FIGURE 3.

Interaction between the acidic cluster motifs in BBLF1 and BGLF2. (A) Sequences of BBLF1 and NDE-BBLF1, SDE-BBLF1, and NEDSDE-BBLF1. Acidic clusters of BBLF1 are highlighted. (B) 293T cells were cotransfected with pBGLF2-GFP and pBBLF1-Flag or a plasmid that expressed BBLF1 with an NDE, SDE, or NDESDE mutation. Proteins in the lysates were immunoprecipitated (IP) at 48 h post-transfection using anti-Flag antibody or precipitated using GFP-Trap and analyzed by immunoblotting with anti-GFP or anti-Flag antibodies, as indicated. A7 cells were cotransfected with plasmids that express BGLF2-GFP (C) or GFP (D) and BBLF1 or its mutant derivatives. Cells were fixed at 48 h post-transfection. Indirect immunofluorescence staining was performed using anti-BBLF1 and anti-TGN46 antibodies and was followed by incubation with fluorescently labeled secondary antibodies. DAPI staining (blue) revealed the nuclei. Images were captured and analyzed using a Leica SP5 confocal laser-scanning microscope. Arrow: BGLF2-GFP was recruited to TGN.