Molecular cloning of a human cDNA encoding putative cysteine protease (PRSC1) and its chromosome assignment to 14q32.1.

We have isolated a novel human cDNA encoding a protein of 433 amino acids which shows 40% sequence identity to a hemoglobinase of Schistosoma japonicum, one of the cysteine proteases in the pathway by which trematodes degrade host-cell globin. It also has 36% identity to a cysteine protease of the soybean Glycine max that processes proproteins of various vacuolar proteins into mature form after translation. Considering the sequence similarities among these proteins in such widely divergent species, the human cDNA reported here appears to represent one of a group of genes that have been well conserved during evolution. Northern-blot analysis revealed the strongest expression of this gene in kidney, among the human tissues examined. By fluorescence in situ hybridization, we determined its chromosome location at 14q32.1.