Human prostate specific antigen (PSA) gene: structure and linkage to the kallikrein-like gene, hGK-1

Prostate Specific Antigen (PSA) is a member of the glandular kallikrein subfamily of serine proteases (1). Its expression is apparently confined to the duct cells of the prostate and as such is potentially useful as a serum marker for the treatment of prostate derived tumours (2). Using a PSA cDNA clone (3) as a probe, we have isolated a series of overlapping cosmid clones containing kallikrein-like sequences. By restriction mapping of these clones we have found that the PSA gene is located 12kb upstream from the hGK-1 gene (4), which is also expressed in the prostate (5). The human cosmid library was constructed by and an aliquot obtained from Dr. K. Choo, Murdoch Institute. No overlap was obtained with the renal kallikrein (KLK) gene which also maps to chromosome 19ql3 (3,6). The PSA gene sequence depicted (determined by the enzymatic method (7)) shows all exon and 5 ' and 31 flanking sequences. Variant TATA and polyadenylation sequences are underlined, splice donor and acceptor sequences are boxed. Numbers refer to distance from initiation of transcription, by analogy with the KLK gene (6). Coding regions are translated. OCCOQCTCICUOmWOCrTCTTTTT 1 Cto-CCCCCCTOTCTTTTCAAAeCOKflOTWUrrCC*TnOTOT rucusccmTCSTm: roiancTOTanui^iriMwift UKCUM U WULAIJ BLI mcixm IOJUCC w lllirrcCiiTrpftlLaTbTUajdiiCrtllMUi^i uUfcQ>Xj^l^j ^ 1 5kb TCCCTTCTCTCmCCTT MB lrf«l1«nrfl*roClrt«pm«jffliTlirfcrtlT»]torili^ us ffiniwccraria«uro*nOTCMJCOTWT its rfyijTN'Bii. iimf w f\^i|rorrTriTiTicii''i i n jinr S+B ciacTgcwawToaaCTaaiCTO IMS