Molecular cloning and characterization of novel prostate antigen cDNA's

Three different prostate antigen cDNA's were isolated from a PC 82 prostate tumor cDNA library. PA 75 has a size of 1.4 kb and contains the almost complete information for the 35 kD prostate antigen preproprotein. The 1.6 kb PA 525 cDNA lacks about 0.2 kb of the 3'-non coding region and contains an additional internal 0.4 kb fragment as a result of alternative splicing. PA 424 represents a 0.6 kb variant of PA 75. It contains a 0.15 kb internal fragment and a poly(A) tail preceded by an AAGAAA motive at the 3'-end. The predicted protein products of PA 525 and PA 424 will be different from PA 75 at the C-terminal end. In RNA preparations of two human prostate tumors (PC 82 and PC EW) seven different prostate antigen transcripts can be detected ranging in size from 0.5 kb to 5.6 kb. PA 75 cDNA represents the major 1.5 kb mRNA. PA 424 correlates with a 0.9 kb transcript and PA 525 with a 1.9 kb mRNA species.