Fig. 2

Ectodomain shedding induced the generation of the epithin/PRSS14 intracellular domain. a Schematic diagram of the epithin/PRSS14 domain structure, its possible proteolytic fragments, and epitopes of antibodies used in this study are illustrated. TM, transmembrane domain; SEA, sperm protein, enterokinase, and agrin domain; CUB1, CUB2, complement subcomponent C1r/C1s domain; 1, 2, 3, 4, low-density lipoprotein receptor class A repeats. b The 427 cells were treated with or without PMA and shed epithin/PRSS14 (Epi-S′) was analyzed using mAb5. Cell-bound epithin/PRSS14 (Epi-S), NTF, and EICD were detected by immunoprecipitation and subsequent Western blot with mAb5 and anti-N antibody under each condition. CS, control serum. c After the antigen of anti-N antibody (Gly12-Arg25) was added or left out of the immunoprecipitation reaction, Epi-S, NTF, and EICD in the anti-N antibody, immunoprecipitates were analyzed as in b. d The proteolytic fragment of human epithin/PRSS14 was analyzed using MCF7 human breast cancer cells. e The 427 cells were treated with PMA and/or TAPI-0, and each fragment was analyzed as in b. Arrowhead and arrow indicate NTF and EICD, respectively