Open AccessSynthesis and processing of human chorionic gonadotropin subunits in cultured choriocarcinoma cells.
Author(s) -
Raymond W. Ruddon,
Charlotte Hanson,
Nancy J. Addison
Publication year - 1979
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.76.10.5143
Subject(s) - human chorionic gonadotropin , protein subunit , choriocarcinoma , glycoprotein , g alpha subunit , gel electrophoresis , polyacrylamide gel electrophoresis , biology , sodium dodecyl sulfate , alpha (finance) , intracellular , biochemistry , gonadotropin , beta (programming language) , molecular mass , microbiology and biotechnology , chemistry , hormone , enzyme , gene , medicine , genetics , construct validity , nursing , computer science , programming language , patient satisfaction
Pulse and pulse-chase experiments have identified the presence of partially glycosylated precursors of the alpha and beta subunits of human chorionic gonadotropin (hCG) in cultured JAR choriocarcinoma cells. The alpha subunit precursor has an apparent molecular weight (by sodium dodecyl sulfate/polyacrylamide gel electrophoresis) of 18,000 (compared to 22,000 for fully processed alpha subunit); the beta subunit precursor has an apparent molecular weight of 24,000 (fully processed, 34,000). Both of these precursors appear to have an intracellular half-life of at least 1 hr and to contain the mannose core but not the terminal carbohydrate sequences. Fully processed alpha and beta subunits do not accumulate intracellularly, indicating that further processing of the precursors is followed by rapid secretion.