PSA (prostate-specific antigen), the most useful serum marker for prostate cancer, is encoded by thehKLK3gene and is present in the serumas amixture of several molecular species. This work was performed to identify the hKLK3 transcripts in order to determine how many proteins resembling PSA are synthesized from thehKLK3gene and secreted in blood. Combined Northern blotting, molecular cloninganddatabase searching showed that thehKLK3gene produces at least 15 transcripts ranging in size from to kb. Polysomal distribution analysis revealed that the transcripts shorter than kb are efficiently translated in prostate cell line
