled Receptor M33

Bibliographic Details
Main Author: Sherrill, Joseph D.
Language:English
Published: University of Cincinnati / OhioLINK 2008
Subjects:
M33
Online Access:http://rave.ohiolink.edu/etdc/view?acc_num=ucin1225745444
id ndltd-OhioLink-oai-etd.ohiolink.edu-ucin1225745444
record_format oai_dc
spelling ndltd-OhioLink-oai-etd.ohiolink.edu-ucin12257454442021-08-03T06:12:52Z Functional Analysis of the Murine Cytomegalovirus G Protein-coupled Receptor M33 Sherrill, Joseph D. Biochemistry Microbiology Molecular Biology Virology G protein GPCR cytomegalovirus MCMV M33 CREB protein kinase C Several members of the herpesvirus family encode seven transmembrane-spanning proteins that share significant homology with the cellular G protein-coupled receptors (GPCRs). These viral GPCR homologs stimulate both G protein-dependent and G protein-independent signaling pathways reminiscent of cellular GPCRs. By mimicking host cell proteins and altering intricate signaling networks, viral GPCRs are often viewed as immune evasion genes, enhancing viral replication and persistence within the infected host. The studies described herein characterize the signaling activities and regulation of the viral GPCR homolog M33 encoded by the murine cytomegalovirus (MCMV). Cytomegaloviruses are species-specific opportunistic pathogens that cause disease within the immunocompromised host. MCMV has been used extensively as a model for studying human cytomegalovirus (HCMV) pathogenesis in vivo, with M33 playing an essential role in MCMV dissemination and replication within the host salivary gland. We have identified the first ten amino acids of M33 as critical for proper M33 post-translational modification, cell surface expression, as well as the activation of G protein signaling events. We show through mutational analysis that a conserved GPCR signaling motif of M33 is required for G protein signaling yet is not involved in other M33 signaling activities including phosphorylation of the mitogen-activated protein kinase p38 and activation of the transcription factor NF-κB, indicating M33 possesses G protein-independent signaling abilities. Additionally, we have identified a role of cellular GPCR regulatory proteins in attenuating M33 G protein signaling through a dual mechanism involving both receptor phosphorylation and sequestration of activated G proteins. Lastly, in order to understand M33 signaling and regulation in the context of MCMV infection we made various mutations of the M33 ORF within the MCMV genome and show that M33 and its ability to activate a G<sub>q/11</sub>/PLC-β/PKC pathway appears to be required for efficient MCMV replication within the salivary gland. Further characterizations of these recombinant viruses will ultimately allow for the study of M33 function with regards to its contribution in MCMV pathogenesis in vivo. By understanding the G protein signaling pathways and regulatory events characteristic of viral GPCRs we may attain a greater appreciation of these processes as potential therapeutic targets for treating HCMV infection. 2008 English text University of Cincinnati / OhioLINK http://rave.ohiolink.edu/etdc/view?acc_num=ucin1225745444 http://rave.ohiolink.edu/etdc/view?acc_num=ucin1225745444 unrestricted This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws.
collection NDLTD
language English
sources NDLTD
topic Biochemistry
Microbiology
Molecular Biology
Virology
G protein
GPCR
cytomegalovirus
MCMV
M33
CREB
protein kinase C
spellingShingle Biochemistry
Microbiology
Molecular Biology
Virology
G protein
GPCR
cytomegalovirus
MCMV
M33
CREB
protein kinase C
Sherrill, Joseph D.
Functional Analysis of the Murine Cytomegalovirus G Protein-coupled Receptor M33
author Sherrill, Joseph D.
author_facet Sherrill, Joseph D.
author_sort Sherrill, Joseph D.
title Functional Analysis of the Murine Cytomegalovirus G Protein-coupled Receptor M33
title_short Functional Analysis of the Murine Cytomegalovirus G Protein-coupled Receptor M33
title_full Functional Analysis of the Murine Cytomegalovirus G Protein-coupled Receptor M33
title_fullStr Functional Analysis of the Murine Cytomegalovirus G Protein-coupled Receptor M33
title_full_unstemmed Functional Analysis of the Murine Cytomegalovirus G Protein-coupled Receptor M33
title_sort functional analysis of the murine cytomegalovirus g protein-coupled receptor m33
publisher University of Cincinnati / OhioLINK
publishDate 2008
url http://rave.ohiolink.edu/etdc/view?acc_num=ucin1225745444
work_keys_str_mv AT sherrilljosephd functionalanalysisofthemurinecytomegalovirusgproteincoupledreceptorm33
_version_ 1719432880284762112