BIOL 201 Lecture Notes - Lecture 19: Cytosol, Hydrolysis, Secretion
Document Summary
Membranes: membrane bounded organelles are everywhere, continuous membrane flow and exchange between compartments (e. g. er and golgi, cell use markers to identify organelles, and determine where they should go, fluid mosaic model. Pe (phosphatidylethanolamine) molecules have tails extended at an angle placing these lipids molecules at desired locations creates curvature. Head group side also contributed to curvature: protein scaffold. Ldl particles: low density lipoprotein particle bad cholesterol, mixture of fat & protein particle from digested food, metabolized by cells and reused. Ldl are ferritin labeled, allows cell to bind. Cell build internal structure under membrane helps membrane to fold inwards. Ap2 complex makes actin polymerization near endocytosis assembly point. Clathrin: trimer that aggregate to form a cage structure surrounding the vesicle the curvature of the membrane itself also favors clathrin polymerization. Stacking on top of each other, forms a collar structure at the pinching point and cleaves vesicle from plasma membrane.
