CLONING OF CDNA FOR HUMAN GRANZYME-3

A serine protease gene was cloned from cDNA prepared from tissue isola ted from human ascites, The gene codes for a protein of 264 amino acid s, identified as human granzyme 3 by the N-terminal amino acid sequenc e, Granzyme 3 has the expected features of the chymotrypsin family of serine proteases, and is closely related to other human granzymes (40- 45% identity). However, the closest granzyme 3 homologue is the recent ly characterized rat tryptase, RNK-Tryp-2 (75% identity), From Norther n blots, granzyme 3 appears to be highly expressed in peripheral blood leukocytes, spleen, thymus, and lung tissues.