FIGURE 3.

ADAM-mediated corin shedding. HEK 293 and HL-1 cells expressing recombinant corin were treated with vehicle, ionomycin (IM) (A) or PMA (B). Corin fragments in the conditioned medium (CM) and cell lysate (LS) were analyzed by Western blotting. C, expression of human (h) and mouse (m) ADAM10 and ADAM17 mRNAs in parental HEK 293 and HL-1 cells was confirmed by RT-PCR. HEK 293 (D) and HL-1 (E) cells expressing corin were transfected with single or pooled siRNAs against the human or mouse ADAM10 or ADAM17 genes. The production of the ∼180-kDa fragment (arrows) in the medium was reduced in ADAM10 siRNA-treated cells, as shown by Western blotting. Controls included non-targeting siRNAs pool or siRNAs pools against the human and mouse GAPDH genes. The reduction of ADAM10 (proform (P) and mature form (m) (arrow heads)), ADAM17, and GAPDH proteins in transfected cells was shown by Western blotting. Full-length (FL) corin in cell lysate also was shown. Data are from representative experiments that were repeated at least three times.