Recombinant Human Cathepsin Z Protein (His Tag)

Cathepsin Z (CTSZ); also known as Cathepsin X or CATX; belongs to the C1 family of lysosomal cysteine proteases. Its gene structure and activity properties show several unique features that distinguish it clearly from other human cysteine proteases. It has a very short pro-region that shows no similarity to those of other cathepsins and a three-residue insertion motif that forms a characteristic ‘mini loop’. Cathepsin Z exhibits mono- and di-peptidase activity at its C-terminus; and in contrast to cathepsin B; it does not act as an endopeptidase. It is restricted to the cells of theimmune system; predominantly monocytes; macrophages and dendritic cells. Cathepsin Z is widely expressed in human tissues; suggesting that this enzyme could be involved in the normal intracellular protein degradation taking place in all cell types. It is capable to cleave regulatory motifs at C-terminus affecting the function of targeted molecules. Cathepsin X may regulate also the maturation of dendritic cells; a process; which is crucial in the initiation of adaptive immunity. Furthermore; higher levels of Cathepsin Z are also found in tumour and immune cells of prostate and gastric carcinomas and inmacrophages of gastric mucosa; especially after infection by Helicobacter pylori. Cathepsin Z is also ubiquitously distributed in cancer cell lines and in primary tumors from different sources; suggesting that this enzyme may participate in tumor progression.