Recombinant proteins prepared in this study and comparison with membrane EPCR and plasma sEPCR resulting from shedding by ADAM17. The amino acid numbering starts at Met + 1. The signal peptide (hatched stretch) that is cut before protein addressing to the membrane (EPCR and sEPCR) or before protein secretion (rEPCRsol and rEPCRisoform) comprises amino acids 1 to 17. The C-terminal amino acid of plasma EPCR (sEPCR) is unknown (↔). The gray stretch denotes the putative transmembrane domain predicted by TMHMM Server, version 2.0 (panel below Membrane EPCR). The hatched gray stretch corresponds to the new C-terminal part of EPCRisoform (relative to membrane EPCR and sEPCR) lacking the transmembrane domain, owing to mRNA truncation.