Effect of mutations in the N-terminal region of AnxA1 on cleavage by PR3. (A) Schematic representation of AnxA1 domains, highlighting the 3 PR3 cleavages sites in the N-terminal region; N-terminal domain sequences of AnxA1 and AnxA1 mutants. (B) Western blot analysis of MFAnxA1 mutants expression in HEK293 transfected cells: lysates were immunoblotted (IB) with anti–c-Myc, anti-Flag, and anti-AnxA1 antibodies. (C) Immunoprecipitation (IP) for c-Myc products were incubated for 30 minutes at 37°C with PR3 (50, 100, or 200 mU) and intact MFAnxA1 recovered by immunoblotting for c-Myc. Data are representative of 3 distinct analyses performed with distinct preparations of lysates.