PMP comparing wild-type and US2-deficient HCMV shows a requirement for US2 in the downregulation of cell surface targets.

<p>(A) Scatter plots of proteins identified in PMP and quantified by 2 or more unique peptides. Fold change (HFF infected with wild-type HCMV versus HFF infected with ΔUS2 HCMV) is shown as log₂ ratio on the x axis and the summed peptide intensity on the y-axis as log₁₀. Proteins unaltered by HCMV US2 gene deletion locate to the center of the plots (0-fold change), whereas proteins left or right of center represent respectively proteins down- or up-regulated by HCMV in a US2-dependent manner. Significance B was used to estimate p values. (<b>B</b>) US2 is required for integrin and thrombomodulin downregulation during HCMV infection. HFF cells infected with GFP tagged HCMV ΔUL16-18 or ΔUL16-18ΔUS1-11 (moi 0.5) were analyzed by cytofluorometric analysis of the indicated proteins at 72 hours post-infection. (<b>C</b>) HFFs infected with HCMV wild-type or ΔUS2 (moi 0.5) were analyzed by flow cytometry at 72 hours post-infection. Cell surface staining for MHC-I enabled gating for HCMV infected (MHC-I^lo) cells (left panel) and subsequent analysis of the integrin and thrombomodulin expression (right panels). See also <b><a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1004811#ppat.1004811.s007" target="_blank">S3 Table</a></b>.