Expression of GFP-tagged and RFP-tagged mProVII variants. Upper panel shows Western blot analysis of mProVII variants secreted from selected clones of HEK-293 cells co-transfected with RFP-tagged WT chains and GFP-tagged mutant chains. In each set of the upper panel, the mProVII chains from corresponding samples were detected with anti-NC1 specific antibodies, anti-RFP or anti-GFP-specific antibodies. Lower panel presents a schematic of mProVII variants. Symbols: G2575R, R2622Q, and G2623C; specific amino acid substitutions in mProVII chains, NC1, TH, and NC2; the N-terminal, triple-helical, and the C-terminal domains of mProVII molecules, respectively. GFP and RFP are depicted as green or red cylinders, respectively.