Fig. 4.
Processing of human S100A10 (p11) by MMP-2. A, amino acid sequence of S100A10 showing the natural N-terminus of the mature protein (green) and an MMP-2-generated neo-N-terminus (blue) identified by CLIP-TRAQ-TAILS. B, mass spectra assigned to the natural N-terminus and neo-N-terminus of S100A10, respectively. Insets show a close-up of the CLIP-TRAQ reporter ion region indicating the presence of the original mature N-terminal peptide in both samples and the neo-N-terminus only in the MMP-2-treated (CLIP-TRAQ-113) sample. C, MMP-2 cleavage of S100A10 analyzed by 15% Tris-Tricine SDS-PAGE. Arrows show full-length and cleaved S100A10. Both bands were sequenced by Edman degradation and shown to be the N-terminal part of either unprocessed or C-terminally truncated protein as indicated by the N-terminal sequence (asterisks). Notably, the lower band was consistently increased in amount after incubation with MMP-2.