protein_function: Inhibits factor X (X(a)) directly and, in a Xa-dependentway, inhibits VIIa,tissue factor activity, presumably by forming aquaternary Xa,LACI,VIIa,TF complex. It possesses an antithromboticaction and also the ability to associate with lipoproteins inplasma (By similarity)..
TFPI(Tissue factor pathway inhibitor),also known as EPI, LACI or TFPI1, is a single-chain polypeptide which can reversibly inhibit Factor Xa (Xa) and Thrombin (Factor IIa). The gene for TFPI is located on chromosome 2q31-q32.1, and has nine exons which span 70 kb. TFPI consists of a highly negatively-charged amino-terminus, three tandemly-linked Kunitz domains, and a highly positively-charged carboxy-terminus. TFPI contributes significantly to the inhibition of Xa in vivo, despite being present at concentrations of only 2.5 nM.