Most proteins in the ER are glycosylated Proteins in cytosol are rarely glycosylated original precursor oligosaccharide added to most proteins in the ER
Protein glycosylation in the rough ER
Oligosaccharides are used as tags to mark the state of protein folding
Misfolded proteins are exported from ER and destroyed
Chapter 13 Intracellular Vesicular Traffic
Roadmap of protein traffic inside cell
Endocytic and secretory pathways red = secretory green = endocytic blue = recycling
5.14 Figure 5.14 figure jpg
Vesicular transport
There are various types of coated vesicles
Different coats are used for different transport steps in the cell
Coated Pits are the sites of receptor mediated endocytosis Clathrin protein cytosol Material to be taken up by cell
Clathrin-coated pits and vesicles
Structure clathrin triskelion
Arrangement of triskelion on surface of clathrin coated vesicle
DVD Clip 57
Assembly and disassembly of clathrin coat
Dynamin pinches clathrin coated vesicles from the membrane
Electron micrograph from Drosophila mutant
Resting Chemical Synapse
Drosophila mutant can not recycle synaptic vesicles
SNARE proteins guide vesicular transport
Active Chemical Synapse
Interaction of SNARE proteins while docking synaptic vesicle at nerve terminal
Model for membrane fusion. Tight SNARE pairing forces water molecules from area between lipid bilayers
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