US12 a key factor in the evasion of cellular immune response against HSV-infected cells. Specific inhibition of the transporter associated with antigen processing (TAP) by US12 prevents peptide transport into the endoplasmic reticulum and subsequent loading of major histocompatibility complex (MHC) class I molecules. US12 is comprised of three helices and is associated with cellular membranes.
Jiyao W et al.(2023). "The conserved domain database in 2023.",