(A) Representative images of COS7 cells expressing COP1-3xFLAG (green) co-transfected with empty vector, GFP, or the indicated GFP-TRIB1 constructs (red). Cells were stained with anti-FLAG (Sigma) and anti-mouse Alexa Fluor 568. Nuclei were counterstained with DAPI (blue). Scale bar, 10 µm. 