Extracts of unstimulated AdV-infected myocytes individually expressing FLAG–MST3(FL), FLAG–MST3(Δ314–431), FLAG–MST3(Δ341–431) and FLAG–MST3(Δ377–431) were combined and subjected to gel-filtration chromatography using Sephacryl S200HR. (A) Immunoblotting of column fractions with anti-FLAG antibodies. The lowest mobility band is FLAG–MST3(FL) and the highest is FLAG–MST3(Δ314–431). Lane S is a standard containing combined unfractionated extracts from myocytes expressing the four MST3 species. (B) Elution profile showing quantification of band intensities. ●, FLAG–MST3(FL); ■, FLAG–MST3(Δ377–431); ▲, FLAG–MST3(Δ341–431); and ◆, FLAG–MST3(Δ314–431). (C) The Sephacryl S200HR column was standardized with proteins of known Stokes radii (taken from the literature). 1: IgG, 50.0 Å; 2: BSA dimer, 47.5 Å; 3: rabbit muscle phosphorylase b monomer, 37.0 Å; 4: BSA monomer, 35.0 Å; 5: ovalbumin, 30.5 Å; 6: β-lactoglobin, 26.7 Å; 7: cytochrome c, 17.0 Å. Experiments were repeated three times with different myocyte preparations with similar results.