Left: HEK293 cells transfected with a mCherry (red) were stained with chicken antibody to mCherry (green). Blue: DAPI nuclear stain. Transfected cells appear bright red, and co-stain for mCherry chicken antibody. Superimposition of both signals results in yellow-orange colour. Right: Western blot analysis of transfected and control HEK293 cell lysates, and recombinant proteins with chicken antibody to mCherry (1:2,000, green). [1] protein standard, [2] HEK293 control, [3] HEK293 cells transfected with mCherry, [4] recombinant mCherry protein, [5] recombinant GFP protein, [6] HEK293 transfected with GFP. The major band at about 30 kDa corresponds to mCherry protein and the slightly larger recombinant form runs at about 33 kDa due to presence of a His tag and other vector derived sequences. No cross-reactivity with GFP protein is observed. The same blot was simultaneously probed with a mouse antibody to HSP60 (red), which reveals a band at 60 kDa only in cell lysates.