Figure 6
From: Experimental detection of proteolytic activity in a signal peptide peptidase of Arabidopsis thaliana
Characterization of the cleavage site in the myc-Prl-PP-FLAG peptide. Products of the myc-Prl-PP-FLAG peptide proteolysis by various SPP proteins and standard peptides Prl-23 were separated by a Tris/Tricine urea gel and detected with an anti-myc antibody. (A) Structure of the substrate Prl-23: Prl-23 is a N-terminal fragment of myc-Prl-PP-FLAG peptide composed of 23 amino acid residues. (B) Lane 1, synthesized marker fragment of Prl-23; lane 2, the membrane fraction of HEK293T cells; lane 3, HEK293T cells with 10 μM (Z-LL)2-ketone inhibitor; lane 4, membrane fraction of yeast cells overexpressing HsSPP-GFP; lane 5, membrane fraction of “Deep” cell extracts; lane 6, the membrane fraction of yeast cells overexpressing AtSPP. The black arrow indicates myc-Prl-PP-FLAG as the original peptide and the white arrow indicates the position of the proteolytic fragment.