Open AccessPhysical Association of the K3 Protein of Gamma-2 Herpesvirus 68 with Major Histocompatibility Complex Class I Molecules with Impaired Peptide and β2-Microglobulin Assembly
Author(s) -
Yanbo Yu,
Michael Harris,
Lonnie Lybarger,
Lisa A. Kimpler,
Nancy B. Myers,
Herbert W. Virgin,
Ted H. Hansen
Publication year - 2002
Publication title -
journal of virology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.617
H-Index - 292
eISSN - 1070-6321
pISSN - 0022-538X
DOI - 10.1128/jvi.76.6.2796-2803.2002
Subject(s) - biology , beta 2 microglobulin , calreticulin , major histocompatibility complex , mhc class i , microbiology and biotechnology , cd74 , peptide , transporter associated with antigen processing , antigen processing , genetics , immune system , biochemistry , immunology , endoplasmic reticulum
To persist in the presence of an active immune system, viruses encode proteins that decrease expression of major histocompatibility complex class I molecules by using a variety of mechanisms. For example, murine gamma-2 herpesvirus 68 expresses the K3 protein, which causes the rapid turnover of nascent class I molecules. In this report we show that certain mouse class I alleles are more susceptible than others to K3-mediated down regulation. Prior to their rapid degradation, class I molecules in K3-expressing cells exhibit impaired assembly with beta(2)-microglobulin. Furthermore, K3 is detected predominantly in association with class I molecules lacking assembly with high-affinity peptides, including class I molecules associated with the peptide loading complex TAP/tapasin/calreticulin. The detection of K3 with class I assembly intermediates raises the possibility that molecular chaperones involved in class I assembly are involved in K3-mediated class I regulation.