Biochem/physiol Actions

KNG1 (kininogen 1) exists in low and high molecular weight forms which are precursors for bradykinin and kallidin (Lys-Bradykinin), respectively. The high molecular weight kininogen (HK) functions as a cofactor for the stimulation of surface-bound Hageman factor (Factor XII) by kallikrein. HK is subsequently required for the activation of prekallikrein and Factor XI by the activated Hageman factor. These steps are essential for the initiation of coagulation, fibrinolysis, and the production of vasoactive peptides. Ile581Thr polymorphism in KNG1 gene is linked with increased susceptibility to venous thrombosis.

General description

LMW Kininogen is involved in blood pressure regulation since it is an endogenous protein substrate for tissue kallikrein. Proteolytic cleavage by kallikrein releases vasoactive bradykinin from LMW kininogen. In addition, LMW kininogen, like HMW kininogen, is a major extracellular cysteine protease inhibitor.

KNG1 (kininogen 1) gene is localized to human chromosome 3, and codes for both high and low molecular weight kininogen. The high molecular weight kininogen (HK) is a 120kDa single chain glycoprotein.

Physical form

Lyophilized from 10 mM Na acetate, pH 5.5 with 200 mM NaCI .

Reconstitution

In water or aqueous buffer