passages.id: split_4_test_628_passage
passages.type: progene_text
passages.text: The human tissue kallikrein ( KLK ) family of serine proteases , which is important in post - translational processing events , currently consists of just three genes - tissue kallikrein ( KLK1 ) , KLK2 , and prostate - specific antigen ( PSA ) ( KLK3 ) - clustered at chromosome 19q13. 3 - 13.4 .