Affiliation:
1. Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon 97239-3098
Abstract
ABSTRACT
The human cytomegalovirus (HCMV) glycoprotein US2 specifically binds to major histocompatibility complex (MHC) class I heavy chain (HC) and class II proteins DRα and DMα, triggering their degradation by proteasomes. Effects of US2 on class II proteins were originally characterized in HCMV- or adenovirus vector-infected U373 astroglioma cells. Here, we have extended characterization of US2-mediated degradation of class II DRα to two other cell lines, including biologically relevant epithelial cells. Comparison of the effects of US2 in cells expressing both class I and II proteins demonstrated only a slight preference for class I HC. Moreover, US2 caused degradation of DRα and DMα when these proteins were expressed by transfection without DRβ, invariant chain (Ii), or DMβ. Therefore, US2 binds to α chains of DR and DM and triggers endoplasmic reticulum degradation without formation of class II DR αβ/Ii or DM αβ complexes. Similar levels of degradation of class II α were observed in cells expressing vastly different amounts of class II, suggesting that cellular factors, other than class II, were limiting. We concluded that US2 has broad effects in a variety of cells that express both class I and II proteins and is relevant to HCMV infection in vivo.
Publisher
American Society for Microbiology
Subject
Virology,Insect Science,Immunology,Microbiology
Cited by
29 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献