MCB 2210 Lecture Notes - Lecture 18: Golgi Apparatus, Cisterna, Isomerase
Document Summary
Proteins on the cytoplasmic face of vesicles regulate budding and fusion; 1- budding: the mechanical process of membrane budding is driven by a complex of cytoplasmic proteins that assembles on the outside (cytoplasmic face) of budding vesicles. They coat the vesicle surface so are called coat proteins: different vesicle types have different coat proteins. Copii coats vesicles moving er to golgi (retrograde transport backwards) Copi coats vesicles moving golgi to er and from more trans golgi to more cis golgi (anterograde direction) Clathrin coats vesicles moving from tgn to surface, and from surface to endosomes, lysosomes. Endocytosis: the contents of the vesicle apparently play no direct role in triggering budding. Different coated vesicles can be distinguished morphologically. A class of small g proteins regulates budding: these cytoplasmic g proteins associate with membranes. Budding: sar1 membrane binding gtp exchange, copii coat assembly, gtp hydrolysis, coat disassembly. Non-hydrolyzable analogs of gtp such as gtp-gamma-s trap vesicles in the coated form.