CELL FREE SYNTHESIS OF HUMAN-PROTHROMBIN - IMMUNOLOGICAL CHARACTERIZATION OF THE TRANSLATION PRODUCT

mRNA prepared from adult and fetal human liver were translated in a cell free reticulocyte lysate system. The early precursor of human prothrombin, so called preprothrombin, was purified by immunoaffinity microchromatography. The precursor was identified by immunological competition as a single band displaying in sodium dodecyl sulfate-gel electrophoresis is Mr [relative MW] slightly lower than the Mr of human prothrombin (72,000 instead of 76,000). Immunological studies showed that human preprothrombin reacted more efficiently with antibodies raised against denatured prothrombin than with antiplasmatic prothrombin antibodies. The rate of synthesis of the precursor obtained under the direction of adult liver RNA was 10-fold higher than that obtained under the direction of fetal liver RNA.