|
||
By

From the * Center for Cancer Research, Department of Biology, Massachusetts Institute of Technology,
Cambridge, Massachusetts 02139; and Human cytomegalovirus downregulates the expression of human class I major histocompatibility complex (MHC) molecules by accelerating destruction of newly synthesized class I heavy
chains. The HCMV genome contains at least two genes, US11 and US2, each of which encode
a product sufficient for causing the dislocation of newly synthesized class I heavy chains from the
lumen of the endoplasmic reticulum to the cytosol. Based on a comparison of their abilities to
degrade the murine class I molecules H-2Kb, Kd, Db, Dd, and Ld, the US11 and US2 gene
products have non-identical specificities for class I molecules. Specifically, in human astrocytoma cells (U373-MG) transfected with the US11 gene, the Kb, Db, Dd, and Ld molecules expressed via recombinant vaccinia virus are rapidly degraded, whereas in US2-transfected cells,
only Db and Dd are significantly destabilized. The diversity in HCMV-encoded functions that
interfere with class I-restricted presentation likely evolved in response to the polymorphism of
the MHC.
Department of Molecular Biology, Infectious Diseases
Section, Wyeth-Ayerst Research, Pearl River, New York 10965
This article has been cited by other articles:
| TABLE OF CONTENTS |
|