Figure 3.

Identification of two unique C-terminal mouse FL JP2 cleavage fragments by SNAP-tagging and in-gel flourescent product detection. Recombinantly expressed, puried C-terminally SNAP-tagged JP2 was labeled with the high-affinity SNAP ligand 647-SiR and digested with 1.0 U/ml Calpain-1 or 1.0 U/ml Calpain-2 for 30 min at 30 °C. Digested samples were subjected to SDS-PAGE, Coomassie staining, in-gel 647-SiR flourescence detection, and immunoblotting as indicated. Two unique C-terminal fragments were identified by 647-SiR in-gel fluorescence, and each confirmed by Coomassie staining and immunoblotting, namely 647-SiR-tagged CT₁ and CT₂.