Cell proteins can restrict the replication of viruses. Here, we identify the cellular BclAF1 protein as a human cytomegalovirus restriction factor and describe two independent mechanisms the virus uses to decrease its steady-state levels. Immediately following infection, the viral pp71 and UL35 proteins, which are delivered to cells within virions, direct the proteasomal degradation of BclAF1. Although BclAF1 reaccumulates through the middle stages of infection, it is subsequently down-regulated at late times by miR-UL112-1, a virus-encoded microRNA. In the absence of BclAF1 neutralization, viral gene expression and replication are inhibited. These data identify twotemporally andmechanistically distinct functions used byhuman cytomegalovirus to down-regulate a cellular antiviral protein.
|Number of pages||6|
|Journal||Proceedings of the National Academy of Sciences of the United States of America|
|State||Published - Jun 12 2012|
- Innate immunity
- Intrinsic immunity