Function
Urokinase (UK) is a serine protease whose principal substrate is plasminogen – the inactive zymogen of plasmin[1]. UK consists of 3 domains: ligand-binding domain and kringle and growth factor domains. Prourokinase (PUK) is the inactive zymogen of UK which becomes active by proteolytic cleavage into catalytic domain (residues 179-431) and short chain (residues 156-178).
Relevance
Increased levels of UK are associated with poor prognosis in patients with breast cancer and thus is used as prognostic markers for the disease[2].
