Fig. 1.
Processing of PC7 substrates. Cleavage of human transferrin receptor 1 (hTfR1), human proSortilin and mouse proApolipoprotein F (proApoF) by wild type (WT) human PC7 and its R504H mutant or by rat PC7. (A) Comparison of human, mouse, rat and xenopus (Xen.) PC7 sequences. (B–D) Western blot analysis of the lysates and 20 h conditioned media of HuH7 cells co-transfected with 800 ng of hTfR1-V5 and either 800 ng (B, D) or 8 ng (C) of empty vector, human PC7 WT or its R504H mutant or rat PC7. The separated proteins were revealed using mAb V5-HRP, PC7 or β-actin antibodies and a rabbit HRP-conjugated secondary antibody. (E) Western blot analysis of cell lysates from HEK293 cells transiently transfected with human proSortilin-c-Myc and either empty vector, human PC7 WT or its R504H mutant. Proteins were revealed using mouse c-Myc, rabbit PC7 or rabbit β-actin antibodies and the corresponding HRP-conjugated secondary antibody. (F) Western blot analysis of lysates and 48 h conditioned media from mouse primary hepatocytes co-transfected with human or mouse proApoF-V5 and either empty vector, human PC7 WT or its R504H mutant. The separated proteins were revealed using mAb V5-HRP, PC7 or β-actin antibodies and a rabbit HRP-conjugated secondary antibody.