ApoB100 main distribution and function?

ApoB100 main distribution and function?

• A. Main distribution: VLDL, IDL, LDL; Function: Structural, LDL-Receptor Ligand
• B. Main distribution: HDL; Function: Structural
• C. Main distribution: CM; Function: Structural
• D. Main distribution: CM, VLDL; Function: Enzyme activator

Answer: (A)

ApoB-100 is the liver-derived apolipoprotein that appears on VLDL, IDL, and LDL particles, serving as the structural protein of the lipoprotein and as the ligand that binds the LDL receptor for uptake by liver cells. It is not present on HDL (which carries apoA proteins) and is not on chylomicrons (which carry apoB-48). The primary roles are to provide the structural integrity of these particles and to mediate receptor-mediated clearance via the LDL receptor. That’s why the distribution VLDL, IDL, LDL with a structural role and LDL receptor ligand function is the best description. Chylomicrons carry apoB-48, and HDL does not rely on apoB-100, so the other options don’t fit.

ApoB-100 is the liver-derived apolipoprotein that appears on VLDL, IDL, and LDL particles, serving as the structural protein of the lipoprotein and as the ligand that binds the LDL receptor for uptake by liver cells. It is not present on HDL (which carries apoA proteins) and is not on chylomicrons (which carry apoB-48). The primary roles are to provide the structural integrity of these particles and to mediate receptor-mediated clearance via the LDL receptor. That’s why the distribution VLDL, IDL, LDL with a structural role and LDL receptor ligand function is the best description. Chylomicrons carry apoB-48, and HDL does not rely on apoB-100, so the other options don’t fit.