Recombinant humman Receptor-associated Protein (RAP) fused to GST, expressed in E. coli and subsequently cleaved with thrombin to remove GST. Antagonizes the ligand binding of certain members of the low-density lipoprotein receptor family such as low density lipoprotein receptor-related protein (LRP) and very low-density lipoprotein (VLDL) receptor. Promotes the proper folding and subsequent exocytic trafficking of the wild-type low density lipoprotein receptor (LDLR) and several of its class 2 mutants. Expressed as a GST-fusion protein that is subsequently cleaved with thrombin. Typical concentrations to block LRP or VLDL receptor are 200-300 nM. For antagonism of LDLR, 1 µM is recommended.