Human liver RNA-programmed in vitro synthesis of a polypeptide related to human apolipoprotein B

AbstractIn an in vitro synthesizing system programmed with RNA from human liver a polypeptide with an estimated Mr of 80000 (80 kDa)±1400 (mean±SD, n=5) was synthesized. This polypeptide could be precipitated with antiserum to a narrow density cut of LDL (d=1.030-1.055) or antiserum against the high-Mr form of apoB (apoB 100 [4]). The synthesized protein is immunologically related to a 75 kDa protein isolated from LDL. We suggest that the 80 kDa protein represents a primary translation product of apoB synthesized in human liver