The African swine fever virus lectin EP153R modulates the surface membrane expression of MHC class I antigens

摘要

We have modeled a 3D structure for the C-type\udlectin domain of the African swine fever virus protein\udEP153R, based on the structure of CD69, CD94 and Ly49A\udcell receptors, and this model predicts that a dimer of\udEP153R may establish an asymmetric interaction with one\udMHC-I molecule. A functional consequence of this interaction\udcould be the modulation of MHC-I expression. By\udusing both transfection and virus infection experiments, we\uddemonstrate here that EP153R inhibits MHC-I membrane\udexpression, most probably by impairing the exocytosis\udprocess, without affecting the synthesis or glycosylation of\udMHC antigens. Interestingly, the EP153-mediated control\udof MHC requires the intact configuration of the lectin\uddomain of the viral protein, and specifically the R133\udresidue. Interference of EP153R gene expression during\udvirus infection and studies using virus recombinants with\udthe EP153R gene deleted further support the inhibitory role\udof the viral lectin on the expression of MHC-I antigens.