The recognition of viral peptides in the context of MHCI proteins by cytotoxic T lymphocytes is a key event for eliminating virus-infected cells. Prior to presenting peptides at the cell surface, MHCI proteins must undergo a stringent maturation process in the lumen of the endoplasmic reticulum by transiently interacting with members of the peptide loading complex (PLC). After dissociation from the PLC, peptide-bound MHCI proteins transit through the Golgi to the surface following the secretory pathway. The secretory pathway is known to involve a series of membrane bound compartments with specialized functions in cargo transport;however, many of the molecular details of this pathway have yet to be elucidated. To resolve outstanding questions of MHCI biosynthesis along the secretory pathway, we will use viral immune evasion proteins as probes for physiologic pathways. Viruses encode a plethora of immune evasion proteins that exploit a surprising diversity of physiologic pathways to block antigen presentation and they do so with great specificity and potency. These properties make immune evasion proteins highly effective probes for defining molecular pathways of protein quality control that are of particular relevance to MHCI function. In this grant, we will use immune evasion proteins to probe i) how misfolded MHCI proteins are identified and translocated from the ER lumen to the cytosol, ii) mechanisms of ER to Golgi recycling and their importance for MHC quality control and initiating ERAD, and iii) the physiologic role of ubiquitination of lysine vs. serine MHCI residues for ERAD and recycling from the plasma membrane. The proposed experiments will use cell biological, biochemical, and structural approaches employed by collaborative efforts of the Hansen and Fremont labs.

Public Health Relevance

Viruses express proteins that block their detection by immune cells of the host. Furthermore, these viral immune evasion proteins efficiently exploit physiologic pathways, thus making them highly effective probes for molecular dissection of mechanisms of pathogen recognition by immune cells. Experiments in this grant will define the mechanisms used by several different herpesvirus or poxvirus immune evasion proteins to target host proteins and thereby block specific cellular pathways of critical importance for pathogen detection.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI019687-30
Application #
8582050
Study Section
Cellular and Molecular Immunology - B Study Section (CMIB)
Program Officer
Beisel, Christopher E
Project Start
2011-12-01
Project End
2016-11-30
Budget Start
2013-12-01
Budget End
2014-11-30
Support Year
30
Fiscal Year
2014
Total Cost
$342,000
Indirect Cost
$117,000
Name
Washington University
Department
Pathology
Type
Schools of Medicine
DUNS #
068552207
City
Saint Louis
State
MO
Country
United States
Zip Code
63130
Kim, Sojung; Pinto, Amelia K; Myers, Nancy B et al. (2014) A novel T-cell receptor mimic defines dendritic cells that present an immunodominant West Nile virus epitope in mice. Eur J Immunol 44:1936-46
Lubman, Olga Y; Cella, Marina; Wang, Xinxin et al. (2014) Rodent herpesvirus Peru encodes a secreted chemokine decoy receptor. J Virol 88:538-46
Mage, Michael G; Dolan, Michael A; Wang, Rui et al. (2013) A structural and molecular dynamics approach to understanding the peptide-receptive transition state of MHC-I molecules. Mol Immunol 55:123-5
McCoy 4th, William H; Wang, Xiaoli; Yokoyama, Wayne M et al. (2013) Cowpox virus employs a two-pronged strategy to outflank MHCI antigen presentation. Mol Immunol 55:156-8
Wang, Xiaoli; Yu, Y Y Lawrence; Myers, Nancy et al. (2013) Decoupling the role of ubiquitination for the dislocation versus degradation of major histocompatibility complex (MHC) class I proteins during endoplasmic reticulum-associated degradation (ERAD). J Biol Chem 288:23295-306
Wang, Xiaoli; Herr, Roger A; Hansen, Ted H (2012) Ubiquitination of substrates by esterification. Traffic 13:19-24
Herr, Roger A; Wang, Xiaoli; Loh, Joy et al. (2012) Newly discovered viral E3 ligase pK3 induces endoplasmic reticulum-associated degradation of class I major histocompatibility proteins and their membrane-bound chaperones. J Biol Chem 287:14467-79
Herr, Roger A; Harris, Jennifer; Fang, Shengyun et al. (2009) Role of the RING-CH domain of viral ligase mK3 in ubiquitination of non-lysine and lysine MHC I residues. Traffic 10:1301-17
Wang, Xiaoli; Herr, Roger A; Rabelink, Martijn et al. (2009) Ube2j2 ubiquitinates hydroxylated amino acids on ER-associated degradation substrates. J Cell Biol 187:655-68
Hansen, Ted H; Bouvier, Marlene (2009) MHC class I antigen presentation: learning from viral evasion strategies. Nat Rev Immunol 9:503-13

Showing the most recent 10 out of 66 publications