Figure 4.
Metabolic labeling studies for intracellular fXI. BHK cells were transfected with pZEM229R expression vector22 containing the following cDNAs: (1) none; (2) wild-type fXI; (3) fXI-Phe283Leu; (4) fXI-Gly350Glu; or (5) fXI-Gly400Val. Stable transfectants for each construct were grown in media containing [35S]-cysteine for 24 hours and then lysed by radioimmunoprecipitation assay (RIPA) buffer treatment. Immunoprecipitates were prepared from cell lysates and then size fractionated by SDS-PAGE, followed by autoradiography. The positions of disulfide bond–linked dimeric fXI (dimer) and nondisulfide bond–linked fXI (monomer) are shown on the right. Positions of molecular mass standards are shown on the left in kilodaltons.