Cleaves the alpha-chain at multiple sites and the beta-chain between 'Lys-53' and 'Lys-54' but not the gamma-chain of fibrinogen and therefore does not initiate the formation of the fibrin clot and does not cause the fibrinolysis directly. It does not cleave (activate) prothrombin and plasminogen but converts the inactive single chain urinary plasminogen activator (pro-urokinase) to the active two chain form. Activates coagulation factor VII (PubMed:8827452, PubMed:10754382, PubMed:11217080). May function as a tumor suppressor negatively regulating cell proliferation and cell migration (PubMed:26222560). Heterodimer; disulfide-linked. Heterodimer of a 50 kDa heavy and a 27 kDa light chain linked by a disulfide bond (By similarity). Secreted as an inactive single-chain precursor and is then activated to a heterodimeric form. Ubiquitously expressed. Proteolytic cleavage at Gly-23 or Met-27 can give rise to the 50 kDa heavy chain and cleavage at Arg-313 or Lys-319 can give rise to the 27 kDa light chain. The heavy chain can undergo further proteolytic cleavage at Lys-169 or Arg-170 to give rise to 2 inactive 26 kDa fragments and the light chain can undergo further proteolytic cleavage at Arg-480 to give rise to inactive 17 kDa and 8 kDa fragments (By similarity). Disease susceptibility is associated with variants affecting the gene represented in this entry. Belongs to the peptidase S1 family.