Positive Role of Promyelocytic Leukemia Protein in Type I Interferon Response and Its Regulation by Human Cytomegalovirus
Fig 6
Association of IE1 with STAT1, STAT2, HDAC1, HDAC2, and PML during infection and the binding of IE1(Δ290–320) with STAT2 and HDACs.
(A) HF cells were mock-infected (-) or infected (+) with HCMV (Towne) at an MOI of 2 IFU per cell. At 24 h after infection, total cell lysates were prepared and immunoprecipitated with anti-IE1 antibody (CH443); immunoprecipitation with mouse IgG was used as a negative control. The samples were subjected to SDS-PAGE and immunoblotted with antibodies for the indicated proteins (left panels). Immunoblot assays were also performed with total cell lysates to confirm protein expression levels (right panels). (B and C) HF cells were mock-infected or infected with wild-type, IE1(Δ290–320), or IE1(Δ421–475) mutant virus at an MOI of 2. At 12 h, total cell lysates were prepared and immunoprecipitated with anti-IE1 antibody (CH443) and immunoblotted with anti-STAT2 antibody (B) or with anti-HDAC1 or anti-HDAC2 antibodies (C). Total cell lysates were also immunoblotted with antibodies for IE1 (CH443), STAT2, HDAC1, and HDAC2 to confirm protein expression levels. (D) 293T cells were cotransfected with plasmids expressing HA-tagged wild-type, Δ290–320, or Δ290–320/Δ421–475 IE1 and myc-HDAC1, myc-HDAC2, myc-HDAC3, or myc-HDAC6 as indicated. At 48 h, whole cell lysates were prepared and immunoprecipitated with anti-Myc antibody and immunoblotted with anti-HA antibody. Levels of HA-IE1 and myc-HDAC proteins in whole cell lysates were determined by immunoblotting.