Degradation of epidermal growth factor receptors by cathepsin L-like protease: inhibition of the degradation by c-Ha-ras gene products.

Extract of NIH3T3 mouse fibroblasts contains a protease which can cleave epidermal growth factor receptor (EGF receptor). This protease was tentatively named cathepsin X and purified to near homogeneity. The characteristics of cathepsin X were similar to those of cathepsin L and the proteolytic activity of cathepsin X was inhibited by c-Ha-ras gene products.