Activation by cathepsin G of latent gelatinase secreted from rat polymorphonuclear leukocytes.

Rat polymorphonuclear leukocytes secrete a latent gelatinase with a molecular weight of about 96 kilodaltons (kDa). Activation of the latent 96-kDa gelatinase by cathepsin G was studied by using sodium dodecyl sulfate-substrate polyacrylamide gel electrophoresis. Cathepsin G activated the 96-kDa gelatinase by converting it to two lower molecular-weight species of 76 and 61 kDa, which were slightly different from the gelatinase species generated by treatment with 4-aminophenylmercuric acetate, an activator of latent gelatinase.