Biosynthesis of prostatic acid phosphatase in a normal human cell-line.
The biosynthesis of the prostatic form of human acid phosphatase was studied in normal embryonic lung cells, WI-38, by metabolic labeling with tritiated leucine and [32P]phosphate, followed by specific immunoprecipitation, gel electrophoresis, and fluorography. Of the total tartrate-inhibitable acid phosphatase activity in WI-38 cells, 30% is due to the prostatic form. The primary translation product that leads eventually to the mature prostatic enzyme is a precursor polypeptide of 112 kDa. The precursor polypeptide is processed to mature polypeptides of 59, 55, and 49 kDa via an intermediate 91-kDa precursor. WI-38 cells also secrete a 113-kDa peptide into the medium. The precursor and mature polypeptides are glycosylated and phosphorylated. Upon treatment with endo-beta-hexosaminidase H, the apparent molecular weighs of the polypeptides are reduced by approximately 4 kDa and phosphate is lost.
D000135:Acid Phosphatase / Q000096:biosynthesis*; D002460:Cell Line; D004591:Electrophoresis, Polyacrylamide Gel; D010450:Endopeptidases / Q000378:metabolism; D005470:Fluorometry; D006801:Humans; D007930:Leucine / Q000378:metabolism; D008168:Lung / Q000196:embryology / Q000201:enzymology; D008297:Male; D008970:Molecular Weight; D010446:Peptide Fragments / Q000032:analysis; D010710:Phosphates / Q000378:metabolism; D011467:Prostate / Q000201:enzymology*; D012661:Semen / Q000201:enzymology; D012697:Serine Endopeptidases
D010446:Peptide Fragments; D010710:Phosphates; D000135:Acid Phosphatase; D010450:Endopeptidases; D012697:Serine Endopeptidases; C028344:glutamyl endopeptidase; D007930:Leucine