BIOC 406 Lecture Notes - Lecture 5: Cholesteryl Ester, Ester, Clathrin
Document Summary
Cholesterol transport: chylomicrons get synthesized in the intestine and vldl in the liver. Some of the chylomicron and vldl remnants go back into the liver, but some vldls form into idls and turn into ldls in circulation. Low-densit lipoproteins (ldl: a single apob-100 on the surface, chylomicrons are huge. Ldls are a bit more regular: ldls have about 1500 molecules of cholesterol esters, shell: 500 molecules of cholesterol; 800 phospholipids. Cells take up ldls by receptor-mediated endocytosis (how really big. Things cross the membrane: there are specific receptors on the surface of the cell that can bind vldl particles. This gets internalized by clathrin-mediated endocytosis: the clathrin-coated pit (invagination) continues to grow, surrounded by a clathrin cage that gets internalized, the clathrin surrounding the vesicle gets released and recycled. It will hydrolyze all the fats, (lysosome) and degrade the entire vldl particle.
