HTG-VLDL1, like LDL, bind with high affinity to electrophoretically transferred, isolated LDL receptors partially purified from bovine adrenal glands. Ligand blotting techniques show that binding is calcium dependent; little or no binding of LDL or HTG-VLDL1 is observed in the presence of 10 mM EDTA. HTG-VLDL1 does not bind in the presence of 7 mM suramin, an inhibitor of LDL binding to the LDL receptor. Pretreatment of LDL with either thrombin or trypsin does not affect apoB-mediated LDL binding to the LDL receptor. ApoE-mediated binding of HTG-VLDL1 to the blotted LDL receptor is abolished or greatly decreased by thrombin treatment of HTG-VLDL1 trypsin treatment of HTG-VLDL1 abolishes binding. Reincorporation of apoE into trypsinized HTG-VLDL1 restores binding. These studies demonstrate unequivocally that HTG-VLDL1 bind to the LDL receptor, that the binding of HTG-VLDL1 to the isolated LDL receptor is mediated through the thrombin-accessible apoE, and that HTG-VLDL1 which bind via potentially dissociable apoE rather than non-tranferable apoB can be used for ligand blotting.
|Original language||English (US)|
|Number of pages||8|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - Aug 29 1986|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology