Left: Analysis of GFP fusion protein-transfected HEK293 cells by Immunocytochemistry. GFP expression (green) was detected with goat antibody to GFP (red, 1:5,000). Blue: Hoechst nuclear stain. The goat antibody reveals GFP protein expressed only in transfected cells, and as a result these cells appear yellow in color. Top: merged image; bottom panel: individual fluorescence channels. Right: Western blot analysis of GFP expression (green) in transfected HEK293 cells with goat anti-GFP antibody (1:1,000). Lane 1: molecular weight marker; Lane 2: non-transfected control cells; Lane 3: GFP-transfected cells; Lane 4: mCherry-transfected cells. A strong band at ~27 kDa corresponds to GFP protein detected only in cells transfected with GFP construct. This antibody does not recognize the mCherry protein.